Tx response – not more than –6 db 400 to 2600 hz.
Rx response - -6 db. 2.2 kHz or better, –60 db.
4.5 kHz or less
The above are the specs for my modest HF radio.
The latest WSJT-X v1.2 r 3556 boasts dual mode and to support it, split
A typical setup would have the radio VFO A set to 14.076 Mhz.
I would be able to hear signals from just above 14.076 MHz to roughly
Assuming I am NOT setup for Split operation, my tones would be effective
for roughly the same range.
So far, its all good.
The way this program is supposed to work, JT65 is assumed to be from
14.076 to about 14.078 and JT9 from
there up. The default setting for the BLUE LINE is 2500 which would
correspond to 14.078.5 Mhz. It can be moved.
Without split operation, I can hear all the JT65 stations, or all the JT9
stations, or I can straddle both of them by
setting my dial at 14.077 and setting the Blue Line at about 1500 hz. It
works, so far. No need for split.
If no one had mentioned SPLIT operation, I would have been a happy little
We all know this is Joe’s fault, he is on holidays, so he can’t banish me
for saying so.
Its his fault.
Suppose I was the proud father of a radio with a 4 MHz receive bandwidth
but with a Tx bandwidth of only 2.6 kHz.
Lets suppose further than the low frequency response sucks below about
How can I manage to monitor from 14.076 all the way up to 14.080 MHz in
one shot and Tx for the same span too
without having to touch anything?
This is where SPLIT comes in.
VFO A is for receive, VFO B is for transmit.
You make sure both VFO’s are in the same mode, usually pressing the VFO
A=VFO B button will do it. Also press SPLIT.
In version 1.2 r 3556 the Tx tones vary between 1500 to 2000 hz in split mode. That’s right. Read
the manual, connect the output to a speaker to prove it,
hook it to a scope.
Suppose the station you want to work is coming in at 610 hz on the
waterfall, (14.076Mhz + 610 hz). 14.076610 MHz is the frequency of the sync
To answer him, your VFO B needs to be 14.075. Add 1610 (the actual tone)
to that and you have 14.076610 MHz, which is perfect.
Likewise for any other segment.
I use COMMANDER C:\DXLab\Commander\Help\index.htm to do the magical radio
control. Some radios are more agile. This works for the FT450.
Is anyone following this?
Feel free to stone me.