RE: HiTec Master 7 Transmitter Voltmeter
Have a idea that might work. About 3 years ago there was a battery checker that had led on it and it came with small resistors that you could plug into the checker for 4.8, 6.0 and 9.8v . It was very simular to the "Volt Watch" but you could select your battery voltage.
Sorry I cannot remember the name of the company, but maybe soneone out there can.
It was shrunk wrapped in clear tubing so you could see the red, yellow and green LED's.
Larry