I designed this improved version of the relays card after receiving a request from a visitor of this site: after he built this project,he asked me if there was any way he could automatically ground the antennas not in use.

This useful function can be easily implemented,using a different type of relay (with two sets of contacts),as shown in the schematic.

The first set of contacts will work exactly as it was in the original project,while the second set,to be more specific,the normally closed contact only,will be used to ground the relevant antenna.

As soon as the relay will be energized,the related antenna will be simultaneously connected to the radio,and disconnected from ground.

The only antenna that is never grounded is the # 5,that,as explained in the previous pages,it's the main antenna (in case of loss of power,this antenna will be automatically selected)  [<<PREVIOUS]



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