MS20 Power Reduction Success!

[Jon5ja]

http://people.txucom.net/srbarclay/images/ba.jpg

Hi all.

This evening I received some parts I ordered for an attempt to reduce the idle power consumption of the MS20 PIR detectors. ###The picture above shows the current draw of the "stock" unit versus the modification I just finished. ###By changing three components, I was able reduce the idle power consumption to less than a fifteenth the original value.

*** EDIT ***
Here's a link to the modification procedure for anyone who doesn't want to read through this entire thread hunting for it:
Low Power Mods (http://people.txucom.net/srbarclay/LowPower.htm)

Components changed were:

1.) U1 changed from an HA17324 to a TLC27L4CN ### $0.93
2.) Zener diode D4 changed to an LM385Z-2.5NS ###### $0.72
3.) Resistor R8 changed from 4.7K to 100K ### ### ### ### ### ### $0.05 ?

I didn't buy the resistor :-)

Because the zener D4 needed some minimum current to behave, the original circuit used a 3.3-volt zener with a 4.7K pull-up resistor, providing 500 uA of bias through the zener. ###This was on the edge of the lower limit of working current, as indicated by the fact that the working voltage was 2.5 volts. ###I attempted to increase R8 with the existing zener, but the regulated voltage immediately fell off to nearly nothing.

Looking around in the catalogs, I found the LM385Z-2.5 micropower zener -- it only needed 20 uA of current to do its thing, so that meant I could reduce R8 to (2.5 V / 0.02 mA) = 125K. ###To be just a hair on the safe side, I used 100K for R8 to bias D4 at 25 uA.

According to the datasheets, typical current draw of the TLC27L4CN is 40 uA, so looking at the schematic, the currents added up like this:

40 uA - TLC27L4CN
25 uA - R6
25 uA - R8
10 uA - R9 (measured)
24 uA - R14
------------------------- 124 uA ###Expected total idle current

So, as you can see in the picture above, I'm quite pleased with the 110 uA actually measured after these three modifications were done.

You could lose another 20 uA or maybe 30 uA by increasing the values of R6 and R7, and maybe R4, but we're probably already to the point of diminishing returns.

Hope this is helpful. ###Now I'm thinking... maybe a 9-volt battery?

Cheers,

Jon

[davered1]

I give you another week and I will be able to run my sensors off of my good looks!!!

Good job!! that is LOW!!

[ArkansasElkHunter]

Thats incredable. ###You are THE MAN. ### Where did you order the components at. ###Is it as simple as it sounds.

[Jon5ja]

I ordered the parts from Digi-Key. ###Unfortunately, they have a $5.00 charge for orders under $25, although if you have a handful of cameras you can probably muster up a $25 order anyway. ###When I ordered this stuff, I ordered a bucket full of stuff including that mentioned above, plus various opto-couplers and solid state relays for experimentation. ###There's a price break at 25 ea. for lots of this stuff so I have ... lots of this stuff :-) ###Probably only GAntley is close enough to do the "Hey, neighbor, can you spare a TLC27L4CN?" thing.

The only un-simple thing is replacing the op amp. ###If you don't have a desoldering iron, it would behoove you to go get one. ###Even with Radio Shack's cheapie desoldering iron, it only took a minute or two to remove the factory chip and solder in the new one.

The LM385Z-2.5 zener looks different than the one it's replacing -- it's in a TO-92 package (looks like the transistors already on the board), but it behaves like a zener. ###If you're looking at the flat side of the LM385Z-2.5 with the leads down, the left-most lead is not used... I just cut it off. ###The middle lead is the cathode (the "pointy" end of the diode) and the remaining outside lead is the anode. ###Spread its remaining legs apart and slide them into the holes formerly occupied by D4.

The 100K - for - 4.7K resistor swap isn't too tricky...

Jon

[Jon5ja]

OK, I said in my first post above that we were "probably already to the point of diminishing returns" ... but I'll let you be the judge.

I (of course) went ahead and replaced R6 and R7 with 470K resistors, and I replaced R4 with a 150K resistor. ###Regulation seems perfect (5.002 volts!) and idle current is now 79 uA. ###So, 3 more resistors is worth another 31 uA, so maybe it is worth it...

That'd make the difference from the original a 21X improvement :smile-yellow:

Jon

[passgas55]

Can these mods be incorporated with the mods of the internal timer?Man that MS20 would be hard to beat. Thanks

[Jon5ja]

Yes, the the low-power mods should work with or without the other stuff.

One thing I did notice just before I went to bed this morning -- sometimes, if there's just barely enough movement to trigger the circuit, it seems the "shutter time" is sometimes reduced. ###Once I noticed that it was only about 4 seconds.

I don't know if this is due to the new op amp having less output current (it is basically charging C13 as hard as it can when first triggered, limited only by the output current capability of the op amp), or if maybe this was something that occurred when I dropped the supply voltage from 12V to 6V. ###It might even be a combination of the two. ###I'll investigate it tonight and see what I can find.

Jon

[Tinhorn]

Man that's good,

With the internal 2 stage timer and battery efficiency mods, the MS20 shines even more.

Now Jon, get to work on an Adjustable Sensitivity Feature ### he he

BTW ### ###.11 ma's with a 9v battery (590 ma battery ampacity) calc's to 7.5 months !

Can't beat that with a stick.......

Tinhorn

[jayber]

Excellent work Jon.....and thanks for sharing it with us! ###You deserve a :toast-yellow: ###Now I'm gonna have to get me some of those parts and try it out!

[Jon5ja]

Hi, Tinhorn.

The gain is determined primarily by the ratio of R13 to R12 -- currently set to a factor of about 300.

You could obviously adjust it either way, but do you think you typically need more gain or less than what's factory supplied?

[Tinhorn]

The MS20 sensitivity question boils down to 2 or 3 things I think, and reducing the senitivity will help prevent some problems:

1. ###Too many "false alarms", especially in the summer daylight hours
### ### ### ### ### ### which is why some are using furnace thermostats to turn
### ### ### ### ### ### off the camera when the temps are above ~80 degrees

2. ###It has a range of 60 or 70' - which is fine in the daytime I guess but most
### ### animal pix's occur at night and the flash range is 30' or so. ###
### ### ### ### ### ### ### (Little Eyeballs in the dark)

3. ###Tweetie birds and other small critters setting off the MS20 too much
### ### ### ### ### ###also, probably detecting animals behind the brush that the
### ### ### ### ### ###camera can't see thru

### ### ### ### ### ###These animals are probably not noticed in the pix's, making us
### ### ### ### ### ### think it's false alarms

Tinhorn

[gantley]

gee thanks jon.....sigh....

i just got the inhibit mod documented.... ###not this. ###and i cant just ignore this mod.

you see guys, this is why jon makes me sick some time.... ###he is just darn good at this stuff and i have trouble understanding how the transister works. ###the stories we could tell.

[Jon5ja]

Thanks Davered, AEH, pg55, Tinhorn, hag, and jayber for the encouragement!

Re: Tinhorn's sensitivity issues...

1.) It should be relatively easy to add a thermistor to the "inhibit" circuit to disable operation above a particular temperature, although I couldn't use 80 degrees as the cutoff here or I'd never take a picture :-) ###I considered using a thermistor to reduce the gain of U1B, but I don't think the temperature coefficient of most thermistors is going to be "fast" enough (most change like 4% per degree C) to set the gain without using a bridge circuit, and that would likely require another op amp to implement.

2.) It appears feasible to use the supplied LDR (R22) to modify the gain of U1B for day versus night operation. ###Care to guess at objective gain numbers for day and night operation? (Factory gain is about 300)

3.) Yep, generally reducing the gain is probably the answer for this one.

In general, if you just want to experiment manually with the gain, stick a 50K 10-turn pot (so it won't be so touchy) in place of R12 and tweak away.

[Archilochus]

Great job Jon!!
Good to hear the 27L4 worked out - it's just the part I had my eye on (it's the part I use in most of my "home-brew" sensors). ###Replacing that power hogging Zener was pure genius! ###Have to check out those parts.

Thanks,
Archilochus

[coyotebandit]

Jon5ja,

Pretty amazing work, I'm very impressed. I don't suppose you would be interested in looking into the RS PIR to see if any "HomeBrew" improvements can be made? I think sensitivity would be the first thing needed to reduce the number of false pics. I know some commercial units have a switch for animal body size, that might be a nice option. Otherwise a thermostat and day/night operation would be second in my book. Anyway, we all appreciate your hard work and knowledge of electronics. Great job with the MS20 enhancements!

:smiley-thumbs-up:

Thanks

CB

[gantley]

jon,

with changes in the power input, we will need to make value changes in the inhibit circuit want we?

[Jon5ja]

Gary:

If you change from 6 volts back to 9 volts, everything should work fine except the shutter time and the inhibit time will be increased somewhat. ###That shouldn't be a problem since the shutter time is still much less than the problematic 3-minute zone.

In my case, since I'm using a 5-volt, 30 mA relay, I'd have to add a resistor in series with the coil to get rid of the other 4 volts (4 / 0.030) = 133 ohms, so I'd probably use a 120-ohm resistor in series. ###Actually, I just received an assortment of optocouplers (optoisolators?) last night, so I may not end up with a relay in the circuit at all.

CoyoteBandit:

Thanks for the compliment; ###if I can come up with one of the RS PIRs I'll take a look at it and see. ###I'm about to get tied up at work and at play with other obligations for a few weeks, so I may not get to do much more immediately.

I've already done the calculations for the thermistor mod to shut off the MS20 when it gets hot (a resistor, a thermistor, and a diode), and I also did the calculations for what it'd take to do a daytime or night time only mod (a couple of resistors, the LDR, and a diode), but I haven't had time to decide on a good layout yet for either one, and I wouldn't want to "publish" something I hadn't tested.

Hey Arch:

I just found your old Web page -- I see that you are also using the 81250SGY regulators. ###I received some of those yesterday also, and I intended to use one of them instead of the LM385Z-2.5 regulator mod, but I decided it'd be easier to just tell people how to replace those three components than to explain how to get the pin to ground, modify the circuit to still provide the 2.5V reference etc. ###You and I have followed a lot of the same thought processes. ###Now I'll have to go examine your pages to be sure I'm not coming up with something you already came up with! :smile-yellow:

Cheers,
Jon

[gtk]

Jon5ja, Tinhorn, Archi ###and others who understand this jarble.... ###

Is there anyway to do a braindump so some of us "not so electronic-literate" people could upload it, and maybe have a clue as to what your talking about when you all are coming up with these "new ideas" ###?? ###

If it were not for people like ya'll (and jesse), this stuff would never be even remotely possible for me to complete. ### Just a quick "thanks" ###for making all this fun and understandable (the ###understandable part being step by step instructions with pictures) ....

I thinks i'll wait a couple of weeks before building my next cam, so i can incorporate all the latest greatest mods to the ms20....

:smiley-thumbs-up:

Thanks again.....

[Jon5ja]

Hi, gtk,

Sorry, it's easy for me to get caught up in the moment and start babbling my thoughts.

I've taken pictures of most of the mods I've done, and I'll try to get them posted before long. ###GAntley also has been taking pictures and putting them on his Web page, so before long you should have a couple of examples to look at.

I prefer pictures also... instructions are used only as a last resort!

Jon

[Pgumby68]

An MS20 that could run 7 1/2 months on a 9 volt, now that is what home brew dreams are made of!!! ###Like AEH said, You da man. I'm in the same boat as GTK, I need simple drawings and pictures to help me out. I need to know how to make it run on 9 volts first and then how to make it last that long. This is where Tinhorn's brilliance shine through before. The way he dissected the RS-425 made it easy for even the most simple minded of us (ME) to understand. You guys amaze me everytime I log on. Keep up the good work.

[gizz]

WOW! I've got some catchin up to do. This is great stuff and very good news as i have a bunch of cams with the ms20 in them and 12V gel batt's. Boy what a difference it would be to solder in a 9V batt plug and use standard 9V alk batt's!! Especially if they'll last 6 or more months. I've started switching to the Lamson PIR but I've always liked the results i got with the MS20 and it's cheap to buy. Good work to all of you that have worked on this mod to the MS20.

[jayber]

I think Jon's work/contributions on how to make the MS20 more efficient is pivotal and should be added to 'Random Thoughts' to be retained at the top of the forum for all to see. ###Moderator?

[Jon5ja]

Thanks jayber, but I humbly suggest we wait until a handful of people have tried and tested the modification to be sure it's repeatable, reliable, and doesn't cause any unforseen negative effects.

[Brian]

Jon5ja,

Nice work Jon. ###Where abouts are you in East Texas. ### I live in Texarkana.

[Jon5ja]

Thanks, Brian.

I'm out here in the Davy Crockett National Forest, 30-something miles west of Lufkin. ###I'm in a suburb of Possum Walk, GAntley's home community :-)

To any of you guys out there using optocouplers to trigger the Owl cameras:
1.) What optocoupler are you using?
2.) How much current are you supplying to the LED side?

I guess this is still in the Power Reduction vein, since that's my motivation for getting rid of the relay.

Jon

(Edited by Jon5ja at 1:18 pm on June 12, 2002)

[gantley]

jon, i am going to note the power convertion on my procedure without any details at this point. ###

do you think we can get by with the 9vdc relay in the circuit and still have a good power to battery ration? ###this could give us two options for switching control...relay that just slobers in place or the optoisolator......

gda

[Brian]

Jon5ja,

I use the PS2501-2 from Mouser.(Thanks Arch) ###It is a dual opto. ###If you only want one then the PS2501-1 is the part number. ###Also, I use the surface mount version and not the DIP. ###They have both styles.

I power mine from the output pin of my PIC microcontroller. ###This is a 5 volt output. ###I use a 10K resistor which reduces the current to the microamps. ###If you try to put two pins together from the camera you will ###have to decrease the 10K to 1K. ###The current draw for the opto was approximately 300uA with the 10K resistor.

They are very simple to use but they are directional. ###The collector of the opto will have to go to the shutter or focus and the emitter of the opto will have to go to the common of the camera.

I have some schematics at the end of my PIC document if you would like to see the document I can email it to you.

[Jon5ja]

OK, thanks, Brian... you answered my unasked question about how the camera was configured (I don't have one yet).

I ordered some PS2501-2's the other day, along with some of the PS7111-2A MOSFET output "solid state relays". ###That was a week ago, I don't remember now why I picked that one :-) ###Hopefully, I'll get a camera before long and see how that goes.

Yes, if you have a link to the PIC document on a web page I'd like to see it or else I'd appreciate it if you'd e-mail it to me at Jon5ja@yahoo.com

I don't have any SMT equipment, and I think my eyes may be getting too bad to see that small anyway! ###Maybe I'll try it one day.

Thanks,
Jon

[kmitch]

I'd be thrilled to get rid of the electromechanical relays. I recently got an introduction to something new to me in relays. I found some 5v spdt relays at a local electronics surplus outlet. They were $1.95 each. Just the right size to go on the MS20 board but not a direct replacement. They were really small so I never questioned the coil resistance. When I tried on in a MS20 they would not operate. The coil resistance was 62 ohms. It was pulling about 100 ma at 6v. The MS20 could not produce enough current to drive the coil. In addition, they already had a supression diode inside the case which I didn't find until it was already in the circuit.

Lesson is everything which is small is not low current. At present I'm using the RS reed relays.

Keith

[Jon5ja]

Gary,

Re: using the relay with a 9V battery

It really shouldn't be a problem since you're only going to pulling that 10 or 20 or 30 mA for 10 seconds or so each time you take a picture, and with a normal roll of film, that isn't all that many times. ###My biggest concern, though, is after the battery gets kinda weak, I fear the load from the relay might yank the supply voltage around enough to cause the MS20 to misbehave. ###So... if we could run an opto off 0.5 mA or so, it's just one more thing to help ease your (and my) mind.

I don't yet have a camera with which to experiment, but I'm not entirely sure we need a relay OR an opto ... since the MS-20 is insulated and there's no other connections to the camera other than the two trigger wires, you might be able to get away with a transistor or even a little MOSFET pulling virtually ZERO power... ###the requisite negative being that you can probably zap the MOSFET with static electricity. ###Anyway, I'll try it once I get a camera.

Gotta go do something different... wife is tired of electronic tinkering every night for the last week.

[Jon5ja]

Hi, Keith.

Ha, you just learned some of the same lessons I learned two nights ago! ###I was looking around for something within reach with a 5V relay on it, and picked up an old Aztech-Packard Bell modem/soundcard/nightmare-generator. ###After looking at it, I discovered it had some pretty interesting parts on it! ###3 little DPDT relays, 4N35 and IL250 optoisolators, some .001/3KV caps, 3 different 5-volt regulators... I almost felt ashamed about how many times I'd cussed those things trying to work on a neighbor's computer (only almost ashamed).

Anyway, I took out one of the relays, tested it and it clicked, wired it into the circuit and it wouldn't work. ###I took out another one, tested it out of circuit, put it in, and it wouldn't work either. ###I had already decreased the resistor to get more drive to the relay driver transistor; I had the meter in line and it read 60 mA when it kicked on... but no relay action. ###I though "Surely, they didn't put a diode inside the relay..." but they did. ###Fortunately, my little relays were 177 ohms, and worked once I quit fighting the internal diode.

Cheers,
Jon

[Tinhorn]

I agree with Jayber and Jon both,

The MS20 Mods belongs on the Random Thoughts post but we need it to be a little more finalized with some further tests, "As Built" pix's, etc. ### Just want the mods to be as finalized as possible so it will be a complete report and there won't be too many revisions.....

Am wondering who all made the mods so far and their results? ###I can't believe I've not had the time to tinker with an MS20 yet

Tinhorn

[gizz]

Tinhorn, I have one of my cams that needs rebuilt to a bad bear attack and the parts are ordered. As soon as i get them i will be trying out the mods. I will be attempting this without the use of the opto since i've already got the 9V relay soldered in.
These mods should be a huge improvement for the MS20 and would definately be a great addition to the Random Thoughts thread.

[jayber]

Well, I finally found 'U1' printed on the board. ###The bugger was hiding. ###But what is it associated with, the LM324N? ###(see link) ###Jon5ja mentioned a HA17324 (?). ###Where and what the heck is that? ###LOL

MS20 U1? (http://groups.msn.com/JessesTrailCamPics/jaybershomebrewpics1.msnw?action=ShowPhoto&PhotoID=926)

[Jon5ja]

Hi, jayber.

Yes, U1 is associated with the quad op amp chip, which is a type 324 originally. ###National Semiconductor's part number is LM324N, Hitachi's (I think) part number is HA17324 for the same chip.

Here's a link to a page I stuck together in Microsoft Word, so if it doesn't work right, please let me know:

MS20/WM2 Low Power Mod (http://people.txucom.net/srbarclay/LowPower.htm)

Regards,
Jon

[coyotebandit]

Jon,

Great job on the instructions, they look really good. That's a must add-on to the MS-20 mods on JHP. Thanks for all your hard work, I'm off to Wal-Mart to get an MS20!

CB

[Handcannon]

Jon, ### ### ### ### ### ### ### ### ### ### ### ### ### ### ### ### ### ### ### ### ### ### ### ### ### ### ### ### ### ### ### ### ### ### ### ### ### ### ### ### ### ### ### ### ### ### ### ### ### ### ### ### ### ### ### ### ### ### ### ###Great work, sure glad you got hooked up to this forum,these two innovations to the ms20 will undoubtedly make alot more people interested in using it rather than RS or Lamson,the power consumption had to be it's greatest drawback.I will be building one for a guy at work in the next couple of weeks and I am sure going to be trying both your mods on this cam. ### ###Thanks again everybody for your electronics expertise.

[Cabin Fever Bob]

Great Work Jon! I think everyone will agree that, YOU DA MAN!! :toast-yellow: ###:sunglasses-yellow:

[jayber]

Thanks for the clarification Jon. ###I removed a MS20 from a unit this morning that I have to repair and noticed that it had the HA chip. ###Plan on making the power reduction changes to it as well. ###Great work once again.......and excellent instructions!

[MCinIL]

Jon,thanks so much for all the work. I will now try the ms-20. The power savings will be great. I think everyone here will be able to modify theirs with your link. It looks easier with pics. Nice job on the directions. MC.

[Tinhorn]

I can see that was no 5 minute Job on that report Jon ! ! !

Real nice and Professional and along with the Opto-Coupler the batt's will last even longer......

Well Done!

Tinhorn

[gtk]

These are instructions "even I can follow"... ! ### ###Thanks all. ### ###

One question... ###Do I not need a relay now, if I make these modifications ?

Thanks.




(Edited by gtk at 9:50 am on June 19, 2002)

[Jon5ja]

Thanks, guys.

gtk, I just received a couple of Owl PF cameras yesterday (thanks, ******!), so I should know whether or not it'll work as shown on the web page by maybe Thursday night.

Regardless, according to those here with experience, this is the "standard" modification to eliminate the relay, although Brian pointed out that, depending on how you wire your camera, the resistor shown as 4.7K (limiting drive current to the optocoupler) might have to be as low as 1K. ###I noted on the page that its value might have to be decreased; I'll update the page when I have experimental data.

Jon

[ArkansasElkHunter]

Great job on the report Jon. ### I do like a picture

[JoelM]

Hi guys,

Ok for the really electronically impaired (me). If I read this right. These modifications will reduce power consumption and eliminate the use of the relay????

I was looking at the mod instructions. is tlc27l4cn also the part number??

I guess the real question is what are the part numbers and where did you get them?

I want to give this a shot. Thanks for any input.

Joel

[jayber]

Can somebody pass along the value for D1? ###I have a board with it already removed and I don't have a good one here to reference. ###It appears to be N4007, correct? ###Thanks in advance!

(Edited by jayber at 10:52 am on June 19, 2002)

[Jon5ja]

jayber,

D1 is a 1N4001 in mine. ###It's not really needed if you use the optocoupler instead of the relay; it's there to block the "kickback" from the inductance of the relay when you turn it off.

[JoelM]

Why can't I see all these posts from the forum. I can only see them when I click on post a reply????

Never mind.....didn't notice the second page!!!!! Ooooppppss.

(Edited by JoelM at 12:21 pm on June 19, 2002)

[Jon5ja]

JoelM,

Are you clicking on the "2" at the bottom to go to the second page of this topic?

Not to advocate any particular vendor (though Mouser and DigiKey are among my most frequent suppliers), go to http://www.digikey.com and type one of the part numbers into the Search blank and it'll pull up the price and availability. ###Be warned that DigiKey has a $5 charge for orders under $25, I think. ###Mouser doesn't have the LM385Z-2.5 listed that I can find. ###Here are the part numbers you're looking for:

###TLC27L4CN
###LM385Z-2.5NS
###PS2501-2

Those should all turn up a single entry in DigiKey's search.

[jayber]

Jon,

I've got D2 as a 1N4007 on my board as well and your mods list it as a 1N4001. ###None-the-less, I took the diode out of D2 and put it into D1. ###I didn't obtain any optocouplers on my last order so I'll be sticking with a relay for now. ###Thanks!

[JoelM]

Jon,

Thanks...

Does this eliminate the relay?

[Hill Hopper]

Jon, I haven't reviewed this real close yet, but was wondering if it would make it any easier if you could just wire on a small PCB (REAL SMALL) with the opto and maybe any other small components like the resistor. Like I said, I haven't had time to review it much yet, but a small add on board would be a piece of cake to etch.

[wfontjr]

the transistor for the inhibit circuit, digkey shows 2n2907pnp as being discontinued, what is a good replacement,

[Jon5ja]

jayber: ###The 1N4001 is a 1-amp, 50-volt (reverse) diode, where the 1N4007 is 1-amp, 1000-volt. ###Since they act as one-way valves, both can flow the same amount forward, but the 1N4007 can stand a lot more "backpressure". ###In this case, both D1 and D2 see a maximum of 25 volts or so "backpressure", so even a 1N4001 should work in either place (unless the design changed, and the one you're looking at is different from mine).

JoelM: ###The PS2501-2 is intended to replace the relay, but I haven't witnessed it firing an actual camera yet. ###I have it blinking an LED each time my 3-year-old wanders in. ###On the bench at this moment, though, is an Owl PF, so maybe I'll have a verdict before I have to go to bed.

******: ###A PC board would probably make it easier if you already had them and if you contrived the holes so you could stick wire stubs through the board and into place of the relay. ###For me, though, the trouble of etching and drilling a board would be more than the bother of getting the little wires on the PS2501-2 "dead bug" style. ###Plus, my wife doesn't like what the etchant does to her sink :mad-fumin-red:

wfontjr: ###Pretty much any general-purpose PNP transistor should work -- I picked a 2N2907 because there was one laying on the bench. ###You should be able to use a PN2907 (plastic version), 2N3906, ECG159, or even some of the Japanese transistors that start with 2SA or 2SB, like the 2SA733 that is used for Q1. ###Be aware that the lead order may be different: ###on most of the 2N or PN numbers aforementioned, the pin order will be EBC, whereas most of the Japanese transistors will be ECB. ###This is assuming that the transistors you're using are TO-92 cased (the little plastic case with a flat side and 3 leads sticking out the bottom). ###I'll try to get something up on the web page in the next few days, probably using a PN2907, to demonstrate.

[BOHUNTER]

OH NO, I CANT SEE THE PICS FOR SOME REASON!!!! NITEMARE ON THE HOMEPAGE....WAAAAA....ANY SUGGESTIONS. COMES UP AS AN EXPLORER PAGE FOR ME??? WHAT DO I DO WITHOUT PICTURES........I GET A BOX IN TOP LEFT CORNER WITH A TRIANGLE CIRCLE AND A SQUARE......????? OF EACH PIC AREA

THANKS ILL JUST SIT AND WAIT......DISTRESSED FROM STRESSING OVER THE STRESS OF NOT BEING ABLE TO SEE WHAT THE HECK IM LOOKING AT....LOL

WELL IVE WAITED TILL THE COMPUTER SHUT DOWN AND I CANT SEE THE PICS..GRRRRRRRRRR IF ANYONE KNOWS WHY I CANT OR CAN E MAIL IN SOME PICTURE FORMAT I WOULD DO BACK FLIPS!!! ### ### ### ### ### SANDT4450@AOL.COM

### ### ### ### ### ### ### SIGNED.....DISTRESSED

(Edited by BOHUNTER at 1:28 am on June 20, 2002)


(Edited by BOHUNTER at 1:32 am on June 20, 2002)


(Edited by BOHUNTER at 11:32 am on June 20, 2002)

[Jon5ja]

BOHUNTER (aka DISTRESSED),

I built the page quickly in Microsoft Word, and I'm quite unhappy with the default behavior, but I haven't had time to fix it yet. ###Two things I don't like that it's doing:
###1.) When you put the cursor over a picture that has a hyperlink to make it bigger, the cursor doesn't change to the "hand" or whatever. ###At least it pops up the "tip".
###2.) When you go to a page, even when it's still loading pictures, the browser give you no indication that you aren't just dead in the water -- the "world" doesn't spin in the upper-right corner of IE, and there's no status information at the bottom of the page. ###Chances are, if you'll go to the page and let it set for a few minutes the pictures will likely pop up (they did that to me today).

I'll try to fix that eventually. ###If anyone reading this knows how to do so, please volunteer the information!

If none of this works, try clearing your IE cache and try again.

[JoelM]

Jon,

After reading this post and your instructions several times. I am starting to get an idea of what to do.

I have one more question for you though.

The three resitors you list in your instructions. Did you get them from digikey also?
and are those the part numbers to look for??

Ok 3 questions :)

The 100k resistor that you show soldered to the optocoupler is that one removed from R24?

I think that will do me for now.

Thanks

Joel

[gizz]

Excellent and well done instructions.
I have some cams to retrofit.
I'll probably stick to the 9V relay for now since they are in place and working but the opto is a definate on any new ones.
Good Job!

[Hill Hopper]

I'M GOING TO TRY A LITTLE BOARD ABOUT 1/2 THE FOOTPRINT OF A RELAY THIS WEEKEND THAT WILL HAVE A PS2501-1 OPTO AND A RESISTOR. WON'T REALLY BE ANY DIFFERENT THAN THE "DEAD BUG", BUT OUGHT TO BE A LITTLE EASIER SOLDER AND INSTALL.

[Jon5ja]

BOHUNTER: ###I cleared my cache just now, and went back to the link and it loads fine here. ###Have the pictures ever loaded for you? ###Are you using a Windows machine? ###Which web browser version are you using?

JoelM: ###The resistors actually came from 30 years of collecting junk. ###DigiKey (http://www.digikey.com), Mouser (http://www.mouser.com) and Jameco (http://www.jameco.com) (among others) have suitable resistors. Any ordinary non-surface-mount 1/8- or 1/4-watt carbon-film or metal-film resistors should work fine. ###Here are Mouser links for the 150K (http://www.mouser.com/index.cfm?handler=displayproduct&&lstdispproductid=479910) and the 470K (http://www.mouser.com/index.cfm?handler=displayproduct&&lstdispproductid=567616) parts. ###On DigiKey's site, see the QBK-ND series (http://info.digikey.com/T022/V5/0637.pdf) just below mid-page. ###Regarding the resistor in series with the optocoupler, no, it's a 4.7K in the picture. ###I moved one of the 100K's to R8.

gizz: ###Thanks!

******: ###Be sure and let us know how it turns out. ###I've always considered it too much bother to etch and drill a board unless I absolutely had to, but I always appreciate something easier or better. ###My circuit board technology is probably way out of date, though.

(Edited by Jon5ja at 4:55 pm on June 20, 2002)

[JoelM]

Jon,

I removed all the pieces from the ms20 board as your instructions say.
I am ready to start assembly as soon as my parts arrive.
I of course have a question though.

When I get ready to solder the new TLC27L4CN ###in place are there any special things I need to do? Like heat sink???

Thanks for all your help here.

Joel

[Jon5ja]

Hey, a prayer never hurts!

Joel, if you already removed all the requisite pieces, then you probably already know how to solder. ###If not, here's a link I found on one of Jesse's pages:
http://www.aaroncake.net/electronics/solder.htm

The biggest concern is that the TLC27L4CN chips can be easily destroyed by static electricity. ###Ideally, you should have your work laying on an antistatic (conductive, grounded) mat, and you should have a wrist strap to connect you to it (one designed for this purpose has a megohm resistor in series with the connection to ground -- please don't hook up a wire straight from ground to your wrist, and then touch a bare hot wire and electrocute yourself!). ###The soldering iron should also have a grounded tip hooked to the same setup.

That said... I didn't do that, although I was kinda careful, and I didn't blow up any of mine yet (but I have blown up lots of CMOS with static in my lifetime). ###Leave the chips in the tube or on the antistatic foam until you're ready to install them.

What I did was: pick up the MS20 board, pick up the tube (or conductive foam block) of chips, while still holding the board I remove one of the chips and stick it into the board (no chance yet for difference in potential to blow the chip). ###I then lay the board onto my work area. Normally there will be enough incidental pin tension to hold the chip onto the board until you can solder it; ###if it wants to fall out, you may have to bend a couple pins to make it stay in. ###Next, I'll touch a ground trace on the board with the soldering iron to equalize static, then I'll start soldering the pins to the board.

Never drag the chips around on a plastic surface. ###A wood work surface that's just been wiped with a damp cloth would probably improve your odds. ###Being barefoot might not hurt either! ###The static charge you see and feel when you walk across the carpet and touch a doorknob is many thousands of volts... to destroy one of these chips takes only a few TENS of volts.

If your soldering iron is hot and the tip is clean, it should only take about a second to solder each pin. ###I like very small diameter solder (the smaller the better). ###To make solder work, though, both parts being soldered have to be hot enough to melt the solder; ###you can't put solder on the soldering iron and "carry" it to the pins and expect it to make a good connection. ###Stick the soldering tip so it contacts the pin and the pad it's being soldered to for a second, and then feed the solder in at the junction where the pin, pad, and soldering tip meet. ###It doesn't take much solder to do the job.

That's all I can really think of that's really hasn't been mentioned... I've been trying to remember to post the static issue, but just now got around to it. ###If you're really scared, you can probably buy a 14-pin low-profile DIP socket and solder it to the board without worrying about static. ###Then, you can just plug the chip into the socket (watch the orientation), again holding both the board and the chip while plugging it in to avoid a difference in potential between you and the board.


(Edited by Jon5ja at 9:13 am on June 21, 2002)

[gantley]

JoelM

Jon said last night to treat the TLC27L4CN with TLC just as the part number states. ###Static can kill the little guy. ###He said make sure I am grounded to the board, ###then the chip package. ###Be as carefull and quick about placing the little guy in the socket. ###When i get ready to slober the cip on, touch one of the bound circuits with the soldering iron first. ###Jon has me about gun shy on handling the thing now.....lol

[Hill Hopper]

Since I'm somewhat of a clutz, I use chip sockets to solder in, and just plug in the chip. That way I don't smoke anything until I turn it on.

[Brian]

Great work Jon

I finally sent you a copy of my PIC stuff and I have added your link to your low power modifications to my manual.

Thanks again and keep up the good work.

[jayber]

Ok, I had a MS20 with Tinhorn's 3-wire setup + 10K resistor. ###I just modified the components to Jon's low-power configuration, minus the optocoupler. ###His modification manual shows 4-wires. ###Three seem straight forward, but where should the 'Switched Output "Ground"' go to? ###BTW, I also have 2-stage timer. ###So, should SOG go to 'ground' of the 2-stage board, somewhere else, or can it be eliminated? ###Any help would be appreciated.

[Jon5ja]

The intent was to totally isolate the camera from the MS20. ###If you want to do it the 3-wire way, you can just hook the green to the black (or jumper the board that where the green goes is hooked to the ground trace).

Really, if using a common ground is no problem (and I don't really see that it is), shouldn't we be able to just use an open-collector NPN transistor with the emitter grounded and the base driven also through a resistor from pin 14 just like Q4?

Or, for that matter, if there is no timer stuff added, just cut everything loose from the collector of Q4 and directly drive the camera shutter with Q4, shutter wires hooked to the collector and camera ground to the emitter?

Is there a reason I haven't thought about not to do this?

Arch? ###Brian? ###Tinhorn? ###Anybody? ###:-)

[JoelM]

Jon,

As soon as someone translates all of that to english I will answer you. : )

Thanks Again.

Joel

[Brian]

I am not tracking everything that is going on here buy you don't want to drive the shutter buttons with a transistor. ###You could damage the internal parts of the camera by injecting current into the system. ###The electronics see the closer by biasing some electronic part. ###If you use a transistor you will introduce current into the system and thus you could burn up the electronics. ###This is why an opto or relay works. ###They isolate the control from the internal trigger or workings of the camera.

If I am not tracking let me know.

[jayber]

Thanks Jon, I'll try jumpering 'green' @ L1 over to L3 and see if that works!

[jayber]

Green/L1 is 'Switched Output' by your instructions. ###Do I want to jumper it/L1 or White/L2, 'Switched Output "Ground"', to L3? ###I tried L1 & L3 and then L2 & L3 with no PIR response.

-------
Jon,
Just reread your e-mail and it sounds like I should go back to the 3-wire connections as they were before the mods plus jumper from L1 to L3. ###Is this correct?

(Edited by jayber at 2:48 pm on June 21, 2002)

-------
Switched it back to the way it was, but the LED won't ever go out now (?). ###With or without jumper from L1 to L3. ###Don't know what else to try.

Tinhorn (or anybody else),
Have you got the low-power mods to work with a 2-stage timer?

(Edited by jayber at 3:10 pm on June 21, 2002)

[Jon5ja]

The web page is/was wrong from what I can tell. ###I'm about to go change it. ###Looking at the pictures (I don't have the MS20 here) I'm fairly sure that Green is the "Switched Output Ground" ground and White is the "Switched Output" ... in fact, to test one last night, I'm almost positive I hooked the black and green together, and hooked an LED w/resistor from the +9V to the white wire and it would come one when the PIR was activated.

You might try that to see what's going on; ###if it'll light the LED but won't trip the camera, you may have to decrease the 4.7K down to 1K or so.

Incidentally, I've found components that were NOT soldered from the factory on several MS20s -- you might want to look and make sure there's nothing loose.

[jayber]

MS20 was working fine before the mods so I doubt it factory solder joints. ###I did try jumpering L1 to L3 just now and the LED still won't ever go out in TEST MODE.

-------
Might have to go back to 'original' since I'm using the 2-stage timer, huh?

(Edited by jayber at 3:18 pm on June 21, 2002)

[Jon5ja]

I should probably point out something, since the way I chose to wire things up was oblivious to the (now apparent) conventions that Tinhorn and/or others came up with.

The relay wiring, etc., shouldn't have to change if you're making the low-power mod but not replacing the relay with an opto. ###In fact, you probably shouldn't have to mess with your wiring even with the opto unless you have to swap the wires around.

Just replace the op amp chip, the Zener, and the resistors and you should be low-power.

[ArkansasElkHunter]

With no Opto L1 and L2 are dead for the timer mod version right. ###We jumper off the Pin 3 on the chip up to the circuit that L1 (only reason its abck in the circuit) is on and then through the 10k and out to the timer. ###

[Archilochus]

Hi Jon,
On the idea of connecting cam & timer grounds and using a simple NPN as the shutter switch.....
I seem to recall that Tinhorn tried that with some success on a cam model which I can't recall at the moment.

But there are a few 'non-technical' reasons that I'd caution against using or recommending that method.
There are several different camera models being used by people with a broad range of technical knowledge - from total beginner to advanced hobbyist, and even some professionals. ###The probability of someone hooking a part up wrong on the first attempt is very high (God knows I do it enough!! :-) ###With the cam & timer circuits totally isolated, the possibility of damaging either one by improper hook-up goes way down.
The other reason is all the different cams being used. ###At least one cam (and I suspect more) has a shutter that is triggered by pulling the 1/2 & full contacts to *positive* rather than ground. ###I don't know if pulling those contacts low would kill the cam - but I'm not up for finding out! ###:-0
Another reason is that the opto (or, to lesser degree, relay) is very cheap insurance. ###With the exception of major catastrophic failure (maybe a lightning stike?) - it is virtually impossible for the higher timer / PIR supply voltage to ever make its way into the cam. ###With a transistor there is always the unlikely, but not impossible, potential for a 'shorted' failure mode.

Archilochus

[gizz]

I performed the mods today and they work GREAT! This is huge for me cause those 1.2A 12V gel's where getting to be a pain. By calculation, leaving the 9V relay in and also running the LED when the relay is tripped should still give me close to 6 months(RUN TIME!) of battery life on a 9V alkaline. Less weight too!
You guys are the best!:bounce-aqua:

[Jon5ja]

Whew... thanks, gizz! ###I was beginning to wonder if I dreamed the whole thing :-) ###Several people are having trouble making it work.

I just did the mods on my Canon Owl PF/Date camera per Jesse's instructions (thanks Jesse!) on http://www.jesseshuntingpage.com/canon-owl-pf.html, hooked it up to the MS20 with the optocoupler, and it worked the first time!

I brought all three wires back to the MS20 in case I decide to do something different there later, but tied AF and Shutter wires together there. ###I did a little measuring in case anyone is interested, it might save someone else some time:

Open circuit voltage at the wires: ###3 volts
Voltage at point of triggering: ###1.5 volts
Maximum resistance to trigger: ###7.5K
Current required to trigger: ###200 uA
Current after flash/picture while wires held together: ###90 uA
Current transfer ratio of my PS2501-2 (sections combined): ###3.75

So, with my particular setup and these particular components, I should be able to increase the resistor in series with the opto to maybe 200K with these particular components at 9V supply. The 4.7K should be safe for anyone needing less than 5 mA to trigger.

Obviously, the controller in the camera is changing something once you take the pic, because the 200 uA required to trigger it drops to 90 uA until you release it.

I just took a picture of my kid when she walked into the room, so it works :-)

On the open collector transistor instead of an optocoupler: ###I'll buy Arch's argument that someone could hook it up wrong (or leave something connected to the collector) and blow up their camera, so I guess I'm convinced it shouldn't be the advertised way, ha. ###I wouldn't be scared to do it myself in a pinch, but perhaps it should fall into the "don't try this at home" category.

[ArkansasElkHunter]

Jon, ###I just finished my modification for the low power too. ###Everything works perfectly. ###My meter ###only goes to 0.1 mA so I cant measure the curent usage. ###The mods would have only taken me about 30 min except for my thick skull. ###I pounded it against the wall for three hours or so to thin it up a little. ###That and an email form you did the trick.

Something you might do for those of us that are not that bright would be to measure some voltages on the pins of the TLC and post them so we could tell if we fried the chip or not. ###The static thing really had me worried. ###That way we could know if the problem is there or somewhere else. ###I'd do it but I'm sure there is a particular pin that will be the tell.

[JoelM]

Jon,

I am gonna ask a couple of questions about these last few posts for my own clarification.

The instructions you wrote up had L1 and L2 reversed?

You have to wire your camera's with the 3 wire setup?

I should have my parts today and will try this setup tonight.

Thanks

Joel

[Jon5ja]

The original identification of which wire was the "Switched Output" and "Switched Output Ground" was switched. ###They are correct on the web page now.

Anyone who already has a working wiring scheme need not change it. ###If other devices such as one of Brian's controllers are connected, the wiring should be done per his instructions. ###The scheme described on the web page was one I arbitrarily chose to do on mine. ###As described on the page, connecting my green wire to the camera common and the white wire to the autofocus + shutter wires worked fine for me.

Jon


(Edited by Jon5ja at 2:55 pm on June 24, 2002)

[jayber]

Ok, I couldn't stand it! ###I ran home before lunch and got the MS20 I was working on last friday. ###To recap, I couldn't get it working with my 2-stage timer. ###Anyway, I changed the wiring back to Tinhorn's mods w/ 10K resistor and then replaced U1, R4, D4, R6, R7, and R8. ###It works now.....thanks to all that straightened me out!! ###:smile-big-blue:

[wfontjr]

jon
please explain switch output and switch output ground (in reference to the camera), i am building a new cam from the ground up with these new low power mods and modifying the internal timer, in the past i have always used a relay, with the relay i did not have to worry about which camera wire went where on the relay, with the optocoupler do i need to id the two wires out of the camera as to ground?

you guys are good but sometimes like honeywell, the same words for different things and different words for the same thing, LOL


(Edited by wfontjr at 7:25 pm on June 24, 2002)

[Jon5ja]

Maybe we should create a glossary and agree on terms... ###or... ###maybe that's already been done and I don't know about it, ha.

Probably the easiest way to decide is to hook your voltmeter (on a 10 to 30 volt scale) to the two wires out of the camera. ###When you get it so the meter is swinging positive (or indicating positive if it's a digital voltmeter) you know your meter red lead is connected to the camera's positive, and the meter's black lead is connected to the camera's negative.

Hook the camera POSITIVE to the L2 wire (my WHITE), hook the camera NEGATIVE to the L1 wire (my GREEN)

If all else fails, swap them around :-)

[MCinIL]

OK OK, now Ive heard it all. Swap them around? Huh. Sounds like us at work with rotation on motors. What next? ### ###

Just kiddn Jon. Thanks for all your input and help to the many here. I guess thanks to all who input info for others also. What a great place. MC.

[troll]

I knew there was a reason I bought an extra MS20 last year...Thanks Jon!

[wfontjr]

thanks jon,
now i waiting on the ups man's delivery from digkey,

[JoelM]

Jon,

Are you getting tired of the questions yet?

I hope not. ###You mentioned to watch the orientation of the TLC.

Do I also need to have the 14 pin socket oriented a particular direction?

Thanks again for all your help.

Joel

[Hill Hopper]

The socket is just a plug. Doesn't matter. However, it has a marking for the pin 1 end normally. Use it in that orientation so you don't get confused when pluging the chip in.

[Hill Hopper]

If anyone is interested, I'm planning on etching some small relay size boards for optos like I said I was liast weekend. Had to build a set of golf clubs for my daughter last weekend so I got delayed. Plan on doing some tomarrow or thurs. and will post some pictures. Not quite as cheap as Jons deadbug, but easier for me.

[Jon5ja]

Butch,

As soon as I get a chance I'm going to post a couple of alternatives to the way I wired the PS2501-2 originally. ###One of them is to wire the two output transistors in parallel, but with the emitter of one to the collector of the other -- that way it will not matter which way you hook it up to the camera.

I also have used a PS2501-1, which is a 4-pin single opto version, and it works fine too. ###The only real benefit of using the PS2501-2 like we did originally is you get twice the current capability (if you need it) for the same amount of drive current on the LED side... but mainly, that's the one I had so I used it.

I've taken some pictures but haven't updated the web page yet. ###I'm going to put the timer mods up first (hopefully tonight).

Jon

[Hill Hopper]

Jon, the -1 is what I'm planning on etching it for.

[Canuck]

Jon

Successfully modified several two and three wire cameras using the posted mods and leaving the existing relay (9V) in place everythng seems to be working fine.

This electronics thing is a little beyond me but I managed tomade it work anyways (Great Instructions). ###I was wanting to test the output of my converted sensors and was wondering at what points I should connect the meter. Please be as specific as possible in laymens terms so I can find the right points on the board or wiring, as I said most of this is well beyond me.

Thanks, and once agaiin great instructions, can't wait to see yo
ur timer/delay mods.

If you ever get to Alberta and want to get out hunting let me know!!

[JoelM]

Where do you put the wires for the LED after these mods??? I used to conect to pin 14 and ground but now I am not sure where to hook it.

Thanks

Joel

[Hill Hopper]

Here are some pics of the little board I etched for the opto and resistor. I used some scrap so it's not very square, but fits where the relay was.
http://community.webshots.com/album/41856164tnDEEc



(Edited by ****** at 5:20 pm on June 26, 2002)


(Edited by ****** at 7:41 pm on June 26, 2002)

[Jon5ja]

Canuck: ###Thanks, if I ever get that far North, I may just take you up on that! ###I'm working on some troubleshooting/testing steps for the power mods so hopefully I'll get that up soon. ###Here's a few quickies: ###with the meter negative lead connected to the battery ground, my prototypes read something like this:

Pin 1 is typically 0.865 volts below the battery voltage (+/- 0.1 probably)
Pin 2 is around 2.500 (+/- 0.03 volts or so)
Pin 3 is around 2.500, but your meter must be very high impedance or it'll skew the number
Pin 4 is battery voltage (- a few hundredths of a volt)
Pin 5 & 6 - probably too high impedance to measure with a normal meter; check pin 7 instead
Pin 7 same as Pin 2 (2.500 +/-) provided the PIR sensor is covered and allowed a few seconds to settle
Pin 8 is 0 volts when "inhibited" or no movement sensed; about 1.1 volts less than battery voltage when PIR is "seeing" something
Pin 9 & 10 - probably too high impedance; measure pin 8 instead
Pin 11 is the ground and should be at 0 volts
Pin 12 voltage varies depending on the charge on the internal timer capacitor
Pin 13 is about 1.32 volts
Pin 14 is 0 volts when the output is off, or about 1.1 volts less than battery voltage when the output is on.
Outside end of R8 should read 5.00 volts, (+/- 0.1 volts)

I'm just about done with the timer page, hopefully will get it done by morning.

JoelM: ###You should be able to do pretty much whatever you were doing before the mods with the LED. ###The TLC op amp might not have quite as much output current capability as the old LM324 did.

******: ###Cool -- I like it! ###Your next mission, should you choose to accept it, is to lay out the little timer circuit along with an opto so it'll fit in the "cleared" space on the MS20 :-)

Jon

[MCinIL]

Yes ******, your must accept. If not your cams will self destruct. Thanks for the pic of your mod. I may try this new thing, you guys call etching. I have never done it but who knows. It may come as addictive as ca bu9lding itself. MC.

[Hill Hopper]

There IS one draw back to etching. Right after I finished that little bugger, I knocked off my etch tank, which landed perfictly upright, but showered my muzzleloader with about 3-5 oz of etchant. Tried to get off but was too late. It now has a patchwork blued and rust brown finish. Probibly one of the most expensive / square cm boards around. Oh well, I didn't like the finish anyway. :shake-head-blue:

I'd be glad to see what I can work out. Shouldn't be too much of a problem. Jon, take a poll and find out what delays folks want on average and we can work out the resistor values. I'll start a new thread for a poll.

(Edited by ****** at 3:32 am on June 27, 2002)

[ArkansasElkHunter]

HH, ###I let an old TC rust up a bit one time. ###Got the bright idea to use Navel Jelly in the cleaning brush. ###Well Blueing turns out to just be another form of rust. ###I had a nice little cleaned area on the end of the barrel when I was through. ###

For those with a little interior rust you can't get rid of, this works great though if you duck tape the end of the barrel up really good (place flat over the end and cut out the hole with a razor knife) and go sparingly on the jelly. ###leave the nipple in and don't use enough so that it comes out the nipple. ###Use a brass brush and you will be ammazed at the shine inside the barrell. ###No more brown cleaning patches.

[Tinhorn]

That Navel Jelley is a good tip AEH. ###I sometimes wrap 0000 steel wool around a cleaning brush and swob out the barrel. ###Once I got a piece of the steel wool in my eye, didn't know it for several days and had to make a trip to ER in the middle of the night when it got infected or whatever it does..... ###I guess every thing has it's dangers

Tinhorn

[JoelM]

ok I had a recto crainal inversion last night ( head up my butt)

I didn't save or I lost the 4.7 resistor to put on the opto coupler.

Any ideas on what I could tear apart to get one?
And how the heck can I tell it is a 4.7 resistor???

Thanks

Joel

[Hill Hopper]

Check the color bands

[Jon5ja]

JoelM, ###just a note that the value of that resistor wasn't very critical in my setup (MS20/PS2501-2/OwlPF). ###Anything from 1K to 47K (or more) would've probably worked in my case. ###If you're near a Radio Shack, I'm sure they've got a little pack of five 4.7K or maybe 10K resistors that should do fine. (Don't leave off the K or you've got a thousand times less resistance :-)

[wfontjr]

jon
can the hot wire for the board be soldered in the empty hole from the banded side of d2 or does it have to go on r4/q1, aslo if i have the hot from previous mods on the banded side of d1 is it ok to leave it there

[Jon5ja]

wfontjr,

Yes, you could put the hot wire on the D2 banded-end hole, or if you're not using a relay you could use the D1 banded-end hole. ###In fact, I would've probably done that if I weren't still experimenting. ###I had a timer built that was set up to use the D2 hole so that's why I didn't use it for power. I left D1 in because I'm not sure I'll never put a relay back in for experimentation, but it does make the wiring cleaner to use the D1 holes.

If you're going to use a 9V battery, you could leave D2 in place and feed the hot to the R3 hole nearest D2 and have reverse-polarity protection. ###There's too much total forward drop to do that (and still have 5V regulated) if you're running it off 6V. ###I'm a little nervous about not having any reverse-polarity protection because probably if you just touched the battery to the connector backwards, the chip would be fried.

[Tinhorn]

When running the unit on 6volts, you can add a 1 amp (or bigger) diode (1N400X) across the power leads at the board somewhere handy with the Kathode (banded end) attached to the batt (+) wire. ###It would be better if you had about a quarter amp, inline, ###fast blow fuse in the batt (+) lead when doing this. ###If the battery is accidentaly hooked up backwards, it'll blow out the fuse, if you have one but even if you don't, if the battery is only connected momentarily, the diode will probably handle the battery current ok for a short amount of time. ###If you leave the battery connected too long, it'll blow the diode (hopefully short it and not burn it open) ### better than nothing

Tinhorn

[wfontjr]

thanks jon
success on the low power modifications, i got to buy a new meter tommorrow, i can only tell its an order of magnitude less with this old meter, any recommendations on a radio shack meter model

(Edited by wfontjr at 7:42 pm on June 27, 2002)

[Jon5ja]

I agree with Tinhorn 100% regarding the diode.

wfontjr, I hate to make a recommendation without any experience with the meters, but looking at RS's web page, looks like the minimum for me would be the Model 22-811 (http://www.radioshack.com/product.asp?catalog%5Fname=CTLG&category%5Fname=CTLG%5F008%5F002%5F001%5F000&product%5Fid=22%2D811) which is about $50. ###Most of the higher-priced ones look like they'd be OK, I guess it depends on how many luxury (or frivolous) features you could use.

Maybe some of the other guys reading this thread have some experience and can chime in.

Jon

[Hill Hopper]

I have a 22-811, and it works great.

[Ganewbie]

You guys are incredible. I have only been her about a week and I already know more about sensors than I ever thought possible. I've searched on my own for a less expensive alternative to the Radio Shack Motion Detector. I've read all the posts on new sensors and keep coming back to this one. For the money, I don't think it can be beat???? I have one big problem. I don't understand all the electrical jargon. Is there a step by step in writing for changing this motion detector. I need help straight from the box. Part numbers, where to get the parts, how to remove the old ones, how to install the new ones, someone to hold my hand.... Sorry I got carried away. Just three words.

I NEED HELP!!!

:skeered::skeered::skeered:

[wfontjr]

check the previous pages, jon has a link to the directions in one his replies

[Ganewbie]

bring to front

[wisbowhunter]

i thought i would try the low power mods but i don't get any pictures i just get the words could someone help me out?

[Jon5ja]

I don't know why, but some people have trouble seeing the pictures in the page. ###Here are links to the individual pictures, so maybe that'll help:

Picture 1 (http://people.txucom.net/srbarclay/LowPower_files/image001.jpg)
<a href="http://people.txucom.net/srbarclay/LowPower_files/image002.jpg" target="_blank">Picture 2
</a><a href="http://people.txucom.net/srbarclay/LowPower_files/image003.jpg" target="_blank">Picture 3
</a><a href="http://people.txucom.net/srbarclay/LowPower_files/image004.jpg" target="_blank">Picture 4
</a><a href="http://people.txucom.net/srbarclay/LowPower_files/image005.jpg" target="_blank">Picture 5
</a><a href="http://people.txucom.net/srbarclay/LowPower_files/image006.jpg" target="_blank">Picture 6
</a>Picture 7 (http://people.txucom.net/srbarclay/LowPower_files/image007.jpg)

[wisbowhunter]

thanks

[wfontjr]

i had the same problems with the pictures, copy and paste the article into word and the pictures will be there

[gtk]

Where do you get the parts for this mod ? ###I have been to 3 radio shacks and found nothing ###that looks close....

TIA.

[jayber]

I got my parts form Digi-Key (www.digikey.com / 800-digikey) as Jon5ja suggested.

[passgas55]

******

[Hill Hopper]

Mouser also has them. www.mouser.com

[passgas55]

bring to top

[Dbworld]

Moving back to the top

[bradleydale]

Hey guys,

First let me say thanks a bunch for the expertise here..Just got done completing my first low power mods and works super!! One question I have is how to wire up an LED with this. I played around with this but the light always stayed on.....ummmm, I think I just answered my question. I probably wasn&#39;t giving it time to reset since I was doing this by holding bare wires to areas on the board....

Any ideas on how long it takes for the coupler thing to reset before switching the camera on?? No noticeable click like with the relay before!

Thanks again for the info!

Brad

[passgas55]

I did 2 lp ms20s and one was set up just to trigger brians&#39; chip so no optical was used. The other was set up to be used on an owl pf with the ms20 version of a timer. How is yours set up? Remember that it takes about a min. for warm up which keeps the optical fired the whole time. Mine on test it fires for 4 seconds and until all movement is stopped and on auto it fires for about 6 seconds then times out about 2.5 min(adjustable).All these times varies to some degree. That is the times on the owl pf setup. If you are trying to check times with out the pir lens in place you won&#39;t get a good test.

[bradleydale]

Thanks,

It seems to be working great now...I just don&#39;t have the audible click of the old relay to tell me when it is safe to switch the camera on. This will soon be eliminated once I get an LED hooked back up..or thats the plan. This setup is a Polaroid 2400 and MS20 without a timer, etc.

I do have another question, I have started modifying another ms20 board the same way. When setting up the opto coupler to replace the 9volt relay, how can you tell which one is pin #1?????

I was in a hurry to complete this second one and did not get something quite right..I figure its either one of two things, the optocoupler comes to mind first since you have a 50/50 shot at being right or wrong on pin #1.

Brad

[jayber]

bradleydale,

Are you referring to using a PS2501-2 dual optocoupler? If so, have you checked out Jon5ja&#39;s Low Power Mods (http://people.txucom.net/srbarclay/LowPower.htm)? It explains and illustrates where pin #1 is. In the top left pic of the set it&#39;s the lower left pin with the small indicator mark next to it. Hope this better explains it and good luck!

[bradleydale]

Thank you once again....as someone else mentioned, I was having one of those rectal cranial inversions...Had I not look, I would have argued that there was no mark near pin #1..but there it is. Like I said, this was my second sensor modification..the first worked fine which means luck was just with me on wiring. Not so on the second sensor...going to correct now!

Thanks

[Old One Horn]

I just did the low power mod. without a hitch. Awsome posting !! This will be my first two homemade cameras. I am going to trigger a Samsung 33S. By the way, I did tie output ground to common as per the earlier postings and it worked like a champ as well. Can&#39;t wait to get it finished in the case and put it to use. I also have a question about the fresnal lens. Did anybody mask off parts of it to narrow the effective angle ? Was it necessary for better centering in the picture or to avoid false trips from squirrels on the ground, etc? http://www.jesseshunting.com/forums/style_emoticons/<#EMO_DIR#>/smiley-faces-toast-beers.gif

[#GO#-HUNT]

Lil help please,Ive been using the 6-volt gel batteries and would like to add the power mods and change to the 9-volt power supply and still use the 5-volt relays.Does anyone have a pic or can tell me what to do to here.I know ive read about adding a resisiter (or something) .Thanx guys http://www.jesseshunting.com/forums/style_emoticons/<#EMO_DIR#>/smiley-banghead-yellow.gif

[Jon5ja]

The relay will draw considerable current and won&#39;t let you run the 9-volt battery down nearly as far before it starts misbehaving as would an optocoupler, but you can use the relay and it&#39;ll work for a while (since most of the time it&#39;s not actually powering the relay anyway).

Which exact relay are you using? Do you know how much current it draws?

If you know the relay current, you can add a resistor in series with one of the relay coil leads. If you don&#39;t know the relay&#39;s current, you can measure the resistance of the relay coil, and divide 5 volts by that number to come up with the current (in amps, like 0.015 or something).

To calculate the value of the series resistor, you can divide the excess voltage (4 volts in this case) by the amount of relay current. For instance, if the relay draws 15 mA, that&#39;s 0.015 amps, so 4 divided by 0.015 = 266.7 ohms, so I&#39;d round that to the nearest standard value, which would be 270 ohms. Here&#39;s a little chart depending on the current the relay requires. I used the same value for 30 and 35 mA because it worked out to the same nearest standard value:

5 mA -- 820 ohms
10 mA -- 390 ohms
15 mA -- 270 ohms
20 mA -- 220 ohms
25 mA -- 150 ohms
30 mA -- 120 ohms
35 mA -- 120 ohms
40 mA -- 100 ohms
45 mA -- 82 ohms

Jon

[ArkansasElkHunter]

can&#39;t get mouser of Jameco to recognize the "LM385Z-2.5NS" part #. Seems like it took a while to find it last time too. Anybody know the mouser part#

[Jon5ja]

The LM385Z-2.5NS part is what Digi-Key uses as their part number (the NS on the end just means National Semiconductor). On Jameco&#39;s site, just search for LM385Z-2.5 in a "keyword" search. Mouser doesn&#39;t carry these parts as far as I can tell.

[#GO#-HUNT]

Jon,
I would be using the 5VDC REED Relay from RS (#275-232).It states on the box its rated 1 amp at 125VAC.From earlier posts,i noticed people refering to 9-volt systems lasting 4-8 months.What estimated time frame could i get using the relay?
Just to let you know,I whole-heartedly appreciate all the testing and messing you do for everyone here.Simple folks like myself would never know where to start.


Anddddd,After purchasing a game camera at a local store(and returning it after getting 2 complete rolls of false pics),I then set out to build my own.First pics from my homebrew got me turkeys and a raccoon,BUT NO FALSIES........I&#39;ll never buy another,Its Jesse&#39;s for LIFE. http://www.jesseshunting.com/forums/style_emoticons/<#EMO_DIR#>/smiley-bowdown-purple.gif


I just fell back reading and noticed a nice big picture showing a 9-vt RS setup using a 5vt reed relay with a silver banded diode(RS#276-1101A).Is this what I need? Thanx........ http://www.jesseshunting.com/forums/style_emoticons/<#EMO_DIR#>/smiley-banghead-yellow.gif

[Jon5ja]

The 275-232 draws 20 mA, so per the chart above, you&#39;d need to put a 220-ohm resistor in series with it to run it off 9 volts.

I really don&#39;t know how long it&#39;ll run with the relay -- what will limit your battery life is the fact that, eventually, the battery can&#39;t deliver enough current to drive the relay without the voltage dropping below 5.4 or whatever point at which the internal circuitry goes unregulated... then, it&#39;ll do what Tinhorn and others have reported -- it&#39;ll sit there and rip off the rest of the film in your camera and oscillate until it finishes off the battery. I&#39;d still expect it to last months, though, if it wasn&#39;t taking a large number of pictures per day.

If you didn&#39;t remove the silver-banded diode that is already on the MS20 circuit board (beside the original relay), then you don&#39;t need to add another one -- that one will still serve the purpose of blocking the "kick-back" from the relay.

Congrats on your success with the homebrew cam!

To Old One Horn, if you&#39;re reading this:

I think most people have to mask off the Fresnel lens to narrow the field of vision if they leave the MS20 in the original housing.

Many people flatten out the plastic lens, which inherently narrows the range because only the stuff from nearly directly in front of the sensor exactly focuses on the PIR element. Stuff farther off center has to be lots closer to trigger, so I guess it all works out.

[Old One Horn]

I&#39;ll try taping some off since I kept it in the original housing. I guess it will be some trial and error. Thanks for the info. I did the full low power mod. including the optocoupler and everything works great !!!!!

[#GO#-HUNT]

Jon,
Quick question please........
After checking my TLC27L4CN for voltages,everything seemed ok except pin 8.
As stated,it read 0.0 with no motion.......With motion detected,it would only show voltage for a split milli-second(thats what it seemed like) before going back to 0.0 even though it wa still tripped from detecting motion.Is this correct?
Thanks

[Jon5ja]

#GO#-HUNT, that&#39;s sounds normal. I&#39;d actually expect it to be a few tens of milliseconds, but I haven&#39;t measured it. If you were constantly triggering it, you should approach the point at which pin 8 would stay high constantly (but not quite).

[didntseeany]

Can I leave my relay in the K1 slot and still get the benefits of the low power mods?
I&#39;m a total moron when it comes to electronics and the optocoupler looks a bit difficult.

[Jon5ja]

Yes, if you have it working with a relay already and don&#39;t want to mess with that part, just change the 4 resistors, replace the Zener diode with the LM385Z-2.5, and replace the LM324 chip with the TLC27L4 and you should be set.

[hunt4it44]

I am about to embark on building my first cam (Owl PF is in the mail and PIR WM2 is in the garage). After reviewing all of these absolutely incredible posts and instructions on Jesse&#39;s Hunting Page, I am going to attempt to modify the WM2 with the instructions on Jesse&#39;s Hunting page ("How to Modify the Regen MS20W, MS20C and MS20B PIR Motion Detector Spotlight Unit") and Jon&#39;s "MS20 / WM2 Simple Timer Addition". I don&#39;t know if I am brave enough to try the low power mod&#39;s discussed on this forum. Specifically, based on my past soldering experiance, replacing the LM324N with TLC27L4CN could easily turn into a nightmare. My question to the experts are:

1) Are there any benefits to making all the power mods except replacing LM324N or are the changes dependant on this replacement?

2) I intend to use a rechargeable 6volt gel battery with a solar panel to run my cam. I would think this would provide a reliable voltage source. With this in mind, are the power mods worth the effort?

3) If I do not make the power mod&#39;s, can I still use the PS2501-2 instead of a mechanical relay? And if I can, do you know what size resistor I would need to use (the one attached to pin 4) considering I will have a 6 volt circuit?

Thanks in advance for your help.

[Jon5ja]

hunt4it44,

1.) It&#39;s probably not worth doing the mod without replacing the LM324 -- it draws more than half the current.

2.) Yes, a gel-cell and a solar panel will provide plenty of power. But, if you do the low-power mod, a 9V battery will be much cheaper/neater. In fact, it&#39;d be a lot cheaper to pay someone to modify an MS20 for you than to run a gel-cell and solar panel.

3.) Yes, you can still use the opto. The 4.7K is probably still OK for 6V, since some are using 10K with 9V or less. Originally, I was using the PS2501-2 because I had a handful of them. Lately, I&#39;ve been using PS2501-1 because they only have 4 leads and are easier to wire. Using the PS2501-1, pin 1 is the same; pin 2 connects to the resistor; pins 3 and 4 connect to the camera, 3 to camera ground and 4 to the shutter/refresh wires.

I&#39;d bite the bullet and do the low-power mod. Find a friend/neighbor/ham radio operator that can replace the chip for you. Or, go to Radio Shack and buy a $10 desoldering iron (Catalog # 64-2060), practice a bit with it, and you can unsolder that chip in about 30 seconds.

[didntseeany]

I bought some resistors today and I&#39;m not sure they are right. I got a pack of 100k-Ohm resistors-1.2 watt, 470-Ohm-1/2 watt, and 150-Ohm 1/2 watt. They were bigger than the ones on my ms20 board. Are these the wrong ones and what should I look for if they are? Keep in mind I&#39;m an electronics idiot.

[Jon5ja]

If you can physically fit 1/2-watt resistors in to the space they&#39;ll work fine, but I normally use 1/4-watt resistors; 1/8 watt resistors will work, too.

Now... regarding the values: those "K&#39;s" on the value are important. If you got 470-ohm and 150-ohm resistors instead of 470K and 150K units, you&#39;re off by a factor of 1000! If you really did get 470K&#39;s and 150K&#39;s, the determining factor will be whether you can physically fit them in the space.

[didntseeany]

Ok I did the low power mods and left my 9 vdc relay in the k1 slot. Now I hear that audible click when I plug the battery in but thats it. Is this normal and how can I tell if its working because I don&#39;t have my camera fixed up yet.

[Jon5ja]

It&#39;s normal for it click as it cycles on and off for the first minute or so. Then, it should quit clicking until it senses motion. This should be no different with or without the low power mods.

[didntseeany]

Uh oh ,then its screwed up. After it warms up it just clicks and clicks and clicks non stop.

[hunt4it44]

Jon5ja

Many, many, many thanks for your encouragement on making the low power mods to my MS20. I had previously posted that I was concerned that my limited soldering skills would make a mess of changing out the LM324. However, just the opposite occured and things went without a hitch. I also used your suggestion to use the PS2501-1.

Here is the amazing part - This is my first attempt at making a cam - I did the lower power mods, the timer mods, wired the camera and the test LED - and the darn thing actually works!!!! I still need to mount my camera in the case, but when I hook it up to the MS20, and had my kids parade around in front of it, it worked like a charm.

To all those out there who are questioning whether you can build this project - YOU CAN DO IT. I researched these boards, downloaded great step-by-step instructions and it is actually quite easy. My total cost using a Canon Owl PF and MS20 is around $60 (not counting the enclosure which I already had).

Many thanks to all who have posted their great advice on this forum.

[SIO]

Thanks for all the help earlyer but im still having problems... Modified 2 more MS20&#39;s with the low power mods and i have one with 9 volts on R8, 0 volts on pin 1 of U1... I swapped the IC, LM385Z, Q1 and serched til my eyes where sore for a short but no change... The rest of the pins on the IC seem to have the correct values except for pin 14 witch has a steady 8.5 volts... The other unit has all the correct values but continues to power up pin 8 & 14 at uneven times non stop... Please help been trouble shooting them for over a week.

[Jon5ja]

SIO, I made the following suggestions to someone else who was having problems, but thought I&#39;d post them here in case you didn&#39;t see the post. I&#39;d try replacing the components in one step-by-step to see if you can figure out where the problem is creeping in. Here&#39;s what I&#39;d do:

First, get the MS20 working the way you want it BEFORE you do the low power mods... make sure it triggers the camera, etc., and doesn&#39;t oscillate; test it in the same way (i.e. in the housing, or not) before you do the low power mods as you will once the mods are done.

Second, after everything is working to suit you, replace just the LM324 chip with the TLC27L4CN chip. Test it, and everything should be working just as it was originally. If it&#39;s not, you either have a bad (or killed) chip or a solder bridge.

Third, replace D4 with the LM385Z-2.5. If it doesn&#39;t work now, you&#39;ve either got a dead or miswired LM385 or a solder bridge.

Fourth, replace R8 with a 100K resistor (Brown-Black-Yellow-Gold). If it doesn&#39;t work now, look for a solder bridge. It is slightly possible (though I&#39;ve neve seen it) that if you had a sick (damaged) TLC27L4CN it MIGHT work with the factory value for R8 but not with the 100K substitute, but I&#39;d give this a <1% chance. I&#39;d give it another <1% chance that the LM385 was flaky and would work with the factory R8 but not with a 100K.

Fifth, replace R6 and R7 with 470K resistors. If it doesn&#39;t work now, look for a solder bridge. Also, there&#39;s a slight chance that a sick TLC27L4CN might work with factory R6 & R7 but not with the new values, but it&#39;s very unlikely.

Sixth, if it&#39;s still working this far, change R4 to 150K. If it doesn&#39;t work now, look for a solder bridge. There is a slight possibility that a flaky TLC27L4CN might cause a problem when R4 is increased to 150K but it&#39;s unlikely. Also, a leaky Q1 is a possiblilty, but unlikely.

If you follow these steps and test along the way, you&#39;ll almost certainly find where the problem creeps in.

Good luck!
Jon

[Rooter]

I am really interested in trying this power reduction mod, but I prefer to go to Radio Shack to order my parts. Has anyone put together a Radio Shack parts listing so that I can walk in and pull the parts rather than order them from digi-key?

Thanks,

Rooter

[Nytro69]

ditto on the radio shack part numbers for me just easier to shop near home.

[Jon5ja]

Sorry, but it ain&#39;t that easy :-) Radio Shack might be able to order the parts for you, but I expect you&#39;d pay a lot more for them than getting them from one of the indicated sources, and you&#39;d have to wait anyway.

Of the places from which I commonly order parts, Digi-Key is the only one (as far as I know) that carries all of the necessary components.

Mouser carries everything but the LM385Z-2.5.
Jameco carries the LM385Z-2.5, but not the TLC27L4 or TS27L4 op amp chip.
JDR Microdevices also carries the LM385Z-2.5, but not the op amp chip.

I&#39;m sure some of the larger distributors would have everything, but I&#39;m not sure it&#39;d be more economically feasible in small quantities than the suppliers mentioned above.

If you can wait until January, ****** should be back open and will be your best bet.

[SIO]

Thanks Jon, for the advise and the off I may take you up on that. I don&#39;t understand how my first one now works & the second 2 dosen&#39;t. But i fixing to try what you told me to do to trouble shoot. I had already swapped out the extra resistors R4, R6, R7 and it still doing the same. Sometimes it will go 3-4 minutes and then fire off several times just very unstable. Im just monitoring Pin 14 on the IC when testing them I guess this is OK. Also can the opto couplers handle 12 volts cause I&#39;ve got 2 of them that are out now.

Thanks again

[Jon5ja]

SIO,

The optos shouldn&#39;t be concerned with what voltage you&#39;re running the system from as long as the current to them is limited to less than 50 mA. With 12 volts and a 4.7K resistor in series with the LED half of the opto, they&#39;d be seeing only about 2.5 mA.

You ARE using 4.7K (that&#39;s 4700 ohms) resistors and not 4.7 ohm resistors, right? Yellow-Violet-Red-Gold is 4.7K and what you want.

[wtailp&y]

Just wanted to say thanks. Completed my second cam the first one was using a fieldpix board (works great) the second one is the MS20 with jons power reduction mods. Right now i am experimenting with taping off the fresnal in the basement. I think my labs are getting tired of getting their pictures taken. thanks again

[hilljec]

Could you just clip out all that isn&#39;t needed as shown and still leave the 3 parts that you replaced? Would this still get you any power reduction without replacing any parts, but just clipping others out? http://www.jesseshunting.com/forums/style_emoticons/<#EMO_DIR#>/smiley-bag-on-head.gif

[Jon5ja]

Most of the stuff removed has to do with the 120-volt circuitry. Mainly, we&#39;re just getting that stuff out of the way. About 1 mA is being drawn by the LM324 op-amp chip, and most of the remain 0.6 mA is being drawn by the voltage regulator circuit (the zener diode and its pull-up resistor).

Sorry, but clipping out the other stuff isn&#39;t going to help much.

[Otto]

MS20 low power mod simple wiring diagram for canon owl with SPST & DPDT switches.
Check Ammo Can album on webshots page.

Change value of r-26 for different delays with switch in test position.
220K = about 10 seconds I believe.

[t-may]

Where can I find the ms20 motion sensor. I have been to Wal-mart and they have change brand, Lowes don&#39;t have
it in the Regent model. And thanks for all the help on this
site you guys rock, on this camera stuff. I have 2 home made camera now and I would like to try the new low power ms20 model.