Re: Marconiphone 855 Silent on 49m
Hi Simon, normally I use a 25ft longwire in the garden but I also have a homebrew active loop in the loft. I know what you mean as the reception of actual signals, even background noise level, seems very variable on 49m. However, I know that the oscillator was stopping as I used the sig genny to test it. Also swapping the X63 for a 6K8G immediately brought up both noise and actual signals. I have a feeling that G6Tanuki is close to the source of this fault so I will play around disconnecting one or more of the 4uF (now 4.7uF) decoupling capacitors. I reckon the designers might have experienced difficulties "taming" this set on shortwave because the oscillator supply is taken directly from the rectifier cathode and then smoothed with 2 dropper resistors and 2 separate 4uF decoupling capacitors. The remainder of the HT supplies come from the remote end of the field coil. Cheers, Jerry
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