From: "Mike Dennison" <mike.dennison@rsgb.org.uk>
Organization: Radio Society of Great Britain
To: rsgb_lf_group@blacksheep.org
Date: Mon, 28 Jun 1999 10:04:00 +0100
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Subject: LF: Spacer
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Since the radio was so noisy this weekend, I spent time both 
improving the transmitted power and getting a better idea of the real 
antenna current.

I finally managed to get 1.7A into my inverted-L from my 200W Tx 
to give 135mW ERP.

Several stations have commented on the strength of the key-up 
'spacer' signal from my Tx (yes, I will fix it). Since my current meter 
does not read at all when the key is up, it took some time for me to 
come up with a measured power level of the leak-through. I found it 
was 3W, which gave an antenna current of 210mA, and an ERP of 
2mW. (Incidentally, when I first started on 136kHz, my current was 
not much more than this and the antenna was smaller!).

Two UK stations have heard this signal and Rik, ON7YD, can just 
read it on his Spectrogram screen. At 176,500km/watt is this a 
record?!!! It certainly shows what can be done with an extremely 
low ERP.

Mike, G3XDV (IO91VT)
http://www.dennison.demon.co.uk/activity.htm