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V6 Birdies? (spurious signals) #v6

Bill
 

Got my V6 assembled and tested and have been playing with it. I haven't made any QSOs yet, but have been using it for SWL and setting up WSPR and receiving digital modes. I'm very happy with the build quality and the case. The mic works just fine. Power out (into a dummy) is nearly 15 W PEP(!) at 80 M, dropping to 4-5 at 10 M. Frequency is spot-on. I've tuned the BFO using Jim W0EB's advice and the HFSignals BFO tuning aid. I am looking forward to the screen display speed improvements. :-)

I am having trouble with some spurious signals that unfortunately are interfering WWV on 2.5, 10, 15, and 20 MHz. I get prominent whistling on each of those even with a dummy load on the antenna. At 10.000 MHz the tone is 2136 Hz, if that is any clue. Have I done something wrong or is this just the way it is? Is there anything I can/should tweak to move or reduce the birdies?

Thank you,

- Bill KB3T

Ashhar Farhan
 

Bill,
These birdies are an unfortunate fact of life for a dual conversion set like this. As each crystal of the arduino(16 mhz) and of the si5351 (25 mhz) is different by a few hertz, some multiple of one beats with a multiple of the other to produce these. However, they are never as strong as the ones you report. The strong ones are few they occur at odd places in some bands.
Can you check that these are not emanating from othe nearby devices?
- f


On Mon 6 Jan, 2020, 6:06 AM Bill, <groups191227@...> wrote:
Got my V6 assembled and tested and have been playing with it.  I haven't
made any QSOs yet, but have been using it for SWL and setting up WSPR
and receiving digital modes. I'm very happy with the build quality and
the case. The mic works just fine.  Power out (into a dummy) is nearly
15 W PEP(!) at 80 M, dropping to 4-5 at 10 M.  Frequency is spot-on. 
I've tuned the BFO using Jim W0EB's advice and the HFSignals BFO tuning
aid.  I am looking forward to the screen display speed improvements. :-)

I am having trouble with some spurious signals that unfortunately are
interfering WWV on 2.5, 10, 15, and 20 MHz.  I get prominent whistling
on each of those even with a dummy load on the antenna. At 10.000 MHz
the tone is 2136 Hz, if that is any clue.  Have I done something wrong
or is this just the way it is?  Is there anything I can/should tweak to
move or reduce the birdies?

Thank you,

  - Bill KB3T