Get a Rohn catalog. It has a diagram for the base of a bracketed tower. The base is 2x2x4 feet. Place 4 feet and a few inches of tower section into the base (about 2-4" should stick out the bottom an
Uh, this is not correct on many levels. First of all, although Cessna ceased production of piston-powered aircraft in 1986, Piper aircraft continued to produce them. Or, at least they tried. Many oth
I once made a helically wound vertical for 40m by taking a half-wave of wire and winding it on a 2x4. Matching was accomplished by tapping the first dozen or so turns and using a seriles capacitor. I
I have a similar situation, and have been able to get my shunt-fed tower to work effectively on both 80m and 160m. My tower is 44 feet of Rohn 25, topped with nearly 6 feet of mast to a Cushcraft A3S
An omega match has limited matching range. If your shunt isn't close to that range, you won't be able to tune it. W8JI has an article about this on his site: http://www.w8ji.com/omega_and_gama_matchi
They do NOW, but they didn't produce them for quite a few years. Cessna did not produce ANY piston-powered aircraft from 1987-1996. Bill Coleman, AA4LR, PP-ASEL Mail: aa4lr@arrl.net Quote: "Not withi
Perhaps part of the solution is to run less SOUP! ( hi hi ) Bill Coleman, AA4LR, PP-ASEL Mail: aa4lr@arrl.net Quote: "Not within a thousand years will man ever fly!" -- Wilbur Wright, 1901 __________
Yes. Bill Coleman, AA4LR, PP-ASEL Mail: aa4lr@arrl.net Quote: "Not within a thousand years will man ever fly!" -- Wilbur Wright, 1901 _______________________________________________ _________________
1/4 wave radials for 40m are 1/2 wave on 20m. If we're talking about a ground-mounted vertical, certainly the 40m radials will work great for 20m. Just put down a lot of them (strive for 20-40 radial
As ouchy as both these might be, it's still better than the big ouch at the bottom of the tower. I ALWAYS do this. I always have a spotter who watches my climb and can call 911 if I do something stup
How broad are these stubs? Wouldn't a 1/4 wave stub tuned for 7.1 MHz only pass 15m at 21.3 MHz? Can they practically pass/reject the whole band? Bill Coleman, AA4LR, PP-ASEL Mail: aa4lr@arrl.net Quo
I don't think that 4 or 5 20 foot radials are going to be a terribly effective groundplane for a 160m vertical.... Even if you bury them. True, the far ends of the wire do less and less "work" of a g
HB25A, HB25B and HB25C. These are pretty sturdy brackets, although they all have some lateral "give". They are for 15", 24" and 36", respectively. My house has 17" eaves, plus gutters, so I had to us
Horizontal antennas, like dipoles, make great antennas, but they are affected by proximity to the ground. They have to be at least 1/4 wave above ground before the radiation pattern is anything but s
Those figures seem big, but this is less than 1/2 wavelength high. It's like putting a 10m monobander at 15 feet! I've never heard of anyone with a 160m yagi at 500 feet. There's a couple of guys who
Are these radials ground-mounted or elevated? If they are groundmounted, don't try to cut the radials to any particular length for each band. Just put down 24 radials the same length as you would cut
To make sure I have my facts straight, I've gone and modeled a 20m long dipole at heights of 10m, 20m and 30m at a frequency of 3.6 MHz (which is darn close to resonance at low heights). At 10m high,
If you look at the whole pattern, the gain lobe is straight up. It looks like a snow cone. This description should be obvious to anyone who has done any modelling at all. If you want to receive signa
Yup. Works great. Noalox is zinc particles in silicone grease, and the tower is plated with zinc. Very compatible. Bill Coleman, AA4LR, PP-ASEL Mail: aa4lr@arrl.net Quote: "Not within a thousand year
I've used ordinary 4-conductor bell wire with about a 100 foot run to control an AR22. Note that the AR22 doesn't have a brake solenoid, which is the largest current draw in the HAM rotators. You mig