----- Original Message -----
From: "Andrew Talbot" <[email protected]>
To: <[email protected]>
Sent: Saturday, July 14, 2001 11:16 PM
Subject: LF: Re: re 9kHz NOVs
Rugby at one time in its
history running a few 10s of kW was reckoned to have 500000 Volts on its
antenna.
Sounds a bit high. According to Watt (VLF Radio Engineering, end of chapter
2), Rugby is voltage-limited below about 21 kHz. From the figures he gives
for the post-1958 configuration I estimate the feed current as 500 to 600 A.
If I interpret his graphs correctly, the reactance of the aerial (and
therefore of the resonating helix) is about 200 ohms.
This indicates a maximum voltage on the top hat in the region of 100 to 120
kV. One of Watt's graphs shows a figure of 165 kV as the voltage-limited
figure for the original 8-tower array.
73 de
John Rabson G3PAI
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