Re: Variation of secondary Q

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

Original poster: "Jim Lux by way of Terry Fritz <twftesla-at-qwest-dot-net>" <jimlux-at-earthlink-dot-net>

> Digital scopes have crystal controlled time bases.  200PPM Max error.
Over what temperature range?? (Since you've mentioned freezing cold, etc..)
I've found that most scope time bases, compared to something decent, to put
it bluntly, are horrid..... If you are interested in measuring things
accurately, you might contemplate a reference input of some sort..

Hmmmm.. Now, Terry, there is a huge transmitter of signals at convenient
frequencies accurate to 1 part in 1E13 fairly close to you....
One transmission is at 60 kHz, which might be useful....  You're close
enough to get the ground wave, so ionospheric uncertainty shouldn't bite
you...




>
> >Use a search coil eg
> >ferrite rod for the field pickup and tune it to some convenient
> >24hr long wave transmission so that a little of it appears in the
> >scope trace along with the TC signal.

Pick up the 60 kHz and mix it in... An FFT will make a dandy filter to
separate things out...