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sexton_mallard · 23rd Jul 2017, 4:50 pm

The LOP valve PL81 does look to be working hard. In darkness a slight blue glow can be seen in side the electrode structure. The anode plates do look to almost be red but it difficult to see from the heater glow. I have never looked at one of these close up in a working set before so I don't really know what normal operation looks like. I appreciate the circuit has a lot of energy. Certainly the line whistle suggests this. I will take a picture later.

I could not get any arc from the anode cap of the U26, or from the connector either.

23rd Jul 2017, 4:50 pm	#28
sexton_mallard Heptode Join Date: Sep 2013 Location: Ellesmere, Shropshire, UK & Co. Cork, Ireland. Posts: 501	Re: Kolster Brandes RV 10 (Crown) The LOP valve PL81 does look to be working hard. In darkness a slight blue glow can be seen in side the electrode structure. The anode plates do look to almost be red but it difficult to see from the heater glow. I have never looked at one of these close up in a working set before so I don't really know what normal operation looks like. I appreciate the circuit has a lot of energy. Certainly the line whistle suggests this. I will take a picture later. I could not get any arc from the anode cap of the U26, or from the connector either. __________________ Dom Less snakes...more ladders!