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Problems with audio tones (in RX) with uBitx v #ubitx #v5

 

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Hi everyone,
I hope someone can help me troubleshooting my uBitx v5. After wiring up the board I got ?almost no reception on the amateur bands, therefore I upgraded the firmware to CEC 1.2 and adjusted the BFO to 11.056.255 Hz.

After these changes I am able to receive signals and get reasonable audio output, however, at every (~15.9 KHz) I do get a loud audio tone. The tone pitch shifts up (with LSB) when I increase the tuning frequency. When switching to USB I believe the tone shifts 3 KHz up, in USB the tone pitch lowers when the tuning frequency increases.


The frequency of the tone changes also (proportionally) when I adjust the BFO frequency or when applying an IF shift.


Also tried to trace back the issue, when I ground TP20 the tone disappears, however, when I ground the input of the 11,059 Xtal filter (TP17) doesn¡¯t have any audible effect on tone.


Thanks! Albert

PA2AF
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