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Old 25th May 2020, 7:58 pm   #23
Herald1360
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Join Date: Feb 2007
Location: Leominster, Herefordshire, UK.
Posts: 16,528
Default Re: Vidor CN429 Help wanted

The set looks to be quite heavily cost engineered with only one oscillator coil and a sketchy set of trimmer and padder capacitors giving little leeway for alignment. It's likely that unless the IF is set precisely to 470 kc/s, the rest of the alignment will be all over the place since it relies on one fixed padding capacitor (C6) for oscillator tracking on both LW and MW and there are no tracking (padding) trimmer capacitors in the aerial circuits at all.


This may explain the "way out" location of Radio 4 on long wave. It would seem likely that at best, the LW tuning would be a compromise, with only "Droitwich" lined up with any accuracy!


Good fun if the phantom twiddler has had a go at the IFTs and you haven't an accurate sig gen for IF alignment!
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