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Old 24th Aug 2013, 10:15 pm   #26
Top Cap
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Join Date: Mar 2006
Location: Watford, Hertfordshire, UK.
Posts: 1,211
Default Re: "Universal" valve radio

Please Please check that the mains Neutral is going to chassis, the neon screwdriver seems to indicate otherwise .

Change those wax capacitors and also the Brown coloured capacitors - they look like Hunts Mould-seals which by now will be behaving like resistors rather than capacitors. What ever you do, do not touch the metal rectifier with the radio powered as this could kill you! Fit a solid state diode with a 100 Ohm wire wound resistor in series, there are posts on this Forum that cover this aspect. Completely isolate the metal rectifier from circuit - you could do what I did with a similar radio - I kept it in physical position but not wired, to retain some of its vintage charm .

It might be a good idea to draw the circuit diagram from what you have now, it is not too difficult for such a simple radio. You will then be able to study it, put it on this Forum even, the colossal amount of technical knowledge available here will be able to suggest improvements or highlight areas of poor circuit design to make the radio better.

I love these old sets as they are such a lovely challenge.

I will attach a circuit of my kit 'Premier' radio, the great thing about kit radios is that you can do whatever you like with the circuit. No need for originality as after all - it is a kit radio
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Whether the Top Cap is Grid or Anode - touching it will give you a buzz either way!
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