Ampex Nagra VPR-5

Note: Sadly all the photos referenced in this text are not available

This is a discussion (well more of a rambling essay actually) about a remarkable example of late 20th century technology, by Gino Mancini.

INTRODUCTION

I can still recall a certain slackness in my jaw as I first came across a picture of the VPR-5 in Nagra's Audio & Video product line catalogue of June 1988. I had been well bitten by the video equipment bug by then, and together with a good like-minded friend had already travelled to various far-flung corners of the UK in search of old (and thus very cheap) bits of video kit. I particularly remember enjoying a few glasses of good Port in quite a posh hotel in York while they closed the bar around us, having filled a van with ageing IVC equipment earlier in the day. Later I was quite glad they had grab rails along the corridor to our rooms, but I digress...

That Nagra catalogue rather changed my aspirational goalposts, and my mind wanders back to an even earlier time in the mid 1960's when having proudly just spent 30 shillings on a new stereo pickup cartridge (that's 1.50 in UK Pounds, and yes I am that old), I found out that an outfit called Ortofon made pickup cartridges at over ten times that, and you needed a special 9 quid transformer just to be able use it. So one learns that everything is relative, and It's a bit like that with this little Nagra video recorder, for when Kuldelski were building them you could get a very respectable domestic portable video setup for say £1,000, or you could re-mortgage your house (and sell the family) to get a VPR-5 for over thirty times that, and you still needed a camera and lens of matching quality at perhaps another twenty five thousand quid. Better sell the Porsche (and the BMW)...

Actually I didn't know when I was staring with lust at all those unattainable toys in Nagra's 1988 catalogue, that in fact their stunning miniature video recorder was already quite obsolete by then, and had been replaced by something much more convenient, of slightly lower quality and of vastly lower romance; Sony Betacam (but there again I don't get out much).

It's a bit like reel-to-reel and Compact Cassettes (remember those?) Valves verses Transistors and Betamax verses the dreaded VHS, all nearly forgotten now. And so perhaps with the long monologue that follows I am fighting (well perhaps just bleating) a sort of minor rear guard action for yet another nice bit of discarded technology. Perhaps as might a steam railway enthusiast have done thirty years ago when the nice Dr Beeching closed all those branch lines and brought in the Diesel-Electrics. Well I am a person of a certain age...

If you already know what a Nagra VPR-5 is, you won't need an amateur like me to tell you how nice it was, if you don't but you do like old or interesting technology I hope you find what follows to your taste. Sorry about the writing style but I'm no technical author and the whole thing started out as a sort of personal user-manual almost before the Internet was invented (and I can't face a complete re-write). I have though tried to include some nice pictures of the machine and other items mentioned as I go along.

The Ampex / Nagra VPR-5 C Format Video Tape Recorder

Fade up from black to perhaps six years later, times change and the BBC has moved on from reel-to-reel video recording on 1-Inch tape, and after quite a few telephone conversations, some racking of brains and a much lighter wallet, one of their Nagra VPR-5s is mine, all MINE!!

Ahem...

In 1994 I acquired an Ampex/Nagra VPR-5 portable 1 Inch C Format video recorder. I had been aware of this interesting machine for some time, though for obvious financial reasons it was to be a good few years before I was able to get my hands on the example you mostly see on these pages.

Since childhood I have been attracted to technical things and in later life collected various bits of unwanted old technology that included a few items of broadcast television equipment. Hi-Fi was also a consuming interest once, and while it seemed difficult enough to reproduce an audio frequency response of say 20 to 20 kHz with a good degree of 'fidelity', to do the same with a video bandwidth some 250 times wider seemed a very interesting proposition. Indeed because of the many technical challenges involved, broadcast television equipment was until recently forced to embrace many truly state-of-the-art engineering values. Though happily for the impecunious collector such as myself, the relentless changes in technology and format provided a happy hunting ground for the many interesting and often beautifully made things that were mostly just thrown away. It then became just a simple race between the land-fill site or one's own private 'museum' (and later perhaps back to the land fill site anyway).

And so for perhaps a 50th of what that little silver machine probably cost the BBC my VPR-5 became a valued item in a modest collection of other obsolete 'junk'. And over the decade that I have enjoyed this complex and glittering little box I have tried to learn about the machine's background and about the circumstances that brought it about. Unfortunately though with rather limited success so far, as while some technical documentation remains, virtually nothing seems extant regarding how or why this rather unique video recorder came into being in the first place. Michael Mailes's comments seems to suggests that Ampex refined an already built Nagra

prototype, but what caused Kudeleski to make such an extraordinary machine in the first place? We know that the Nagra SNN was built originally to record White House conversations (as stated elesware on the Web), and that they built other specialized surveillance recorders for the Americans as well as the Russians. Nagra also made all sorts of advanced instrumentation recorders as well, some of which one might find lurking inside a prototype missile or torpedo. Could therefore the VPR-5 have started out as part of some airborne military or scientific instrument package, that was later developed for broadcast TV use with the help of Ampex? Or did Nagra perhaps bite off more than they could chew and have to get Ampex to help them iron out the bugs? It is interesting to speculate how such a lavishly engineered and (outrageously?) costly device seemingly rather suddenly came on to the broadcast television market in the early 1980's. But if it was indeed a by product of the cold war we may never know the full story. However as this machine does seem to be so unusual, I thought it would be worth sharing what little I have found out about it.

VPR-5 BACKGROUND

Not being a professional but just interested, much of my knowledge of broadcast video equipment was obtained by studying various trade publications, in particular old copies of the S.M.P.T.E. Journal (very informative if you're into old film or video technology). Also with a bit of detective work, other moderately obscure sources such as American Cinematographer, Video, Televisual, and even early issues of Studio Sound were found to contain quite a lot of useful

information. I spent time at the libraries of University College London (adjacent to the Science Museum), Reading University, and at Surrey University in Guildford. Here I was able to do quite a bit of 'time travelling', and gleaned much interesting information about the development of television technology in general during the 1970's and 1980's. Interestingly though, my 'book learning' was no substitute to talking to those people who actually used or serviced these machines for a living, I am therefore most grateful to those knowledgeable and supportive professionals that I have been fortunate to come across at various times over the years, in particular Andy Shakeshaft, Joe Driver, Bob Smith and Tim Blackham.

I think it is fair to say that the Ampex/Nagra VPR-5 is regarded by those 'in the know' as something of a minor legend in it's own lifetime. During my research, a number of people I discussed the machine with knew of the existence of this little Swiss wonder though many had never actually seen one. One professional owner and user said (and this had already been demonstrated by Mr Mailes) that it was so tough that you could stand on it without causing it harm, which is quite true provided that the cover was locked-on. Though the reason why one would want to be able to do this might be open to conjecture. There was also a consensus that the VPR-5 recorded the best quality pictures of all the Ampex C Format video recorders. This was no small achievement considering its minuscule size in comparison to studio and the other so-called portable 1-Inch machines. A respected ex-BBC sound recordist while highly praising the Nagra's sophistication, did however make remarks to the effect that the machine could be rather tricky and unpredictable to work with, because 'you never knew what it was actually doing Gino'. Such are the differing perceptions between the knowledgeable professional user and the enthusiastic amateur collector. His opinion I well respect, and while the BBC also deemed it necessary to make one or two minor 'improvements' I am still though inclined to conclude that this little recorder is one of the finest examples of late 20th Century electromechanical engineering to be found anywhere. It is an object lesson in how form can follow function and not just mere fashion, it's not perfect of course but does certainly have a high 'wow factor'.

There are now doubt good if not better examples of this sort of uncompromising 'glittering engineering' to be found in things space or military. But the writer knows of no other real world piece of kit that directly compares to this complex little silver box. Of course there are other Nagra devices that are not too far off the mark, and I am thinking here in particular of their full-sized T-Audio tape recorder, or perhaps at the other end of the scale the tiny and watch-like SNseries of machines.

But to my mind the VPR-5 has to be a strong candidate for Nagra's masterpiece, and the more one delves into it's workings the more this impression is confirmed, as inside that CNC milled, anodized, aerospace alloy box, there is a feast of engineering and electronics to please the eye. Here exquisitely done mechanical features mingle with (once) state-of-the-art electronics. This is a real engineering tour-de-force quite unlike most anything else. Even compared to all other Nagra machines it is very apparent that this video recorder exists on a completely different level of achievement. It's rather as if Breguet himself decided to get into the broadcast equipment business. This little machine belongs in a museum as the definitive example of the heyday of Swiss electro-mechanical engineering. Never mind their watches, this really is an ingenious and well made object. (Well, reputedly one is already in The Metropolitan Museum of Modern Art.)

Described as a third generation C Format video recorder by William F. Carpenter's of Ampex, in his article published in the September 1983 issue of the S.M.P.T.E. Journal. The VPR-5 was probably engineered in the early 1980's by Kudelski S.A. of Switzerland and was refined by Ampex Corp. of America. These two companies were in their different ways THE most respected and experienced manufacturers of magnetic tape recording equipment. Ampex was at that time arguably the world leader in magnetic recording technology. They had after all developed audio tape recording from the captured war time German AEG Magnetophon equipment and had gone on to invent the Quadruplex television recorder, which was of course the first successful video tape format. Later Ampex would develop (though did not invent) far cheaper and more compact 1-Inch,

Omega-wrap helical-scan machines which would become known afterwards as the A Format. These machines became widely used in industrial and the then rather fashionable educational-TV environment. Ampex also produced the rather epic TM-7 self-lacing computer tape drives that became so popular as props in old science fiction films of the 1960's and 70's. Ampex also made high technology 'Winchester' disk drives, as well as fiendish ferrite-core computer memory plains. American technology and 'know how' ruled, but this was a while ago when computers were real computers and men were real men etc, etc.

In those days Kudelski was by contrast a much smaller Swiss company that produced the famous and highly regarded Nagra range of portable audio tape recorders. These rather unique looking machines were without parallel for quality-of-build, performance and reliability (the late version Stellavox recorders possibly excepted). Highly expensive, remarkably well engineered, but no 'nonsense', the Nagra (which means 'it will record' in Polish!), was for many years 'the' standard portable audio recorder as used by the film industry. As Francis Rumsey wrote in the November 1991 issue of Studio Sound:

' The Nagra 1/4 inch tape recorder has held its place firmly in the film industry as the machine of choice for portable high quality work in the most inhospitable conditions. This analog recorder has a reputation for reliability and solidity inspiring confidence in the film recordist for a number of years, although the weight of all this solidity has affected many a shoulder.'

In the late 1970's the co-developed Ampex / Sony 1-Inch C Format was becoming the de-facto broadcast videotape standard. While the media and the equipment was more compact and had a much lower cost of ownership than the older 2 inch Quadruplex system, the newer C Format machines still remained much too bulky for portable use. Ampex, Sony and Hitachi had already produced a few what might be described as transportable C Format recorders. But in reality one could hardly carry any of these bulky machines with ease or comfort, as they all weighed around 20kg and were the size of large suitcases. Bosch in Europe had developed what became known as the 'B' 1-Inch format slightly before Ampex's C system. This was a sort of cross between Quadruplex segmental recording and the single field 'slices' of Helical Scan. They seemed to have taken a Quadruplex head wheel, removed 3 of the video heads and mounted it horizontally in the transport, then wrapping the tape around this 'scanner' in an 'alpha wrap' rather like IVC used to do. The end result was a rather more compact transport that was said to produce better quality pictures than the Ampex system. But because the B Format still made a segmental recording the TV picture had to be 'assembled' electronically back together again, and therefore was not much of an advantage over Quadruplex for editing or slow motion playback. B Format did though have an advantage for portable use because the much smaller head drum allowed very compact and light-weight recorders (in reel-to-reel and even cassette form), that were much 'handier' than any

of the big C machines. Unfortunately the B Format while becoming popular in Europe did not compete successfully in the all important American market, because perhaps it wasn't invented there. This forced many broadcasters in the States to employ inferior quality though quite portable High-Band versions of Sony's U-Matic cassette system (though this was also not invented there) for electronic news gathering or electronic field production. However, it is well known that American broadcasters would and did use almost anything for news gathering, even VHS. It would have therefore seemed highly logical in the early 1980's, for the two major players in the professional video and portable audio recording business to team up and built a truly portable, truly broadcast video recorder, and so they did...

While wishing to learn more (do please do help if you know the full story) how this transatlantic collaboration came about and how things went during the gestation of this complex project, I now know that Ampex acted as consultants for video circuit refinement and that Kuldelski designed the mechanics, built and assembled the machine. Certainly there is nothing inside the recorder to indicate a source of manufacture other than Nagra, although one would expect items such as the video head tips would have been sourced from Ampex or their sub-contractors. (VPR-5 video heads are not interchangeable with Ampex equipment) As the writer has had some years peripheral experience with medical electronics product development, it is a wonder to him that this complicated creation actually got to see the light of day at all. Not surprising then that it was introduced into the marketplace too late, and remarkable that it actually worked as well as it did.

(Though one does have this nagging suspicion that the machine may have started out for use in a somewhat more exotic environment than the broadcast television industry...)

Ampex Corp. were to market and service the machine outside Switzerland. The term 'badge engineering' comes to mind, though perhaps a little unfairly. But Ampex's part numbering system for spares and accessories was to take precedence. Quite sensible perhaps considering the American company's market reputation and highly established customer base. The VPR-5 was though quite unlike any other Ampex product and indeed was quite unlike any other video or audio tape recorder. Lacking the usual vacuum-formed or moulded plastic casework, this machine was somewhat 'Swiss' in looks; lots of glittering silver-anodized machined alloy with an apparent manufacturing philosophy of 'let's not use plastic when we can CNC machine everything from solid chunks of aerospace alloy'. But as we will perhaps see, there were probably some perfectly valid reasons for this uncompromising approach.

The VPR-5 was introduced to television professionals at the 1982 International Broadcasting Convention at Brighton on the South Coast of England (of all places). But series production did not start until April of 1984. One wonders how the machine was received by its prospective customers apart from shock at the cost perhaps. Also by 1984 it was getting rather late in the life of the C Format, and was at a time when various 1/2 inch cassette-based 'tuned-up' domestic camcorder systems were starting to appear. Indeed the all conquering Sony Betacam format had already been shown to the industry in its first incarnation some 18 months before the announcement of VPR-5, and naturally these new cassette / component based video formats would have a significant negative impact on the success of the Nagra. In addition, the VPR-5's considerable cost even in comparison to other portable 1-Inch machines did no doubt limit its use for anything other than very top end broadcast E.N.G. or E.F.P. Surprisingly though a few corporate and industrial video producers also bought them. And even the odd 'pop star' was known to use VPR-5's while 'hanging out of helicopters and climbing mountains'. (Actually, a VPR-5 and Ikegami HL79d camera were rather lighter than an equivalent all-in-one Betacam 'camcorder' of those days - but the cameramen did not like being tied by a length of cable to the recorder's operator though.)

The publicity 'literature' for the introduction of the machine displayed a fairly depressing lack of imagination. The S.M.P.T.E. Journal copy and the first leaflet shows the usual pretty girl with a camera on one shoulder and the recorder draped over the other, just like it was some cheap amateur portable 'video' of the time. If one is charitable one might suppose that they wished to draw parallels with the convenience (such as it was then) of contemporary domestic equipment. But to the writer this approach just looks weak. Later they used un-captioned drawn images of planes, cameramen and operators, and even a 'cartoon' of an harassed jungle explorer carrying his VPR-5 while being pursued by irate spear throwing natives (!). This half-hearted rather muted approach in retrospect suggests that Ampex were a little ambivalent towards 'their' superb though alien product. They probably did appreciate the quite remarkable intellectual design and manufacturing achievement that this little box represented, trouble was it wasn't actually theirs (but there again neither were any of 'their' cameras).

At its introduction the VPR-5 was priced in the USA at 'about $45,000'. This significant amount of money can be placed in the context of other C Format machines such as the preceding VPR-80 at $36,000, or the slightly later and higher specified VPR-6 at $60,000. Both these machines though were very much larger studio 'work horses' that needed two strong people to lift them. While I am not sure of the exact Dollar / Pound exchange rate in those days or of the prevailing marketing strategy in the UK, it does however seem that a VPR-5 in basic trim was about 50,000 in modern GBP's. So it took very 'serious money' to kit oneself out with 'proper' broadcast television equipment in those days. In addition to the Nagra recorder one would also need a camera of comparable quality, say a 3 tube Ikegami HL79D at about £25,000, a Canon 13 to 1 zoom lens at say £6,000, and a studio playback machine at another 30 to £40,000 just to view the tape properly (all 1984 prices). Today it seems that things are much cheaper with the current confusing plethora of digital stuff. Ampex VPR-6 Studio Editing Video Recorder Ikegami HL79d Broadcast E.N.G. Television Camera

The VPR-5 together with the preceding Ampex VPR-20, the Sony BVH500, and a surprisingly sophisticated device produced (but possibly never sold in the UK) by Hitachi, seem to have been the only C Format portables ever made. They appeared perhaps between 1978 and 1984, but Nagra' machine was by a very large margin the smallest and lightest of them all. It was also the last portable C Format recorder introduced and was probably the most sophisticated, having in addition to its remarkably 'llipution' proportions a number of highly advanced operational features. Some of these in fact proved to be many years ahead of their time, and included an 'intelligent' power management system, extensive onboard self-diagnostics, and an elaborate automatic audio level control. But despite its small size, light weight and advanced features, it really was too late and (much) too expensive.

That it is of course no matter at this distance now that video recording itself has become just to do with the manipulation and storage of digital bits. To those who appreciate 'old fashioned' engineering values it is likely that we will not see the like of these machines again. The passing of professional reel-to- reel recorders (both for video and for audio), together with other now historical objects such as the mechanical chronometer and the precision 35 mm still-camera, mean that objects such as these will probably become the last monuments to the aesthetic and art of proper engineering; artefacts of a lost mechanical age. It is ironic that the new popular fashion for 'silver' home technology is in reality just the cheapest sprayed moulded plastic and folded tin, while the likes of Nagra's obsolete machines described here are quite simply the real thing. I suppose it is a by product of middle age that one becomes rather tired of constantly being told that what is new is better. As they used to say in London when I was young - do me a favour!

The prevailing conditions some 20 years ago must also have been rather depressing for Ampex and Nagra, as Sony were finding that their new Betacam camcorders, which were originally aimed at the rather poorer industrial users, were in fact rapidly gaining favour with serious broadcasters. Indeed this much more convenient though of slightly lower quality (SP version included) system, was to have a very significant impact on the long term American manufacture of broadcast television equipment in general. The technological high ground in broadcast video was, as with so many other things, being taken by those from the other side of the World. One may imagine that the vast amount of domestic product churned out from the Far East was and continues to finance lavish R&D into ever new generations of professional video stuff. Though for most everyone else this sort of funding could not be generated from the limited niche markets that many a western manufacturer was forced (by stock market enforced short-termism mostly) to retreat into. I suspect that inept management also had a significant part to play as well - but what's new eh?

VPR-5 DESCRIPTION

The machine featured here is an ex-BBC (of which there were 16) 'first version' with 'round' control buttons. The approximate date of manufacture is probably the 1st quarter of 1985. A second version of the machine with larger 'oblong buttons' and a number of minor soft and hardware enhancements was introduced perhaps a year or so later. I am advised that the control buttons were changed so that they could be operated by users with gloves on. The second version also has a pair of nice bright Red recording L.E.D's, which look like a pretty good idea...

The various features of the VPR-5 summarised as follows:

This type of machine is known as a direct colour recovery video recorder, and it records the whole bandwidth of a composite video signal onto the tape without the compromise of any form of hetrodyne colour-under (or digital for that matter) signal processing. When fitted with its standard cover and in its normal padded working bag, the VPR-5 could record for a nominal 20 minutes. The Ampex helical 196 magnetic tape it used, came wound on small and rather donut like plastic reels which were unique to the machine. These were supplied in either single or double cardboard boxes. Standard 1 Hour reels of 196 tape could also be fitted, though this required the machine's reel hubs to be rotated and locked into their outer positions. An optional weather-proof large 'Mickey Mouse' reel cover could also be fitted, but this was not needed if you were working inside and on a table perhaps. The small 20 minute VPR-5 reels could quite happily be accomodated for playback by both the VPR-80 and VPR-6 studio recorders (and I also expect by the VPR-3 as well).

The VPR-5's (PAL) frequency response was quoted as 'flat to 5Mhz', which in contrast to other analogue formats such as VHS, S-VHS, 8mm, Hi8, and U-Matic, gave a recorded resolution of at least 600 horizontal lines. The downside of the 1-Inch format was that you needed a direct colour recovery time base corrector (TBC) to get stable and 'broadcastable', pictures from the tape deck. At this cost level though it was normal for individual studio play back machines to be equipped with their own TBCs. (TBCs were once very costly and elaborate items. These days they supposedly can put them on a single chip.)

VPR-5 Open

Above is a view of the first version Nagra VPR-5 in the usual 20 minute configuration. This ex BBC Bristol machine seems to be slightly unusual in that its audio / time code record head has an elaborate brace and adjustment feature built under an enlarged rectangular head cover.

The one inch magnetic tape pays out from the right reel and is taken up by the left reel ('oxide in' wind only on this 'Mk 1' version). This is opposite to normal C Format machines.

The 3 LCD panels show Left to Right: VU or PPM audio record and limiting levels, machine status, tape and battery time left, or time code. The 4 small buttons under the right reel select: load-tape (this releases the parking brakes and moves back the pinch wheel clear of the capstan), enter cue 1 position, enter cue 2 position and enter edit mode. The row of toggle switches as part of the transport on the left of the machine enable (or lock out) audio channels 1 to 4 record, video record, and also select insert or assemble editing modes.

The image below shows the later 'Mk 2' version of the VPR-5, where Nagra have obviously made some small operational improvements. On the outside the various control buttons

have been made easier to use when wearing gloves. The record mode now has a nice bright red light, which also has another light by its side to alert the user of any fault conditions or servo problems. The power select and record level levers have been given locking 'buttons' to prevent inadvertent operation. The video record level is now adjustable from the outside, and the take up reel can be switched to wind oxide in or oxide out. Inside the machine, the software has been given some improved features. This second version of the machine seems to be very much an evolution of the machine, with both versions having a very similar look and feel.

VPR-5 Rear View

Rear view of the recorder.

There were 2 types of 'intelligent' NiCad battery packs that lock into the rectangular recess at the back of the machine - just under the deck plate. They are securely held in place by a simple peg on Left side and a spring-loaded plunger on the Right (this can just be seen in this image).

The Kevlar clad (yes, what they make bullet-proof vests from) 44 minute battery as is shown here did not project beyond the rear face of the machine, but the alloy cased 4Ah battery type NV-2ACC was a rather deeper and very much heavier unit.

(When the scanner is powered down, its high rotational inertia allows it to act as a generator to feed power back into the batteries.)

VPR-5 Leaflets

1st version Nagra VPR-5

Above is a view of the first version Nagra VPR-5 in the usual 20 minute configuration. (The 35mm film cassette - remember those? - is to the same approximate scale.) This ex BBC Bristol machine seems to be slightly unusual in that its audio / time code record head has an elaborate brace and adjustment feature built under an enlarged rectangular head cover.

The one inch magnetic tape pays out from the right reel and is taken up by the left reel ('oxide in' wind only on this 'Mk 1' version). This is opposite to normal C Format machines.

The 3 LCD panels show Left to Right: VU or PPM audio record and limiting levels, machine status, tape and battery time left, or time code. The 4 small buttons under the right reel select: load-tape (this releases the parking brakes and moves back the pinch wheel clear of the capstan), enter cue 1 position, enter cue 2 position and enter edit mode. The row of toggle switches as part of the transport on the left of the machine enable (or lock out) audio channels 1 to 4 record, video record, and also select insert or assemble editing modes.

The image below shows the later 'Mk 2' version of the VPR-5, where Nagra have obviously made some small operational improvements. On the outside the various control buttons have been made easier to use when wearing gloves. The record mode now has a nice bright red light, which also has another light by its side to alert the user of any fault conditions or servo problems. The power select and record level levers have been given locking 'buttons' to prevent inadvertent operation. The video record level is now adjustable from the outside, and the take up reel can be switched to wind oxide in or oxide out. Inside the machine, the software has been given some improved features. This second version of the machine seems to be very much an evolution of the machine, with both versions having a very similar look and feel.

Two views of the machine in 20 minute (above) and 1 hour (below) configurations. To change from the 20 minute mode (the standard cover fits over the machine in this mode) to a 1 hour recording mode is very simple: 1) Push the spring-loaded levers (rod-like projections from the hubs) towards the rear of the machine and hold. 2) Rotate the hubs to the back of the machine, and allow the levers to lock into place. Remember that DC motors, gearboxes and parking brakes are actually built into those hubs.

The lower image shows the 'delicate tracery' of the weight-saving as well as the simplicity of the screw-down reel holders. Naturally the disks that hold the reels on are machined-from-the-solid, though this time it IS plastic!

Colour Adapter

This photograph shows the colour stabilizer's DC to DC converter. (Note the spare resistors provided by Nagra.)

This 100kHz power converter provides plus and minus 12 V for the stabilizer circuitry as well as automaticaly preventing charging of the battery if primary cells are fitted. (Video processing electronics are on the other side.)

Nagra VPR-5 Front Close-Ups

In this particular machine set-up, the displays are (from left to right) showing:

Level meters display:

Off-tape video and RF levels.

Machine status display:

That the machine is externally powered (not from attached batteries), and is in play mode with locked servos.

The bargraphs are switched to show off-tape video and RF levels.

The continuous time code mode has been selected.

Record lock out is enabled.

Time code rather than tape position is being displayed.

There is an error condition (actualy low internal TC back-up battery),

The numeric display:

Current off-tape time code in minutes and seconds. (Hours and frames may also be displayed.)

The internal back-up battery is low.

Probably all a bit confusing when one was in a hurry stuck in a field somewhere, BUT all very advanced for 1983.

Camera Adapter

A typical VPR-5 camera interface (type NV-ICP).

Because each camera manufacturer had different connector and interconnection arrangements; Sony one type, Panasonic another,

Ikegami another (things never seem to change!), Nagra provided a rather nice universal way of connecting cameras to the VPR-5.

This interface consisted of a special electronics module on one end of the camera cable and the applicable camera connector on the other. The electronics module locked into a special mounting rail at the side of the recorder, and connetcted to the machine with a Canon D connector. Each interface module contained the special interface wiring for the camera such as tally arrangements and how the camera would start and stop the recorder, and these could be easily re-configured by changing internal DIP switch settings.

The HL79 interface shown in the above image has a rather nice 'made up' umbilical cable, which is highly flexible, contains a number of coaxial wires and also has an additional nylon rope for extra strength. Other camera interfaces might be fitted with 'standard' multiway camera cables.

The VPR-5 has both video and audio 'confidence playback' (real time off-tape monitoring of the recorded signal). This is in monochrome though, and is for use with an attached camera's B&W viewfinder to inform the cameraman that nothing 'nasty' is going on with the recording. A seperate colour adapter with comprehensive powering and nice internal battery charging facilities was available for playback in-the-field. This adapter was no replacement for a 'proper' time base corrector though, and only provides colour-under type performance (which equals about 250 line resolution with no drop-out compensation). The VPR-5 could of course be used with a studio TBC such as a TBC-6, and is equipped with advanced sync inputs and an off-tape RF output for dropout compensation. But, it was not made to be a broadcast palyback machine and its replay electronics do not have the performance of a 'full sized' studio machine.

The VPR-5 has a very comprehensive linear time code generator and reader, that can be referenced to external generators or to other similarly equipped recorders. This alows for multi-machine synchronized recording of a live event. The linear time code track is fitted in place of one of the 4 pre-wired audio channels (usually channel 4). Continuous or sequential time code recording is available. The machine's internal reader displays hours, minutes, seconds and frames on the right hand L.C.D. The machine also has a 'normal' digital tape counter driven from an optical encoder built into the takeup tension roller. (These articulated tension rollers can also pivot vertically by about 5 degrees.)

For editing, the built-in single machine edit controller provides frame-accurate insert and assembly edits of colour-framed video and the various audio channels. There are 18 individually controlled magnetic heads in this machine: 2 video, 8 audio (2 time code), 1 control track and 7 erase. Back-spaced edits are automatically carried out, and on entering the stop mode the machine sets up a 5 second preroll ready for the next assembly edit. When placed in edit mode, the feed spool hub 'web' can be used as a manual 'jog' control wheel for the simple setting of in and out edit points. Various edit preview and rehearse modes are also available to help with live recording situations. This expensive machine was after all intended to make (very) expensive television programmes day in, day out.

The video and audio interfacing is essentially modular in concept. Plug-in pre-configured 'personality modules' were available for various differing television camera types and makes. These interfaces consist of a small quick-release rail-mounted box, usually fitted with a captive multiway umbilical camera cable. Three types of audio input modules were also available to interface a pair of 48 Volt phantom powered capacitor microphones, a pair of moving coil microphones, or a pair of 600 ohm balanced line inputs.

A comprehensive microprocessor driven wired remote control and character generator was also an option. This provided in-the-viewfinder machine status and operating information. A basic module with advanced sync input, composite video input and output, and off-tape RF was available for video playback through a TBC. The machine can have up to 4 audio channels, though channel 3 or 4 was usually reserved for the linear time code track. As with the audio Nagras the audio recording system has a selectable turnover high pass filter with 'knee' frequencies, together with a two stage peak limiter.

Interestingly, an 'intelligent' automatic recording level control system (that seems to have been unique to this machine) was also provided. As the writer understands it, this system combines the limiter with a frequency shaped peak hold memory. This senses the amount of attenuation required based on the intensity of the incoming audio, its frequency spectra and the previous peak levels detected. It is designed that transient short-term high frequency sounds such as jangling

keys etc, will not upset the overall record gain settings. Apparently this system senses trends in wide-band audio levels and adjusts gains rather like a human operator might do. The expected prevailing sound intensity level (in dB's) may be set by the user on the calibrated front panel controls, and the real-time level of limiting is displayed on the left trailing ends of the LCD peak level bargraphs (peak levels on the right). These bargraphs themselves may also be internally set

to give either V.U. or P.P.M. ballistics. (P.P.M. is the default setting.)

Level Controls -should this be on right?

Because this is a portable and self-contained machine, the powering system is very flexible and also has some 'intelligence'. All internal power supplies are of an advanced switched-mode type and the CPU insures that only relevant circuitry is powered up for each specific operating mode.

The 4 DC electronically-comutated motors (Hall-effect sensing; no brushes to wear out) have their own individual highly efficient switched-mode powering systems.

The fast-charge NiCad battery system seems to have been at least 10 years ahead of its time. Two types of battery pack can quickly be attached or disengaged from the rear of the machine, and contain circuitry that provides data to the recorder's CPU on cell temperature, battery past discharge performance, current level of charge and previous run time. This means that the machine can calculate an accurate estimate of battery run-time left for any battery pack attached in whatever state of charge and in any mode of use. This information I have found to be accurate to the minute, and is displayed on the right hand LCD.

The separate charging systems consisted of a 6 battery pack slowish charger and a 2 battery pack fast charger. These use the battery's in-built cell temperature sensors to prevent overheating when on charge. If running from the mains PSU the recorder's in-built 'toping up' charger also updates the battery's state of charge data and increments the estimated run-time. An accurate estimate of tape remaining time is also available to the operator. This is calculated from take-up and supply reel rotational data when transporting tape, and has proved also accurate to the minute. When in fast wind mode, the machine automatically slows the tape down on nearing the end of the reel to avoid damaging the tape or the video heads as it comes off the spool. All not too bad for 20 plus year old technology?

The syscon CPU (1 MHz clock) performs a number of on-going house keeping tasks: checking general 'health' parameters, calculating battery remaining time, tape remaining time, and powering subsystems in the configuration relevant to the operating mode selected. The whole machine is very consistent in its actions and handling of tape, and is also extremely reactive to user commands. The various watchdog and self-diagnostics help to ensure the continuing 'good health' of the recorder. If any out-of-range conditions occur the CPU. will safely shut that section of the machine down and display an applicable error code on one of the LCD's. This is intended to

prevent any inclination to self-destruction. In addition, a knowledgeable user may access a fairly wide range of user defined options and self-diagnostic modes. The numeric key pad and the LCDs may be used as a simple 'terminal' to communicate directly with the syscon and time code CPUs. The user may select various day-to-day functions, such as setting time code user-bits or the various display modes, or can delve much deeper into the machine's operating system. By keying in various coded instructions, most subsystems may be individually evaluated for their current state of health. Therefore a knowledgeable user may quickly ascertain his VPR-5's overall condition, including (with the 'Mk2 version) the machine's power on time and the video head running time. However information is lost if the Lithium backup cells go flat, and despite all this cleverness I know of one case of near total self-destruction when a machine caught fire internally. This underlines the sobering fact that (even Nagra) high current switch-mode power supplies and DC motor drivers can sometimes 'let go' in dramatic ways. These many advanced features might though be expected from a professional broadcast tool, but it is the physical design and construction of the VPR-5 that I think makes this 1980's artifact even

more special. Because inside that beautifully sculpted exterior there is quite a lot to appreciate. Seemingly free of sane engineering values, Kudelski produced a remarkable statement in aircraft alloy and surface-mount electronics.

To minimize weight 'Aerospace design and machining techniques' were used. This is not mere advertising hype, as the VPR-5 shows mechanical design and fabrication philosophies that are to be found in any item of state-of-the-art avionic or space exploration equipment of the time. To save weight, most of the machine's mass - perhaps over 90% in some places, was meticulously C.N.C. machined away. The resulting high strength lightweight components were then assembled with considerable skill and ingenuity. Fortunately all this effort was eventually recognized by the industry, as Ampex applied for and was granted an 'Emmy' for their (and Nagra's) work of art.

Why to the writer all this fine precision and machined alloy seems so satisfying and pleasing to the eye is not known. Another aspect of attraction is perhaps that open reel tape machines perform their business in public, and one wonders if the rotation of the reels and the movement of tape might perhaps cause subtle positive psychological effects. At any rate, in contrast to 'inanimate' machines where the business of recording is performed 'secretly', all reel-to-reel equipment has a certain life and presence when 'doing its thing'. And this is especially true of the VPR-5 when that big 5 Inch head drum spins up to its 3,000 rpm running speed, taking 1 second and some 16 Amps from the battery to do so.

Enough of the metaphysics though. This machine was carved from solid metal for entirely pragmatic reasons, because (of course) the chosen raw material for its structure dictated this particular way of working. The aluminium alloy used is the increasingly well known 'aerospace grade' type 7075-T6. This artificially aged material approaches the tensile strength of steel and is unaffected by cold working (machining), it cost though about 4 times the price of less exotic aluminium alloys. It is also quite unsuitable for casting or welding, but again, no cast light-alloy structure could approach the strength of a machined-from-solid anealed plate of the stuff. Where joins had to be made they used stainless steel screws, rivets, or a very nice metal-loaded epoxy glue. Machined 7075, rivets and nice glue was by the way what the Saturn 5 'Apollo Moon

Rocket' boosters, and probably many ICBMs were mostly made out of.

All the internal and external surfaces of this machine are anodized to protect against corrosion and to increase strength. Though how they got that perfect graining in all those various hidden recesses is a mystery. This is probably a by product of the anodising process that highlights the grain of the metal. All ledgending is in anodic print, so it won't wear off. One could believe that this machine was the very height of what is known in management speak as 'best practice', though the extremes that Nagra went to in some instances does seem rather too much of an overkill sometimes.

20 Minute Reel Configuration

Wired Remote Control

Take for example the audio and video interface modules. These light weight little boxes that lock so easily into their respective locations on each side of the machine have cases that seem to be machined from solid blocks of alloy. Indeed it seems that perhaps 90% of material has been removed to leave just the thin outer skin and some narrow mounting flanges. Could these not have been cast in aluminium, or even moulded in a suitable plastic? Perhaps Nagra got a good deal on all that swarf. They do seem quite tough and look very nice though...

The front panel is also machined from the solid, and possibly represents less than 20% of the original material present. In fact the inside surface of this panel is a more complex milled surface than the outside. Each control button is a solid CNC carved and colour-anodized component retained in position by an individual leaf return-spring. To help prevent accidental damage and inadvertent operation, the controls and buttons are all well recessed into the front panel. The heads of many of the exterior fixing screws are fitted with small Nitrile O rings, presumably for retention as well as water proofing.

The locking lid assembly seems to be a rather complicated paradox. The top surface is another machined-from-the-solid alloy plate with three O ring-sealed polycarbonate (?) viewing windows. Underneath this lid are undercut girder-like strengthening features ('intrgrally machined T stifners'). The lid contains a marvellous over-center cable locking system, operated by a beautifully milled recessed stainless steel and alloy folding handle. (I counted over 150 separate components in this lid.) The top plate is bonded to the riveted thin-alloy side walls with a metal- loaded epoxy resin, and the whole thing locks down and seals to the recorder's deck plate with 5 individual spring-loaded latches. A quite remarkable structure, probably proof against the elements, and you can stand on it (as Mr. Willetts has demonstrated). But would not a transparent vacuum-formed plastic cover as used on their audio machines have been a rather more sensible approach? Well apprently not for heat sinking reasons I am advised, though how you get inside this wonderful lid if that complex locking system should fail looks an interesting challenge. Ah, but (of course) there is a proceedure for doing this described in one of the manuals.

After removing the 3 screws retaining the central boss of the video head drum and lifting off the thin cover plate, you will find that this particular scanner is rather different. In place of the usual fairly simple machined light-alloy item, you will find a delicately lightened, triangulated and undercut cylinder of aircraft alloy with a special hard wear-resistant coating. Mounted within this drum are 3 individually user-replaceable video heads (record, play and erase), 3 'dummy' video sync heads, as well as the video drive amplifier, video playback pre-amplifier, and video erase oscillator. Again, the complex 'star of David' form of this head drum suggests CNC machining-from-the-solid. The flat drum servo-motor is actually built inside the lower half of this scanner assembly and like the rest of the motors in this recorder uses powerful (and costly) rare-earth magnets.

By carefully releasing the 7 O ring-sealed screws retaining the top plate of the recorder, you are able to lift the transport and the whole upper surface of the machine upwards on two small hinges. This surface is made up of two separate machined plates one within the other; the inner tape transport chassis itself and the surrounding top cover of the electronic package, there is a small gap between them. The transport chassis is supported within the surrounding cover plate by 3 strategically placed short stainless steel pins. This I imagine defines the external stresses placed on this critical component. The top cover is sealed onto the rest of the machine by a large elastomer O ring. Surprisingly few mechanical components project below the lower surface of the transport. The scanner, capstan and reel motors are either situated within the deck assembly itself, or are built into their own respective areas above the transport. Normally reel and scanner motors are quite bulky items especially on 1 Inch tape machines. But in this recorder the reel motors together with their reduction drives and parking brakes are actually built inside the NAB-type reel hubs (US patent 4,542,663 filed Sept 15 1983). What makes this all the more impressive is that despite their minimal volume, these complex 'powered hubs' have no trouble at all in driving the big and quite massive 9 Inch, 1 hour reels at high speeds. The reel motor commutation and drive electronics are built into the machine's substantial base plate.

Also provided within the machine, (as with most Nagra products) is a small plastic tube of basic spare parts. How thoughtful. The whole of the interior of the VPR-5 is virtually filled with multi-layer surface-mount printed circuit boards, together with a miniature wiring loom. The electronics are in roughly four layers;

1) Fixed under the transport (audio and video record and replay).

2) Above the middle central dividing plate (audio AGC, time code, system control).

3) Below the central plate (reel, capstan and scanner digital servos).

4) Built into the upper surface of the base plate (PSU, bus, reel, capstan and scanner commutation).

There are 17 main circuit boards and another 20 smaller sub-boards, and all of these are interconnected by means of a very nicely done avionics style wiring loom which employs a mixture of flat miniature 'headers' and hand-soldered lay-on joints. The loom's connections number over 1,000, and each of the 500 wires is marked at both ends with various references and even the volts carried. There are over 435 transistors and 285 surface-mount I.C.s in this beast, together with a further circuit board and 15 I.C.s in each battery pack.

The main electronics package is divided horizontally by a milled and anodized alloy plate. This is bonded to the machine's thin wrapped sheet alloy side wall by metal-loaded epoxy cement. This dividing plate one assumes is for both structural and screening purposes. The top electronics compartment situated directly under the transport contains the audio record-replay, video record-replay, time code, DC power distribution, and syscon printed circuit boards. The lower compartment under the dividing plate, contains the electrically more noisy systems of the switching power supplies, motor commutation, digital bus, and reel, capstan and scanner servo system power drivers. All these surface-mount circuit boards are 'bolted' to the various surfaces with the usual white Nagra slotted plastic 'nuts'.

The base plate itself is another example of the interesting manufacturing values employed in this machine. No simple plate this, but a complicated nest and heat sink for all the power circuitry built onto its inner surface. Around the periphery of this plate is another large elastomer O ring seal, and nesting within are 13 circuit boards, a selection of torridial inductors and power transformers together with 46 TO220/MJE packaged power transistors and assorted MOSFETS.

The special Lithium 6 Volt battery pack for time code and syscon backup also lives here. The circuitry is very neat and compact, though must also have been a nightmare if any dimensionally-critical component became un-available. The transport surround and base plate form a stressed box section structure for the machine and must have the various fixing screws tightened and released in an incremental way, rather like cylinder head bolts of a car engine. In fact when tightened up, the whole machine becomes a very tough metal sandwich. (I wouldn't like to drop it though!)

On the under surface of the machine there are no simple mounting feet as such, but an undercut rectangular recess at each corner. These are designed to accept various special mounting fixtures. For field use, the padded working case has 2 alloy fixing strips that turn-lock into these recesses to hold the machine securely. Or one can by similar means lock the machine into a special back-pack harness frame. In a mobile 'scanner', in the studio (or aircraft?), one might be expected to fix the machine on to its own special anti-vibration table mounting plate, or slot the machine into a special rack-mount box. (The recorder slides in sideways on rails.) Naturally, the machine's carrying strap which is rather like part of a military jet's seat belt harness, has its own special spring-loaded, machined-from-the-solid-and-anodized fixing locks. (But what else?)

My conclusion is that the Ampex / Nagra VPR-5 has to be one of the finest examples of electro-mechanical design there is. It has a purity of form that reflects the considerable intellectual achievement invested in it. Highly expensive and exotic when new and now obsolete and nearly forgotten, it does though remain a very pleasing and wonderfully tactile sculpture in anodized alloy. (Actually it would probably look quite at home in a modern minimalist apartment!) Vastly in advance of their audio recorders of the time it is a bit of a mystery how it came to be made at all and remains an anachronistic statement of true engineering values, made all the more impressive for the quality of results that it is still quite capable of. Described by one owner 'as a work of art', and another as 'the eighth wonder of the World', it was rendered too soon un-viable by unfavorable external circumstances. Deserving perhaps to have been more long lived than it was, it is now rare and of currently moderate value.

You don't have to have any interest in old television kit to appreciate or perhaps desire to own one of these beautiful little boxes, just have some seriously good taste.

Bravo Nagra and Ampex! - and my compliments to the reader having got this far...

The text and pictures on this site (excepting the leaflets, and Mr Marriott's images) are my copyright. If you make use of them in any way, the decent thing at least to do is to acknowledge the fact.

Gino Mancini, May 2005.

THANKS TO:

Ray Barron

Tim and Will Blackham

William F. Carpenter

Bob Craige

Joe Driver

Bob Marriott

Andy Shakeshaft

Robert Smith

Michael Willett

SOURCES:

VPR-5 Service Manuals, 1984 edition.

VPR-5 Product Description Vo.1, March 1986.

VPR-5 1st and 2nd version sales leaflets.

Ampex colour stabilizer manual 1984.

Nagra General Catalogue, 1990.

Various copies of 1980's TELEVISUAL magazine (University

of Reading - Bulmershe Court).

Various copies of VIDEO magazine, 1978 - 82 (University of

Surrey)

STUDIO SOUND magazine 'Video' issue 1972.

VIDEO PRODUCTION TECHNIQUES

S.M.P.T.E. JOURNAL 1976 - 88 (University of Surrey and

Imperial College London).

AMERICAN CINEMATOGRAPHER magazine 1980 - 90

(University of Reading - Bulmershe Court).

VIDEO RECORDING, Ampex 1986 (As loaned by Andy

Shakeshaft).

VPR-5 with Remote Control module fitted

A view of the right side of the machine with the remote control / character generator module locked in place. The Canon D sockets (red multipins) are used typically to connect accessories to the machine such as the colour adaptor, and they also provide DC power, audio and video outputs.

(Nagra thoughtfully provide connector pin input and output information on most of their products.)

Note: in most operating configurations the VPR-5 requires special linked 'dummy plugs' to be inserted into the D sockets. (Otherwise there may be no video or sound.)

VPR-5 Battery Mount

Rear view of the recorder.

There were 2 types of 'intelligent' NiCad battery packs that lock into the rectangular recess at the back of the machine - just under the deck plate. They are securely held in place by a simple peg on Left side and a spring-loaded plunger on the Right (this can just be seen in this image).

The Kevlar clad (yes, what they make bullet-proof vests from) 44 minute battery as is shown here did not project beyond the rear face of the machine, but the alloy cased 4Ah battery type NV-2ACC was a rather deeper and very much heavier unit.

(When the scanner is powered down, its high rotational inertia allows it to act as a generator to feed power back into the batteries.)

The supply and take-up tension roller assemblies are as usual beautifully done. Both upper brackets are machined solid blocks of alloy (the take-up bracket has been dismounted and is shown below), and they strongly locate the upper ball bearings of the rollers. The finish on these fixed tape rollers seems to be a form of hard anodize that has a translucent almost glassy appearance. I am not sure why there are two sets of shallow groves cut into them, though one often finds grooved rollers or pinch wheels on wide tape machines, to even tape stresses and help disperse the air in fast wind modes perhaps? The spring arm mounted tension rollers on the VPR-5 have different finishes; the supply roller is smooth and almost glassy, while the take-up roller has shallow grooves.

The supply tension roller in the above image looks perhaps to be slightly at an odd angle to the darker fixed roller, and shows quite nicely that these supply and take-up tension rollers do rotate vertically plus or minus a couple of degrees about a pivot that is placed halfway up inside the roller itself. The left hand take-up tension roller is even more impressive as it also contains a miniature optical encoder for the tape counter. One assumes that these swing-arm tension sensing rollers are made to pivot so that they can 'follow' the precisely set fixed rollers and always present a parallel surface to the tape. (The actual measuring is done under the deck by a small wedge-shaped arc of copper PCB track varying the inductive coupling of a transformer driven by a high frequency signal.)

One of the many nice features of this machine (below) are these rather fine base plate spacers. In addition to 5 of the sealed set screws shown above, the base plate is secured to the strong central plate the machine by another 5 longer screws, of which 4 pass through one of these spacers at each corner. The little 'archway' is just to save weight, and notice that the half nuts are

fixed to the stainless steel threaded inserts without washers. Extreme weight saving?

This is a view of the longitudinal head area of the VPR-5, looking from the front of the machine. The protective metal cover has been removed and we may see (from Right to Left) the stacked audio / time code erase head and the record and replay magnetic head assemblies.

On this particular machine we can also see what seems to be an unusual audio / time code recording head steady and phase adjustment device. This consists of a beautifully finished bracket fixed around the top capstan bearing area and a machined rectangular framework surrounding the erase and record heads. It is not known if this feature and this machine's unusual head cover were an early modification made for the BBC, or were perhaps found to be not needed in subsequent machines.

VPR-5 lower compartment opened.

A view of the lower electronics compartment with the base plate lowered for access.

The circuits shown on the vertical section of the machine in this picture are from left to right; digital bus control, capstan and reel motor servo system (patented under US No. 4,513,229 filed 15th September 1983), and the small board to the right of these is the scanner motor servo system.

The circuits on the base plate of the machine are (L to R), more bus control electronics, the main switched-mode power supply, scanner, capstan and reel motor switched-mode drivers. The recorder's thick base plate acts as a heat sink for all this power conversion circuitry built into it