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Old 15th May 2021, 2:55 pm   #1
monaro0162
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Join Date: Sep 2016
Location: Stansted, Essex, UK.
Posts: 185
Default Bringing a Sony C7 Betamax back to life

Hello,

I recently acquired a matching pair of Sony C7 UB Betamax video recorders, they are from around 1980 I believe. I've had success in getting a Sony VO2630 umatic and a number of Panasonic VHS machines fully working in the past, and thought that it was about time I added Betamax to the collection!

Both C7's were completely dead on arrival. I found a couple of open circuit capacitors in the power supply, so I did a complete recap and the power supply is now working.

Next was the dead clock/timer and display. It had multiple problems of corroded ribbon cable connections and pcb tracks, stuck buttons and gummed up switches. Repairing the ribbon cable and pcb tracks was a horrible job, but it's now working and able to power up the main unit. The clock runs but time display is not quite right, I may have missed one of the connections, but I can come back to that later.

On loading a cassette its pulls the tape out and wraps it around the head, but on eject there is no movement of the reels to pull the tape back into the cassette, so it gets tangled up. Nor am I seeing any spinning of the video drum, but mechanically it feels perfectly free. Looking at the belts underneath they all feel very loose and will obviously need replacement.

The rest of the electronics seem to be working it is passing a video source signal through, the picture is fine, and even the UHF tuner works. Mechanically it all seems fine inside, grease still present on what I can see of the mechanism.

I'm optimistic that I can get this C7 running again.... but how on earth do you change the belts..it doesn't look easy.

Any advice (other than chuck it in the bin!) appreciated
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