[Elecraft] Data transmission on 30 meters with PX3 problem

[Don Wilhelm]

Gwen,

First of all, a T200-2 is an iron core toroid, not ferrite, and is not 
likely to prevent much RF noise coupling.  Any ferrite core will have an 
FTxxx diameter designation with two digits after the hyphen.

That W3EDP antenna is a strong suspect, as is any off-center fed antenna 
or end fed antenna.  They can produce large amounts of RF in the shack.
Install a GOOD current mode choke near the antenna feedpoint.  One of 
the best is a stack of 4 or 5 FT240-31 with the coax wound for 4 or 5 
turns through the center.  That should be placed close to the antenna 
end of the coax - exception, an end-fed antenna may need to use a part 
of the coax as a counterpoise (which is why a minimum length of coax is 
specified for them) - put the choke that minimum length away from the 
antenna.

73,
Don W3FPR

On 9/1/2018 11:00 PM, Gwen Patton wrote:
> This happens very rarely for me EXCEPT for 30 meters. Then it happens so
> much, it makes data modes (CW, RTTY, PSK) useless. I'm using a wired USB
> keyboard connected to the PX3. If I'm on 30 meters, and I use the ATU to
> match the antenna, transmitting any data mode causes extra, spurious
> characters to be added onto the end of the keyboard input buffer. In some
> circumstances, it starts appending additional messages stored in message
> slots mapped to function keys.
>