Message-ID: <11994.200003211448@gemini>
From: "James Moritz" <j.r.moritz@herts.ac.uk>
Organization: University of Hertfordshire
To: rsgb_lf_group@blacksheep.org
Date: Tue, 21 Mar 2000 14:49:16 +0000
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Subject: LF: 73kHz Cross-band
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Dear LF Group,
	Sent CQ calls on 73kHz from about 1910 to about 2250 last 
night; saw signals from G3LDO and G4GVC while monitoring 
73kHz, but no replies on 136kHz - only signal seen was DFCW 
from G3AQC. The level of QRN seemed quite high.

I think the idea of having seperate frequencies for each station on 
the band is a good one - I would go along with G3LDO about 
'channel spacing' - maintaining my VFO to within +/-5Hz is fairly 
easy, which would be OK for 10Hz spacing, but not for 5Hz. I will 
allocate myself 71.81 for the time being, unless there is any 
reason to avoid this frequency?

As far as switching antennas goes, I am using a seperate antenna 
for receive when working cross-band - this avoids problems with 
high-voltage switching. The RX antenna is a vertical of about 5m 
fixed to the side of the house, tuned with a small pot core inductor 
and variable capacitor. At the moment it is switched out by a relay 
on transmit, but I plan to add some additional high pass filtering so I 
can monitor 136 continuously while transmitting on 73. The 
seperate antenna seems more prone to picking up mains noise, but 
most of the time the noise floor seems to be QRN or Loran 
sidebands.

I probably won't be available tonight, but should be QRV tomorrow 
morning for cross - band QSO's.

Cheers, Jim Moritz
73 de M0BMU