Re: resonant freq.

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: "Sean Taylor by way of Terry Fritz <twftesla-at-qwest-dot-net>" <taylorss-at-rose-hulman.edu>

> Nothing wrong for frequency measurement, although the 1 k resistor
> will result in a fairly low Q circuit and the frequency for exact
> minimum may be hard to determine accurately.  A simple way around 
> this is to connect the direct signal from the signal generator to 
> the horizontal axis of the scope and the voltage at the bottom of 
> the secondary to the vertical axis.  Provided the frequency
> response of the scope is good enough the resonant frequency is that 
> at which the resultant lissajou pattern is a straight line rather 
> than an ellipse.  This can be a very sensitive test and is one I 
> use in adjusting the resonant frequency of audio filter circuit.

So the resistor is still there you mean? What's basically going on is
you're checking if the two signals are in phase, quite a bit of signal
gain will most likely be needed for the probe at the base of the
secondary, or a smaller resistor should be used to make a slightly
higher voltage at the base.  Am I seeing this correctly? 

Thanks!
Sean Taylor