My Ameritron RCS-4 Remote Coax Switch box failed after 10+ years. The Console switch settings 1, 2, and 3 resulted in high SWR while switch setting 4 did not. Before coming to conclusions that the RCS-4 was at fault, I disconnected the coax feed to the Remote Switch box and connected it using a dual female Barrel coax connector to connect both antennas, one at a time, to the shack’s coax feed. Each antenna was tested and found to have low SWR.

I disconnected the Console from the Remote Switch box and measured each switch position’s AC and DC voltages at the output of the Console. The Console function is to switch AC and DC voltages to the Remote Switch box.

Position 1 = 12VAC

Position 2 = -16VDC

Position 3 = +16VDC

Position 4 = 0VAC/0VDC.

The voltage measurements clearly indicated the Console was working as it should. This left the Remote Switch box as the source of high SWR, most likely due to relay contact failure. I removed the cover on the Remote Switch box. None of the components showed signs of overheating. I could have spent $169.95 for a new RCS-4 but decided instead to rebuild the Remote Switch box. Ameritron’s RCS-4 webpage listed every part in the RCS-4 system so a call to Ameritron was made and all the required parts to rebuild the Remote Switch box were ordered.

Removing the PC board required heating the SO-239 connections on the PC board which was not easy with the PC board still attached to the base plate. This required drilling out the rivets holding each SO-239 to the base plate. I was then able to remove the 5 SO-239 from the base plate allowing me to heat the SO-239s and gently twist/rock the connectors off the PC board.

I tried removing the old relays from the PC board but the relay pin holes were too small and plated through so I used the new PC board I ordered. I rebuilt the PC board with all new components and installed the 4 jumper wires. The base plate was rusty so sanding was necessary to remove the rust. I made decals to replace the original name and antenna labels. The rebuilt PC board was then mounted to and secure to the base plate with new mounting hardware. Successful test of the Remote Switch box was done. The Remote Switch box was mounted to the ground rod outside the shack and the antennas were connected. Test with antennas resulted in low SWR in all Console Switch positions, the RCS-4 Remote Switch box rebuild was successful. The total cost to rebuild the RCS-4 switch box was approximately $47 versus $199 for an entirely new RCS-4. The total time to rebuild the RCS-4 switch box was 2 hours.

 

Rebuilt Remote Switch Box PC board

 

 

 

 

 

 

 

 

 

Rebuilt Remote Switch Box Base Plate