I'll "third" that! What I've heard is that electrolytics fail more rapidly when they don't regularly see voltage. Hence a NOS part is likely as bad if not worse than what you started with. Similarly it's a good idea to bring up them old radios every few months to condition the caps. We all want to keep our older radios as original as possible but NOS caps don't seem to pay. AES has been offering new "cans" but in limited configurations and they are expensive. They also have a number of new commercial caps that are "close enough" and fit right in the old space (particularly fond of the J&J 100/100uf @ 500v). Many supplies use a 125uf and a 100uf will do (leaving you a spare!) or you can parallel them for 200uf which I've done. Only drawback I believe is initial surge that hasn't been a problem so far.
I've had some great results on a few radios rebuilding the cans. It works really well on paper covered ones as in Drake supplies and Heathkits. Used a hobby razor saw to separate the paper cover, then cut around the base of the cap leaving a small ridge. Drill holes through the base to solder the leads of the caps (the top of the lugs is aluminum and not solderable) and run a large common ground wire up for the other end (allows you to vertically stack axial caps in a limited space. Afterward the paper cover just slips on and it looks completely original. I think it's even less effort than trying to crowd a number of discrete caps under a chassis without any mounting points. Kinda fun in a disturbing boatanchorish kinda way! 73, - Mark K9MRK > I agree about the use of "surplus" or NOS electrolytics. Don't use them no > matter how tempting. Just because they are unused doesn't mean they are good. > They may be the same age, or older, than the component you are replacing. > Replace them with the new, smaller components. Leave the old multi-section can > in place on top of the chassis and put the new caps under the chassis, if > possible. An alternative is to replace the "guts" of the can with new caps. I > haven't done this (yet) but I have seen some very good results in units worked > on by others. > > George, I'm glad to hear your TR-4 survived due to your quick reflexes! > > Ken, WA2LBI > [EMAIL PROTECTED] ---------------------------------------------------------------------- Submissions: [EMAIL PROTECTED] Subscribe: [EMAIL PROTECTED] - subscribe drakelist in body Unsubscribe: [EMAIL PROTECTED] - unsubscribe drakelist in body Hopelessly Lost: [EMAIL PROTECTED] - help in body of message Brought to you courtesy of TLCHost.net http://www.tlchost.net/ ----------------------------------------------------------------------
