In a message dated 5/18/2006 9:29:20 AM Eastern Daylight Time,
Subject: Re: [TowerTalk] The simple Gamma Match?
> Now to the question: HOW DO YOU BUILD A GAMMA CAPACITOR OUT OF ALUMINUM
The simplest method and is pretty reliable is to use a combination of
Aluminum tubing and coaxial cable. Taking into account that typical RG 8 type
is around 27mmf per foot, the procedure is to strip the outer jacket and
shielding leaving the center conductor and dielectric. Using the appropriate
diameter aluminum tubing ( I think 3/8 or 7/16 works) slide the coax into the
tubing. I would liberally coat the cable with silicone grease to unify the
dieletric and prevent moisture intrusion. The depth of insertion determines
capacitance, also provides "tuning" the match. Once the correct length is
trim the calbe, seal the end and clamp the braid to your common point feed.
Careful sealing will make it a reliable capacitor. The silcone gease should
prevent condensation build up. For higher power use larger cable.
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