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PJL · 17th Feb 2017, 1:56 pm

If you look at the circuit, you will see that the resistors are joined at one end and are connected through the low resistance valve filaments at the other. With the PX4's in circuit, an in-situ measurement will see the other resistor and the filaments in parallel hence why you measure 11 ohms.

I was an idiot and didn't look at the circuit correctly and this measurement won't work!

The best option for checking the anode currents is to measure the voltage across R47 and R48. BUT, this is at very high and lethal voltage and without R50 and R51, the capacitors will retain the high voltage for a long time after switch off.

17th Feb 2017, 1:56 pm	#151
PJL Dekatron Join Date: Sep 2005 Location: Seaford, East Sussex, UK. Posts: 5,997	Re: Restore a Beau Decca If you look at the circuit, you will see that the resistors are joined at one end and are connected through the low resistance valve filaments at the other. With the PX4's in circuit, an in-situ measurement will see the other resistor and the filaments in parallel hence why you measure 11 ohms. I was an idiot and didn't look at the circuit correctly and this measurement won't work! The best option for checking the anode currents is to measure the voltage across R47 and R48. BUT, this is at very high and lethal voltage and without R50 and R51, the capacitors will retain the high voltage for a long time after switch off.