28-10-2013, 06:22 PM
Glad someone thinks it might be useful. 
A bit of history. It all began during my attempts to build an experimental Q-multiplier: the centre freq. was 100 kHz. I estimated that a freq. swing of ±3 kHz would be sufficient and I had a 5 - 100 pF variable capacitor available. A bit of elementary analysis established that that 'known data' would be sufficient to determine the value of the fixed cap. in parallel with the variable cap. and coil - and the inductance value of that coil, too. However, not only could I then see that doing the calculations the traditional way would be labourious and prone to error, but that there was a reasonable chance that one day I'd be repeating the arithmetic in some other design task. My first reaction (as usual) was to look around the 'Net (as you do: there's nothing I'm ever going to create that someone else hasn't already done
), but, surprisingly, couldn't find the appropriate tool. Anyway, I like EXCEL for things like this - you can customize the 'application' to your own tastes and needs. And unlike things on the 'Net', I won't find that one day it's simply vanished. 
Al. / Oct. 28, '13.
A bit of history. It all began during my attempts to build an experimental Q-multiplier: the centre freq. was 100 kHz. I estimated that a freq. swing of ±3 kHz would be sufficient and I had a 5 - 100 pF variable capacitor available. A bit of elementary analysis established that that 'known data' would be sufficient to determine the value of the fixed cap. in parallel with the variable cap. and coil - and the inductance value of that coil, too. However, not only could I then see that doing the calculations the traditional way would be labourious and prone to error, but that there was a reasonable chance that one day I'd be repeating the arithmetic in some other design task. My first reaction (as usual) was to look around the 'Net (as you do: there's nothing I'm ever going to create that someone else hasn't already done
), but, surprisingly, couldn't find the appropriate tool. Anyway, I like EXCEL for things like this - you can customize the 'application' to your own tastes and needs. And unlike things on the 'Net', I won't find that one day it's simply vanished. Al. / Oct. 28, '13.
