[Premium-Rx] Premium-Rx Digest, Vol 86, Issue 1

[Michael O'Beirne]

Dan,

I suspect the problem is not that different from the very high QRM 
encountered in the recent desert campaigns and caused by the very high 
static levels.  You may recall in the First Iraq campaign that US Forces had 
to dig out their old Collins R390As to cope.

I also suspect the answer in part is to add a decent tunable preselector to 
the input to reduce the broadband noise, and also to fit a better mains 
power filter.

I recall being told by a professional communicator at Air Traffic Control at 
a major UK computer centre that they used an old Eddystone EC958 to monitor 
some of the Atlantic HF channels.  They replaced it with a modern receiver 
with a wide open F/E and it was hopeless, probably smothered by the vast 
local QRM generated by the computers.  The 958 in contrast hasd three very 
sharp tuned circuits before the mixer and was able to cope better.

73s
Michael
G8MOB

----- Original Message ----- 
From: "Dan Robinson" <dxace1 at gmail.com>
To: <premium-rx at mailman.qth.net>
Sent: Wednesday, January 01, 2014 2:54 PM
Subject: Re: [Premium-Rx] Premium-Rx Digest, Vol 86, Issue 1


>I have had my 340 for three years now -- it's obviously among
> the top of the pile when it comes to receivers.  But one thing I
> have noticed is that it does not hold up well in noisy receiving
> locations, likely due to its construction in comparison with the
> older boatanchor weight receivers.  Comparisons with my 8718A/MFP
> at my house, which frustratingly has been plagued by a lot of power
> and DSL noise, show that 8718A, which is built like an Abrams tank,
> manages to rescue signals better than the 340 on days when local
> noise is high.