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Heatercathodeshort · 4th Apr 2010, 5:26 pm

Its not actually heat paper Chris but a very clever thought. [Bakelite can withstand quite considerable heat.] Its metal backed paper, cabinet screening in a partial attempt to stop the radiation of the line timebase. 10.000 kc/s would divide very nicely by 200kc/s the frequency of the old Light Programme on Long Wave. A radio placed on the opposite wall to the television receiver in a 30's semi would be completely drowned out by the whistle! The capacitor connected across the set side of the on/off switch [that explodes to everyone's shock] also short circuits line frequency that has sat itself on the mains supply. Its not a problem today because very few people listen to A.M. radio. In this area, W.Sussex I don't know anyone who has A.M. tuned on their car radio's. When doing service calls in the 60's you would hear the line timebase radiation rise and fall on your car radio as you drove down a suburban road. Just like being a television detector van! Regards, John.

4th Apr 2010, 5:26 pm	#118
Heatercathodeshort Dekatron Join Date: Jun 2005 Location: Warnham, West Sussex. 10 miles south of DORKING. Posts: 9,147	Re: Tv62 Its not actually heat paper Chris but a very clever thought. [Bakelite can withstand quite considerable heat.] Its metal backed paper, cabinet screening in a partial attempt to stop the radiation of the line timebase. 10.000 kc/s would divide very nicely by 200kc/s the frequency of the old Light Programme on Long Wave. A radio placed on the opposite wall to the television receiver in a 30's semi would be completely drowned out by the whistle! The capacitor connected across the set side of the on/off switch [that explodes to everyone's shock] also short circuits line frequency that has sat itself on the mains supply. Its not a problem today because very few people listen to A.M. radio. In this area, W.Sussex I don't know anyone who has A.M. tuned on their car radio's. When doing service calls in the 60's you would hear the line timebase radiation rise and fall on your car radio as you drove down a suburban road. Just like being a television detector van! Regards, John.