Driving the BFO from a spare Si5351 clock is the ideal way to do it. ?Makes it trivial to flip between USB and LSB without affectng drive level of the VFO, and also allows an easy choice of 5mhz vs 19mhz for the VFO. ?We badly need this integrated into the "standard" firmware. ?
Here's the thread where Pete posted how he did it. ?/g/BITX20/message/24270? ? Some issues left unresolved there. ?What's the best way to drive the BFO (and VFO), should we all move to the resistor network from the uBitx? ?
John Smith wrote:
> ?Getting the BITX40 to do something else other than simple phone mode on 40 meters
> ?would require you to rebuild it in a different way. Such as the row of four toroids is a
> ?passband filter for LSB. You would need to change them and some other parts to work
> ?on USB. And then not on LSB anymore. Not just change it in the code.?Rebuilding it
> ?is doable. But if you can do that, then you can make it that way to begin with.
No.
It's a wire from Si5351 to the BFO and a sketch change.
John also said:
> ?CW on sideband might be legal somewhere, not in U.S.
Nobody here has ever suggested transmitting A2A morse code, you get A1A whether you feed a pure sine wave into the microphone input or somehow generate RF directly as Farhan does on the uBitx. ? The latter is preferable. ?If using the former, then the tone, the microphone amp, and modulator must all be perfect to get the that same clean A1A transmission, and shaping the keying envelope is easier with the latter..
Jerry, KE7ER
On Thu, Apr 6, 2017 at 10:31 pm, peatmoss - ki6ssi wrote:
FYI I've been working digital for a few weeks now. I replaced the bfo with an extra clock from the raduino but what you are doing should work fine.
?
