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Raduino for bfo?

 

Anyone modify their bitx to use the raduino for the bfo? If so any
specifics on how to connect the output to the board? My goal is to be
able to flip between USB/LSB in code. The current code that flips the
vfo to 19 MHz does not seem as sensitive.

73's
Pete
 

As far as wiring it up, I'd use the uBitx example: ?

What do you mean by "less sensitive". ?On receive? ?Transmit or receive, it's possible the analog BFO needs to be adjusted in freq to get the crystal filter centered properly. ?Also possible that the first mixer doesn't work quite as well with a VFO at 19mhz as it does at 5mhz.


On Tue, Mar 14, 2017 at 04:20 pm, peatmoss wrote:

Anyone modify their bitx to use the raduino for the bfo? If so any
specifics on how to connect the output to the board? My goal is to be
able to flip between USB/LSB in code. The current code that flips the
vfo to 19 MHz does not seem as sensitive.

?
 

In answer to your question: ?Not me.?


On Tue, Mar 14, 2017 at 04:25 pm, Jerry Gaffke wrote:

Anyone modify their bitx to use the raduino for the bfo?

?
 

Thanks, in receive, have not tried tx yet.
 

Yes I have, removed the 12mhz crystal, tapped the signal onto the emitter of q11 from one of the two extra outputs on the raduino. ?Took a while of trial and error to get it's output near the correct frequency. Not necessarily hard to do software wise. All I've done so far is just get the thing back to working conditions and I'm not entirely happy with the outcome so far. That being said this is above my electronics knowledge so I'm kinda "fudging it til I make it". ?I haven't tried getting it to swing the bfo to do usb yet. I've been too busy removing snow here in upstate NY.?
 

Thanks for the information! So why are you not happy with the outcome?
 

Got it working, tapped in just after c106 and used the ground for the missing variable cap. I'm still working on getting it tuned up. Its off frequency and not sure why. I'm using this formula to tune, clk0 is the bfo.

void setFrequency(unsigned long f){

? if (isUSB){

? ? si5351.set_freq((usb_bfo_freq - f) * 100ULL, SI5351_CLK2);

? ? si5351.set_freq((usb_bfo_freq) * 100ULL, SI5351_CLK0);

? }

? else{

? ? si5351.set_freq((bfo_freq - f) * 100ULL, SI5351_CLK2);

? ? si5351.set_freq((bfo_freq) * 100ULL, SI5351_CLK0);

? }

? frequency = f;

}

Added a pic where I attached a mini coax to go to the raduino
 

I'm stuck exactly where peatmoss is. Infact we came up with the same code almost line for line. I am also off frequency and trying to find the best BFO freq that works and sounds the best. I am at the point where I need to hook up my PC to it and feed it an exact tone or two to align it.
 

I finally got the high side vfo code working by removing c91, c92. I found if left in place the vfo did not work above ~10MHz. So if anyone is planning on using the commented out USB code in the original file you will probably need to do the same.

Raduino bfo is now working, LSB sounds great but still need to test USB. Also still works well down on 75m.?

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