[Elecraft] P3 Transmit Display Failure

[Alan Bloom]

My first thought is there might be an intermittent RS-232 connection 
between the K3 and the P3.  That would prevent the P3 receiving the TX 
and RX commands from the K3 so that the P3 gets hung up in TX or RX 
mode.  If you can lay your hands on a spare RS-232 cable, I would try it 
to see if that fixes the problem.

If the RS-232 connection is confirmed OK and the problem still occurs, then:

Have you tried cycling power without restoring the config file?  If it 
really does require the config file restoration to restore proper 
operation then it must be some setting that is accidentally getting 
changed.  That can sometimes be caused by some computer software sending 
commands to the P3 via RS-232.  Try running the K3/P3 with no RS-232 
connection to the computer and see if you still see the problem.

If the problem occurs with no connection between the K3/P3 and the 
computer and you can confirm that it does require a config restore to 
get back to normal operation, then it sounds like the EEPROM in the P3 
must be going bad.  I have never heard of that happening, but I guess 
it's possible.

Alan N1AL


On 11/18/2020 12:19 PM, hawley, charles j jr wrote:
> I have a reoccurring issue with the P3 display of the transmit cw display. Occasionally, the P3 doesn't display the TX waveform ( I have never noticed if this happening on SSB...probably not since I have never had to fix it). The fix is loading a config file stored when the problem was not happening.
> I have tried to store a config file when it was happening just to see and then restore using that file. What happens then is the P3 display locked up with a dit and could not be unlocked.
> After this test, I had to turn off the K3s and unpower the P3, restore power and turn the K3s on, and restore with a copy of the config which was taken when the display was showing transmit cw.
> I'm thinking stray RF somehow causing this but never happened on SSB...and I have no clue what is getting flipped in the rig or P3 to have this happen.
> Since I can restore the config and fix it, I guess I'm mostly curious why it's happening, any ideas?
>
> Chuck Hawley
>   c-hawley at illinois.edu
>
>   Amateur Radio, KE9UW
>   aka Jack, BMW Motorcycles
>