Name                  Theo Bemelmans
QTH                     Ellikom
Grid                      JO21SD
Licensed            1983
Profession         Technical Advisor (in a big technical school)
Station Info         Ten-Tec Orion, home made amplifier using 4-1000B tube

4-Square Info
Band - 80m
Operational since July 2008.  Full size, tilt over quarter wave verticals, last 12m Spiderbeam poles, free standing.  Approximately 200 radials at the moment and planning more.

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1.     Tilt over section ready for concrete pouring in the base.  The tilt over point is 1.2m high.
2.     The first 8m of one vertical, isolated from the base.  It is easy to tilt by one man because of some counterbalance weight at the bottom.  Planning to put a small winch on each so it can even be done by a child!
3.     The complete quarter wave vertical with the 12m Spiderbeam pole on top.
4.     Some of the 200 radials on the grass, most of them are now invisible.

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5.     Some more radials!
6.     The finished tuning stub (K9NS for info in detail).  Planning some relay boxes for switching to CW at a later date.
7.     Home brew hybrid coupler (like Comtek) that was used in the past on the wire 4-Square hanging from the tower.
8.     The variable Lewallen network that was built in winter 2008/9 that is in use now.  Planning to alter the phasing to 112 and 225 in the future.  Using vacuum relays and rigid coax for internal wiring.

9.     10.     11.     12.

9.      Fluke PM3392A digital, 4 channel scope and PM5314 Function Generator for all the measurements in the field.
10.    Shows the -90 degree phase shift on the diagonal elements.
11.    Shows the -180 degree phase shift made with the half wavelength coax line.
12.    Shows the -90 degree phase shift between the side elements.

13.     14.

13.     Shows the total firing through the diagonals.
14.     The view of the finished 4-Square, in the middle is the 30m tower with 2 ele HB9CV for 17m, 5 ele yagi for 20m, 3 ele wire yagi for 30m, 4 ele yagi for 40m and 160m antenna down beside the tower.  All the antennas are home brew and full size monobanders.

More information about Theo's antennas and more pics of his 4-Square are on his web site at

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