[Elecraft] K3: data modes - bizarre behavior

[Bill Conkling]

Well, this is normal for digital mode DATA A.  I'm not familiar with your
particular software, but for PSK31 and similar modes, the K3 VFO A is set to
a frequency for the carrier.  The audio is on the upper sideband, and is
centered in the 3 KHz passband which is 1.5kHz up from the carrier.  Thus
the offset.  Some digital software has an allowance for an offset, but I'm
not sure about yours.  You might check on this.

Typically if operating on 20 meters with radio set to 14.070MHz, the
waterfall will be full of traces at audio frequencies spread across the
passband of your radio.  So you actual transmission freq is the sum of VFO
plus the audio.

...bill  nr4c

-----Original Message-----
From: Matt Zilmer [mailto:mzilmer at verizon.net] 
Sent: Sunday, January 01, 2012 11:31 AM
To: elecraft at mailman.qth.net
Subject: [Elecraft] K3: data modes - bizarre behavior

In all this time with K3 #24, I've never been stymied by any issue
such as described below.

I'm a Navy-Marine Corps MARS member.  We use RMS Express in the WL2K
system on HF, running WL2K Winmor mode  The software I have is version
1.1.3.0.  

I also use LP Bridge to create two COM ports: one used for DTR (PTT)
and the other for control, COM19 and COM20 respectively.  The sound
card is an EMU 0202.

The problem is this:  When RMS Express takes control of the K3,
calling an RMS node on HF *always* results in the receive frequency
being 1.5 KHz too high.  I've had to rotate the RIT between call-up
transmissions to get the RX on frequency before the initial 5 attempts
time out.  The TX frequency seems dead-on, because the RMS always
answers - but RX is 1.5 KHz high.  And yes, I've tested with multiple
RMS nodes, including my own NMCM RMS here at the shack.  Same problem
occurs with each, so it's a setup issue with software or the K3 here.

RMS Express sends the following commands after it's set the COM20 comm
parameters:

	FR0;	# cancel split
	RT0;	# RIT OFF
	XT0;	# XIT OFF
	MD6;	# TX DATA mode
	DT0;	# DATA A sub-mode of TX DATA

The sequence above is sent once at the beginning of an RMS Express
call-up of the remote node.  Only COM19's DTR is used to assert PTT
for transmissions.

Just for grins, I checked the various meta-modes the K3 is in.  I
discovered that even though AI is set to ZERO, I'm still getting IF
annunciations back from the K3.  Odd, that.

	K31;	# K3 extended commands enabled
	K22;	# K2 extended " "
	AI0;	# AUTOINF OFF

Since split and the incremental controls are off and ZEROed, I'm
totally blind to what's going on.  VFO A is on the correct frequency
in each case (for each RMS Node), which means to me that RX and TX
actual frequencies should be the same.

Any ideas what's causing this?

73 and HNY,
matt W6NIA, NNN0UET


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