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A comment on How Photos Were Transmitted by Wire in the 1930s. Parent comment

Re:How Photos Were Transmitted by Wire in the 1930s by rightbyte on Wednesday March 13, 2024 @03:27PM (#39696216)
Does the belinograph need syncing though? I imagine you would just have a waste ribbon around the photo and start it after the call with say a delay you both agreed too. Or maybe you could send light in some known pattern with a starter strip and the receiver could look at the lamp.

Attenuation most have been a problem though? I guess you could send some sort of calibration photo to adjust gain? I don't think practical FM signal modulation was a thing yet in the 30s?

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Re:How Photos Were Transmitted by Wire in the 1930s by barrkel on Wednesday March 13, 2024 @06:04PM (#39698143)
You need to synchronize the spin rate of the drums on either end. If there's a difference of half a rotation over however many hundreds (thousands?) of rotations to transmit the photo, you'd end up with a completely distorted picture.
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