capacitor trouble finding replacement

[nj pheonix]

I haven't looked at the layout of the receiver but typically, there would be other electrolytic capacitors that also need changing. Cleaning the pots is mote or less standard as they can send all sorts of trouble down the line.

I would say there's a difference between being a repair man and being a hifi tinkerer. The repair man wants to find the problem quickly, replace the broken part and move on to the next unit. A hifi tinkerer is doing it for fun, to learn and to have the best possible unit at the end of it.

As a hifi tinkerer I think it's pointless to start detailed diagnostics while you still have old electrolytics or inferior parts in the unit. You know it will measure wrong. If you start by cleaning and changing all the usual suspects, it'll be much easier to diagnose any actual problems after that.

Maybe I'm understanding you wrong.
While anytime a get a new piece (to me ) cleaning contacts is generally an early operation.
If i get something I know is broken. Unless caps is a likely cause, id be trouble shooting first.
If you don't solve the problem with the new parts, you run the risk of having podged something up while replacing parts (that creates other problems).
I think it more prudent to get past initial issues.
Once there , I have no issue with replacing old elytics.
Beginners likely better served by going a board at a time, perhaps a channel at a time. Then rechecking to make sure service didn't screw anything up, and you have an in tact channel with polarity and values and all.
Also it wasn't mentioned but pictures (before pictures)(the more the better) are your friend . Wide, close, every angle. It helps a great deal with reassembly.

 

[nj pheonix]

Okay,
We'll agree to disagree on the approach.
We agree vintage elytics need to be replaced for long term reliability. Some of what i mentioned was aimed at someone learning to do their own (though applies to most).
Maybe you're very experienced, fast, or tend to work on gear that's easily accessible.
I find ,more often than not, by the time I open, clean, inspect, download the manual, observe all the current values, measure diameter and lead spacings , take pictures, put a together a parts list , place order and install parts , an evening is a pipe dream.
In some cases just changing parts once on hand could only be several hours but it doesn't mean I didn't spend the time.

 

[Skywatcher]

I started doing repairs and restorations in small steps, as that is often recommemded. For me it had several drawbacks, not least because the health of one circuit may affect the performance of other circuits in complex interdependencies.

I also found a lot of oxidation and bad solder joints. The latter were more difficult to identify if you fixed one board but the bad solder was on a different board.

So, my new method is to break down the amp and do all the given work, i.e. clean, check solder joints, recap, measure resistors, check for shorts etc. That work can be done in an evening.

Then you can reassemble the amp and do some tests and measurements. As the first step eliminated common and simple causes, you'll know if you have a more serious problem now. If not, you can do a listening test.

Naturally, I'll start by reading up on the amplifier, studying the schematics, googling for common faults and ordering needed parts. That can take a few evenings. But the actual work can be quite quick unless there is a serious fault.

Try that "one evening trick" with a Sansui G-9000/9700DB...

 

[spark1]

I started doing repairs and restorations in small steps, as that is often recommemded. For me it had several drawbacks, not least because the health of one circuit may affect the performance of other circuits in complex interdependencies.

I also found a lot of oxidation and bad solder joints. The latter were more difficult to identify if you fixed one board but the bad solder was on a different board.

So, my new method is to break down the amp and do all the given work, i.e. clean, check solder joints, recap, measure resistors, check for shorts etc. That work can be done in an evening.

Then you can reassemble the amp and do some tests and measurements. As the first step eliminated common and simple causes, you'll know if you have a more serious problem now. If not, you can do a listening test.

Naturally, I'll start by reading up on the amplifier, studying the schematics, googling for common faults and ordering needed parts. That can take a few evenings. But the actual work can be quite quick unless there is a serious fault.

To be clear, you are claiming that you can fully recap a 70s era integrated amp or receiver in one evening? And also check all resistors, check all solder joints, and clean all boards? How long is an evening where you come from?

 

[Skywatcher]

No problem. Send me one and I will

You'll spend some time just assembling all the VD1212 and MV12 replacements alone, not withstanding installing all of them in the various boards and removing all the glue...