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Old 30th Sep 2017, 3:39 pm   #1
Wendymott's Avatar
Join Date: Jun 2013
Location: Huddersfield, West Yorkshire, UK.
Posts: 840
Red face SSB Signal Generator

Hi peeps...... While messing about building My 40M SSB transceiver and subsequent Multiband SSB transceiver.... I found that I needed a definitive SSB signal, both of a known frequency and output level. As I could see no commercial equipment ..... " I am sure there must be some"..I decided that I would build one.
It is based on my Multiband transceiver TX exciter, but is dedicated to Low output levels suitable for receiver inputs. I had tried using my FT817 with lots of attenuation... but somehow it seemed like using a "steam hammer" to open a walnut.
I will post the other modules as they become, proven, but for now the Bandpass filter block is up and running.
I decided upon 80 m - 10m.. UK bands only... leaving out "Top band" as I have no use for it.
Thanks go to Jeremy G0HZU for the 40 M filter design, and me for the others. The Multiband RX/TX had Micro relays to switch the bands, but this version uses BA282 diodes, much cheaper, but power limited. I used BC547's to buffer select each band as the micro controller grounds the selected band pin.
Hopefully the schematic will be readable, but if not, i can PM anyone interested. All filters were aligned using my ROGOL spectrum analyzer with tracking generator. If anyone is interested I can post the display waveforms.
As it is a long term project, it may be a while before "part two".
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Should get out more.

Wendy G8BZY
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