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by actionfromafar 1432 days ago
Eh, no. Think about it. If the audio was encoded in the video signal, it would need to be buffered. (Such systems existed, but not in VHS.) Audio in VHS is a continuous analog thing.

But no need to speculate:

https://en.wikipedia.org/wiki/VHS

1 comments

You’re thinking digitally. PAL and NTSC are analogue formats. In fact that link you cited even says that’s VHS stores the PAL or NTSC signal verbatim and what I described is exactly how PAL and NTSC store audio.

To quote:

> Each of the diagonal-angled tracks is a complete TV picture field, lasting 1/60 of a second (1/50 on PAL) on the display. One tape head records an entire picture field. The adjacent track, recorded by the second tape head, is another 1/60 or 1/50 of a second TV picture field, and so on. Thus one complete head rotation records an entire NTSC or PAL frame of two fields.

Edit: This a diagram here https://en.m.wikipedia.org/wiki/NTSC that illustrates how each transmissions frequency is divided up for different aspects of the broadcast.

I am not thinking digitally.

VHS stores the video as it was broadcast.

But how the audio is stored, has nothing to do with that.

https://en.wikipedia.org/wiki/Analog_television

There were different ways to transmit audio over the air waves, but it was done on a different frequency from the video. There were even schemes to broadcast the audio on regular FM stereo as. Some VCRs had a separate audio in so you could use a separate audio source for instance for dubbing. (But you had to record video at the same time, because of the head switching. So no going back and edit only the audio or only the video, with VHS.)

The audio on VHS was originally stored just like on audio cassette tapes, quoth the VHS wikipedia:

"audio was recorded as baseband in a single linear track, at the upper edge of the tape, similar to how an audio compact cassette operates."

HiFi quote from the same article:

"Hi-Fi audio is thus dependent on a much more exact alignment of the head switching point than is required for non-HiFi VHS machines. Misalignments may lead to imperfect joining of the signal, resulting in low-pitched buzzing"

The audio is not stored at the end or beginning of anything, it's continuous.

https://www.youtube.com/watch?v=IF_rTTptah0

The HiFi audio is recorded "deeper" in the tape, then they video is laid down on top of that.

You're literally now just saying the same thing I was! It was a different frequency on the same signal. I never said it was chopped between frames! That's some weird conclusion you came to all by yourself. Hence why I said you're thinking digitally rather than of an analogue signal. Or at least not realising a broadcast transmission is broadband rather than narrowband.
My mistake then. I triggered on what you wrote "That means audio will be encoded in the signal after the video frame."

It can be interpreted either way (at least by my brain) - chopped up after video, or "after video on the video tape but continuously".

I think this exchange is what they call "violent agreement" :-D