W4TV and W3FPR got me down the right path. I forgot that it is a pulse on RS232 pin1. Got the scope out and it is fine. Thanks Don. Got to get me one of those small, lightweight scopes.
I had both transistors in the RS232 shell (FSK keying and PTT) and when I opened the shell it looked like I had not hooked up the transistor to pin4 of the Acc plug. Actually I must have cold soldered the lead and it broke free after several years. When I first looked at the lead it seemed I had unsoldered the lead and insulated it. That is why I had thought I was keying without the PTT. But as Joe pointed out, no way. Back in business. Thanks for the help. 73, N2TK, Tony -----Original Message----- From: Elecraft [mailto:elecraft-boun...@mailman.qth.net] On Behalf Of Joe Subich, W4TV Sent: Thursday, July 14, 2016 11:30 AM To: elecraft@mailman.qth.net Subject: Re: [Elecraft] K3 - MMTTY interface for FSK > All along I have been using COM 1 on my PC for FSK keying. I have been > using pin 3 to Pin 1 on the Acc K3 socket. I have not used Pin > 7 (PTT) to Pin 4 on the K3. I trust you have been using an NPN transistor between the RS-232 output (+/- 9V) of the serial port and the TTL input (0 to +5V) of the K3 ACC port. If you are not using Radio Command and have not connected Pin 7 of the serial port to pin 4 of the K3 (again using an NPN transistor), I do not know how the K3 would ever switch to transmit. 73, ... Joe, W4TV On 7/14/2016 10:45 AM, N2TK, Tony wrote: > I am having brain freeze. I must have changed something but not sure what. > Both K3's had been working fine on FSK using MMTTY for years. I can > still receive fine, but I can't transmit on either. > > I am using LP Bridge which is talking fine to either K3. > > When I hit Xmit in MMTTY the program shows it is sending, but it does > not key the K3. > > > > All along I have been using COM 1 on my PC for FSK keying. I have been > using pin 3 to Pin 1 on the Acc K3 socket. I have not used Pin 7 (PTT) > to Pin 4 on the K3. > > When I measure voltage on Com 1 pin 3 it is -9V. When I hit Xmit in > MMTTY it stays at -9V. > > > > MMTTY is setup as follows: > > - Misc tab - COM-TxD (FSK) > > - TX tab - Port Com1. > > - I am not using Radio Command > > > > K3 > > - PTT-KEY is OFF-OFF. > > One K3 has KIO3A using RS232. The other has KIO3B using USB. > > > > Also if I ground pin 4 on the Acc socket it does not transmit. > > Tried another Com port and made the change in MMTTY but the same result. > > What could I have inadvertently changed so that the Com 1 Pin 3 to > stay at -9V? > > > > Tnx for any feedback. > > N2TK, Tony > > ______________________________________________________________ > Elecraft mailing list > Home: http://mailman.qth.net/mailman/listinfo/elecraft > Help: http://mailman.qth.net/mmfaq.htm > Post: mailto:Elecraft@mailman.qth.net > > This list hosted by: http://www.qsl.net Please help support this email > list: http://www.qsl.net/donate.html Message delivered to > li...@subich.com > ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to tony....@verizon.net ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
