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Heatercathodeshort · 4th Mar 2013, 9:29 am

I cannot stress this point more strongly David. Mains derived EHT is lethal but perfectly safe in the right hands with knowledge of the dangers.
Flyback EHT has very poor regulation and tends to collapse when a heavy load such as the engineers hand shorts it out! A small burn usually results and in fact the same process is used in hospitals to seal blood vessels. [I expect they have something more manageable than a Pye V4]
With a 50c/s low impedance supply it does not collapse producing a dangerous shock situation and a very nasty deep burn.
An old service guy friend of mine, now sadly no longer with us used to show me the badly distorted end of his thumb that he had managed to get caught on the top cap of a HVR2 rectifier. I was a young lad at the time but had been playing around with PYE D16T's for quite a while. I was aware of the dangers but that thumb certainly made me even more cautious. I don't want to put guys off but this is not TV22 stuff. If your not aware or are in any doubt, leave these early receivers alone for a while. We don't want the guys in yellow coats to divert all our old junk to the crusher do we?
Regards, John.

4th Mar 2013, 9:29 am	#9
Heatercathodeshort Dekatron Join Date: Jun 2005 Location: Warnham, West Sussex. 10 miles south of DORKING. Posts: 9,147	Re: Vidor 9" table model model CN369A. 1948. I cannot stress this point more strongly David. Mains derived EHT is lethal but perfectly safe in the right hands with knowledge of the dangers. Flyback EHT has very poor regulation and tends to collapse when a heavy load such as the engineers hand shorts it out! A small burn usually results and in fact the same process is used in hospitals to seal blood vessels. [I expect they have something more manageable than a Pye V4] With a 50c/s low impedance supply it does not collapse producing a dangerous shock situation and a very nasty deep burn. An old service guy friend of mine, now sadly no longer with us used to show me the badly distorted end of his thumb that he had managed to get caught on the top cap of a HVR2 rectifier. I was a young lad at the time but had been playing around with PYE D16T's for quite a while. I was aware of the dangers but that thumb certainly made me even more cautious. I don't want to put guys off but this is not TV22 stuff. If your not aware or are in any doubt, leave these early receivers alone for a while. We don't want the guys in yellow coats to divert all our old junk to the crusher do we? Regards, John.