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Old 18th Feb 2015, 12:36 am   #15
Phil G4SPZ
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Join Date: Apr 2005
Location: Bewdley, Worcestershire, UK.
Posts: 4,736
Default Re: Trio 9R-59DS communications receiver (1970)

Quote:
Originally Posted by Radio Wrangler View Post
...What takes your fancy? An RA17...
Ah yes, the RA17. I was given one once, complete with the metal rack case. It weighed a ton and it worked very well but it virtually filled my shed. When it broke down I literally hadn't enough room to dismantle it to find the fault (nor probably the knowledge) so I swapped it for a far more useful DFM.

I agree with you David about keeping my example as original as possible.

I've since been playing around measuring drift and mains voltage to see if there is any correlation. The answer is yes - I can use my variac almost as a fine-tuning control - but I think it's more related to temperature than anything else. At switch-on, the drift is in one direction (LF) but after about 20 minutes, during which time it drifted down by 2kHz, the frequency settles down a lot. Until, that is, there's a slight change in room temperature or mains voltage, which sets it off again.

One question - is the main VFO valve V3 supposed to have a metal shield over it? The valve base has three springy metal fingers that grip the base of the valve, but my set has no shield. The picture in the service manual isn't very clear, but may show something covering the valve. If anyone can tell me, I'd be most grateful.
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Last edited by Phil G4SPZ; 18th Feb 2015 at 12:36 am. Reason: Typo
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