[Elecraft] K3: external VFO control

[Holger Schurig]

Controlling the VFO A (or B) is easy from software. Just refer the
Author to the K3 & KX3 Programmers Reference Manual.

http://www.elecraft.com/manual/K3&KX3%20Pgmrs%20Ref,%20E2.pdf

(PS: I'd wish Elecraft would stop using & and spaces in file names. &
is a nuisance on the Linux command line, because it normally sends
programs into the background ...  once can escape them, so it's not
really a harm, but still a nuisance. The same for spaces. Those %20
simply look ugly in URLs)


Okay, back to topic. Here's an excerpt from that document:

FA and FB (VFO A/B Frequency; GET/SET)

SET/RSP format:  FAxxxxxxxxxxx;  or  FBxxxxxxxxxxx;  where xxxxxxxxxxx
is the frequency in Hz. Example: FA00014060000;  sets VFO A to 14060
kHz. The Hz digit is ignored if the K3 is not in FINE mode (1-Hz
tuning; use SWT49). If the specified frequency is in a different
amateur band than the present one, the K3 will change to the new band,
and will automatically report the new values of parameters that may
have changed 7
. Notes: (1) Band changes typically take 0.5 seconds; all command
handling is deferred until this process is complete. (2) If the
specified frequency is over 30 MHz and is within a valid transverter
band (as specified by the operator using the K3's XVTR menu entries),
the K3 will switch to that transverter band. If the specified
frequency is outside the range of 500 kHz-30 MHz and 48-54 MHz, the K3
will switch to the amateur band closest to the requested one, and the
last-used VFO A and VFO B values for that band will be retrieved.
If the VFOs are linked (non-SPLIT), FA also sets VFO B to the same
frequency as VFO A.



So, basically the software sends  SWT49;   (note the semicolon) to the
K3, and whenever it needs a new VFO A frequency, it sends
FA00014060000; (again note the semicolon).

Simple, eh?


Holger, DH3HS