11. Potentiometer tuning for the Ultimate3


Hi Hans,
I added the U3S section 11. Potentiometer tuning for the Ultimate3 modifications to my v3.12 version but am getting problems. This is a U3S Transceiver using standard U3 Tx with relay switched LPFs and a standard Rx module with Polyphase board and 7MHz BPF fitted.

I have set Tn mode = 1 in the menu.

Problems are;
1) Upward frequency tuning only in Tx WSPR mode. I can hear clicking on my monitor Rx when the Tune pot is turned to min but the frequency does go lower.
2) In RX mode, upward movement of displayed frequency only, but it does not actually change the LO frequency (using 7mhz band). NO downward frequency either.
3) Loud clicking on Rx audio once pot is away from centre setting (in freq up or down positions)

I measure approx 0.5V on S1 with Tune pot at minimum, and approx 4.5V at max setting, and 2.5V in centre position.
Both S1 and S2 switches functioning ok.

I tried a complete 'RESET' and re-configured all my settings
I have used a 10k linear tune pot with 1k resistors.

Any ideas what may be wrong please.

73 Ken G4APB

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