dela

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About dela

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  • Location
    Copenhagen
  • Interested in Sound for Picture
    Yes
  • About
    I have been working with film post production for 12 years; I am now primarily working with TV (on a danish national broadcaster, as well as being involved i film projects. I am quite fascinated by Nagra recorders and everything connected with them.

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  1. Regarding the bag, I have only seen two types: The original Kudelski-bag, which is fine except the zippers (as you found out) and a custom made bag, that Radio Denmark used in some cases. It was dark brown leather and much more sturdy that the beige original, but I have only seen one of them in real life (I have one...). It was actually distributed by the father of one of my collegues, but they are probably now long gone... So I would go with replacing the zippers on the original bag.
  2. I can imagine that it would take some persuasion to make a customer change to a new recorder that forces him/her to change the entire range of accessories, and at the same time is limited to 5" reels. I don´t know the price point of the IS, but my guess is that it would be in the same rage af the 4.2, perhaps a little lower, but not much. So yes, a niche product more than a universal tool... I have been stacking up the machines today to show the front plates (and ears) of the different models. As you can imagine there is not much difference, but there are some. Mainly they are: - Right ear: The recorders prepared for pilot system has a pilot signal input socket (as the pilot board is missing, it doesn´t do anything) - The pilot indicator: Same as above - The ALC switch: Interestingly enough the very neat mechanical parts are installed in the ALC-prepared recorders, but the two-way knob is replaced by a blocking cap that prevents you from operating the switch. As with the pilot-prepared machines, you could modify the machine quite easily by replacing the ref. generator board with a board containing both the ALC and the ref. gen. On the "group photo" of the IS recorders, the different types are: Left side: Top: IS-DT Middle + bottom: IS-D Right side: Top + bottom: IS-TLSP Middle: IS-DE After I took the pictures and wrote the list yesterday I found a Kudelski brochure listing the different subtypes, and most of mine are listed there (the TLSP is missing), and I can see that the difference between DE and DT is that the DT is (as the only non-sync) a two-speed recorder, the other ones are single speed. Not the world most significant fact, but still a difference . And speaking of insignificant but still a bit intriguing details: I dug a bit in the service manual, and in there the unmounted connector in the cabinet cut-out is marked as for "accessories". It is placed on the reel motor control board, and the control bus signals for the tape transport (in- and outputs) are led to the connector pins (along with a power output). This just about confirms my thought that a large reel adaptor was planned, but never materialised. Sadly enough... For illustration I have enclosed a picture of the IS compared to its smaller and larger siblings. They say images don´t lie but, as JBond writes, when you see the IS in real life, the IS seems much smaller that the (in comparison) bulky and clumsy-looking 4.2. The 4.2 in the picture is, by the way, a work in progress: The electronics had been severely water damaged (the transistors just fell off like ripe fruit when you touched them), and I had actually given it up. But stubborn as I (sometimes) am, I have been nurturing back to near health, which is a great joy, remembering how it looked before...
  3. Another long weekend at work, so I might as well fulfill JBonds wish for descriptions of a (small) variety of Nagra IS models. Mainly there are three versions of the IS: The non-pilot version, the pilot version and an intermediate model, which is non-pilot but prepared for pilot head and circuitry. As my machines are primarily radio recorders, they are all non-sync versions; I hope that I will eventually get a sync-version also... The versions I have are: IS-TLSP (2 P48 mic.inputs, prepared for pilot i.e. with pilot indicator installed) IS-D (Only dynamic mic. inputs, no pilot indicator) IS-DT (1 x P48, 1 dynamic mic inputs), no pilot indicator) IS-DE (2 P48 mic. inputs) The different types are almost identical, except the described differences. The IS-TLSP is also prepared for ALC (Automatic Level Control), shown by the (disabled) ALC control. Age-wise there are also some variations, just like on the larger types: Older recorders have all-steel tape guides, newer types has all-ruby guides; I guess that the even newer ruby/ceramics guides came later than the IS. On some of the machines a playback head shield is fitted, on others there is no shield. On the IS-TLSP the left tape roller has a rotating plastic part, where the D-types has a massive aluminium roller. All in all: Small and not very significant changes, but it still shows, that is was a model with a very long active career. I have attached pictures of IS recorders, and (I can´t help it, I am a technician) a couple of pictures of the inside of the IS. As you can see the mechanical and electrical build quality is the same as the larger types, so the IS is by no means a discount product (like the Nagra E). It is tightly packed, but still very serviceable, and high quality parts are (mostly) used. Unfortunately the rotary switches are not really great, and I have had to spend some time getting them to work properly, but apart from that there has been very few age-related problems. All my IS recorders has female mic. input "ears", but in some cases male XLR input connectors were used. It might be that there is a swiss parallel universe where microphone cables end in female XLR connectors but I have yet to meet one... Hidden underneath the battery compartment is a cut-out in the cabinet, usually covered by a metal plate. On one recorder it was covered with a sticker labeled "Only for use with large reel adapter", which is quite intrigueing, because I have never seen or seen any reference to such a "IS-QGB" anywhere. Perhaps they feared that a large rell-capable IS would cannibalize their market and dropped it before even releasing it. But it would have been a great addition. I can´t help thinking that the IS partly was an attempt to make a design upgrade to the Nagra series, and if it had been sufficiently well received, the changes would have been introduced in the IV/4.2 series (or rather: A successor to it). As it happened, people preferred the simpler 1-motor design, probably because it was a very stable, time proven design, and thus the brilliant IS solutions were never used on other recorders. Nikon made a similar gamble when they introduced the electronic F3 to replace the tank-like F2; users were nervous that it would be unstable and ureliable, and moaned a bit about that. It turned out that the F3 was a brilliant camera and became an instant classic...
  4. Rachel: Congratulations with the IS; it is a really nice little recorder. Small, but in every aspect still a Nagra. In Denmark (where I live) it was almost exclusively used for radio, so it is rarely seen in the pilot version here. For film work the 5" reel limitation was a problem, but many a Radio Denmark journalist loved not having to carry a IV/4.2 around. I can also imagine a journalist would hate having to transcribe an interview with the rudimentary tape winding system on the IV/4.2; here the IS motor controlled transport really shows its strength. I have been looking in my manual archive, and I have found an IS user manual, unfortunately only in german. I have an english paper version, that I can scan at work this weekend, if your german isn´t up to scratch. I also have a service manual, and that is in english. If you send me an email address, I will send them to you. They are quite informative, as you would expect from a swiss company.. The one problem that I can see with the IS is that (mechanical) servicing is quite a bit more complicated that on the larger recorders. F.ex. if you want to change the reel motor assembly, you need a special measuring gauge to adjust the position very precisely, and even with that it should not be quite time consuming. On the larger machines, the tape transport was built around a very sturdy steel plate, so virtually no mechanical adjustments of the position was necessary. The small, all-aluminum chassis came at a price... But still a marvellous little recorder; I have 6 of them in various versions, and I love them all. The cuteness-factor of the SN is undeniably larger, but it is a bit like choosing one of your children over the other (but, having just about all available types on the shelf, I can enjoy not having to choose). And by the way: I couldn't´resist buying the 4.2 IRT, so I will get back with some more info after I pick it up next week. I haven´t heard from Institut für Rundfunk Technik, so I will probably have to figure it out myself how to use the TC system. Fortunalely I have salvaged a scrapped Alpemann & Velte TC generator/reader, som I am prepared for everything. And looking forward to it.
  5. I had actually thought about the Neil Stone modification; it seems to be the same principle as in the IRT 4.2... I have just had a 13 hours watch at the TV station I am working on, so I have had a bit of time to look for more clues. And in another forum (Gearslutz), I found a reference to a 4.2 modified by IRT, which I completely had forgotten stands for Institut für Rundfunktechnik. A bit silly, as I am regularly receiving updates from them after buying some very expensive software from IRT. It seems that they were equally inventive back in the days of the 4.2, because they made a modification with an extra board that generated a short TC burst when going into record. You could then jam sync a TC generator when transferring it back home. This sounds reasonable, as the 4.2 IRT currently up for sale is from WDR (West Deutsche Rundfunk). Judging by the details on the IRT machines (ruby guides, tape counter roller) it seems like they were modified somewhat late in the 4.2 life time cycle. So it seems that it is not a real Kudelski mod, but a very capable one, that was made on quite a few machines. But still nowhere near the sheer brilliancy of Harvey Warnkes superb TC mod. I know that I will get one eventually; it would be great to add that to the collection. And thank you for you comments; I imagined that I would get some very insightful answers.
  6. I know that I should probably start a new thread about this, but nonetheless I have something that I would love to find out more about... Once in a while I have come across eBay listings of the Nagra 4.2 IRT, which is a bit of a mystery to me. When you look at a 4.2 IRT the only immediately unusual thing about it is that the function switch and knobs are green in stead of the usual black. But another significant feature is that it has stereo heads in stead of the usual mono heads. Yet another indication that something is different is a little indicator light near the function switch marked "Zeitcode". So I guess that it is a 4.2 modified to record and playback LTC, and since the LTC is put on the middle track, the playback head gap must not cover this track, and thus they use a stereo head (for a pilot/TC IV-S, with broad guard band) with the two tracks paralleled. But that is just my assumption; I have seen them both with a normal crystal generator board and an unknown, more advanced board installed on top of the battery compartment. Does anybody know if the 4.2 IRT is an "original" Kudelski version or a third party mod? Or just anything at all?I am really curious...
  7. For that price you at least could expect a consistent/meaningful color coding? Or perhaps it would be interesting to have an expensive cable enabling you to hear R-L in Right channel and silence in Left channel?
  8. Yes, the Nagras were very kind to the batteries... The IV-S used app. 270 mA in record mode, 110 mA in Test mode. I just checked the specs of the Portadat (just to pick an older DAT machine), and by a quick calculation it seems that it used 1-1.5 A in Record mode. And on top of that, it used the horrible NiMh-type battery packs (2 hours recording, then 2 hours charging. The first 6 months...). Even the Nagra D actually ran on D size cells (although rechargeable, in a PAGMASTER 90 battery). But it was without mercy: If the internal battery is completely discharged, the recorder won´t start, even with the charger connected. It only charges the battery properly when it is switched on, in Off-position it just trickle charges with app. 50 mA, and gives a strange Catch 22-situation. So be prepared to wait for some hours before start working this day. I have an old PAG-charger to jump start the battery when I turn the D´s on once in a while. Just to see them work; they are things of great beauty...
  9. The Nagra IV-SJ was intended as an instrumentation recorder for recording measurements (vibration, sound, actually any varying signals). There was a market for that, as there were no digital data loggers available yet. That is why the SJ had some additional features compared to the normal IV-S, mainly the possibility of real calibration (giving repeatability of measurements, as there were stepped attenuators in stead of potentiometers) and a very wide frequency range. However this wide frequency range came at a cost: F.ex. noise, dynamic range and distortion values were not as good as the standard version. It also lacked normal audio input connectors; it had LEMO input connectors, compatible with Brüel and Kjaer measurement microphones, which are very different from normal audio microphones. Thus there were no (known) audio-related modifications like the Warnke TC system, as the SJ was not used for film, TV or any audio purposes. But I have seen several strange Frankenstein-recorders, where custom built special purpose recorders were built around a Nagra chassis (f.ex. by Schlumberger). Some fine, some quite bizarre but all very different from the original Nagras... However nice the IV-SJ was, it was not the perfect instrumentation recorder. "Real" instrumentation recorders (as the Nagra TI, various Brüel an Kjaer recorders etc.) were FM recorders, where the input signals modulated a signal, that was recorded. This made it possible to record DC signals and other very slowly varying signals, whereas the SJ had a minimum frequency of app. 25 Hz. But for audio range measurements and on location data recording it was great, as almost all other instrumentation recorders were quite bulky.
  10. Just a quick note about the Nagra ID card: Nowadays Kudelski SA´s main business is data security products and, mainly, encryption for various types of broadcast. The audio section (Audio Technology Switzerland SA) is split completely from the mother company (Kudelski Group). So the Nagra ID card is completely in line with the recent company profile, which is unfortunately not so intriguing as the original profile. But seemingly much more commercially successful... Still, it is not seen every day that a high tech company was started 65 years ago and is still successful. So I guess that if they are still into covert recording, it will probably have been as virtualised as their software portfolio. And infinitely more boring...
  11. @Micke: Be aware that Nagras are hugely addictive. Ten years ago I had 1, five years later I had 4 and now I have 21. And there is still room for more...
  12. Just a quick note on the hole/connector on the serial number end of the SN: It is the input connector for external speed control of the SN. It is primarily used by the LPS synchronizer, and it seems like a bit of an afterthought. Electronically it is also a bit awkward: The unshielded input goes directly to the base of a transistor, without any protection. Not every Kudelski circuit design is a work of art...
  13. Yes, it is a fine collection of machinery. And there is no need for apologizing for showing non-nagra things; I can see a lot of machines that are equally or more interesting than the Nagras (and that is not an easy thing for me to say). I still regret that I didn´t do more to get the Perfection PM6E offered on eBay last year; I can see that you have one...
  14. You have come to just the right place... Strictly speaking it is not a SNST, actually it is probably/certainly not even a Nagra. But a really good copy, and judging from the exterior not made to be cheaper than the original. Probably the export of the Nagra products are more or less embargoed, and the different russian secret services were not interested in Kudelski SA knowing what equipment was used in the Soviet Union (Kudelski SA had tight connections to the US secret services). In that case a more "acceptable" solution was to copy, even though the copy might be more expensive than the real thing. I would love to see some pictures of the interior; they might have had a harder time figuring that out. A "fake", but actually a somewhat more interesting collectors item than the real SNST... Okay, I might have been a bit optimistic about the performance: http://www.tapeheads.net/showthread.php?t=50789
  15. On the Nagra 4.2 (and also the IV-L in many cases) the crystal generator was internally mounted, so that if you fitted a little plugged cap in the pilot input connector, the generator signal was looped back to the pilot input. At the time of the design of the SN both crystals and standard integrated circuits were too big to fit into the SN body, so that it was necessary with an external generator. The standard SXG generator is pretty much as small as it was possible at the time, finding space for that on the inside of the SN would make it larger. And since most users would use it without crystal sync, it would have been impractical to make the body more bulky. I am sorry for any mistakes about the pilot system; I have worked in film post after the main Nagra-era. So my knowledge about it comes mainly from written sources, handling my own Nagras and studying schematics. So comments and corrections are welcomed...