Quote:
Originally Posted by DonaldStott
if only I knew how to about calculating the approx min and max parallel capacitance values? I know that for capacitors in parallel you simply add the individual capacitances
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Hi Donald, good skills.
If this is the main tuning capacitor, work with 0 min to 500 pF max for a generic AM capacitor. That's both sets ganged together.
I don't have set specifics but that's your average twin-gang air-vaned capacitor. I think 365pF or so for the large section IIRC.
Your frame aerial is fine. -- I've just popped in some values for illustration.
Your 0.21mH tunes the lower frequency end of the medium wave band (550 KHz -- which is also approx the same no of metres) with 400pF. It tunes the higher frequency end (200m or 1.5MHz) with about 50pF . As I say I'm not familiar with the exact design but this is generic info. Most sets have padder capacitors to get these lower values of Pifs bang on - does yours?