M1/M3 IR power pack

Would any one know ho repairs the M3 Infrared sniper scope power pack. I think the one I have was rebuild in the 80's & uses a 6 volt battery. It has a small problem. You turn the power pack only on & not to long after it blows a 10-A fuse . I did have the scope on a carbine & squeeze the IR trigger had a green light & heat from the light filter & not long after it blows a fuse. Thanks for any info.

https://www.milsurps.com/images/impo...yp70bhn4-1.jpg
https://www.milsurps.com/images/impo...qdmyipfx-1.jpg
https://www.milsurps.com/images/impo...elstndwo-1.jpg

These things split the power from the battery into two paths . There is the one path that goes into the do-dad ( technical term ) that boosts it up to 30,000 volts (IIRC) to run the scope . The 2nd path remains at 6 volts and powers only the light . Does the 10 amp fuse protect both , first only , or second only ? If it does both or first only , I would not up it as damage may result . If it covers the light only , you might try upping it to a 12 or 15 amp and see if that cures it . The wires are pushing 70 , and may be corroded inside or wearing or have a short . Upping it a little prob'ly won't start a fire or melt the cables , but other than a cable replacement or ripping it apart , I don't see much else to do .
Chris

I had an electronics guy work on mine. He came to see me , saw it and took it home. He re engineered it to
work better than original, in his opinion...lol But it does

Quote:

---

Originally Posted by can14

I had an electronics guy work on mine. He came to see me , saw it and took it home. He re engineered it to
work better than original, in his opinion...lol But it does

---

Can14 Will probably do the same if I can find one. Does or did the inside of you power pack look like the one I have ???

you are missing parts. the transformer also looks like it has seen better days

https://www.milsurps.com/images/impo...plastics-1.jpg

your missing the plastic parts. in the base goes two rectifier tubes. and the high voltage output is the thin tube. the cups goes over the tubes to hold them in place.

Will see if I can get an actual picture tomorrow.

If you look at the transformer you should see two sets of wire which are probably cut back. A yellow set and a blue set.

The biggest mistake people make is powering up the unit without the scope attached. The high voltage seeks a ground and over heats and fries the spring which transfers the high voltage from tubes to high voltage cable that powers the scope

new2brass
I think my power pack was converted at one time. I don't think I could find the parts to bring it back to original. I did find a elderly gentleman that still works in old Electronic stuff. He spotted a broken part & a cable missing right off the bat said he can fix that & he will see what he can do to get it going. I gave him some info on how it works, a repo manual & the hole kit scope,power pack & cables. I got my fingers cross .

Quote:

---

Originally Posted by gunsdora

Would any one know ho repairs the M3 Infrared sniper scope power pack. I think the one I have was rebuild in the 80's & uses a 6 volt battery. It has a small problem. You turn the power pack only on & not to long after it blows a 10-A fuse . I did have the scope on a carbine & squeeze the IR trigger had a green light & heat from the light filter & not long after it blows a fuse. Thanks for any info.

https://www.milsurps.com/images/impo...yp70bhn4-1.jpg
https://www.milsurps.com/images/impo...qdmyipfx-1.jpg
https://www.milsurps.com/images/impo...elstndwo-1.jpg

---

Does any one know if there is some one ho re-builds this power packs. The guy here cant repair the one I have. Not sure if it is worth repairing .