Powering on OLD stereo

[Marauder2003]

Joined the forum today.

I have a Pioneer SX-1050 receiver from 1976. It has not been powered up for at least 15 years. I have heard of a few ways to start it up.

1. Turn it on and hope for the best.
2. Plug it into a variac and crank up the voltage slowly
3. Plug into a current limiting device like a Christy tester.
http://antiqueradio.org/ChristyTester.htm

I don't think number 1 is wise. I also hear solid state devices don't like variacs.

Not having a Christy what else are my options? The caps are 39 years old. I am a little concerned.

[Compgeke]

Re: Powering on OLD stereo

I would build a dim bulb tester and try it out on that.

With solid state I've yet to have anything burn up that wasn't previously dead with just plugging it in without a variac, however a dim bulb tester is useful for testing for shorts in the power cord and similar areas.

If it turns on (no pops or sizzles or anything like that) then grab a multimeter and check for DC on the outputs and the dc offset on the speaker terminals. This here will help check if you're speakers are safe from DC voltage which isn't a good sign to have, a couple millivolts max.

If you don't have a multimeter on hand just grab something to use as an input (a phone with a 3.5mm to RCA adapter works fine) and stick a sacrificial speaker on, hope for the best. If you get sound at all, woot!

Now, odds are your controls are going to be staticy, as in you turn volume\balance\etc and a channel cuts in and out, has static, quiets down, etc. This here's dirty pots and switches. For this you'll need contact cleaner, alcohol based works best and non-lubricating is even better. I myself use Faderlube and Deoxit. Use your favorite contact cleaner on the switches. Spray some in and toggle\spin them a few times, maybe for 30 seconds or so. With the pots use the faderlube and do the same. The thing about deoxit is it's known that it can eat the carbon traces in the pots, rendering it useless. I've personally used D5 in pots before with no issues, but anything with deoxit in pots is on you.

After all that you'll probably have some lamps to replace if you want for prettyness but it'll be good to go. Just note that sometimes they liked to wire lamps in series rather than parallel so if one burns out all the front go out; Kenwood was especially good at it.

I've personally used this method on a bunch of old receivers, such as Harman Kardon 330B, Kenwood KR-6160, KR-4070, KA-5700, Sansui G5000, etc and never had an issue.

Now, if something goes pop, it doesn't do anything, etc post back with results from that. It's hard to diagnose everything right off the bat that may be wrong as so much could go wrong.