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Old 1st Dec 2019, 11:54 am   #38
allan
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Join Date: Oct 2005
Location: South coast near Ringwood/Christchurch, Dorset, UK.
Posts: 230
Default Re: RCA AR88D Comms Receiver.

I'm currently overhauling my Moreton Cheyney receiver. It uses a 6K8 mixer and a set of standard Wearite coils covering 5 wavebands.
The local oscillator works on only part of the medium waveband.
The HF end 800KHz to 1600KHz (osc=1265KHz to 2065KHz) works with the higher RF voltage having a greater value and completely fizzling out by 1265KHz. None of the other 4 wavebands have any local oscillator output.
The 6K8 voltages all look OK. As the receiver was missing its mixer it could have been an X63/6A8 or similar but trying that shows it performs exactly like the 6K8.
None of the coils uses a dust core. Changing the HT voltage from 150 to 300 hardly makes any difference. Clearly another case of nonoscillatoryitis.
Allan G3PIY
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