[Elecraft] KX3 digital

Don Wilhelm w3fpr at embarqmail.com
Fri Jan 11 19:25:22 EST 2013


It used to be that 5 watts on PSK31 was all that was needed, most all 
operators were using low power because it worked well.  Most advice was 
to keep the power low - below 20 watts if I recall.   As time went by, 
the power levels used on PSK31 have crept up and many operators are now 
using 100 watts or more.  That kind of power in the narrow bandwidth of 
common PSK wattering holes will take over the AGC in the receiver 
because most are using bandwidths of 2.5 kHz or greater to see the full 
waterfall display.

The AGC will respond to the strongest signal within the filter bandwidth 
and will make weaker stations more difficult to copy. Sometimes turning 
off the AGC will help, but concentrating on the station you wish to copy 
and narrowing the IF filter bandwidth will help even more.  If you only 
want to work one station, there is no need to see the entire PSK31 
band.  Narrow the receiver filter and use the VFO to tune the desired 
station to the center of the IF passband.

73,
Don W3FPR

On 1/11/2013 6:13 PM, Ariel Jacala wrote:
> 5 watts on PSK will work if you are in an empty section on the waterfall.  In a crowded situation with strong signals nearby, you will be stepped on and obliterated by the strong signal.  Certain DX stations are notorious for overdriving the waterfall and wiping out other signals.  You are better off calling CQ in location away from nearby strong signals.  At 5 watts your printing on the waterfall can be faint depending on propagation.  I did get Hawaii once on PSK with my K2.  My luck with PSK has always been better at 25-30 watts.  That is just the nature of this mode.  At QRP power, CW is much more efficient.  Make sure you have enough drive to just trigger the ALC circuit.  You are also better off decoding the PSK signal with Fldigi or DM780 - just a better PSK experience with the macros and all.
>
>



More information about the Elecraft mailing list