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Remote Coax Switch

Can one ever have enough antennas? The answer to this question is no, no one can not. This is the first law of HAM radio; More antennas = more better. But with more antennas comes more coaxial cable, and with more coax comes additional holes in the side of the house. This may be problematic for those who’s actions are scrutinized by others at the residence. One way to get around this problem is to have a remote switch at the antenna side of the coax. This way one can just switch to the antenna one would like to operate.

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This can be achieved a couple different ways. One way is to use a remote relay driven switch where a DC voltage offset into the coaxial cable and then removed at the switch box before it makes it to the antenna. This option is nice because a separate control cable is not required to be run, but is usually limited to just a two position switch. If a control cable is run, a multiple relay controlled remote switch can be used, allowing for many more connections. If we recall the first law of HAM radio, this second choice is going to be the better one.

2022-01-14-12-57-43-QRZSo, what’s the best way to go about making this happen? Well there are pre-built solutions out there, and Ebay is a good place to look for those. There are also some kits, and a decent used market, if you get lucky with your timing. The option I decided to go with was a four position remote relay switch that came with an optional housing. I decided to go with the housing, and figure out the switch myself. All the switch must do is feed 12 volts to a particular relay in order to activate it. A simple selector switch for low voltage DC should do the job.

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For ease of connection and disconnection, we can make a simple printed circuit board that a selector switch can be soldered to. This way we can make a more modular design using screw terminals and a barrel jack. LEDs can also be added to indicate which position the switch is in. Now that we have a remote switch, more antennas can be added and we can also test out antennas without having to go switch them out right away if they don’t live up to expectations.

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