Because I was concerned about missing short calls, I've constructed a simple
circuit that feeds wideband audio to my left ear and narrowband audio to my
right ear. It has a balance control for adjusting the relative audio
levels, and if I desire, I can select both ears in either narrow band or
wideband mode. Regarding the tuning technique, with the FT-1000D it is done
with the clarifier on the receiver first by moving just a bit up and down
and then widening the sweep eventually going up and down about 500 Hz. This
has the effect of increasing the probability that the short calls will be
copied, since it is more probable for them to be close to my transmit
frequency. I use TR log setup to automatically reset the clarifier after a
CQ call. If, on the rare occasion, I don't want it to be reset, then I have
a special function key set up for CQ without clarifier reset. I'm able to
pick out extremely weak signals that are not detectable with just the
receiver's 250 Hz IF filter. These techniques work, as witnessed by many
plaques on the wall (many 1st placeWorld 1.8 MHz in CQWW), 40 Zone WAZ, and
the most difficult award from the Middle East: 160M WAS (May 1997). I don't
know about using the auxilliary receiver in the FT-1000D. It may be OK for
general work on HF, but as far as serious weak signal work in a crowded
band, it is missing a lot (not like the excellent main receiver).
73,
Riki, 4X4NJ
----- Original Message -----
From: "Bill Tippett" <btippett@alum.mit.edu>
To: <topband@contesting.com>
Sent: Saturday, July 19, 2003 2:32 PM
Subject: Topband: Re: Weak Signal Reception (EME view)
> 4X4NJ wrote:
>
> Regarding not hearing stations calling off frequency, this can be a
problem
> when using such narrowband reception, and especially in contests, it is
> necessary to always "wiggle" the dial back and forth after each QSO to
pick
> up stations that may be calling off frequency.
>
> Believe me, you will waste a lot of time tuning a 90 Hz
> filter + and -500 Hz from your TX frequency, and you will likely
> miss many guys who call once and quickly move on. It's been my
> experience that I miss more callers using narrow filters than
> using a fairly wide filter (.5 to 1 kHz) and "brain DSP". Switching
> RX antennas further complicates things because you need to do that
> quickly as well, to catch the faster one-call guys. Maybe you
> don't have to worry about this since everyone will wait for you
> (to get your 4X4 multiplier), so it may be different in your case.
>
> BTW, I also use the MP Main VFO for RX and Sub for TX as K6SE
> described. Too bad Yaesu won't make a firmware mod to fix the TX
> frequency so you could use BOTH Main and Sub for simultaneous RX...
> e.g. setting one to UCW and another to LCW would allow you to
> use narrower filters on each passband and listen simultaneously
> to both sides of your TX frequency. I've suggested that several
> times but their response is the same as for clicks (i.e. nil).
>
> Everyone has their own opinions about such things and that's
> what makes a contest such a good test of what works and what doesn't.
> The best way to improve our results is for all of us to try different
> things and see what works best in our individual case.
>
> 73, Bill W4ZV
>
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