HAMMERLUND HQ-110 RELAY

[W2PFY]

How is the send receive switch supposed to work on the receiver. I looked at the schematic and in the receive position the voltage across the rear jack is about 105 volts with the jumper in place. When switched to transmit or send it falls to zero. I was hoping to be able to use the send position to key a transmitter. Is there anyone out there that has worked with this circuit?

Tnx Terry

[w3jn]

As with most receivers the terminal on the back is for a relay to place the receiver in standby, not to control a transmitter.  You can replace the standby switch on the receiver with a DPDT switch and run the appropriate contacts out the back.

73 John

[WA3VJB]

John's got it right, the HQ-100A that I have is the same.

They provide a breakout point to create a "stand by mode" and it's up to you to implement that with a T/R control system. My suggestion is to take a multi-pole 24V relay or somesuch, and use it to break the line on the '110 receiver, and key your transmitter, and if you have spare terminals, switch the antenna relay over, AND maybe hang a shunt resistor across the speaker of the receive to keep out any stray audio when you're transmitting.