I agree that using WWV to align the TXCO/crystal oven (VI+/VI) is faster and
better than using a frequency counter, but....
The original post I replied to was from a ham who had dinked with his BFO
trimmers on the TX Audio board and NOT the TXCO itself. If you have messed
with the BFO trimmers, then you can't count on adjusting the TXCO to fix
this... you're just compounding errors. If all you have done is to mess
with the BFO trimmers, then get THEM back to a point where they are in sync
with the TXCO... and then you can zero the TXCO. As John KH7T said, do NOT
try to use the TXCO to adjust for BFO trimmer errors.
Considering that the USB trimmer affects the frequency at which you will
hear the WWV beat note in CW mode, it would be awfully hard to align the
TXCO/BFO trimmers on an Omni VI/VI+ without using a frequency counter. I
think it can be done IF you have an HF digital mode program (like Digipan or
MixW) that has a waterfall display so you can see the effects of your
adjustments. I know it can be done if you have another transmitter and an
additional receiver.
I'll play with my VI this weekend and come up with a procedure for aligning
the TXCO and USB/LSB BFO trimmers using only WWV, and a means of aligning
the CW Transmit BFO trimmer via the use of TWO other radios (a transceiver
and another receiver or transceiver). Most hams have numerous rigs, but no
test equipment.
Here's a question for those who have owned both the VI and the VI+... I
understand that the VI+ has a different TX audio board, and uses the
crystals differently. Anyone who has/has had both care to comment? I'm
particularly interested in whether the LSB crystal is used for CW transmit
on the VI+. I also understand that there was a mod (maybe not factory
approved) that changed which crystals were used for what modes... anyone
know anything about that?
- jgc
John Clifford KD7KGX
Heathkit HW-9 WARC/HFT-9/HM-9
Elecraft K2 #1678 /KSB2/KIO2/KBT2/KAT2/KNB2/KAF2/KPA100
Ten-Tec Omni VI/Opt1
email: kd7kgx@arrl.net
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