This is a simple board that switches 4 antennas to a single transceiver. It features SO-239 coax connectors, relays with popular footprints and flyback diodes. Unused antennas are grounded. It can be driven by virtually any controller in the shack.
How to get one?
- the PCB
- 5 x SO-239 connectors: the rectangular, panel-mounted flavor
- 4 x relay with 12V coil: Schrack 6-1393243-3, Relpol RM-84, or similar
- 4 x diode: any will do, for example 1N4001 (but not 1N4148!)
- BS23 enclosure or similar
- random screws and washers
Remote QTH markets a similar switch with the same Schrack relays and says that they can handle up to 2.5 kW.
I recommend starting with soldering down the relays, then mounting the diodes at the bottom side. The diodes can be semi-surface-mounted (see pictures).
Depending on which wiring and controller you have the relays can be operated with a common positive supply (easy to drive with an ULN2003) or a common negative by adjusting which way the diodes are mounted.
Further steps depend on the exact enclosure. A similar assembly can be found here. Usually soldering of the SO-239 center pins must come last.