I well remember that many years ago there was a photo in either Radcom
or Short Wave Magazine, of an Austin Mini equipped with a rather large
base-loaded Top Band (160M) antenna with the caption " The Mobile
Station of G3???/M Screwed to the Base of his antenna!"
73
On 28/05/15 15:24, John Rabson wrote:
I recall a few years one of the British Telecommunications journals
(POEEJ/BTTJ/IBTE/TCNJ - I forget which name it was using at the time) had an
item about a low-loader mounted LF/VLF station which had a radiator supported
by a helium balloon. Or was it the Navy's definition of mobile: anything you
can move around with a battleship?
John F5VLF
On 28 May 2015, at 00:10, DK7FC <[email protected]> wrote:
Hmm, i find someone should do a real mobile (mobile-mobile, with a velocity >
0) experiment. A 1.5 m long CB antenna with a special preparated feed point should
work. And i think that the wire works better with a fixed C in parallel, even if
this reduces the efficiency. But it stabilises the SWR or better said, the voltage
on the wire. Corona? Where is the problem with corona? :-)
Markus, could you calculate the ERP when 10 kV rms is applied to a 1.5m high
antenna on a car roof? I bet you have all the formulas in your mind :-)
Maybe the antenna has 10 pF. I remember i have a 470pF/16kV capacitor at home.
So if C = 470 pF and f = 475 kHz, L = 239 uH With 470 pF parallel to the
antenna, a moving wire (= changing C) does not make a significant effect i
think.
10 kV at 239 uH at 10 kV is 14A. If P = 200 W, the losses must be 1 Ohm !
With a good RF litz wire, this is possible :-)
What would be the ERP and possible distance?
It would be interesting to try that in WSPR / QRSS-60 :-) I would also drive to
someone for making a CW QSO but most likely there is a LOT of QRM when
driving...
More ideas?
73, Stefan
[email protected]
Researching history of RABSON, BLACKSHAW, GAUNTLETT, VERLANDER and ROBSONNE
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