David Waelder

Members
  • Content count

    1,290
  • Joined

  • Last visited

About David Waelder

  • Rank
    Hero Member
  • Birthday January 1

Contact Methods

  • Website URL
    http://www.productionrecording.com

Profile Information

  • Location
    Los Angeles

Recent Profile Visitors

2,695 profile views
  1. And, at the time Hafflex introduced his meter, Arriflex was still marketing a control unit for the 16BL that used a tuning fork timer similar to the technology of Accutron watches. But I think crystal controls for the Arri were already available from others. (Now a picture of that control unit would be a challenging item to identify.) David
  2. Sure. It's a "Piece Of Mind" meter. I think the fellow who designed (or just marketed) the device was Courtney Hafflex but it has been awhile. These were sold in the early 70's when crystal motors on cameras were new and there was some anxiety that they might not run accurately to speed. The POM meter operated from a 9-volt battery. When switched on, the LED bars (or lights - there were alternate versions) would light up in accordance with a crystal in the device. Viewed through the spinning shutter of the camera, the LED's would be stationary if the camera was tracking speed and would be seen to "walk" forward or back if the speed were faulty. By photographing the running device at the head of a roll (usually only the first roll of the day) one could provide evidence that the camera was calibrated properly. David
  3. Jeff, thank you for your appreciation. If one lives long enough one gets to be a student of history. I recall also that our mutual friend, Mike Denecke, actively defended his patents. Of course, I think he was defending particular circuit designs and not attempting to protect something very general like the idea of a timecode slate. That would have been an uphill task as Ivan Kruglak and Coherent Communications had done that first. (As acknowledged on the Denecke website) I think patents serve us all best when they protect an ingenious solution to a particular engineering challenge and less well when they attempt to protect the first person to recognize the obvious and then attach a hands-off label to gravity or the idea of a film loop. I can't say whether this suspicion fits the present dispute. David
  4. I'm not sure if the information I have helps illuminate the matter or clouds the waters. This alternate version of a Nagra 4.2 is a new one for me but it's not that dissimilar to a Nagra modification that Neil Stone performed in the 1980's. To accomodate clients who already had a significant investment in mono Nagras when time code was first coming into use, Neil performed a conversion that enabled the mono recorders to lay down time code tracks. At the time, most mixers were delivering a mono track, even when using a stereo recorder, so the multiple tracks were not so important. As anyone who has listened to a playback of a timecode sync signal can attest, it is an annoying signal not easily separated from dialog. So, simply recording the code through a neopilot head wouldn't work; the timecode signal would corrupt the recorded audio. Neil replaced the mono and neopilot heads with stereo and center track heads from the Nagra TC. I believe there were also some circuit alterations to deal with the specifics of the timecode signal. That signal came from a Denecke GR-1 sync box that he simply fastened to the lid with velcro. Although the modified machine had two-track heads, it still had only mono circuits so the audio was still mono - identical in each track. These modified machines worked very well and served their owners well until standard practice moved into DAT machines and, subsequently, file-based recording. But the business of green knobs and an altered name plate doesn't look like Neil's work. I expect that another technician with engineering capabilities similar to Neil's took on the same challenge. David
  5. I cannot address the immediate issue of the validity of the Zaxcom patent or its applicability to the Lector PDR; even if I knew all the specifics, I am not an attorney. But I have a couple of brief stories that may be of interest. The movie business in California developed in large part because of a patent dispute. The Patents Company of Eastman, Edison and their partners held a patent on the intermittent movement that smoothly pulled down film, frame by frame, and permitted exposure of each image in regular succession. Part of the patent language specifically identified the use of a loop of film to permit a frame by frame advance without tearing the cellulose base. Independent moviemakers came to California in large part because it was far from New York and not heavily patrolled by Pinkerton detectives. Once here they found the climate to their liking. While making The Squaw Man, Cecil DeMille would safeguard the contraband camera and carried it each evening on the pommel of his saddle as he rode through Laurel Canyon to his rented house. On one occasion he said he was shot at. I've heard two stories regarding breaking the stranglehold of the patent: 1. When contested, a judge found the patent invalid because the use of a loop to feed the gate was an obvious solution, not an ingenious invention. 2. I've also heard that a consortium of independents researched the development of motion picture cameras and found a French design that predated the Edison/Eastman design, making their patent invalid. This seems more likely if less emotionally satisfying. At the beginning of my career, I worked at a camera store for a few years. We rented Ektagraphic slide projectors, the professional version of the popular Carousel. The Ektagraphics had a lock on the slide show market. The Kodak projectors were the only design to use a gravity feed; all other makers used some form of sliding gate to load and unload each slide. The gravity feed permitted the use of large capacity (carousel) magazines of slides and was very reliable. Eastman Kodak had patented that very element, the use of gravity to feed slides. Even Leica was forced to use a more cumbersome mechanism. I understand that the patent on that design was eventually challenged by the claim that gravity was an obvious element that could not be protected. Of course, it could just be that the growth of video made the issue of slide presentations no longer valuable. David
  6. In 2010, over several issues of the 695 Quarterly (now Production Sound and Video), I conducted some tests of antenna performance. I attempted to make comparisons that would reveal the advantages of various designs and identify exactly how much one type might outperform another. The results were generally instructive but trying to plot exact antenna performance is rather like trying to measure smoke. While patterns were discernible, a "weak" design would sometimes "hit above its weight" and confound expectations. I made the first tests and set the groundwork for subsequent investigations in the Spring 2010 issue: http://www.local695.com/Quarterly/695QuarterlyPDFs/695-Quarterly-2010-Spring.pdf (The early issues were archived only as full issues and not broken down by article.) As part of those tests, I mounted a cut-down whip on a transmitter to investigate how much range might be lost using the "wrong" antenna. The cut-down whip was about 1/2 the length specified for that radio. Always remembering the caveat that individual test runs are not necessarily indicative of future performance (sounds like the disclaimer of a stock broker), these were some results using proper length and cut-down antennas: Range using an SMQV at 50mW output with standard whips on the receiver: standard whip - 562 feet (receiver 8 feet above ground) cut-down whip - 358 feet standard whip - 518 feet (receiver 4 feet above ground) cut-down whip - 300 feet Range using an SMQV at 50mW output with SNA 600 antennas on the receiver: standard whip - 570 - 752 feet (distance to first isolated "hit" - end of range) cut-down whip - 390 feet standard whip - 670 - 743 feet (distance to first isolated "hit" - end of range) cut-down whip - 381 feet Half the proper length is a considerable deviation from ideal. As Larry Fisher of Lectrosonics has often said, in the best circumstances a bent and rusty coat hanger will function just fine as an antenna. But, under challenging circumstances careful attention to detail is likely to pay dividends. David
  7. I understand that a web host cannot refuse a request made on his birthday. Perhaps if site members were to ask him nicely, Jeff would extend a 30-day warranty for any item purchased from a JWSound member. But midnight approaches on winged feet and soon it will no longer be Jeff's birthday. David
  8. Thank you, Chris, for the clarification. I think I have the sense of the matter. (Or, at least as complete as I need.) David
  9. Happy birthday, Jeff (Is there an echo in here? I seem to have posted the same message of good will to two different threads. Well, I hope it's a doubly nice day.)
  10. Happy birthday, Jeff.
  11. A Nagra IV-L recorder with a Sennheiser 805 shotgun and Beyer DT48 headset. For documentary and industrial situations, that rig was sufficient 90% of the time and I learned about microphone placement by hand-holding the shotgun and listening to how the sound changed as I moved it about. (Of course, filming was single camera) David
  12. I've been following this discussion with some degree of confusion. I expect this is a matter of my lack of familiarity with the specifics of Tentacle gear and hope that one of you might clarify the matter for me. I'm generally familiar with the Denecke sync boxes. The operation light on those units will blink furiously when the device is first turned on and then settle down after about a minute of run time. However, if the device is jammed, the light immediately goes from rapid-fire to one blink every second. Seeing the stable flash confirms that the jam has taken and that the two clocks (source and slave) are either set to the same frame rate or to compatible cross-jam rates. The difference between rapid-fire blinking and once-per-second is conspicuous and no special 60-frames-per-second vision is needed to differentiate the two. Do the Tentacle units operate differently? Does one really try to match timing on two rapidly flashing lights to confirm operational lock? Thanks, in advance, for the clarification. David
  13. I think John Glenn had the wittiest take on the space program: I guess the question I'm asked the most often is: "When you were sitting in that capsule listening to the count-down, how did you feel?" Well, the answer to that one is easy. I felt exactly how you would feel if you were getting ready to launch and knew you were sitting on top of two million parts -- all built by the lowest bidder on a government contract." Of course, all those rocket components had to comply with an extensive set of military specifications - at least, I assume that's the case. Building equipment to price point yields some obvious advantages. The products are not usually innovative; rather they take advantage of innovations pioneered by others. But they are often able to offer a feature-rich device that capitalizes on tested designs and components mass produced for slightly different purposes. I think the Zoom recorders clearly fit this pattern. They use components made (probably) for portable radios, cell phones and the like and available inexpensively because they are produced in staggering quantity. This sort of re-purposing can yield a recorder that functions well and works reliably. The purpose-built device is always at a disadvantage when compared with mass produced competitors. Products from the top-tier builders use the best components available, chips that have stable operation over a wide temperature range or offer very long "cycles to failure" expectations. This is a hidden advantage that may not be apparent when comparing products on a showroom counter. And, the world being an uncertain place, there is no absolute guarantee that the advantage will work to your benefit in the field. Sometimes the premium IC will fail prematurely and the cheapo will run forever. But the odds are with the better stuff. Also, top-quality gear will often preform better at the ragged edges of performance specs. The best A-D converters may distort a bit less when overloaded than the low-cost alternatives. It's a distinction that is apparent only in extremes; 95% of the time the cheaper components seem to be a performance match. These distinctions are the reason professionals are leary of using products like Zoom recorders in critical applications although they may be entirely suitable when used as back-up gear. Now, for your peripatetic project, I would make a completely out of left field suggestion- I suggest you consider using a Nagra Mezzo. The little Mezzo, made in China but to Nagra specs, is really a product for reporters. http://www.nagraaudio.com/nagra-mezzo/ It will give you 24-bit recording in a device you can hold in your hand and slip into a breast pocket. The recordings are outstanding (assuming, as always, that you can get close enough to the sound source). It runs on 2 AA batteries. The built-in microphones are quite good - not Schoeps but certainly fine for anthropological applications. I've heard a recording of the organ at the Los Angeles Cathedral that is really outstanding. It costs $400, a lot if you compare it with the $100 Zoom competitor but a minor expense when you look at it as an all-in solution. It does offer manual recording as well as automatic level control and it has a built-in speaker so you can check your recordings. Or, if you were to decide to go with a larger package, say, a SD 744 + mixer, the little Mezzo could still be a useful addition for the circumstances where a lower profile was desirable and it could be the "bit-bucket" back-up recorder. David
  14. I don't know if this is directly applicable to Zaxcom compressors but I recall having a conversation with Bruce Bisenz about limiter settings for production audio. We were setting up the limiters in a Cooper mixer and he recommended (if I recall correctly) a medium-slow attack with release "as fast as possible." David
  15. I'm insufficiently familiar with the specifics of Sennheiser G3 packs to know if opening the case is possible but that's a good first start to any water intrusion issue. An actress once inadvertently dropped a Lectrosonics pack into a toilet and I was able to avoid serious damage by pulling the circuit board from the case so it could rapidly dry out. That's relatively easy with the Lectro - just two screws on that model pack. If removing the circuit board or completely opening the case is not possible, opening the battery compartment would probably be worth doing. David