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Old 09-18-2006, 09:08 PM
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wa2ise wa2ise is offline
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Join Date: Dec 2002
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Quote:
Originally Posted by Steve McVoy

Prewar CRTs were relatively dim, and had large beam size, so it is impossible to see the difference between 441 and 525 lines on them.
Looks like all I'd have to do then to create a prewar TV simulation is to defocus a standard NTSC B&W set. And set the brightness and contrast low.

Quote:
Originally Posted by Steve McVoy

As for sound, it is amazing how well slope detection works. Simply detuning the fine tuning control about 100kHz puts the FM carrier on the slope of the IF, and results in detection. Volume is somewhat lower than with a FM detector, but is quite acceptable.
How worse was AM reception of Am modulated sound on a prewar TV channel anyway? I can imagine a fair amount of interference from the video transmission. Especially with modern intercarrier TV sets.

Quote:
Originally Posted by Steve McVoy

FM sound and 525 lines were adopted in 1941, and some prewar sets were retrofitted with FM detectors.
Heard that Sarnoff of RCA freaked when the FCC said "FM for TV sound".... Which meant that he would need to pay Armstrong patent royalties for every TV RCA would make, but he didn't....
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