One man asked me to repair his not working SONY ICF-SW7600 which he bought in 2008 for parts.
I never have deal with SONY before so I immediately agreed.
It is legendary and well known model http://stephan.win31.de/sony76-2.htm
I also learned a lot from this thread viewtopic.php?f=4&t=303062&hilit=7600
So today I got it in my curved hands )
A little bit dirty enclosure but not bad at all

It even turned on, but did not respond to the buttons.
Inside I was greeted by a stuffed cockroach

Traces of electrolyte from under the capacitors looked terrible, but the pads are surprisingly in good condition.


So I ordered and am waiting for new capacitors.

I have dozens of SONY radios from all decades and I have never seen anything like this one.

My icf-7600D from 1985 is absolutely perfect in every respect, and a bit of a sleeper radio as it will receive strong FM signals with the antenna down and folded in place!
… and I'm in the Boonies ▼
https://www.collinsdictionary.com/dicti ... of-nowhere

More photo

It is not difficult to disassemble the receiver, so I changed more than two dozen capacitors. Quite a laborious job because you have to do the following operations:
1. twist the old cap.
2. cut off his legs.
3. rinse the place with alcohol.
4. dilute old solder with new solder.
5. use braid to remove all solder.
6. repeat step 3.
7. solder a new cap.
8. repeat step 3.
The mount is dense, so you have to act as carefully as possible so as not to damage neighboring parts.


I added 100nF cap above new C127 in the DC/DC converter

The first power-up was successful, but I found that on AM the frequency did not match at 10kHz and the synthesizer needed to be tuned.



On FM I could not receive a single station at all and decided that it also needed to be tuned.
Then I moved on to FM tuning and again, the values ​​were far from the desired ones. But it's easy to fix.

And then I found that I could not adjust the FM input circuits and I had to set the oscillator signal level too high to hear anything. Checking the voltage on the transistor Q13 showed its absence.

I spent more than two hours to check all the elements and traces and find the reason for the lack of reception on the FM.
Under one of the capacitors glued to the board, corrosion apparently destroyed one of the tracks. I had a hard time finding the exact place where it happened. Next came radio microsurgery.



After that, I was able to adjust the FM and the radio perfectly receives both AM and FM.
After cleaning and assembling, I want to keep it for myself)

video https://youtu.be/BPOSh1Z1fMM