Old Radio Caps: are these any good?

[Kinetic99]

Hello and thank you for your time,

I was hoping to get some help from this great forum to identify these caps (see images). They are from an old 1950's radio in which I want to restore.
From what I gather, its best to replace some old-style caps and also to leave some alone if they are mica or ceramic style for example.

My question is, do you think the caps in these images are good to keep or should they be replaced?

Types observed:

1) Big and small wine-red caps with a worn out plastic sheath and black text
2) Metallic Blue caps
3) Light Green-Blue plastic sausage caps with black text
4) Wine-Red mini Bumble-Bee cap with 4 colored stripes (located beside the light green-blue sausage cap)
5) Various strange caps: violet tubes, violet disc,

Anyways, sorry for the bad description but I needed to show them to you.

I assume the small bumble-bee versions with colored stripes are resistors?

thanks for your help.

[bluto]

Re: Old Radio Caps: are these any good?

I have done a 1930's tube radio and those had wax capacitors that all needed to be replaced. Yours are probably OK. I would definitely replace the filter caps (electrolytic) that are probably dried out. After doing this, use a variac to slowly bring up the power for turning it on the first time. If you don't have a variac, use a 100 watt light bulb wired in series to the power cord. If it lights up bright, you have something shorted. If it flickers dimly then it is probably OK. This is called a dim bulb test. If fact budm's dim bulb tester was just mentioned in another thread.

http://s807.photobucket.com/user/bud...01682.jpg.html

[Kinetic99]

Re: Old Radio Caps: are these any good?

I have done a 1930's tube radio and those had wax capacitors that all needed to be replaced. Yours are probably OK. I would definitely replace the filter caps (electrolytic) that are probably dried out. After doing this, use a variac to slowly bring up the power for turning it on the first time. If you don't have a variac, use a 100 watt light bulb wired in series to the power cord. If it lights up bright, you have something shorted. If it flickers dimly then it is probably OK. This is called a dim bulb test. If fact budm's dim bulb tester was just mentioned in another thread.

http://s807.photobucket.com/user/bud...01682.jpg.html

thanks for the info.
Which ones are the electrolytic caps?

[kc8adu]

Re: Old Radio Caps: are these any good?

the ones you posted are reasonably reliable.
its the wax paper,black beauty/bumblebee,and electrolytic types that get replaced before you do anything else.
lytics have + - markings.

[PeteS in CA]

Re: Old Radio Caps: are these any good?

Those are probably mostly impregnated paper dielectric, which don't have drying out as a wear-out mechanism. There may be some plastic dielectric types as well, though I'm not sure whether plastic dielectrics were in use in the 1950s (I think I've seen ads for Sprague Orange Drop © capacitors in 1950s TV repair magazines). Those hollow cylindrical ones are probably ceramic. The solid cylindrical parts with stripes that do not look like carbon composition resistors may be inductors.