Although my experience with my new PRO2 is limited to a few weeks, its
front-end performance compared with the original PRO has been greatly
improved. I cannot recall ever having to use attenuation with the PRO
although I normally used Preamp 1 most of the time. With the PRO2, I
have yet to use the Preamp or attenuator. The PRO2 front-end is really
that much better than that of the PRO. My experience with the original
PRO dates back to September 2000.
I can copy an S2 CW signal less than 100 Hz from an S9+30 dB signal
using a 100 Hz filter setting. There is no evidence of desensing or
cross-modulation from strong signals on the band. I think that Icom
has figured out how to make near bullet-proof front-ends and with
their licensing of the Rohde and Schwartz front-end technology, things
can only get better.
I agree with the original comment that a 2002 radio should not require
manual attenuation to prevent overloading, and my experience is that
the PRO series does not. On the other hand, the Jupiter is a
considerably less expensive radio and should not be expected to have
the front-end performance of more expensive receivers. Only the
Elecraft K2 seems to be able to pull that off! <:}
73/72, George
Amateur Radio W5YR - the Yellow Rose of Texas
In the 57th year and it just keeps getting better!
Fairview, TX 30 mi NE of Dallas in Collin county EM13qe
K2 #489 IC-765 #2349 IC-756 PRO #2121 IC-756 PRO2 #3235
----- Original Message -----
From: <n4lq@iglou.com>
To: "Frank Mayer" <domino@worldlynx.net>; <tentec@contesting.com>
Sent: Friday, December 27, 2002 6:48 AM
Subject: Re: [TenTec] Jupiter Audio
> I've seen similar post about the IC-756 pro being overdriven by
strong
> signals. The general cure seems to be the same, reduce the signal
level
> by turning off the pre-amp or adding attenuation or reducing the RF
gain.
> The problem seems to be due to the analog to digital converter not
being
> able to handle such strong signals and the common spin these days is
that
> adding selectivity ahead of the DSP is too expensive. It does seem
the
> the new breed of DSP radios requires more use of the attenuation and
gain
> controls that we used to ignore. N4LQ
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