When did high-voltage transistors become common?

Haha! Thanks George, my daughter is marrying a Zambian in Zambia. Have spied zebras and antelope but heffalump are elusive. Travelling during a pandemic is weird.

piglet

ll solid state except for the horizontal drive!

y only used a vacuum tube for the HV rectifier and the CRT. The audio outpu t transistor was around 125VDC. It used an Allen Bradley carbon comp resist or for a fuse, Anything else wouldn't open in time to protect the output tr ansformer.

t.

Yes. Car radios were initially all HT valve, then ponly the output valve ne eded HT, then 12v valves but an output transistor. My hybrid one proudly sa ys 'transistor' on it, well it does have one.

NT

Awesome! Some hope for grand kids to spoil then. (Or perhaps you have 'em already?) My son has had a girl friend for several years... which looks promising. My daughter is more interested in other women, which doesn't make kids impossible, but does need some external input.

George H.

Couple of tubes, (8068 from memeory) in my Fluke 415B high voltage psu, Rest is solid state, other than a gas tube voltage reference. HP BWO based sweepers and spectrum analysers used similar tubes for the hv sweep.

Also have a fluke 335 1000v voltage standard here that uses a huge Westinghouse transistor in the series regulator. Bolt style package base with 3 tag pins out the top...