Re: Harmonics


Tesla List wrote:

> Original Poster: Russell Babylon <babylon-at-ccpl.carr.lib.md.us>
> Being new at tesla coils I have a basic question.  Should the
> frequencies at which your primary and secondary coils operate be
> harmonics?  I assume that this is what is happening when people speak of
> adjusting the primary coil with some sort of adjustable tap.  The power
> transfer should be greatest when the secondary is operating at a
> harmonic of the primary coil frequency.

There are always harmonic frequency's, but this is not why we tap the
primary coil. The tap is used to tune both LC's to the *same* frequency.
This frequency is the *resonant* frequency. In most cases, the secondary
coils construction makes it difficult to change the inductance or
capacitance. On the primary side, the cap (usually) is a fixed capacitance.
The primary coil however can be tapped to change the inductance. So, we wind
a secondary and throw on a top terminal. This secondary configuration has a
natural LC resonant frequency. We then design and build our primary LC
circuit and use the primary coil to change the inductance until Primary LC
equals the Secondary LC's resonant frequency.

Hope this helps,