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Title: Knightkit V44 VFO Output Post by: w9bea on March 24, 2017, 02:09:02 PM Good Afternoon All:
I was wondering what I should expect as far as RF frequency output and amplitude out of a Knightkit V-44 VFO? The manual does not tell me specifically what the fundemental RF output is; just rather tells me that it cover 80-10, and that the output is more than enough to excite the oscillator in a transmitter. OK. I am aware that it multiplies upwards depending on the intended xmit frequency via harmonics. Just got done "rekitting" a basket case VFO, am about put it o the shelf and go to work on a soon to match transmitter.... Just want to make sure that the frequency output spec and RF level out is correct for this Clapp type Oscillator/Buffer. Appreciate the insight. 73--Wally W9BEA Title: Re: Knightkit V44 VFO Output Post by: WD5JKO on March 24, 2017, 05:22:55 PM Wally, The VFO is always running on 160m, and the buffer stage acts somewhat as a doubler. The RF output coils resonance is dependent on the VFO load capacitance, and cable (much like the Johnson 122). On a scope, open circuit is a complex waveform full of harmonics; it is not a sine wave. As I recall, the amplitude is upward of 100v P-P when connecting a 10X scope probe to the crystal plug pins. It is worth repeating, the VFO is always on 160m, and the output has a strong 80m output (rich in harmonics), no matter if the VFO knob is on the 80m, or 40-10m position. Getting on 10m with this VFO means 16X frequency multiplication. I also believe that the two output coils in the back are identical. Jim Wd5JKO |