RE: TV nostalgiaAnd lest we forget the Hallicrafters electrostatic deflection systems. You could sure get a poke off those.
Ralph Cameron ----- Original Message ----- From: Ehler, Kyle To: 'Rich Nute' ; 'EMC and Safety list' Sent: Friday, August 03, 2001 9:23 AM Subject: RE: TV nostalgia My experience was with the Packard-Bell transistorized models. I think the aversion I have was prejudiced by the fellow who mentored me. I had little reason to doubt, but then the sets I worked on, had a callback history that may have been created by my mentor. -kyle -----Original Message----- From: Rich Nute [mailto:ri...@sdd.hp.com] Sent: Thursday, August 02, 2001 5:36 PM To: emc-p...@majordomo.ieee.org Subject: TV nostalgia Okay... more nostalgia and a bit on safety back in those days... so that we don't stray too far from the subject matter of this forum. My first TV was a Motorola 7-inch round in a Bakelite cabinet. The speaker was the same size as the CRT. My second was the famous RCA 10-inch round chassis with 32 tubes. I could pull out 15 tubes and still have a usable picture. Kyle mentions Packard Bell, which I considered a straight-forward, good product. It used the Standard Coil turret tuner. The one that won my respect was Muntz TV. It was CHEAP! When you looked inside the chassis, there was nothing there compared to the other TVs. They really knew how to take the cost out of the TV! Amazingly enough, its picture was among the best, and its reliability was indeed the best -- no parts to go bad! The company was owned by "Mad Man Muntz," the classic Los Angeles used car dealer. In the mid-fifties, GE came out with a transformerless 17-inch TV. One side of the power line was tied to the chassis (2-wire plug back in those days). The only protection was the plastic knob on the shafts of the various controls. When servicing this TV, you quickly learned never to touch the chassis! The power supply was a simple full-wave rectified power line. The tube heaters were connected in a series-parallel arrangement. These sets were the initiation of UL's investigation into antenna coupling capacitors. These capacitors provided the isolation between the TV antenna terminals and the mains voltage. TV sets of those days consumed between 400 and 600 watts. When they were turned on, the cold filaments were a very low impedance, so the turn-on current was very high. The off-on switch was often mounted on the back of the volume control. Eventually, the contact resistance of the switch would grow to the point where the I**2*R power would melt the solder and the power wires would come loose. It was common to have a customer report that his TV was dead, and it was due to the lack of a good connection to the switch. At one company, we had metal bat-handle toggles blow out of the switch due to the cold filament load. Out of this experience, UL developed the requirements for the TV-rated switch, which had specially-designed contacts that would not overheat when used in a TV or similar application. Best regards, Rich ------------------------------------------- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Michael Garretson: pstc_ad...@garretson.org Dave Heald davehe...@mediaone.net For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: http://www.rcic.com/ click on "Virtual Conference Hall,"
