My 6:1 remote antenna switch enclosure turned out well. It’s made from plastic with metallic spray for shielding.
Here’s how you can easily mount a Chinese remote coax switch, using BNC or SO-239 connectors. As I described previously, these units are cheap and have decent specification, but you need to add your own connectors and enclosure. My approach uses 3D printing.
First, measure and design a top plate to hold the connectors. You need to make sure that the connector center pins line up with the circuit board. I used some spacers between the PCB and the top plate to get the dimensions right. Each of the six connectors also has a LED indicator requiring a hole for visibility, as shown above.
Shielding is important. The inside layer of this remote antenna switch enclosure is covered with MG Chemicals Super Shield Nickel Conductive Coating. Two coats provides 40-60 dB shielding attenuation. Of course, you will get better results if you make your own aluminum box, but I don’t have the tools for that.
Make sure you use star lock washers on the connectors to hold them tight permanently. You don’t want to disassemble for repair later on. It’s possible, but a lot of work.
You need a tight fit between the top plate and lower box to ensure shield continuity. You can do this with screws and clamps. There are various ways to get a snug fit The screw on the lower right provides a connection for external ground to the box.
Remote Antenna Switch Enclosure – DC Passthrough Filtering
On the lower left you can see five solder connections. My inner connection is for ground, while the remaining four are 12 volts for relay switching. I am only using four of the relays, rather than six, but that’s easy to change.
My friend Jim VE6JF showed me how to make ferrite bead capacitor filters for the control lines. These include an FB-43-101 ferrite bead, and 500 nF capacitors between the control lines and ground. Again, 3D printing to the rescue, as shown above.
Once assembled, everything works fine.