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Using the TCS "TVC e"
Tobin Videoframe Controller
Applications
The TVC e is used for double-system sound filming, for later transfer to USA format video tape on a Rank or Bosch (etc.) film scanner, in conjunction with audio on DAT (digital audio tape,) CD (compact disk,) MiniDisc, or Hi-Fi video tape such as 8mm, Hi-8, VHS, etc. that cannot be resolved or speed controlled. Since the speeds of the TVC e are the same as the USA NTSC video transfer speeds, that is 23.976 or 29.970 FPS (frames per second,) you are working in real time both filming and in the transfer. The audio is self-resolving and will play at the same speed as it was recorded, so synchronization will be maintained without the need to correct the speed of the audio reproducer with expensive time code chasing equipment. It is of course still necessary to use a clapstick to establish the start point of each shot. Since general purpose audio equipment is usually not adjusted as precisely as film sound crystal sync equipment, the best sync may result when playing back on the same machine you used in the field.
The 23.976 and 29.970 speeds are not HMI compatible, so if you are filming with regular HMI or fluorescent lights a slow pulsation of exposure may be noticed in the film. This can be reduced by setting your variable shutter to 144° for 23.976 or 180° for 29.970 FPS, and/or by using "flickerless" (square wave) ballast HMI lights. It can be totally eliminated by using daylight or high-wattage tungsten lights.
The TVC e is also useful for filming from NTSC (USA system) TV sets or video monitors. Use the 29.970 speed. Your camera must have a mirror shutter to see the effect, ideally with a 180º shutter opening for the narrowest shutter bar. When you start filming, push the "Phase" button to move the shutter bar to the bottom or other desired place on the monitor screen. (If using an Arri 16-BL, the mirror shutter has an extra stripe on it that can be confusing. The true shutter bar is the narrow one; disregard the wider bar, which is the mirror stripe.)
For filming from computer screens, every one is a different odd speed according to the whim of the video card designer, so you should instead use the Milliframe Controller.
Attachment
Connect the DE-9F end of the cable to the TVC e. Plug the other end into the camera. Cables are available with several connectors to suit the various models of cameras and crystal controls. The TVC e uses the same cables* as the TMC and TMC2 Milliframe Controllers.
The cables for the previous models TVC and TMC-55Aa will not fit and are wired differently, and thus cannot be used with the TVC e.
*The TVC e cannot be used with the TXM-22 and TXM-27.
Changing Settings for Certain Cameras
If your camera is an Arri 16-SR High Speed, it is necessary to change a jumper inside the TVC e to get the correct speeds, otherwise the camera will run twice as fast.
NOTE: the circuitry inside is static sensitive. Ground your body to a water pipe and keep touching the metal shell of the DE-9F connector to equalize charge.
Remove the four cover screws and lift off the bottom cover. You will note a jumper on the bottom of the circuit board is linking two of three gold pins, with the center pin linked to the adjacent pin on one side or the other. For use with the 16-SR High Speed, pull the jumper straight out and re-attach it in the "16SR-High Speed" position. Replace the lid and lid screws.
To restore normal operation, replace the jumper in the "Normal" position instead. If your other camera uses the Aaton, WPI or RJ-12 cable, or is equipped with the TXM-20 or TXM-20B crystal motor, it is not affected by this jumper and it can be left in either position.
Operation
There are three user controls on the front of the unit.
The Frames per Second Speed switch selects the running speed. Move it to the right for 23.976 (FPS) and to the left for 29.970 FPS. If filming from a video monitor, with the camera running at 29.970 FPS push the Phase button with your fingertip until the shutter bar is where you want it, and then release the button.
The Run-Stop switch controls the running of compatible cameras. Push to start, push again to stop.
The Sync Alarm light on the camera will show whether the desired speed is being maintained. The green Pilot Light on the TVC e shows that the unit is connected and is getting power.
Note that some cameras must have the camera's speed dial set to a specific speed, often 24 FPS, in order for an external speed reference such as from the TVC e to be correctly applied. Refer to your camera or crystal motor instructions. Correct running can be verified by selecting 29.970 FPS on the TVC e and watching for a stationary shutter bar on an NTSC (USA system) TV set that is tuned to a broadcast station.
Additional Information (for technicians)
Apart from the Normal / 16SR-HS jumper there are no user adjustments inside. Do not disturb the trimmer capacitor used for making a fine adjustment of the crystal frequency, unless you are properly equipped to do so.
To make up your own cables, the following pins on the DE-9 connector (male in the TVC e, female on the cable end) are used for the following purposes: Pin 6 is +12 to +24 volts Power, 5 & 9 and the connector shell are negative Ground. Other pins are 5 V CMOS logic, pulses per frame (PPF) as shown: 1=no connection, 2=3200/1600PPF output according to the jumper, 3=100PPF output, 4=run switch, 7=run switch, 8=3200/1600PPF output according to the jumper. These connections are the same as on the TMC and TMC2 Milliframe Controllers, except that on the latter units the pin 8 output is not affected by the jumper setting, and pin 1 is the added 5 V frame pulse input for the TMC2 footage counter function.
The only service adjustment is the crystal trim setting. Connect a frequency counter to 74HC4060 pin 9 and ground. Adjust the trimmer for 6137.862 kHz or 7672.327 kHz ±20 Hz according to the crystal marking. The lower frequency crystal must have jumper J6 installed, and the higher one has jumper J7 installed instead.
Tobin Cinema Systems, Inc.
http://www.TobinCinemaSystems.com
TVC e Grey Instr.pub rev 040826
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