In article <[email protected]>,
Dave G3WCB <[email protected]> writes
Dear Pat, Les, LF,
I've been using the Icom PCR-1000 on LF for a few months, and it works
pretty well with my inverted-L antenna. It tunes down to 137 kHz OK so you
don't need a converter, but you do need a pre-amp/preselector to get the
best from the radio and suppress any birdies. I have been using the design
from G3YXM's webpage http://www.wireless.org.uk/circuits2.htm. (The one with
the two Toko coils)
Thanks Dave for that, I should have that same pre-amp in circuit
sometime in the next few days and will be interested to see the
difference with my small loop.
The tuning is very stable and repeatable, the only slight drawback being
that you can't fit any additional narrow CW filters. This is fine for most
LF modes, ARGO etc, but if you need further filtering for audible CW, say,
you can follow it with an audio filter or use a filter program such as
Spectran.
This is my experience with the PCR1000, I was surprised just how stable
it became after allowing it to warm up unlike my IC-725 which has a
permanent drift, not very much but too much for LF listening which is
a pity because I have better filtering in it. I also use a Datong FL3
for audio filtering as and when necessary.
Set the radio to 135.500 kHz USB to view the entire LF band using Spectran.
I do this but found I needed to damp the Q of the loop to see the
full bandwidth, the next loop to be built hopefully will improve on
this.
--
Les G8ARF / G3VYZ / RSARS 173
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