Modifying coax connectors
Custom N-Adapter for the Amplifier Build Yesterday during the amplifier build, I needed a coax adapter – an N male to N female – but a bit longer than usual, to connect the amplifier output from the directional coupler to the T/R board. It turned out I hadn’t paid attention to the minimum bend radius of the coax, so I had to get creative. At first, I planned to just order an adapter, but I couldn’t find exactly what I needed. Instead, I decided to modify some existing connectors. Interestingly, the backshell thread on many clamp-type N connectors is the same as the retaining ring thread – 5/8"-24 TPI – meaning you can actually thread a female connector into the back of a male RG213 clamp connector. Unfortunately, that combination would have been too long. I own an early 1940’s Blomqvist lathe, a close copy of the famous South Bend 9". It’s fully equipped with all the gears for cutting threads, so my solution was to set up for 24 TPI and cut the thread directly onto the...