500 kHz VFO ?

Andre Kesteloot andre.kesteloot at verizon.net
Tue Jan 3 10:37:02 CST 2006


Gang,

Just as an experiment, I decided to assemble the permeability tuned 
Vackar VFO kit offered by WA6OTP
    http://www.wa6otp.com/pto.htm

For about $21 (incl. postage), you receive all the parts. If enclosed in 
a metal box (not included), and kept at fairly constant temperature, the 
oscillator  --after an overnight warming up period--  drifts less than + 
and - 25 Hz at 7.500 MHz.  (as measured on my HP 5245L counter).
If it were to be re - dimensioned for 5 MHz (or 10 MHz), and followed by 
a divider by 10 (or 20), we should be able to expect a stability of 
about + and -  2.5 Hz at 500 KHz.
Because the output is only about 0.3 volt RMS, the only thing that would 
need be added to the kit is a  X10 amplifier to drive the CMOS divider IC.

Not bad for $21    :-)

73
André N4ICK





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