[Elecraft] K3 - MMTTY interface for FSK

[Don Wilhelm]

Tony,

If the com port pin stays at -9volts, then the COM port is not "doing 
its thing".
I trust you used a 'scope to look measure it.  A DMM will not likely 
respond quickly enough to see the positive going pulses.
Try another COM port.

73,
Don W3FPR

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.
>
>   
>
>