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#1
05-26-2009, 09:24 AM
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2" tape V.T.R.
How was the image provided by 2" tape V.T.R.'s. When these machines where last used?
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#2
05-26-2009, 11:21 AM
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Not bad. I've seen one in operation at the KTLA TV studio in Los Angeles while UCLA was restoring a show, which was stored on that 2" format. I can't answer when they were last used, but the one I saw, as far as I know, is still functional, and there are still a few tapes out there floating around. That 2" machine was moved from KTLA to another location in the past few years.
Charles
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Collecting & restoring TVs in Los Angeles since age 10
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#3
05-26-2009, 11:53 AM
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I used one in 1993, KOFY San Francisco. Both RTR and cart playback.
Quality? Ehhh, not bad. Major pain in the ass to setup and keep running though.
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I've crossed lines of words & wire, and both have cut me deep... No, liquor does not make you charming. That's what peyote is for.
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#4
05-26-2009, 01:03 PM
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I read that the heads on the Quadraplex machines have very short lives.
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#5
05-26-2009, 01:30 PM
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The head runs super-fast, and is a "screw" scan and not the same helical scan that we're used to seeing in VCRs. If that thing ever got loose, it would act like a ninja throwing star.
 It spins so fast that it literally screams a high pitch, like a turbocharger.Charles
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Collecting & restoring TVs in Los Angeles since age 10
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#6
05-26-2009, 02:37 PM
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Where can I found more infos about "Ampex" VR2000? The VR2000 which didn't had a monitor and the one that had a extension with a monitor where named differently?
How much is in kilograms 1300 pounds (I heard this is the wheight of this machine).
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#8
05-26-2009, 03:33 PM
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So that machine weights a half of a metric tone or even more?
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#10
05-26-2009, 04:34 PM
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Quote:
http://www.lionlamb.us/quad/ampex.html The quality of standard high-band Quad is better than 1" C-format, less noise, richer colour, and a bit more resolution without moire. Quad Ultraband and Quad superband/Pilot, used to master commercials, are the best quality analog video system ever made, it was still in use into this century. Quad was also the first system to support digital recording. The standards derived were used in the D1 and modified for D2. It has been said that it was a mistake to drop quad in favour of the D1 as a mechanical base, Quad machines, such as the AVR 3, were becoming quite portable and sophisticated. Last edited by MelodyMaster; 05-26-2009 at 04:45 PM.
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#11
05-26-2009, 11:59 PM
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2" tape! One of my favourite subjects from my early days in broadcasting. I was using them in to the late 80's when 1" type C did them in.
If I remember right, the recording method was called "transverse recording" as opposed to "helical recording" on slant-track machines. Each of the four heads had it's own input and output amps with the usual adjustments. Setup was the PITA like Justen said. To set the record bias, there was a microphone built in to RCA machines. You would do a test recording and announce the settings on each amp. "1", "1.5" and so forth over four amps. Then you would check the RF envelope on playback on the scope and choose the setting that was optimum from listening to your own voice announcing the settings over four amps. To play back, you threaded the machine and played the color bars and had to adjust each head amp for equal luma/chroma on the scope in the vertical mode to make each head equal. That usually took 20-30 seconds. Then you found the start of the commercial/show and backed up the tape 7 seconds. Now it was set for playback as it took most of the 7 seconds for the machine to come up to speed and lock for playback. When I was directing local news in the day, our news anchor would raise his pen on camera as a signal to start the playback for the tape to appear 7 seconds later. If the public only knew how tv gets to their set. Charles is right. They were noisy. The machines depend on a vaccum pump attached to pull the tape in to a precision curved guide at the contact point with the heads, with the pump usually hidden behind the machine. You can see it in the attached photo from labguysworld.com (a great source on vintage machines). To thread the beast, you released the guide (the silver stub at the top of the photo) which is a view from above the head to open the path for threading and then closed it for record/play when you pulled the tape tight in the threading. I think the heads themselves may have been air bearings as I remember some air lines poking out from the head assembly. And that contact point made a distintive buzzing noise. Each head had its own electronic/mechanical properties. Some were factory new and some were refurbished by third-party companies like Merlin Engineering. As such, each recording/playback was dependent on the head used. If you played a tape on a different head, you could get some "banding" errors that the new head could not compensate for from the original. You can always spot a 2" tape from the "bands" of video that appear on the screen. About 16 or so on the average set. That comes from recording/playback/copying on different heads and different machines. Each head was a slim air-gap head which was subject to oxide shedding and would clog a head. That showed up on the screen as garbage on every fourth band. Remember that these were called quaduplex heads. You could try to fix this on the fly by spraying liquid Freon on the head and hope as the tape played. So much for the ozone layer. Broadcasters are to blame. When that did not work, you would gently touch the visible portion of the spinning head before the tape entered the guide with with your fingernail and try to grind out the clog. At the local station level, no one cared about head coordination with the original recording. It was too expensive. At the network level, records were kept to make sure that the head that was used to record a show was used to play it back for optimum playback. They had the money...then. Train fans will always say that steam locomotives are "living beings". Old quad machines are as close as we can get to that. And if you know where I can get a working RCA TR-600, send me a note. Dave A
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“Once you eliminate the impossible...whatever remains, no matter how improbable, must be the truth." Sherlock Holmes.
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#12
05-27-2009, 02:18 PM
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Quote:
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#13
05-27-2009, 02:49 PM
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Didn't they also re-use the tapes over & over back then as it was so expensive, which lead to stretching, breaking, drop-outs, etc, just like it does in audio tape ?
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Benevolent Despot
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#14
05-27-2009, 07:21 PM
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I worked in TV in Nashville TN from 1977 to 1984, and we had a pair of Ampex VR-2000 machines that were great. They would play anything, and they would lock on the signal faster than the two RCA VTR's that sat beside them.
They did have air bearings on the head assembly. I heard the high pitched squeal from the spinning heads so long that I can still hear the sound in my head today. I have a couple of old 3/4" U-Matic recordings that were taken from a 2" master. During the quiet parts of the recordings, the video head can be heard in the audio playback very faintly. When 1" came along, seems that the 2" machines just got pushed out of the way. I agree with others that 2" high band looked better than 1" type C ever could.
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#15
05-27-2009, 07:58 PM
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The quad machines started out needing the head that recorded a tape to go along with it to maintain usable playback. Over the years, the servos and time-base correctors improved such that interchange of tapes between machines became possible.
RCA's display at the New York World's fair in 1964-65 ullustrated the improvements. They recorded on one machine, then sent the tape through rollers for a several- second delay to be played back on another machine in black and white, then through more rollers to be played on a third machine in color. An explanation and pictures of the result that make up my avatar (unfortunately somewhat over-exposed, and rescued in Photoshop) are here: http://www.nywf64.com/rca04.shtml These were taken in June of 1965. At that time, the setup was working perfectly and no "banding" was visible. A better-exposed result is here: http://www.rhopkins.us/slides/disk01...s/6509b-21.htm
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