UK Vintage Radio Repair and Restoration Discussion Forum - View Single Post - Mullard 3-3 voltages query

PJL · 9th Apr 2021, 2:12 pm

The EF86 anode load looks like 1.5M not the 1M in the Mullard design?

The EF86 anode voltage reading in the Mullard documentation is lowered by the 2M AVO 8 input resistance. Even the 10M of your DMM will have an impact.

You need to make sure it is not oscillating as this will affect the DC measurements. If it is stable then the EF86 is probably weak.

9th Apr 2021, 2:12 pm	#11
PJL Dekatron Join Date: Sep 2005 Location: Seaford, East Sussex, UK. Posts: 5,997	Re: Mullard 3-3 voltages query The EF86 anode load looks like 1.5M not the 1M in the Mullard design? The EF86 anode voltage reading in the Mullard documentation is lowered by the 2M AVO 8 input resistance. Even the 10M of your DMM will have an impact. You need to make sure it is not oscillating as this will affect the DC measurements. If it is stable then the EF86 is probably weak.