I finally found the time to complete the 160m project this past weekend.
Here is what I wound up with:
-115 feet of Rohn 25 base insulated with a commercial system insulator
-8 feet of aluminum mast sticking out of the top.
-123 feet total height.
-30"x30"x30" concrete base.
- Steel guys at the 30,60,90, and 110 foot level each broken up with insulators
at the end of 24 inch long grips away from the tower.
- The guys at the 110 foot level are broken up into 70/60 ft lengths.
- The guys at the 90 foot level are broken up into 60/50 ft lengths.
- The guys at the 60 foot level are about 80 feet long.
-The guys at the 30 foot level are about 60 feet long.
- The Top two guys go to a screw-in guy anchor. The bottom two guys go to
another screw-in anchor.
- 24 1/4wl long radials of 14 gauge insulated THNN copper wire laying on the
ground.
- C shunt network totaling approximately 2,200 pf.
- SWR 1:1 from 1818-1836
- SWR 1.5:1 from 1792-1864
- Lowest R = 29 ohms at 1780.
- Nearest tower is about 60 feet away @ 60 feet with 15m yagis
- Next tower is 80 feet away at 80 feet high with 3x 75m verticals, 2x10m
yagis, and 20m yagi.Electrically , this tower might pose a problem on 160m.
- Total cost for the whole shebang= $2,800.(Those damn grips aren't cheap and
they rip up your hands!)
Hell of alot of work to get it all up, guys broken, radials layed, etc.
but lots of fun nonetheless! I originally tried series C and then series C with
shunt C together with no luck. Shunt C only worked like a champ. Have 4 x 500
pf (5kv)doorknobs mounted on the tower along with a tower mounted Jennings
Vacuum variable 100-300pf 7.5kv all in parallel. The vacuum is at the midpoint
range. A section of copper tubing flattened with a hammer connects the network
to the radial system which is connected to a copper ring around the tower base.
The copper ring and radials are ground isolated at this point. (floating)
Now if I can find the time to get on the air I can see how it will
perform. If you hear me gimme a call! Thanks to everyone who provided insight
and tips. See you all on topband.
73, Ken , N4UK
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