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

Boy, what an adventure! Great repair job on a classic portable. Thanks for all of the images and notes. Very informative!

Mike, N0TLD

Thank you Mike!
I hope this will be useful to someone and perhaps inspire also to bring some old radio back to life.

Today I started repairing another Sony ICF-SW7600.

The owner complained about poor performance and lack of FM. When I opened it, I saw complete horror.

After I threw out all the wrong parts and washed the board, I saw the consequences of the previous "repair".

Following with bated breath. Excellent photos.

Cheers Geoffqf

Very useful info. I have the exact same receiver and have done the exact same repairs with the same damage to the board. Mine works fine now except AM is offset now and I need to use the fine tuning instead so I must have missed a defect. I don't plan to disassemble it again.

Have you did alignment according to the service manual?

No I didnt. Its not a big deal but maybe Ill open it up someday and run the alignment. When I did mine I didnt have all the info you provided which is very useful.

Since I only have electricity and internet for a few hours a day, mostly at night, doing repairs is much more difficult now. However, we continue.
First you need to restore the torn off C2 and C89 capacitors pads and PCB through hole rivet. It is B+ line

C127 in the DC/DC converter mod is done.



All capacitors have been replaced.


The first power up is successful.


2nd local adjustment


3 kHz step adjustment


5 kHz step adjustment


FM VCO voltage adjustment

Also, someone over-twisted the Fine Tuning RV1 pot and it was jammed. I had to disassemble it, clean it and reassemble it correctly.



The rest of the adjustment was also made and the plastic of the screen was polished.

video https://youtu.be/9gQ3AwwvBBU

I got another one 7600 in excellent condition for restoration. It is really new and has probably never been turned on. Complete with box, but hardly receives anything. The electrolytic capacitors need to be replaced and the adjustment must be checked.

Spectacular!

And thanks for posting the pictures, they make great reference information!!!!

Geoff