Magnum S-380 Need picture of the bottom side of board

[Crossbow]

711,
Your advice was great and put me in the right direction. After talking to a friend on the phone that had worked on these type of radio's before and swore off ever taking another one in his shop for repair told me what to look for and once I found the area giving me the problem from not only a voltage loss but a very wrong voltage from the problem area sending it to the PLL that even blew my friends mind as he had never seen that happen. Not only was the coil bad but lack of voltage from the place they had jumped the board from plus took out a couple caps as well.

I agree with not many have worked on this type of radio but I bet you there is one or two that have!

Like I said it would have been a great conversation to figure it out together that would have helped anyone else that might come across one of these radio's one day with the same type of problem.

 

[711]

I think every radio has its own uniques difference about it as do each fault or failure. VCO and PLL is some tricky spots to trouble shoot. I had this Lafayette that would never tune , I narrow it down to a sealed VCO circuit in a metal box. They decided to sealed the whole circuit in epoxy. The part is obsolete and I believe I know the fix but these things never make sense . Glad you got it going. Good job bro

 

[nomadradio]

There will be a number printed on the VCO module, typically. A search on Fleabay for that number may turn up a replacement.

A guy in England makes replacements. Just the naked VCO circuit board, but with pins in the right spots to line up where the old one was mounted.

I'm not an expert on all the different variations, but the ones I have bought from him to fix old Midland, GE and other radios have all worked just fine.

73

 

[711]

There will be a number printed on the VCO module, typically. A search on Fleabay for that number may turn up a replacement.

A guy in England makes replacements. Just the naked VCO circuit board, but with pins in the right spots to line up where the old one was mounted.

I'm not an expert on all the different variations, but the ones I have bought from him to fix old Midland, GE and other radios have all worked just fine.

73

Nomad,
If that wasn't for me disregard it if it was , normally the part in the sealed circuit that goes bad is an electrolytic cap. On the epoxy, a trick I did in the navy was lower the temperature on my soldering iron to around 170-200 degrees to slightly overcure the epoxy, what happens is it just starts to flake into dust and you can just carver your way down to your part. If that part isn't the fault, I might have to look that guy up.

 

[TM86]

There will be a number printed on the VCO module, typically. A search on Fleabay for that number may turn up a replacement.

A guy in England makes replacements. Just the naked VCO circuit board, but with pins in the right spots to line up where the old one was mounted.

I'm not an expert on all the different variations, but the ones I have bought from him to fix old Midland, GE and other radios have all worked just fine.

73

Just an idle curiosity question. Do you install those boards as is, or do you epoxy/silicone them in the same general manner as the originals for thermal stability?