[WriteLog] Mmtty drop out

[Connie Marshall]

Hi Ed, no not the Radio PTT or the 165C software.... was worth a try though.

You can hear what the problem sounds like by loading just a %E in a msg
buffer and playing it. Radio comes on and you here the tone for a split
second. I'm not saying it has anything to do with %E but that's just a way
to hear what happens.

If you have ever noticed the random garbage characters that occasionally
appears (not RX garbage) when you hit a message key. They are blue in color
just like the other TX Msg characters. These garbage character sometime
appear when no failure occurs, but always seem to appear when it does fail.

It seems that it has something to do with the sound card Buffer or maybe the
loop back. If I turn the RF gain down on the Receiver, so the Sound card is
not printing anything, the problem seems to go away (of course can't do this
in real operation). Sometimes I can go 30 mins or more with out a failure,
sometimes it might happen 2 or three time in 5 minutes, so it is difficult
to trouble shoot.

Connie

K5CM

-----Original Message-----
From: writelog-bounces at contesting.com
[mailto:writelog-bounces at contesting.com]On Behalf Of k4sb at bellsouth.net
Sent: Wednesday, November 16, 2005 11:18 AM
To: writelog at contesting.com
Subject: Re: [WriteLog] Mmtty drop out


Only a suggestion, but of course MMTTY will drop back to receive if PTT
is no longer asserted.

Perhaps a check of the circuit going to the PTT plug would be in order.
It could be the required voltage to keep PTT asserted is just too low.

On a Kenwood I used, I had this problem, and solved it by adding a
resistor from the PTT circuit to ground. ( on the Collector-Emitter )

Had to keep trying different values as the PTT would activate if the
resistor value was too low. Finally found a value which would not key
the PTT, but when the serial port RTS was asserted, things went fine.

73
Ed
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