I hate to rain on this nice Pixie 2 parade, but for those of you who have
built this puppy up AND have oscilloscopes, check the power output. I
knocked one together dead bug style last nite, and into a dummy load the
waveform is Ugly. Even with the low pass filter, the waveform is still
I wondered about the 300 mW claims, and tried all manner of PA (2N3053,
2N3866, MRF 472, 2N3019) and could only get 300 mW out if running 24 volts on
the supply. I will try a 2N2222A as the PA tonite. (Will also play with the
oscillator, trying a metal can '2222A, and an MPS 6521 to replace the plastic
'2222 that is there now).
So my guess is either all my transistors are junque (they did come from the
junque boxe), or those ugly waveforms are giving the usual 'ugly waveform
enhancement' to the wattmeter reading.
Ah, Devil's Advocate! Comes from too many readings of Morrison and Boyd in
college! Let's get some scopes on those pixies and see how they perform.
73, Jim N0OCT
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