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Old 07-25-2012, 07:09 PM
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wa2ise wa2ise is offline
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"13 thousand times a second". That would imply that this TV system was the 441 interlaced line system, before it was bumped up to 525 lines. 441 times 30Hz = 13230Hz. as it was 30 frames a second, or 60 fields of 441/2 lines a second. In today's parlance, 1939 TV was 441i 60Hz. Also the sound if I recall correctly was to be amplitude modulated. Which would have sounded horrible in an intercarrier receiver.

If you wanted to, you could fake the appearance on an NTSC B&W set of a 441 line TV signal by using a CECB set to letterbox mode, and setting the vertical height to be overscanned enough to lose the top and bottom black areas. And have excessive overscan on the horozontal to make the geometry of the image look right. Use the luma output if your box has S-video available. Letterbox mode reduces the vertical resolution of the video image to something like that of 441 lines interlaced. Actually it's worse than that, it's about 394 lines, but close enough... If you are really crazy, you could build a 1939 style cabinet that houses a B&W CRT NTSV TV set, and make the mask on the CRT much smaller than the CRT, to crop the letterbox black areas top and bottom, and cropping the side areas to make it 4:3 aspect ratio.
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Last edited by wa2ise; 07-25-2012 at 07:24 PM.
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