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Most sets of that time had a metal chassis (even the early ones that used circuit boards then had a chassis) and the chassis would be grounded. On most sets that had metal cabinets(portables, and cheaper table model sets) the cabinet would also be grounded.
Another potentially lethal scenario that is more possible is the series string power supply type sets which tied chassis ground to one side of the non-polarized plugs of the day. Chassis ground and actual ground could be at lethally different potentials back then, and on series string sets(the series string design dates back to radios of the 1930's BTW) if one pluged the set in backwards (very for easy anyone to do back then) the chassis could be at full power line voltage, and despite (often inadaquite) precautions the user could still get in contact with that voltage (a few B/W portables were notorious for having the precautions fail and the metal cabinet being connected to the hot lead of the powerline. On carpet, lenolium, wood floors or when a person is standing rubber in shoes this is not a serious danger, but bare foot on tile, cement, or out side the juice from a messed up series string set can be lethal!
Few people had color sets between 1955 , and 1960, becaues color was new (the "modern" NTSC standard was only created in 53' or 54'), and sets were expensive ( we are talking between new luxury car and a really good used one expensive). So if someone has a color set they either have good money, are technically skilled and pieced one together from junkers, paid a lot for a used one, or stole it.
If your technician is old then he probably started out as a radio repair man, and then transitioned to TV 10-20 years before the story is set. Some techs got mega confused by color (there was a primitive half mechanical standard that was dumped shortly after inception and there were many competeing and evolving experimental standards that were all swirriling around to confuse and daunt techs prior to the standardization), and simply got fedup deciding to refuse to work on color sets untill the survival of their bussiness hinged on it.
Techs of the day varied from the "replace the tubes and hope it works" hap-hazard loonies, to those who were good at finding and fixing any fault and had decent knowledge of the circuits, to retired or working engineers trying to earn some side money who not only could fix a set, but could design a TV or someting much more complex. Many techs in busy/profitable shops also hired an errand/house call boy to handle simple work at the shop and do the "so simple and manotenous I could train a monkey to do it" house calls (when what they were trained or knew how to do did not fix the problem they would take the set or the chassis back to the shop for the more experienced tech to deal with).
Current kills not voltage and for current to flow through one, one must touch two points at different voltages that can supply a large current. For example birds can stand on a power line and not get killed because they are not touching anything else but the line. But if a larger bird was to stand on the line and flap it's wings into the wood pole or an adjacent wire it would fry like a christmas goose. For current to be most lethal it must flow through the heart, and the most commonly occuring paths that facilitate that are current flowing between the two arms, or between the arm(s) and leg(s).
A non-electrocution way that one can be killed working on TVs is exploding metal can type electrolytic capacitors. They explode when connected backwards or to a voltage sutably beyond their rating. A friend of a friend had one explode in his face and was injured so bad that he had to give up this hobby. The older can type lytics were as big as tubes. When lytics explode the metal can usually stays intact and shoots off of the base terminals like a rocket due to steam pressure from mineral oil that boils when the cap over heats from the above mentioned circuit conditions (the insides of the cap can catch fire after the can goes flying).
I know from experience that electrolytic caps can be verry dangerous when allowed to explode. I used to (in my teen years) take caps I had scrounged from 70's stereo equip., and blow them up under safe controlled circumstances outside to entertain myself and my friends. Some of the larger ones that I fired (about 1/8 to 1/32 the size of what are found in tube TVs) could shoot across the street (a total distance of as much as three street widths), and the distance traveled seemed to be proportional to size so I can only immagine what the damage the type found in tube TVs could cause.....maybe enough to punch a hole cabinet and keep going.
Tom C.
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