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Old 28th Dec 2018, 11:55 am   #1
Tractorfan
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Smile Professional VTR machines.

Hi,
I enjoyed watching the 'Christmas Tapes' programme with lots of views of the VTR suites.
What puzzled me was why the spools of the VTR machines rotate in opposite directions. Is there any technical reason why the tape is spooled 'inside out', or is it just a design quirk?
Cheers, Pete.
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Old 28th Dec 2018, 12:31 pm   #2
Michael Maurice
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Default Re: Professional VTR machines.

I think it was a design quirk, Ampex machines did this but I understand Sony's don't.
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Old 28th Dec 2018, 1:10 pm   #3
Terry_VK5TM
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Default Re: Professional VTR machines.

Not a 'quirk' but depended on the design of the tape path.

Different companies had there own ideas as to what worked best.

Some could give an instant picture start from standing still and others needed spool up time (early Ampex machines needed 2 second spool up time, later ones were instant start).
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Old 28th Dec 2018, 8:38 pm   #4
Graham G3ZVT
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Default Re: Professional VTR machines.

The Ampex Quad machines needed a w-i-d-e 2" tape because it needed to be axially formed into a canoe shape by a vacuum guide as passed the head wheel, which scanned across the width of the tape. The machine needed a substantial air compressor.

The broadcasters then moved on to 1" C-format machines which used helical scan, and were in principle not unlike domestic VHS and Betamax.
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Old 29th Dec 2018, 1:27 pm   #5
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Default Re: Professional VTR machines.

Quote:
Originally Posted by Michael Maurice View Post
I think it was a design quirk, Ampex machines did this but I understand Sony's don't.
The early Ampex professional 1” machines had a tape path that gave rise to that rather strange tape path (as did their badge engineered Marconi copies), but the later machines took a more conventional tape path. Sony, as you say, always had the more conventional ‘look’ as did RCA’s one and only effort, the TR800, before they started to badge engineer Sony machines.

I enjoyed the programme, it took me back to my early days in telly working on both Quad and 1” machines.
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Old 30th Dec 2018, 12:30 pm   #6
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Default Re: Professional VTR machines.

Excuse my ignorance, but what 'Christmas Tapes' programme do you refer to? I actively seek out footage of old tape drives (mainly minicomputer ones, but anything beyond consumer decks really) and would be interested to watch this.
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Old 30th Dec 2018, 3:16 pm   #7
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Default Re: Professional VTR machines.

This one: https://www.bbc.co.uk/programmes/m0001qqy
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Old 31st Dec 2018, 8:57 pm   #8
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Default Re: Professional VTR machines.

I watched that show, for those who don't know and don't like links, you never know where they can lead you! The Video Tape department of the BBC used to get all the shows being recorded feed from the studios at TV Centre. They would then edit them cutting out out-takes etc and mess about with them before transmission. Some of the VT engineers would put the outtakes and some new material together to make a very rude tape for the staff of the BBC for the Christmas Party. These tapes were too rude for broadcast and never were. However some leaked out to the press. Causing a scandal in the early 80's one year.
The "Christmas" tapes were original started by ITV companies, but were often just sex tapes! So the BBC staff made some less sex ones.
Some of these tapes in the unedited form have been uploaded to YouTube, some quite recently. Some of the older ones are on very poor VHS tapes. They are worth checking out, because even these days the BBC couldn't show some of them!
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Old 31st Dec 2018, 9:19 pm   #9
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Default Re: Professional VTR machines.

I remember a Doctor Who Christmas tape featuring Tom Baker and Mary Tamm (Romana) doing things that were never seen in the broadcasts....

Must have been late seventies and it certainly escaped TV centre, as I saw it at an 8mm sound copying facility I used to do maintenance for.
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Old 31st Dec 2018, 9:27 pm   #10
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Default Re: Professional VTR machines.

That's on Youtube.
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Old 1st Jan 2019, 12:38 am   #11
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Default Re: Professional VTR machines.

Also referred to on the "Elaine Paige and her Bush Radio" thread" [Camtech 25/122/18] Andrew! I can't do links so its not an issue
for me.

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Old 1st Jan 2019, 1:45 am   #12
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Default Re: Professional VTR machines.

I always ended up with the night shift on Christmas Eve for some reason when I was working at TV One in NZ back in the 70's.

About 2am, after all the satellite news feeds were done, along would come the Christmas tape, dubbed onto a special reel of tape that had been liberated from the tape library and then hidden away afterwards for later dubbing and replay.

Never worked out how they managed to get it on the sat feed, considering the cost was charged by the minute those days.
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Old 1st Jan 2019, 2:51 pm   #13
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Default Re: Professional VTR machines.

I think all the engineers along the circuit looked forward to seeing them so I would imagine a blind eye was turned to the nominal costs involved assuming any sort of booking turned up in any system in the first plaice - I would think it unlikely!

As an aside, Channel television in the UK usually made a Christmas tape but had no circuits back to the UK. They would send their tape to one of the mainland ITV companies who would play it out to the rest of the ITV network at an appropriate time.
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Old 1st Jan 2019, 3:57 pm   #14
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Default Re: Professional VTR machines.

Quote:
Originally Posted by Terry_VK5TM View Post
I always ended up with the night shift on Christmas Eve for some reason when I was working at TV One in NZ back in the 70's.

About 2am, after all the satellite news feeds were done, along would come the Christmas tape, dubbed onto a special reel of tape that had been liberated from the tape library and then hidden away afterwards for later dubbing and replay.

Never worked out how they managed to get it on the sat feed, considering the cost was charged by the minute those days.
Were you around when TVNZ accidentally DID broadcast one of those or a similar sex tape - I recall that cause quite a stir at the time and the explanation was some technician left a switch open or similar.
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Old 1st Jan 2019, 8:48 pm   #15
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Default Re: Professional VTR machines.

Quote:
Originally Posted by Grubhead View Post
That's on Youtube.
I`ve just watched that - I seem to remember quite a bit that doesn`t seem to be on Youtube.
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Old 2nd Jan 2019, 1:04 am   #16
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Default Re: Professional VTR machines.

Quote:
Originally Posted by avocollector View Post
Were you around when TVNZ accidentally DID broadcast one of those or a similar sex tape - I recall that cause quite a stir at the time and the explanation was some technician left a switch open or similar.
No Comment

Happened to one of the broadcasters in Sydney sometime later as well (no I wasn't working there).
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Old 2nd Jan 2019, 12:14 pm   #17
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Default Re: Professional VTR machines.

I'm sure I heard a story at some point from someone connected with the technical side of the broadcast industry that Ampex had expensively tooled up and invested in mass production for the deck platter casting of a putative reel-to-reel device in a spin-off (pun unintended!) field that was relatively new to them (perhaps high-speed computer data?) with an involved tape path. When this fell through, the casting was re-purposed for 1" helical scan video but with the awkward counter-rotating spools and the perennial "oxide in/oxide out?" dilemma.

Like so many stories I've heard over the years, I'm reluctant to place too much faith in it, the "three-and-fourpence" effect and unintended misinterpretation by the unfamiliar/uninformed always markedly alter the original facts of a story but the orientation of the early Ampex helical scan machines does seem odd to the point of seeking a reason.
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