[Project80Pete]

So I’m just starting to research how to go about restoring my old 50-1724 and I have an uncle that recommended powering it up and leaving it for about 24 hours which he said will referbish the caps...has anyone ever tried this and what was your result?

[morzh]

What he refers to is called "reforming". Yes it is a valid procedure but only for those caps that did not go all dry or crystallized inside. Doing it to an old radio is not a great idea. And if done to a radio with caps from, say, 70-s that still could be reformed, the radio should never be left unattended, so much for 24hrs.

And this only works for electrolytics. Not paper caps.

So, in short - don't do that, change the caps.

[Project80Pete]

Perfect thanks

[Mountaineer]

Frankly my rule is never to leave any old tube radio on for long periods of time unattended.  Even if it's been recently restored.  That way if something blows up or starts to smoke, I'm there to unplug it and put out the fire! Have fun with the repairs and best of luck!

Jason

[Project80Pete]

Thanks Jason, will do

[morzh]

Frankly my rule is never to leave any old tube radio on for long periods of time unattended.  Even if it's been recently restored.  That way if something blows up or starts to smoke, I'm there to unplug it and put out the fire! Have fun with the repairs and best of luck!

Jason

I even go further than that: all my radios are powered through power strips, and I only turn a strip on when I play a radio that is plugged in it, and after I turn of the radio, I also turn off the strip.
Better safe than sorry about losing both the collection and the house.

[Arran]

Reforming an electrolytic filter capacitor, inside a sealed aluminum can, may or may not work depending on how old they are. I have encountered some "dry" electrolytics, in the twist lock style cans, in sets from the early 40s that were still functional, but I would not trust them, the 1960s maybe. If they are the cardboard cased ones, that look like a toilet roll, with a wax plug in the end, no, those are garbage, they were only meant to last about 5 years from new, the only thing they are good for is a tube for restuffing purposes.
Regards
Arran

[morzh]

I successfully reformed a few caps from end of 40-s or 50-s, axial types in my RF generators and military grade aluminum, painted grey, in two audio generators, BTW these did exceptionally well.
But old radio caps are sometimes simply dry and then no amount of reforming helps as there is no electrolyte, and then lots of crystallization inside also doesn't help.