[CQ-Contest] RX Heresy?
tree at kkn.net
Fri Feb 26 08:30:17 PST 2010
I have been using a K3 now since the IARU contest in 2007. I sent it
back into the shop just before the ARRL DX CW contest to get the beta
hardware upgraded to production and ended up operating the ARRL 160 CW
contest with the same radios I used some 30 years ago in contests - a
Drake line with an R4-C receiver (Sherwood mods).
I think there were three main differences:
1. On my JA beverage, there was some kind of noise (sounded like power
line or perhaps some kind of power supply) that the R4C noise blanker
could eliminate if I used the stock first IF filter (aka roofing filter).
However, this meant that any strong signals in the passband of this
filter (+/- 6 kHz or so) would key the noise blanker. This was very
annoying and resulted in me being unable to finish QSOs with several
stations that called in. I am pretty confident that the K3's excellent
noise blanker could have dealt with this noise using much tighter roofing
filters (typically 400 or 500 hz) which would have resulted these QSOs
being made - plus less fatique dealing with the QRM from nearby loud
2. The diversity reception to Europe is a definite improvement over using
just one antenna. I can't say if I would have worked more Europeans if I
had this - but I know it would have been easier than if I did. I had to
switch back and forth between my beverage and transmit antenna often to
see which one was best (my TX antenna is directional as well). Connecting
my brain to the ionosphere is stereo is probably the most significant
improvement I have made at my station since I strung up my beverages.
3. Not having a radio interface was a pain. Normally, I can create a band
map of stations fairly easily (doing dupe checks as I go up the band).
Without the interface - I had to enter frequencies manually, which was a
pain - and also not as accurate.
Having had these things in place might have resulted in a slightly higher
score. If the fatique issue was enough different - I might have operated
longer which could have also improved my score. I took a few hours off
each night to get some sleep.
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