Hello All,
Was interested in the comments re the M.T.V. Some years
ago
came across a reference in Technical Topics, RSGB. Unfortunately
didn't
note which issue or which manual .
Did manage to find some data in AMATEUR RADIO VERTICAL
ANTENNA Handbook by Paul H. LEE. 1974... CQ Technical
Series.
Two types discussed.
A. NORD Antenna...... for 50 to 150 kc/s/...
Has a centre metal pole with a gamma type matching wire from the top
of the
centre pole. (No detail of the spacing, wire dia or centre pole dia.
except that the bottom of centre pole is earthed. From the top of the
centre pole there are three sloping wires out to three perimeter poles
each of which is earthed through a variable condenser. The three
perimeter pole earths are connected back to the earth ing point of the
centre pole.
Dimensions give by LEE for 50 to 150 kc/s..
Centre pole ( or tower !!) 450 feet.
Perimeter towers 150 feet
Spacing from centre pole to perimeter poles 500 feet.
B. Data for 2 to 4 mc/s...
Centre pole 30 feet high
Perimeter poles 10 feet high
Spacing centre pole to perimeter poles 33 feet.
and the total capacity of the three variable condensers , C1 + C2 +
C3 is
equal to 1500 mmfd.
The UG Tyupe Vertical...
First Model.... Design for 2 mc/s..
Horizontal wire is 52 foot long.
Three down wires, with centre down lead connected to the mid
point of
the horizontal wire, ( i.e. at the 26 foot point, and the others
, one each side
at the 25 foot and the 27 foot points..)
At the bottom , one of the out side verticals is earthed. The centre wire
is connected
to the earth point of the earthed vertical through a variable
condenser to the earth stake to which the earthed vertical is connected.
The other outside vertical comes down to just above ground
level
and is connected to the feedline system. The length of the verticals
is 25 feet
for each one..
Second design.
Top horizontal wire is 52 foot long supported at the 25 foot
level ( above
ground ) .
The three 25 foot vertivals are attached as follows.
First vertical is attached to one end of the horizontal wire and drops
down to become the feed element.
The second vertical drops down to become the earthed vertical,... one
foot away
from the feed vertical.
the third vertical drops down from the 2 foot point ( from the
end of the horizontal wire ) to connect to a variable condenser
the other side of which
connects to the earthing stake of the centre vertical.
As it is quite a few years ago since I made these notes I can not remember
if there was any other data.
Perhaps a search of the www pages for the NORD or UG Type
vertical
might bring forth more details.
73 Stan, ZL4MB DUNEDIN NEW ZEALAND.. 23 August
1999
nnnnnnnnn
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