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[TenTec] Re: RX-340 and Noise Reduction

To: <tentec@contesting.com>
Subject: [TenTec] Re: RX-340 and Noise Reduction
From: jimr.reid@verizon.net (Jim Reid)
Date: Sat, 16 Feb 2002 10:49:24 -1000
Hi again,

The subject is the apparent noise from the RX-340.
The solution is to use the radio appropriately,  with
help from the amazing agc system within the 599zx!

Optimum solution appears at hand!!  For the given band
of operation at the moment,  listen in a signal free
band area.  With the 340 "Manual Gain" control (which
is the IF section gain control):  switch your antenna
connection ON and OFF while lowering the gain of the IF.  
You will quickly discern when you have eliminated all noise 
generated from the "hot" circuits components within the 340,  
and are only hearing noise which appears when the antenna 
is connected, and the output is absolutely quiet with the antenna 
swiched OFF (or signeficantly more quiet than with the antenna ON).
Now, with the zx agc active you have essentially absolutely
quiet band conditions,  but you will be able to hear/copy
signals right down to,  and even within the noise floor
or your antenna system!

This morning and on 10 meters I find that I am using a cut
of 65 dB to the IF strip gain!  And hearing/copying everything!

Not participating in the ARRL CW test(nor will I in the SSB
later).  Not that much fun just sitting here doing VE,  Mainland US and 
XE,  hi.  And, I am not a rate "junky".

Someone wondered about the filters in the coming Orion from
Ten Tec.  As the Pegasus,  a $900 rig,  has 34 available DSP
rcv filters, from 300 Hz out to 8 kHz (the 340 has a selection of 
57 filter BW's from 100 Hz on out to 16 kHz, plus another set 
of "Fast Filters" for data modes critical about phase delays),  
I suspect the Orion will similarly have a rich set of DSP filters.
And probably nary a crystal filter.  BTW, the 599zx offers
added filtering on down to only 10 Hz BW,  no idea when
I would use that,  hi!

73,  Jim  KH7M

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