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mikeydee · 3rd May 2017, 8:01 pm

Hi, I am having a problem testing a PX4 valve on my Sussex. I have not tested a directly heated valve before so maybe it's me doing something silly.

I connect the ext-heater -ve terminal to the cathode and then connect up the valve as normal. But I am getting massively off readings like Gm=100 and Ia=80mA I am expecting something like 40mA and 6.

Any ideas?

3rd May 2017, 8:01 pm	#1416
mikeydee Tetrode Join Date: Aug 2011 Location: Bristol, UK. Posts: 67	Re: The "Sussex" Homebrew Valve Tester. Hi, I am having a problem testing a PX4 valve on my Sussex. I have not tested a directly heated valve before so maybe it's me doing something silly. I connect the ext-heater -ve terminal to the cathode and then connect up the valve as normal. But I am getting massively off readings like Gm=100 and Ia=80mA I am expecting something like 40mA and 6. Any ideas?