2m VCO?
i'm after a circuit for a 2m VCO.
basically i'm planning to homebrew a kind of tracking generator, where I can
sweep across 2m to look at filter shapes, etc.
my plan is to sweep, using a vco, across 2m using a sawtooth waveform. this
waveform will also be amplified and fed to an oscilliscope, to give me a
horizontal sweep.
the output from the filter will then be fed to a RF millivoltmeter circuit
(again, anyone got any good circuits?) and this will then be fed into a
logarithmic converter then be put onto the Y deflection, to give me
amplitude.
calibration will be by putting the system into "manual" mode and connecting
to a frequency counter, then sweeping up and down until get specific
frequency, then the x-centering be used to set this on a known point.
basically anything that having say 1-6V in giving a 140 to 150mhz sweep
would be grand, then i can play with amplifiers to get it just as i want.
thanks all!
dr. x
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