ER Mag OCT 2011 BC-224 repairs - the broken capacitor could be repaired.

[Opcom]

The broken cap there suffers from the same fate as many others of the same construction. The retaining ring cracks and the spring loaded plates short.

here is how to fix it.
http://bunkerofdoom.com/cap/fix1/index.html

There is no need to replace it with a hard to find substitute when it can be kept original.

[KA2DZT]

I have  a lot of those small caps, just in case.

Fred

[Opcom]

If you have enough, now would be the time for an ER ad! But repairing the cap and putting that beautiful old mobile radio conversion back on the air was very gratifying.

[k4kyv]

The broken cap there suffers from the same fate as many others of the same construction. The retaining ring cracks and the spring loaded plates short.

here is how to fix it.
http://bunkerofdoom.com/cap/fix1/index.html

There is no need to replace it with a hard to find substitute when it can be kept original.

That's why I never throw anything away if it's still good.  I have a cigar box full of those caps, of various capacitances and by various manufacturers.  If I couldn't find an identical replacement, I could probably part out one for the unobtanium hardware and repair the original.  I have maybe used a half dozen of them in the past 30 years, but they are there if I ever need one.  I used some in the Gates crystal oscillator conversion.

[K5UJ]

The broken cap there suffers from the same fate as many others of the same construction. The retaining ring cracks and the spring loaded plates short.

here is how to fix it.
http://bunkerofdoom.com/cap/fix1/index.html

There is no need to replace it with a hard to find substitute when it can be kept original.

Since the error is in ER, why write about it here?  Probably lots of ER readers don't even look at this.  I recommend you send a letter or email to Ray Osterwald at ER informing him.  He'll probably run it in a letters to the editor column.  If ER is wrong, it is important that a correction appear in ER as a matter of record.

[Opcom]

Its not really an error or, to be more precise, I do not consider it to be an error. I suppose the author did not consider the capacitor repairable in his opinion. His article his opinion.

I did send an e-mail to the editor and I hope he will include it next time to the benefit of those with that general kind of radio.

I posted it here because not everyone reads ER, and of those that do not read it but have that kind of radio set or the similar type listed in the article, not so many know how to fix that kind of cap and would be in the same unpleasant situation as the author having to make an annoying substitution in a restored set. If it is troubling to have things like this posted here I will try to avoid doing that in the future as it does not make so much difference at this end.

[WB6NVH]

Sorry to be a troublemaker but that GE radio in your article is a Progress Line strip.  Mastr II dates from 1970+ and is all solid state.

[Opcom]

Thanks for that information on Progress Line. I didn't know other than what the guy that gave it to me said. No manuals, etc.

[WB6NVH]

A brief overview of Progress Line gear is on my GE Mobile Radio History page here:

http://www.wb6nvh.com/GE/GEhist1.htm

I have fixed those capacitors by swiping a good collar from a junkbox capacitor, but that means having a decent junkbox! 

[The Slab Bacon]

Patrick,
           I have run into that same problem on many radios. I use a small vise to re-center up the plates, but................. There is enough tension on that pressed nut (remember that it is PRESSED on) that I just wouldn't trust epoxy to make for a long lasting repair.

If you can slobber it back together that would be the ideal way to go, but that is very hard to do. I use a small vise to re-center the plates up, drill a small hole all of the way through the nut and shaft, and drive a small roll pin through the whole shebang. This will last forever.

I had to do 10 of them in my old navy RBS receiver. What a PITA! !

[Opcom]

I didn't consider solder, that's a great idea if the shaft will take it! The nut on mine was brass.

[The Slab Bacon]

I didn't consider solder, that's a great idea if the shaft will take it! The nut on mine was brass.

Patrick,
           they are all brass, just chrome or nickle plated. The roll pin really works well, they'll never slip again. All the work on that RBS of mine, I had to dissassemble all of the coil catacomb boxes, as well as most of the IF cans.

After thinking I was smart, and completely recapping that RX before putting the juice to it, I figgered in advance that I had it licked. But................... As soon as I put the juice to it, I had resistors everywhere letting the magic smoke out. I wuz not a happy camper, but I just bit the bullet and fixed it. The more I dug around, the more bad ones I found.

I guess some of them must have used some kind of crappy low-grade brass, and/or the original press-fit was just too tight. They all split on the flat side of the "nut".

[w1vtp]

I wonder if any of these units had this failure during WW2 - in the heat of battle!

[Opcom]

I didn't consider solder, that's a great idea if the shaft will take it! The nut on mine was brass.

Patrick,
           they are all brass, just chrome or nickle plated. The roll pin really works well, they'll never slip again. All the work on that RBS of mine, I had to dissassemble all of the coil catacomb boxes, as well as most of the IF cans.

After thinking I was smart, and completely recapping that RX before putting the juice to it, I figgered in advance that I had it licked. But................... As soon as I put the juice to it, I had resistors everywhere letting the magic smoke out. I wuz not a happy camper, but I just bit the bullet and fixed it. The more I dug around, the more bad ones I found.

I guess some of them must have used some kind of crappy low-grade brass, and/or the original press-fit was just too tight. They all split on the flat side of the "nut".

I missed the "roll pin" idea. What do you mean, a pin put through a drilled hole in the shaft and 'nut'? - I don't have the precision tools to do that. Or maybe I should think about how to do it some more.

[The Slab Bacon]

Precision tools? ? ? ? OY Vey, you dont have a drill and some small bits 

First off find sonething to use for the pins. (brass pin stock would be fine) then find a sharp drill bit that will make a tight but not quite pressed fit hole for the pin stock. Put the cap into a small vacu vise (or other small vise) to compress the spring and recenter the plates. (like you allready did) Then gently drill a hole all of the way through the flat side of the "nut" and shaft. Push the pin through the hole with a small pair of needle nosed pliers. File off the excess pin stock and VOILLA, done! If it makes you feel better, you can put a small drop of epoxy or crazy glue on the pin / hole before squeezing the pin into place.

A combination of the pin fit and the spring pressure is all that is really needed to keep the pin in place. IIRC, I used something around .050" for the pins (it was something I had laying around) If you are not in a big hurry check around, outfits like McMaster-Carr actually stock real rolled pins that small and smaller, but just about anything will work.