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Old 16th Jul 2017, 8:36 am   #24
ms660
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Join Date: Apr 2011
Location: Cornwall, UK.
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Default Re: First Radio Build - 12V HT system

Re: Post#22, a 500pF variable capacitor will tune the MW band with a suitable coil, but not with the 5uH coil that's shown in the schematic, to get a graphical understanding of what's going on have a look at the nomograph in the picture below, draw a line between an inductance value and a capacitance value then read off the frequency scale the resonant frequency in kHz of that LC combination. In that pic micromicrofarads is the same as picofarads (pF)

Lawrence.
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