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Tesla coil tuner (grid-dip meter)
At 02:32 AM 2/6/99 -0700, you wrote:
>Original Poster: "jim lux" <jimlux-at-jpl.nasa.gov>
>
>>Original Poster: Scott Stephens <Scott2-at-mediaone-dot-net>
>>
>>I've found a grid dip meter is a very handy tool to have for checking
>>filters and other circuits. The grid dip meter (a simple transistor
>>oscillator with a sensitive current meter to measure RF absorption peaks)
>in
>>the ARRL Handbook also functions as a tuned RF field strength meter when
>>oscillator current is cut.
>
>
>There are a number of devices sold to the amateur radio market that might be
>useful. For instance: The MFJ259B measures Z (both R and X) as well as L or
>C over typical rf range. I don't know if it will go down to 100's of kHz.
>try http://www.mfjenterprises-dot-com
No, it only works 1MHz to 250 MHz, Copied this from the web page:
"Here are some of its many uses . . . determine resonant frequency of tuned
circuits and adjust antennas for optimum performance . . . determine
electrical quarter and half wave lengths of transmission lines . . . measure
the velocity factor of transmission lines . . . measure capacitance and
inductance . . . measure mutual inductance or coefficient of coupling of
coupled coils . . . measure the Q of a coil . . . use it as a signal
generator to align receivers and for supplying RF for antenna measurements .
. . use it as a field strength meter . . . use it as a crystal oscillator .
. . use it as a neutralization indicator for transmitters and linear
amplifiers without turning on your transmitter . . . find the frequency of
parasitic oscillations in tube and solid state transmitters and linear
amplifiers . . . you can even use it to locate metal and trace hidden wiring
or metal pipe."
Hopefully I can build one that goes all the way down to .1 Hz and gives a
precise, crystal-based frequency counted output, has a variable Q setting up
to 10,000 +/- 20% and can demodulate AM, WB & NB FM. That's what I'm aiming
for anyways.