Posts: 18
Threads: 5
Joined: Jun 2012
City: Texas
Holy cow. I've just discovered a whole batch of these electrolytics in a newer Maggy (solid state) that are ALL bad!. Strangely, the thing still kind of worked. So far I've replaced about 18 of various values. If you ever run across a nice early transistor Maggy that has NO output, the first thing to look for is the output caps. Usually a 200-400 mfd value which are directly in series with the output. They're usually shot and replacing these will at least get an output. The last one I got also had a bad main filter cap which was also kind of strange. It had Common Positive. Guess back in those days for a time the common was actually positive vs. negative.
Maybe I'm so new to this stuff that this is old, stale, news, but once you get these newer old Maggies going they sound pretty good and have super bass with the 15" woofers.
Posts: 16,213
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Joined: Oct 2011
City: Jackson
State, Province, Country: NJ
Don't foget that earlly in the game Japs were what Chinese are today, that is manufacturers of crappy cheap stuff. They came a long way, then Coreans, now Chinese.
But, well, this notwithstanding, no electrolytics live this long, even the good ones.
Posts: 18
Threads: 5
Joined: Jun 2012
City: Texas
For sure. And the Chinese stuff we're putting in now will last how long? I'll be under the ground, hopefully, and the next generation will have to deal with this.
It is interesting however, that some of the old FP can caps still function. I know, a Time Bomb waiting to do it's thing. I'm thinking that the environment these things are kept in has a direct relationship to how soon they fail. Down here in TX if people keep these old relics outside or in a hot shed that will probably shorten the life of anything, but especially the lytics. I've replaced about 30 of these Nichicons on this one Maggy. This solid state stuff seems to use many more small value electros than the great old tube stuff used. But, can't say that the price difference is much from the old paper caps which I almost always replace. Many of those, however, according to my tester seem to be okay or within tolerance even after 50 or 60 years.
Posts: 16,213
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Joined: Oct 2011
City: Jackson
State, Province, Country: NJ
Lyrics and anything with electrolyte in it do not like heat. Lead acid batteries are notorious for shortened shelf life when stored in hot warehouses.
Yes in my Zenith I had a triple cap, of which two caps were functional and one was totally dry (I wonder how that happens in one can). I had to replace all three.
As for longevity of today's caps, the film and ceramics are, I think, have no limits, and lyrics I choose with large ripple and hi temp, so they should be OK for a long time.
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Joined: Oct 2008
City: Merrick, Long Island, NY
Conservative designs an environments tend to favor componants, as does occasional use. Agree that for the most part, newer parts are either defective or will outlast most of us. I test before installing.
Posts: 16,213
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Joined: Oct 2011
City: Jackson
State, Province, Country: NJ
When bought from major mfrs, who are many today, I hadn't seen many problems with todays parts. Nichichojn, Rubycon, Chemion, Panasonic, Tayo Yuden, TDK, All work fine.
I design conservatively.
My switcher for optical modem battery backup, that works in India and so had to be tested up to 270V AC, and at 50C ambient at full rated power, passed the tests just fine, and ha been manufactured in qtys of few hunderds of thousands. But I did choose high ripple low ESR switching grades for input and output etc., and with good room to expand.
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