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Old 02-03-2008, 06:25 PM
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KC4UMO KC4UMO is offline
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Now for the gamma match.
What I used was a piece of element from a TV antenna.
This is 3/8 of an inch. Cut 2 pieces 3 3/4 long. Now grab a piece of RG-8 about 8 inches long and remove the outer cover. Remove braid.
Mark end about 3/8. Then from that mark measure 2 3/4.
Cut material so the 3/8 of the center conductor is exposed.
Slide the coax into the 3 3/4 tube. You now have a 70 cm gamma.

Shorting bar.
You now need an aluminum strip about 1/2 inch wide by 3 1/2 inch long.
Cant find any? I used an old aluminum yard stick.
You will have to fabricate this so that it will go around both the element and the gamma tube. Plus enough to put two bolts in. The spacing from element center top gamma center should be 1 3/4 inch.

You will also need a piece to hold the connector. I used a S)-239 for the time being but this should be a N-type connector.
I will change these out later after testing.

Sorry about the last pic of the shorting bar. I must had sneezed when taking that one.
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