Hi Art,
atrampler@att.net wrote:
I've noticed that with my Omni VI (opt 3) on 40 meters I will clearly hear key
clicks from some stations, with what sound like true keying sidebands when they
are , and keying with a bug or straight key. These clicks or keying sidebands
can be 5 khz away and still S9+, and are not nulled by using the 500hz 9mhz
filter.
There are some stations where I pick this up even if they are using a keyer...
So...question 1: can the use of a straight key or bug produce keying sidebands
or clicks if good solid contact is not being made (as sounds to be the case in
this situation);
Maybe on an older transmitter where the key contacts are directly keying
a stage of the transmitter. With any commercially built transmitter,
since the late 70s I would guess, there are keying control stages in
between the key contacts and the keyed stage of the RF portion of the
transmitter, where the keying actually occurs, that should produce a
repeatable and consistent keying characteristic (good or bad) regardless
of the contact quality of the key or bug.
and
Is the Omni VI especially sensitive to the received CW wave form (perhaps due
to something in its AGC structure)?
I don't think so.
I have listened with AGC fast, slow and off...and these keying sidebands and/or
clicks are still there.
You should try the 20 dB attenuator switch. What you want to know is
whether the apparent keying sidebands are being produced by the other
guy's transmitter and really being radiated, or if they are being
produced in your receiver. Reducing their signal level so they are not
stronger than S9+10 or so
may be necessary to stop some kind of distortion from occurring in your
receiver front end.
So is it me...or just that many crappy signals on 40 meters?
Maybe a bit of both.
DE N6KB
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