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Old 11th Aug 2017, 1:45 pm   #6
beery
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Join Date: Jun 2006
Location: Ware, Hertfordshire, UK.
Posts: 988
Default Re: And the next one! a GEC BT2147

Hi Matt,
I'm not sure I like them as much as John (HCS). The circuit design is fine, but the components are not so good...
I never tried re-stuffing the brown GEC capacitors, but it should be worth a try.

Points to look out for:-

The CRTs are usually bad, I fitted an MW22-18 in my set, taking the A1 supply from the boost capacitor.

The B36 is a weak point, but I managed to find a good one. The 12SN7 that John suggests is much better.

The U31 is also a weak point. I've had such a bad run with these that I won't use one now. Every time they develop a heater-cathode short the boost capacitor fries. I used a PY33 in my set.

The line output transformers can give trouble. Definitely worth drying out the overwind by passing a small current through it.

The set has those nasty sliding preset pots, but the ones in my set are just about ok.

The metal rectifier often goes leaky.

However the RF unit does not give any trouble.
Once restored these are good sets.

Hi Freya,
I might try that on my own set. I did wonder if the recent sagging of the mask on my set was due to me using turps based cabinet cleaner in the same room.

Cheers
Andy
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