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B&W Antenna Switch Repair

 

B&W Antenna Switch Repair

Filed in Accessories on May.10, 2021

Some time in the past, I have picked up several of the B&W Antenna Switches at a hamfest. They were purchased at a good price, just $10 each, and appear to be of pretty good quality. I got two 6-position switches (B&W Model 595), and two 3-position switches (B&W Model 593).

Last month, I decided to put them to use in my remodeled hamshack. So I dug them out of the parts bins, and gave them a quick multimeter test.

One of the 6-position switches had a problem with the grounding arrangements for unused connections. As they are switched from antenna to antenna, they are supposed to put a ground on all connections except the one currently in use. This switch was not doing that.

 
B&W 595 Antenna Switch as Received

I opened up the switch and did a visual inspection. I found that the switch contact for the common ground connection had been irretrievably burned, such that it no longer made contact.

Being a cheap, lazy ham, I didn’t want to find and purchase a new (to me) ceramic switch. 

 
Burned Switch Contacts

So I decided to sacrifice one antenna connection for the good of the whole, and used that contact to provide the missing ground to the rest of the connections.

This was pretty straight forward, as all that was involved was to remove the connection to the extra antenna port, and route that connection from the switch to ground. I selected the last antenna port to sacrifice, and cut the wire going to that port. I crimped and soldered a ring terminal to the end of the wire from the switch, just long enough to reach the mounting screw next to it. Then I removed the nut and placed the ring under the nut. After replacing the nut and tightening, here is what it looked like.

 
Ceramic Wafer with extra ground lug

While completing this task, I did manage to break one of the other wires to a different antenna port. I fixed that with a crimp lug and some solder. It’s not rocket science… I also touched up a couple of solder joints on the switch that appeared to be cold joints. Finally, a couple of the SO239 connectors were not held tightly to the case, which they rely upon for a ground connection. I drilled out the loose rivets from the bad connections, and replaced them with some 4-40 hardware to hold everything tight.

 
SO-239 with new mounting hardware

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