Here, Hitachi and RCA had quite the relationship. They built bigscreens for each other. You could open up an RCA and find a Hitachi or open up a Hitac hi and find an RCA. The last two it seems were Mitsubishi and Sony if you a ctually wanted their product, everyone else eventually would just buy whate ver and have it rebadged.
as hard to get transistors that could handle the current. "
Did not run into that problem. I did have some small Emersons that were har d to get a damper diode for because it was such high current. But not an RC A. But you said RCA tubes, that is not the fault of the tubes. It is the fa ult of the engineers.
ryone else's patents. Their 70s power supply designs are a Rube Goldberg's nightmare wrapped in a chain saw wielding mass murderer's warm embrace. Th ey weren't notably efficient or particularly well regulating, so my guess i s that they were building a unique design with no patents (and really, who would patent such an abortion?).
g" attempt. Well Sony power supplies committed harakiri at not much less t han 100VAC, and lots of Trinitrons were blowing up during the brown-outs.
hink the tube was very finicky and required far more stringent manufacturin g tolerances than the typical tube, hence the cost. Give it a small nudge and the shadow mask would shift or one of the wires would snap. Early tubes had the coaxial second anode connector and those tubes would short interna lly.
I remember the PSU boards in 70s trinitron sets. Talk about unnecessarily c omplex. As an experiment I once replaced the PSU board with a lightbulb as a dropper. (I forget how I provided filament power.) It worked, though volt age instability caused picture height instability.
I liked those sets as they were well valued but CRT emission tended to go. No-one else had worked out how to get the emission back, I did.
With monitors - I discovered that some 'genius' at Philips had published a bulletin stated that stable SMPSUs meant CRT heaters only needed 6.15V. Most manufacturers fell for it, and most CRTs ended up with poisoned cathodes.
There was plenty of evidence that some engineers were just turning the wick up in the PSU. My solution was to fit a Shottky-barrier heater rectifier, that needed an added snubber to prevent the flyback peaks killing the rectifier, and improvements to the filter circuit. Some already had Sb rectifier, so there wasn't much I could do.
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