I've been tinkering with a phasing exciter that uses easy-to-get parts and
produces a very clean signal from the sound card quadrature outputs in Jason
and SpecLab. A preliminary schematic (hand-drawn, DL4YHF quality <g>) is at:
http://www.w1tag.com/files/Exciter.jpg
The "left" and "right" inputs from the sound card are at the upper left. A
4X L.O. input is at the lower left. The output on the right is +8 dBm for a
1.5 volt p-p audio input. Power is 12 VDC, not critical, but stay above 11
VDC.
Present specs at +9 dBm output are:
Carrier: > 65 dB suppression
LSB: > 52 dB suppression
All other: > 50 dB below the carrier.
I'll get this drawn and written up later in the week. Questions about my
sanity are welcome. Credit is due VK3BHR for several ideas in the article
posted at:
http://ironbark.bendigo.latrobe.edu.au/~rice/ssb/ssb.html
John Andrews, W1TAG/WD2XES
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