Vintage stereo repair?

Electronics
#1

I have little to no experience fixing electronics, however I just inherited a 1966/67 Grundig ks760u cabinet stereo/record player that needs attention. The stereo is in immaculate physical condition, but the left speaker set cuts in and out And the radio tuning knobs do not work. The unit powers on without issue, the record player works, and all the lights turn on. Due to the sentimental value, and my affinity towards vinyl, I would like to return it to its former glory. Anyone in the community have experience with this type of electronic that is willing to walk me through the process? I am willing to compensate you for your time and knowledge.

Best,

Kevin

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#2

@Team_Vector

#3

This vintage equipment is most likely vacuum tube based. Bring the unit by and I can check the tubes for you. I have a vast collection of extra tubes in case we need to replace one.

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#4

Thanks Rich-- I think you are correct that it is a Vacuum tube based system.Details on the tubes and specs can be found here.

I was doing some digging on Reddit and the community there seems to think the amp is the issue. I would love to connect at Makerspace to walk through what could be wrong.

Due to holiday travel, I am looking to start this project early to mid-January. Is there a time that works well for you that I should follow up on this request?

Best,

Kevin

#5

The tuning issue is probably a broken nylon ‘string’ that is wound around some pulleys and attached to a spring. Don’t take it off without noting how it is routed so you can properly replace it.

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#6

Just let me know in January when you want to meet.

In the meantime, you may want to check out the Vintage Radio and Phonograph Society which is a local organization. Suggest you make contact with this group, request some schematics and other information on your unit. This group of folks can help you as you bring your unit back to full operation. If need a new dial cord to fix your tuning dial, they have the parts and sources to do this.

#7

Here are the schematics to your unit. Now that we have the schematics,your unit is practically ready to run again.

Grundig_KS760U.pdf (519.2 KB)

This unit used the HF45U chassis. Here is another set of schematics in the German language. The text article, also in German, could be some restoration instructions. Find someone that can translate the article and we are in business.

Grundig_HF45.pdf (865.4 KB)

See the above file for a pictorial diagram of how the tuning ‘string’ is wound around the pulleys.

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#8

Hi Rich,

I came across this thread as my grandparents’ 1983 Zenith console recently stopped working. I’ve been calling around the DFW area trying to find someone who can help fix it. Any help/advice would be much appreciated. Located in Frisco. Phone is 8 3 2 7 62 0558.

Thank you very much,
Sam

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#9

You might try calling Metzger Vintage Audio in Plano - they specialize in repairing and selling vintage audio gear: https://www.metzgervintageaudio.com/

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#10

I have moved from Dallas to the Knoxville, TN area. I am no longer a member of DMS but check in on-line occassionally.

Perhaps I can still help you. Please provide any identifying information on your 1983 Zenith console. I can search for a set of schematic diagrams that could help someone else at DMS to repair your unit.

Richard Meyer

6 Likes
#11

I have an ex-TI buddy who restores vintage radios such as yours. He’s also a VRPS member. I’ll see if he has time/interest to take on your project.