[WL-USERS] That old PTT signal again

Jerry Pixton jpixton@shentel.net
Thu, 10 Jun 1999 20:19:32 +0100


All,

I have finally gotten around to experimenting with the Digital Voice System
connector on my FT1000mp. This little unit records and plays back 4 second
audio clips. I wanted to use that connector to get mike audio out to the
sound board and to feed wave file audio back into it for SSB. The FT1000mp
nicely does all the switching of audio as you change the mode switch from
LSB, USB, RTTY and PKT . But I thought it looked too easy. It turns out
that you need an enable gate signal (high) during the playing of a wave
file and another enable signal to get mike audio out to the connector.
These signals are generated internal to the DVS2 unit that plugs into this
connector. 

So I went looking at where to find such a signal (looks just like a PTT
signal to me) all I would need to do is isolate it and keep it positive
going instead of negative. I even see in the WriteLog ini settings how the
PTT polarity can be inverted.

I now think I understand what Wayne has said several times.

In RTTY, you can get three different sources for a PTT signal

1. If you are using a Rig interface (on Comm2 in my case) WL will command
PTT on and off if the rig can (Yaesu do, ICOM does not)

2. You can enable pin 16 on one of your parallel ports (LPT1 in my case)

1 and 2 are set up using the Port Setup screen from the WriteLog window.

3. And by going to rttyrite window and the port menu you can select another
port (different from the one doing Rig interfacing) then RTS and DTR are
asserted high for PTT

But in SSB there seem to be only two sources since the rttyrite window has
to be closed and so WriteLog knows nothing about that port.

1. The Rig interface will command PTT on while a wave file is being played
and then off at the end. 

OR

2. The LPT port pin 16 can be used.

This seems to mutually exclusive unlike the rtty case. I can not get both at
the same time in SSB. I did not suspect this. I thought I would at least
get both at the same time. Is something wrong in my setup????

This sounds very much like several messages where PTT seems to work in rtty
and not in ssb.

My desire is to let WriteLog continue to command the Rig interface for
transmit when a wave file is played in ssb modes and I will push the foot
switch when I want to use the headset mike thru the sound board. I want to
use the PTT signal on LPT1 to enable the wave audio coming in thru the
digital voice connector.

BTW. I have been doing this last set of test using the AF (audio) output
connector (constant voltage) to the sound board Line In and the Patch In
from the sound board Line Out.  I am running my Heil mike directly to the
sound board Mike In. Now using the SB16 board (got tired of interference
from PCI128 card)

You can still put the mode switch in PKT to get proper bandpass response
for rtty with this connections.

Jerry, W6IHG

------------------------------------------
Dr. Jerry R. Pixton, PIXOS Designs
http://www.pixos.com/designs/
jpixton@shentel.net
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