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Old 13th May 2022, 8:26 am   #6
Heatercathodeshort
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Join Date: Jun 2005
Location: Warnham, West Sussex. 10 miles south of DORKING.
Posts: 8,744
Default Re: Ferguson - Thorn 980

Quote:
Originally Posted by Richard_FM View Post
These must have been one of the last 405 line only sets available.
I imagine many would have been used as second sets up to the switch off with only BBC2 & Channel 4 unavailable.
During the week following the 405 switch off I had around six 980's brought it for service. They all landed up in my junk shed at the shop and were passed on to 405 enthusiasts over the years. One was given to the guy that designed all the Thorn tuners and to a large part the 980 itself.

I retained a scruffy one and it still gets use as my 'workshop' TV!

These models were released in 1966 and were the last 405 line models produced. They were a good buy at 39 and a half Gns. Common fault was the line discriminator diode block and dry joints on the wire wound resistors. Cracked circuit boards were often caused by impact damage due to failure of the cabinet handle in a similar way to the KB/ITT Featherlight.

I have only had a few resistors change value but after all these years the plastic capacitors are all leaking particularly the frame stage and AGC decoupling and don't forget the little gray .01ufs. Other than the frame ones being tucked away under the tube, they are an absolute doddle to service.

Very high gain and would have been great in the fringe areas of 1950! John.
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