Photo of GRC-9 receiver (new battery fitted)
My radio had an incorrect dry battery fitted, with 2 pins soldered to an incorrect battery, covered in insulation tape and loosely pushed into the connector.
Photo of old and new battery.
I found a battery plug, and glued a plastic tube to it. I dismantled an AA cell type battery holder, and removed the positive terminal contact and the negative spring contact. I soldered 2 wires to these, and soldered them to the plug terminals inside the tube. The big pin is positive. I placed the positive contact at the bottom of the tube, suitabley insulated, then placed 3 hearing aid cells inside the tube, to give approximately 4.5 volts. I placed the spring as the top contact, then glued a fibre washer to the top, to hold it all together. It was clamped while the epoxy glue cured. The battery voltage was checked, then it was plugged into the radio and the clamp tightened. Simple, looks the part and works fine.
Photo of GRC-9 and new battery
This radio was written up by Mike Hoddy G0JXX in the VMARS Newsletter Issue 32 December 2003, and he describes the bias battery.
Copyright Ray Robinson 2011