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From: "Dave G3WCB" <ganymede444@btopenworld.com>
To: <rsgb_lf_group@blacksheep.org>
Date: Sun, 9 Sep 2007 12:49:11 +0100
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Subject: LF: [500] Best receivers?
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Status: O

I use my trusty Icom IC-PCR1000 on both 137 and 500 kHz. It's extremely
stable, has a 1-Hz tuning step and as it is very small, it can be tucked
away on a shelf or under the desk in the shack. Doesn't even look like a
wireless..

It definitely needs a tuned pre-amp for 137 kHz, although I can get away
without one for 500 kHz. The down side is that it ties up a PC (which can be
a QRM generator in its own right), and there is only one IF filter bandwidth
awailable, which is a bit wide (3 kHz.) Not a problem for digimodes, but too
wide for CW on a busy band.

For other work, I use a W&G SPM-30, with IF bandwidths of 3100, 1740 and 24
Hz. As you probably know, this is a serious bit of test kit, but it has it's
own internal batteries so that you can lug it across fields, through hedges,
etc, while making remote field-strength measurements.

I have just completed a simple direct conversion RX for 500 kHz, and it
works surprisingly well. It uses a MC1496 double balanced mixer and an audio
amplifier with a switchable 1000 Hz audio filter (88mH toroid). The LO is a
1 Mhz Murata ceramic resonator, pulled with a variable capacitor and then
divided down to cover 500 - 505 kHz.

The audio "image" can be a nuisance, but I managed to receive John GM4SLV on
it the other evening, so it can't be too deaf.

Details available for anyone who is interested.

73, Dave G3WCB IO91RM

-----Original Message-----
From: owner-rsgb_lf_group@blacksheep.org
[mailto:owner-rsgb_lf_group@blacksheep.org]On Behalf Of Mike Dennison
Sent: 08 September 2007 17:55
To: rsgb_lf_group@blacksheep.org
Subject: LF: [500] Best receivers?


Thanks to those who have so far provided input for the new edition of
LF Today.

My next question is what are people's favourite receivers for use at
500kHz?

My IC-706 seems adequate, but my TS-850 is deaf due to the
attentuator switched in to prevent overload in the MW broadcast band.
So what is your experience?

Thanks in advance for any data.

de Mike, G3XDV
============