Message-ID: <003101c8584e$7aa9c960$6901a8c0@AIRPORTTERMINAL>
From: "Jay Rusgrove" <JRusgrove@comcast.net>
To: <rsgb_lf_group@blacksheep.org>
References: <88d2415e0801160551q12905110v3611d374f38a6963@mail.gmail.com>
Date: Wed, 16 Jan 2008 09:45:46 -0500
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Subject: LF: Re: LF Receiver
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Laurie

I've been using the RF-590 for 8 years now as my primary LF/MF receiver with
no problems or complaints. The 1 dB compression and 3rd distortion is on par
with other 'premium' military grade receivers and phase noise rates up there
with the best of the lot. The only negative I've found with this receiver is
filter 'blow by' on extremely strong signals. It's no worse than other
receivers of this type and is caused by limited stop band attenuation of the
mechanical filters. The fix would be to use a tandem set of filters or,
better yet, put a second set of filters just ahead of the detectors. This is
what I've done on homebrew 'contest grade' receivers. But then again...I'm
not using the RF590 for contest work and it has served me well on LF/MF. I
use a GPS referenced 10 MHz standard into the external reference -frequency
accuracy is deadly. Let me know if you have any questions.

Jay W1VD  WD2XNS  WE2XGR/2




----- Original Message -----
From: "lawrence mayhead" <laurie.mayhead@googlemail.com>
To: "rsgb" <rsgb_lf_group@blacksheep.org>
Sent: Wednesday, January 16, 2008 8:51 AM
Subject: LF: LF Receiver


> Many thanks to those who responded to my mail on the subject of receivers
> for LF/QRSS.
> and my problems with my 1792.
> Paul Hendrik for the URL re circuits Tracey Gardner for the e'bay lead,
and
> Warren for suggestions
> re alternative Rx's.
> The lack of AGC OFF on DSP receivers is a worrying trend as Andy says.
> So I have been looking around!
> I have flirted with the possibility of  the Harris 590 or the Collins
2050,
> both have excellent specs and are non DSP, they look good,but do I want to
> take on another servicability problem, and they are not cheap.
> The Ten Tec RX340 also excellent spec. but its DSP and no AGC off.
> The AOR 7030 is non DSP and the spec is good but operationally it is very
> daunting,and it won't tune in 1Hz steps and it BFO offset has only 33
steps.
> I am concerned about setting it up for ARGO etc.Any comments Alan? also I
> guess its coming to the end of its production.
> So that leaves SDR receivers like the Perseus, thanks Johan, but these are
> digital, can the AGC be turned off? and another problem if my computer
sound
> card is tied up  processing  I/Q signals can it  also  do the FFT analysis
?
> at the same time. Perhaps Andy can help?
> So I am still looking
> 73 Laurie.
>