[Elecraft] TX/RX Discrepancy

[Trevor Day]

Hi All,
Continuing from yesterday, I have carried out Cal PLL on all bands.
When carrying out the Rx Mode SSB Filter test from p15/16 of the KSB2
manual, to get the LSB BFO freq of 4913.5, the BFO parameter is 160 ie.
BF1t160L (This seems too high?)  When I try to set the USB frequency of
4916.30, I can only reach 4916.24 equating to a BFO parameter of 255
(the upper limit).

Looking at spectrogram, when I have Cal Fil enabled, the passband of the
filter is centred around 800 Hz, tailing off at around 300 with a
gradual drop off on the high side to 2500 Hz.  When I disable Cal Fil
(revert to freq display) the passband shifts left and changes shape
becoming almost a CW response centred on 500Hz, dropping low to 0Hz and
high to 1kHz.  I have checked that this is the same filter (Op1)
selected in both cases.

Just to remove one variable, I have exchanged the KSB2 with my own after
doing the checks below, but before doing the checks above, and found no
difference. In other words, I still saw a frequency discrepancy between
tx and rx. The KSB2s are now back with their respective units.

I remain somewhat puzzled.....help!

Thanks,
Trev G3ZYY #1330 (a Nightmare)
              #2637  (Works perfectly).

In message <UlgGOoI1NdL+EwpW@trevday.eurobell.co.uk>, Trevor Day
<Trev@secornwall.com> writes
>Hi All, just a brief update before I go to bed !  I bit the bullet and have
>done a factory reset followed by a Cal PLL on 40m only.  I have not
>entered any other new values, but I would not expect them to alter the
>relative tx/rx frequencies anyway.  The result is a +400 Hz Tx offset on
>LSB and a
>+1kHz Tx offset on USB!!  Nominal frequency 7050 kHz.
>
> I'll go through a complete setting up routine tomorrow and let you know
>the outcome.

-- 
Trevor Day