On the Simpson 260 VOM ,R10K range it uses a 15 volt zinc carbon battery. I sub a 15 volt Alkaline battery. this works good ,But has one Problem, Due to the relaxation effect of the alkaline battery you need to delay 10 seconds for the battery to stabilize. Then it is stable.

 

On the Simpson 260 VOM ,R10K range it uses a 15 volt zinc carbon battery. I sub a 15 volt Alkaline battery. this works good ,But has one Problem, Due to the relaxation effect of the alkaline battery you need to delay 10 seconds for the battery to stabilize. Then it is stable.

The Taylor 100k/V meter I have uses a 30V battery - when that became unobtainable, I built a miniature blocking oscillator inverter that fit in the battery compartment.

The inverter was pretty much the Joule-thief circuit, so it run from the low Ohms 1.5V battery via a push button.

Regulation was nothing more complex than shunting the rectified output from the secondary winding with a zener.