AVO VCM163 - Some faults I have had - Page 2 - UK Vintage Radio Repair and Restoration Discussion Forum

Fourlegsgood · 2nd Jun 2016, 2:00 pm

Heat voltages on VCM163.

The no load heater voltages on my 163 match pretty well to the Heater Volts knob settings. However, the actual heater volts on the 163 drops when a valve is inserted and is under load, eg 2A3 valve causes a drop to ~ 2 volts, down from 2.5v.

Is this usual? The same valves in my amps do not cause a similar voltage drop.

Not worried, just curious.

2nd Jun 2016, 2:00 pm	#21
Fourlegsgood Tetrode Join Date: Feb 2015 Location: Leicstershire, UK. Posts: 81	Re: AVO VCM163 - Some faults I have had Heat voltages on VCM163. The no load heater voltages on my 163 match pretty well to the Heater Volts knob settings. However, the actual heater volts on the 163 drops when a valve is inserted and is under load, eg 2A3 valve causes a drop to ~ 2 volts, down from 2.5v. Is this usual? The same valves in my amps do not cause a similar voltage drop. Not worried, just curious.