I'm building an antenna I can hide in an approximately 40' tall Blue spruce tree. The intent is to snake 40' of 1/2" CPVC pipe up the trunk, with the coaxial antenna inside it. These trees aren't made for climbing since they have hundreds of dead sticks inside, so tossing a rope over a branch and pulling it up isn't in the plan. Here's an article on the basic antenna. http://www.iw5edi.com/ham-radio/3777/the-vertical-bazooka-antenna?the-vertical-bazooka-antenna,18
Here are the formulas;
The coax is RG/8x-95
Center conductor Lcm =7500/freq
7500/27.3 =274.7cm =108.15"
Braid folded back over coax
Lbcm =7500/27.3 X VF (Velocity factor of the coax)
274.7cm X .8= 219.76cm = 86.5" . I'm using VF =.8 because it was in the middle of all the values I found on the know-it-all Internet.
I trimmed the coax 'outside covering layer" by very carefully scoring it with a knife lengthwise. Don't get as deep as the braid. You can then split at the cut and strip it down as far as you scored it. Take your time. Don't nick the braid. I suppose there's a tool for that.
I'll keep you posted on my progress.
Here are the formulas;
The coax is RG/8x-95
Center conductor Lcm =7500/freq
7500/27.3 =274.7cm =108.15"
Braid folded back over coax
Lbcm =7500/27.3 X VF (Velocity factor of the coax)
274.7cm X .8= 219.76cm = 86.5" . I'm using VF =.8 because it was in the middle of all the values I found on the know-it-all Internet.
I trimmed the coax 'outside covering layer" by very carefully scoring it with a knife lengthwise. Don't get as deep as the braid. You can then split at the cut and strip it down as far as you scored it. Take your time. Don't nick the braid. I suppose there's a tool for that.
I'll keep you posted on my progress.