Wayde VA3NCA Receives SSB, CW, FT8, and CHU Canada on his SolderSmoke Direct Conversion Receiver

Above you can watch and listen to Wayde's receiver as he tunes across 40 meters. It sounds good, even though Wayde is thinking about some improvements. 

 It was highly appropriate that Wayde's first reception report should be of CHU Canada, the Canadian time signal on 7.850 MHz, a bit above the 40 meter band, but clearly in tuning range for an unmodified SolderSmoke direct conversion receiver.  CHU is probably unique in the world in that it is transmitting the carrier and JUST ONE SIDEBAND.  It transmits only the upper sideband.  This makes it clearly detectable by our receiver.  As Dean pointed out to Wayde, all he had to do was "zero beat" the carrier with the PTO signal (tune to the point where they are on the same frequency and the audio tone disappears).   Because there is only one sideband, the direct conversion receiver can demodulate it very well.  If there had been two sidebands, this would have been a standard AM signal, and our little receiver -- which does very well with SSB and CW -- would have been unable to demodulate the signal without distortion. (For an explanation of why this is, see: https://soldersmoke.blogspot.com/2022/12/but-why-why-cant-i-listen-to-dsb-or-am.html   Warning -- this is kind of in the "advanced course" category.)

Here is an overhead shot of Wayde's receiver: 

This is a really nice build.  The use of what appears to be a kitchen cutting board harkens back to the early days of radio when young hams took the cutting boards from their mothers' kitchens and used them as bases for rigs.  This is origin of the term "bread board."  Frank Jones continued in this tradition by building most of his rigs on wooden boards.  Wade's DC receiver continues in that tradition. 

Wade was able to decode some FT8 picked up by this receiver and recorded on his phone: 

Congratulations Wade!   

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Documentation on Hackaday:

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