Making
a Feed I Can Live With
a.k.a. Making a silk purse from a sow's ear
Cushcraft, for some reason - likely marketing - presents the gain of their antennas in dBi, not dBd as most do. That makes it look like they have an the same gain as a longer boom, but subtract 2.15 dB from the dBi and you have a number to match with the rest of the pack.
When I opened the carton to inspect the first antenna for shipping damage I checked out the feed point Cushcraft provided and was much less than impressed. The "user interface" turns out to be a cheap SO239 made of aluminum with a clear plastic insulator. With this (maybe) 29 cent connector it was obvious that it's mechanical ability under these conditions was going to stretched. I tossed it on the bench and set out to make a new feedpoint with N connectors.
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The "El Cheapo" SO239 on the left. Notice the radial crack, visible at the 8 o'clock position The business end of an Amphenol UG58A/U panel mount N Type connector. |
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This
new feedpoint uses a copper stud from the transistor. This is easier
to solder than stainless steel and the flat tab rests neatly in the center pin
of the N connector stub.
The Teflon from the standoff was removed, drilled out and offers mechanical stability to the soldered connection. |
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Which
connector do you want?
You could also use an Amphenol UHF panel mount if you're using RG8 style coax. |
Finished
and ready to go!
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With this new feed point I can chuck the N to UHF adaptors and mate the N connectors of my harness directly. N connectors are much more water resistant too, plus the new feedpoint offer a much better seal than the El Cheapo one supplied making prep of the match much easier. |
22-Sep-2014