Total posts : 45366
I assume that you are referencing the Ramsey early model FM25 FM transmitter. I have one here and it works verys well. Last question first, I don’t think shielding tape is worth the effort unless you are thinking about lining the entire plastic box and even so I wouldn’t bother. I mounted mine in a metal box which I obtained from junk surplus but any metal box you can find which fits will be a great improvement over the plastic case which came with the unit.
First question second, for the RF output just get a BNC bulkhead female connector for the antenna and connect it to the circuit board with short wires. Works great here. I definitely recommend junking the RCA antenna connectors and BNC or F connectors are the way to go. You might find one which is PC mount which will fit but if not then short jumpers to anything available will work well. For the audio, the RCAs work OK here but the most reliable audio connectors I have ever used are the 1/4 inch phone plugs and jacks made by Switchcraft. The Cannon AC3 series are also excellent but harder to find and more $ than the 1/4 phone equipment.