NC Scout at American Partisan has a nice, short article on radio cable/antenna connectors and what is useful for improvising antennas — RTO’s Guide to Connectors.
One of the common questions I get before, during and after the RTO Course is “how in the heck do you remember all those different connectors?” Well, the answer is nothing more than repetition- I know them because I’m built so many antennas over the years and needed the various connectors you come to know what they’re called.
Its a good idea to have a large number of spare connectors and adapters on hand. If you’re making external antennas for your equipment, they’re an absolute must have item. And unlike pretty much everything else we make our antennas from in the RTO Course, they’re the hardest to source in a working environment, so knowing what they are and having a bunch on hand now makes too much sense.
Cobra Heads make improvised antennas fast and simple.
The Cobra Head
A story I tell in class is exactly how I discovered the real name for what I always knew as a Cobra Head. The Split Post BNC Adapter, or BNC Banana Jack Adapter, is widely known to Army guys as Cobra Heads- in fact, I never knew they were called anything else and couldn’t find them for a long time after I got out. I found them at a Hamfest in a big tray of connectors and felt like an idiot when I was told what they’re really called. It didn’t matter- I found them.
Why they’re important is that its the easiest connector to use when building improvised wire antennas. We were given them by the bagful in the Army to practice antenna building, and I came to really appreciate it. Simply cut your wire, match the radiating wire to the red end and ground side to the black, loop it around and you’re good to go. If you want to get the most secure with it be sure to use some ring terminals to connect the wire to the connector. Attaching BNC coax can’t be easier and more secure…