In my early days of SO2R about 8/9 years ago, I used a
rudimentary set up, no filters or stubs, and pretty close
antenna spacing ( don't try this at home kids!). I was using
an FT1000MP and a TS930s/PIEXX. The FT1000MP generated hash
even in key up with PTT operated, whereas the TS930S was
perfect. Only 100w was used at this juncture. These days I
would regard that as unacceptable, but back then, well I
just soldiered on.
I therefore got rid of the MP, and eventually got a pair of
TS870s. By this time both the QTH, and therefore the
antennas had changed ( but still no filters for a while),
but I never experienced wide band phase noise in key up
conditions with the Kenwoods, neither have I done so
latterly with the IC7400 (=746PRO [ but with much better PSU
filtering] in the U.S.), nor with the IC756PROIII, in fact I
would say from other ( dummy load in shack) tests,
categorically that they are quite clean.
So, some do and some don't, and you just have to find out
which are which ;-)
73
Clive
GW3NJW
-----Original Message-----
From: cq-contest-bounces@contesting.com
[mailto:cq-contest-bounces@contesting.com]On Behalf Of David
Hachadorian
Sent: 13 November 2006 16:27
To: cq-contest reflector
Subject: Re: [CQ-Contest] Wideband noise
----- Original Message -----
From: <zl1aih@ihug.co.nz>
To: <cq-contest@contesting.com>
Sent: Monday, November 13, 2006 8:04 AM
Subject: Re: [CQ-Contest] Wideband noise
> Hi All,
> For CQWW CW next week end, I checked an IC-
> 746PRO in a Multi-Single arrangement. Listening
> with an IC-781, the 746 generated severe wideband
> noise during key-up condition.
> Reversing the rigs, the 781 was undetectable other
> than on the harmonic freqs.
I don't know about the 746pro, but wideband noise on
transmit, keyed up or keyed down, is a typical
characteristic of synthesized radios. Wideband noise
reduction is the primary reason for having a bandpass filter
on all radios in a multi-radio setup, unless the antennas
are very far apart. I'm surprised that you didn't hear noise
from the ic-781.
Dave Hachadorian, K6LL
Yuma, AZ
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