mast height: 60mtr (200ft)
the tower sections have an 80mm face, but the leg diameters reduce.
The lower sections use 50mm solid bar and reduce gradually to 37mm
diameter on the upper sections) Total weight of the tower is 6000kg.
Each of the guy ring assemblies weights 200kg
mast is designed to be self supporting. This means that the mast
could have been assembled on the ground and then lifted into
position. For economic reasons the first half of the mast was lifted
into position by local crane operator and the final half of the mast
was lifted into position by a large 200' crane brought in from
4 five element 20metre band mono-band yagi antennas 44ft booms
switching: Each antenna can be switched in separately or all four
can be feed in phase.
motor: 240VAC, single phase 3/4 Horse with a double worm gear box.
mast can rotate 360 degrees in about a minute.
guys are 14mm diameter Kevlar with a polyester jacket to provide UV
protection. Breaking load is 8000kg with low stretch.
line and phasing harness are 1/2" heliax
antennas were designed for optimum performance using EZNEC Pro
Array gain is 20dBi @ 6.1 degrees. The vertical beam width is
7 degrees with -3dB points of 3degrees and 10 degrees.
switched with vacuum relays
As I say, Ian works
fast and the last report I got was that as of Monday (11/06/2007) it
is all connected and seems to performing well with good VSWR for all
I found this comment
amateur radio newsgroup: uk.radio.amateur
who's every heard Ian, VK3MO on 14MHz ssb, using 1 watt to his
beams knows that output power is not everything.
he's usually S9 on whatever power he's using... the answer lies in
the antenna., as we all know.
system is a truly impressive engineering achievement.