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PJL · 15th Jan 2012, 9:03 pm

I have looked at the voltages and I will try to explain the problem ones:

1) UL41 pin 1 and pin 8 are the heater. They are showing a heater voltage of 18V and not the 45V it is supposed to be. As a consequence all the other heater voltages are high. It could be:-

a) the valve had not warmed up b) the valve is the wrong type c) The valve has a heater short

2) UL41 pin 2 is showing as 0.9V. This is the anode and it should connect to the output transformer and read roughly 250V. This means the output transformer is a) not connected b) open circuit

3) UL41 pin 4 has a green wire attached showing as 257V. Pin 4 is not used so it is being used as a tag to hold a component which appears to go to pin 6 grid? The component looks like a resistor so the grid is at 257V and it should be 0V.

15th Jan 2012, 9:03 pm	#61
PJL Dekatron Join Date: Sep 2005 Location: Seaford, East Sussex, UK. Posts: 5,997	Re: Bush AC34, no sound. I have looked at the voltages and I will try to explain the problem ones: 1) UL41 pin 1 and pin 8 are the heater. They are showing a heater voltage of 18V and not the 45V it is supposed to be. As a consequence all the other heater voltages are high. It could be:- a) the valve had not warmed up b) the valve is the wrong type c) The valve has a heater short 2) UL41 pin 2 is showing as 0.9V. This is the anode and it should connect to the output transformer and read roughly 250V. This means the output transformer is a) not connected b) open circuit 3) UL41 pin 4 has a green wire attached showing as 257V. Pin 4 is not used so it is being used as a tag to hold a component which appears to go to pin 6 grid? The component looks like a resistor so the grid is at 257V and it should be 0V.