[CQ-Contest] A portable rig for contesting?

Mark Bailey kd4d at comcast.net
Thu Oct 6 06:16:42 EDT 2005

Bill Coleman wrote:
> On Oct 5, 2005, at 11:36 AM, VR2BrettGraham wrote:

> So, if the goal of CW PTT is to avoid hot-switching the amplifier, it  
> is not necessary with the K2.
> An alternative question would be - exactly what function is achieved  
> with the CW PTT?

Well, in the stations I operate at, PTT with CW typically
1)  Prevents hot-switching the amplifier
2)  Switches the receive audio to the non-transmitting radio
automatically in both ears when doing SO2R
3)  Allows quickly switching to receive (without the VOX delay)
at the end of computer CW messages for non-QSK amplifiers.
(Otherwise you need to adjust the VOX delay to not
drop out between characters (and even words) to prevent
having the amplifier unkey constantly.  This can cause
you to miss the first character of calling stations).
4)  In some multi-operator configurations, PTT is used
for "lockouts" which prevent two simultaneous transmitted
signals or to share a single amplifier between two radios.

I think that's it.

It's just like those who PTT and a foot switch for SSB
instead of VOX.  Does the same things...

I usually generate PTT from the computer parallel port
and feed it to the radio through a two-radio switch box.
It does the same things for CW and SSB.  In SSB,
it is typically fed in parallel with a foot switch.

On old Orion firmware, I actually ended up "ORing" it with
the radio output.  The Orion has added a PTT feature for
CW to the firmware.  Most of the amplifiers I use won't
survive a weekend of QSK...

NOTE:  I am a guest operator and don't have a station at home.


Mark, KD4D
> Bill Coleman, AA4LR, PP-ASEL        Mail: aa4lr at arrl.net

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