[Electronic M]

Originally Posted by DVtyro

Um... Er... I need to read up on how flying spot scanner works

It has two capstans and two pinch rollers (not mentioning Nakamichi system here).

I would imagine that if tape...er um film tension could be maintained via the reels that it could work fine with a single capstan system for autoreverse...I own a TEAC X-3R and it's later identical cousin the X-300R that are 3 motor single capstan auto reverse stereo RTR tape decks... Most other RTRs especially ones that could record in both directions (the Teac only recorded in one direction because it only 3 had heads and erase would be on the wrong side of the record head in reverse) had 2 capstans as did most autoreverse cassette decks, but there's probably a single capstan auto reverse cassette deck out there too.

I don't know if there's any good videos of the B&K 1077 analyst out there but it too is a flying spot scanner....In a nutshell a magnetically deflected camera tube is always going to be significantly more complex and expensive than a CRT. A high speed light sensor that only measures the light of one fixed point is always going to be cheaper than a camera even if it needs a CRT display tube to be paired with it to do the scanning for it*....Which is exactly what a flying spot scanner CRT does. In a flying spot film scanner the film frame is placed over a CRT with short persistence phosphor (essentially only the point on screen that the beam of the gun is on at that instant is lit) set up to create a blank white raster...The CRT light projects through the film and since the only light at any given instant is from the specific spot on the film over the light from the CRT screen at the point the beam is at at that instant the light that passes through the film is exactly what the base band video signal looks like minus the sync (which would be added later) and a simple cheap single point photoelectric device can convert the light to electronic video.

*Heck in the late 60s Sylvania came out with the slide theater console it was a 23" color TV packaged with a full color flying spot slide scanner. It used a hidden smaller white phosphor CRT that projected through the film onto dichloric mirrors that split the light into separate R, G, and B primary color paths that each had a photoelectric device (photo multiplier tube IIRC) to convert them to electrical signals that were passed the main (color) CRT the viewer would watch.