[Elecraft] K2 w/KSB CW reverse BFO

[Wallace, Andy]

> -----Original Message-----
> From: k6se@juno.com [mailto:k6se@juno.com]

> Andy Wallace wrote:
> 
> "I set my K1 frequency calibrtion on a separate receiver such that the
> display reads the transmit frequency, so I know I am always in-band."
> -----
> K6SE's reply:
> 
> That's a good practice if you're close to the band edge.  I 
> assume that the K1's VFO readout accuracy is subject to 
> the same problems as the K2 frequency drift with temperature.
> ==========

Yes, I suppose it does, though with the K1 you are not going to be
running PSK31 or even SSB, so it's not as much of an issue. I've never
noticed any problems of BFO drifting out of the filter like you've seen
with the K2, either, but I am not running the rig in temperature extremes. 
I would say at room temperature from turn-on to 15 minutes later it is
100 Hz or less. I've built my K1 for about 80 kHz band coverage.

> K6SE's reply:
> 
> On CW, being close to zero beat is important because the 
> station you are
> calling may be using his receiver's 250 Hz filters and he may not find
> you unless he uses his receiver's RIT.  If your frequency is offset by
> 600 Hz (as you described above), you'll even be outside of his 500 Hz
> xtal filter passband.  It is especially irritating to 
> operators during CW
> contests when calling stations are not close to zero beat.

I believe that alignment as described above does put things in
the correct place -- transmit freq exactly as shown (verified on another
receiver) and receive freq matches because I have done the BFO and
offset adjustment correctly. I guess my point was that I found it
easier and more sensible to use an external receiver to calibrate
the K1 transmit frequency, rather than using an external transmitter
to calibrate the K1 receive freqency and then adjust the offset, as the
manual (I believe) states. Bottom line is that the net result is the 
same. 

> If you notice that you have to use your RIT on most stations answering
> your CQs, that's a good indication that your receive and transmit
> frequencies do not coincide while your RIT is off.

Nope, don't have that problem at all -- hundreds of QSOs and the only
time I use the RIT/XIT is to work split, or perhaps the guy with the 
drifty HW-101 as in this past weekend. ;-) 

It looks like my K1 method works, and you've settled my concerns about
the K2 working in a logical fashion. Thanks!

-Andy