[Elecraft] When Transmitting on FT8 - KPA500 has issues - KD8ZYD

[Ken Winterling]

Fred,

Does this condition also happen on SSB, RTTY, CW or only while running
digital mode?

Is it possible the PTT/key line is being dropped?  When the power drops is
there an asterisk (*) on the left side of the KPA500 display?  An asterisk
will appear on the left side of the LCD display if there is a valid PA KEY/
PTT signal is being received from the transceiver. If there is no asterisk
the amp isn't receiving a valid PA KEY/PTT signal from the transceiver.  If
there is an underscore instead of an asterisk it means that the amplifier
keying is being inhibited by a low signal on pin 11 of the AUX connector.

Ken
WA2LBI





On Mon, Jul 1, 2019 at 9:06 PM Fred <thegoeckel at gmail.com> wrote:

> Hi,
>
> I have a K3, P3, KPA500, KAT500 and a SignaLink for sound.  Sometimes when
> I transmit on FT8 running full power on the KPA500, the KPA500 will click
> on/off.  The power doesn't turn on/off, it seems like a relay inside.  The
> power meter will go to about 500 watts, then down to 0, then to abut 500
> watts...and down to 0 maybe once a second.  I have a short video I can send
> if someone would like to see it.  When I bypass the KPA500 and use 50 watts
> or so just on the K3, no issues.
>
> Please let me know if you have any questions.
>
> 73, Fred
>
> KD8ZYD
> --
> Thanks,
>
> Fred
>
>