Do Electronic Components Age if Unused for Long Periods?

michaelnorth

New Member
Hi,

I retrieved a few items from long-term storage. A Technics SA-700 stereo receiver from 1978, a Tascam 112 Mark II tape deck from the 80's, an Otari MX 5050 BQII 1/4 inch Tape Recorder, etc.

I know for a fact that the Technics unit has not been turned on in 25 years, and was only lightly used before that. Similar story with the other items.

So I'm wondering: Do typical components like capacitors, resistors, and transformers actually age if not used?

Do these older home stereo items need re-building? Or are they likely to be just fine in terms of sound quality per the original specs?
 
Tape deck belts turn gummy..Capacitors dry out. Transformer will last forever as long as they are in and dry enviornment.
 
@avionic Storage conditions were OK, no excessive moisture. Sounds like the capacitors are the main issue. So we're talking about pulling them and replace with new?
 
@avionic Storage conditions were OK, no excessive moisture. Sounds like the capacitors are the main issue. So we're talking about pulling them and replace with new?
Perhaps if they are in rough shape. Pop the hood on the 700 and have a visual looksee.I don't know if Technics used sony bond glue or not. The dried glue promotes corrosion of any metallic surface it contacts.
 
Every alloy of metal made by man begins to break down right after it is made. Un-natural also break down in short order. Long term storage will also see things age, in fact there was a pair of "never opened" AR speakers that had foam rot on the woofers.......
 
Thanks everyone. I'm going to open up the case of the Technics receiver to see how it looks. I'm still not clear on how to figure out if capacitors are bad, other than just looking for obvious corrosion, disintegration, etc.
 
Thanks everyone. I'm going to open up the case of the Technics receiver to see how it looks. I'm still not clear on how to figure out if capacitors are bad, other than just looking for obvious corrosion, disintegration, etc.
I think that it's only electrolytic caps that you have to worry about. You should note that as far as I'm aware no electrolytic capacitor manufacturer guarantees storage lifetimes beyond 15 years due to degradation of the stopper/bung that retains the electrolyte solution. Electrolytics fail, even when not biased, due to evaporation of the electrolyte and the degradation of the oxide layer on the anode. The lifetime halves for every +10c change in temperature above normal room temperature. So, if the unit has been in storage for 25 years, it's probably best to swap out the caps as the only sign that might present itself is that they just don't work as caps any more- they could have low capacitance and very high ESR. You won't see the bulging etc. if the electrolyte has simply evaporated away and can't boil, and the failure of the cap might be very subtle and not at all visible.
Hmmm. Perhaps I should take my own advice and change the caps on my Otari MX50II tape deck from 1991.
 
Last edited:
If the unit has been in storage for 25+ years I would not turn it on immediately. The Electrolytic Caps will need to reform. I have seen main filter caps blow from this exact thing.

You can use a Variac to power it up slowly, and I mean 20 minutes or more each setting of 25% input voltage, 50% input voltage, 75%, 90%, 100%. There are procedures on how to do this on AK.

Even if it powers up and operates after this, I would still replace the electrolytic caps to expect to get full performance.
 
In my experience, just about everything short of a tank of gas benefits from regular use.


As a vintage motorcycle and classic car enthusiasts / shade tree mechanic....

Ethanol gas sitting even a few months will gum up carbs and absorb moisture enough to rust tanks :)
 
As a vintage motorcycle and classic car enthusiasts / shade tree mechanic....

Ethanol gas sitting even a few months will gum up carbs and absorb moisture enough to rust tanks :)
I use Sta-bil ... and we still have ethanol-free gas around here. But regardless, it was just a little joke.
 
Smartass alert: Everything ages.

"Look! This is a picture of me when I was younger!"

"Every picture of you is a picture of you when you were younger. That would be one helluva camera!"

- Mitch Hedberg
 
Smartass alert: Everything ages.

"Look! This is a picture of me when I was younger!"

"Every picture of you is a picture of you when you were younger. That would be one helluva camera!"

- Mitch Hedberg
Ahhhh.. But somethings age more gracefully than others.
 
Thanks everyone. I'm going to open up the case of the Technics receiver to see how it looks. I'm still not clear on how to figure out if capacitors are bad, other than just looking for obvious corrosion, disintegration, etc.
Change them as a matter of fact that they are compromised by non-use. Otherwise, you'll need a cap. meter, ESR meter and leakage tester.
 
Ahhhh.. But somethings age more gracefully than others.

Poor Mitch is done aging. One of the funniest guys ever, but he had that monkey on his back. "I used to do drugs. I still do, but I used to, too."
 
Back
Top Bottom