Background
The BBC Television Centre was designed with the basement or ‘hub’ being set aside for the new technology of videotape recording, the idea being that the cable runs to each studio were kept as short as possible.
The 2-inch ‘quad’ Ampex machines were very much new technology and were phenomenally expensive to buy. In 1960 the BBC was paying around £30,000 per machine. Bear in mind that around that time the cost of the average house was only £3,000. By comparison, in November 2008 an average house cost £224,000. That would put the price of a VT machine today at £2.24m!
[http://www.tvstudiohistory.co.uk/tv%20centre%20history.htm#vt]
Jeff Booth
In the days before electronic editing the tape had to be physically cut (between the video tracks) and in (for colour) the correct field blanking interval.
There was an additional pulse recorded on the control track so the exact point could be identified.
To see this (edit) pulse, iron filings (suspended in alcohol) were wiped (with a cotton bud) to ‘develop’ the tape in the area where this control track was located.
The tape was laid oxide side up on the splicer.
The splicing tape was fixed to the back of the tape. To make things even more difficult, the audio was recorded further down the tape so some very devious techniques were developed (using a non timecoded (!) ¼” tape machine) to tidy up the audio.
The EMT2 splicer had a rotating audio head (to play the control track while the tape was stationary) and display it on the built in oscilloscope. This removed the need to ‘develop’ the tape.
Pat Heigham
I still have a bottle of suspended iron filings in alcohol, really to discover what track sense my archive 1/4" reels are!
I do remember working alongside a super VT editor trying to mend the BBC pantomime show.
He was physically cutting the 2" Ampex while I was editing to match the sound on 1/4" off a TR90.
I recall that we recorded a burst of TIM, the speaking clock at the head of both the video and audio tapes. No time code in those days – hadn’t been invented!
The show itself was a bit of a disaster – I think Norman Wisdom was starring, and the show wasn’t
that good, he had to ask the audience not to throw their balled-up programmes onto the stage. All rather pitiful. Probably one which benefited from being wiped!
Geoff Fletcher
One of my memories of 2 inch Ampex machines was when Anglia TV’s first colour scanner bounced and bucked its way along a old brick hardcore surfaced lane to its parking position at Fakenham Races on its maiden outing. We camera crew watched the unsteady progress with some interest, making jokes about dry joints and the like, while the Engineering Super on the truck, who was standing with us, gradually became more and more worried. Eventually the OB parking area was reached and the truck parked up. Des – said Engineering Sup – opened the door to the VT area and turned white. The jolting had shaken one of the Ampex cabinets off its moorings and it was tilted at a sharp angle to the deck, only prevented from falling completely over onto its front by the top edge being caught on the door frame lip! He closed the door very gently and gingerly boarded the truck via the racks door accompanied by a couple of large riggers on tiptoes, and together they got the thing back into place without any damage.
Bernard Newnham
In 1986 we had a celebration that they called “TV50” – fifty years of television. Part of it was to run a whole load of ancient programmes on BBC2. I was given the job of making the trails, so I was the first person to get the tapes out for a long time. It was good job that I looked before Radio Times was published, as for various reasons a number on the original list weren’t suitable, and I had to make an appointment with Controller 2 and give him the bad news. Some just weren’t right – the last episode of the soap “Z Cars” instead of one of the original ones – but the worst was the first episode of “Up Pompei”. We put the tape on and within a minute or two we had huge dropout – white powder time. There was no backup in those days. I don’t know what they did about that one, but we got hold of a later episode which didn’t fail the play test.
Jeff Booth
There is a way to rescue a ‘White Powder’ victim.
The tape can be baked (by someone who knows what they’re doing). The resulting tape is ‘stable’ for (about) a week. Long enough to make a copy. I would imagine the VT ops in question were ‘children’ with no experience of ‘proper telly’ or any of the associated problems.
It wasn’t just Videotapes that suffered. Audio multitrack 2” tapes also suffered, as did ¼”.
1” VTs also had problems. Tapes with a ‘cushion flange’ (a foam rubber coating to the inner surface of the spool) also had issues. The glue decomposed and stuck the tape together into a solid block. Once again, baking fixed the problem.
Disclaimer DON’T TRY THIS ON IRREPLACEABLE TAPES. *EVER*.
I’ve not come across any issues with cassette based formats (although there seems to be a growing issue with old VHS tapes).
Bernard Newnham
… and if the machine is on air, I’m told that a finger nail introduced to the top of the headwheel – which is going round at 14000rpm – might sort the head clog problem. Though only on a standard 2" machine, not an IVC.
Dave Buckley
This technique also worked on the IVC machines but you had to be very careful!
The finger method also worked on Sony Umatics but only after taking the machine apart as I had to do in the 1980s on the billiard table at Wood Norton while out with a portable Umatic unit which decided to head clog! Colclene blown in was only partially successful.
Derek Martin
I watched VT editor Roger Harvey clear a head clog by doing exactly that on a live “Sportsnight” back in the 80s. Worked a treat but don’t ‘arf make a funny smell!
Jeff Booth
…The trick was to use the thumbnail but to always stand to the left or right of the machine (depending if left or right handed) in case the head flew off in the process!
I did know someone who had this happen to him and the head embedded itself in the wall opposite!
Keith Mayes
Ampex (in particular) audio tapes also had this problem but could be fixed by ‘baking’ in an oven (and then a copy made) We had an oven and transferred many a copy of years ago (hundreds) in Slough; it worked well! Also in the eighties we had a 2" VT editing block in TMS, which we used for 2" multitrack tape editing. Worked really well.
Dave Buckley
Jeff Booth’s explanation of the reason for the title (“White Powder Christmas”)is very accurate.
I can go back to the very early 1970s when TV Training acquired an IVC 1" helical scan VTR on which we recorded course final productions. These would probably be viewed a couple of time each (usually playing back to a head of a department in TVC) then into store for two years until the tapes (Scotch brand) came up for reuse.
Then we started finding a white deposit on tape guides and getting head clogs. The matter got so bad that we called in an IVC engineer and a rep from Scotch at the same time (and introduced them to each other!)
The rep confirmed that it was the binder causing the problem and that the only suggestion he could make to try and avoid head clogs, was to spool the tape through a few times and clean the machine after each spool. This did go some way to alleviating the problem, but it didn’t go completely until we
changed the in-house VT format to lowband Sony U-matic.
