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Eclair ACL Muffling the Many Milliframe Misconceptions Muttered

Some rather uninformed speculation has been posted here lately, which I would like to clear up.

The first Tobin Milliframe Controller model, TMC-55, was initially made to interface only with Arri cameras having the 3200 PPF (pulse per frame) signal input. This is a TTL/CMOS 5 volt p-p signal, negative ground. The Controller is powered by the camera, receiving a constant 12 volt DC as long as the battery is connected. This voltage must be applied before the camera is started up. When the two-color decimal point changes from flashing red to a steady green, it is safe to start the camera. This model came with a permanently attached 11-pin Fischer cable.

Later, when we discovered that the Arri 16-SR High Speed required instead a 1600 PPF input, this signal was added.

At the same time, we added the 100 PPF signal to suit the Aaton cameras, which used a different connector, the 9-pin WPI Tiny Tim (formerly Amphenol.) These two changes required a detachable cable to suit the various models, resulting in the model TMC-55Aa. Some of our own crystal control motors were designed to use less expensive connectors than the Fischer. The actual signals, however, were the same 100 or 3200 PPF frequencies as used with the standard Arri and Aaton. (As an aside, frequencies of 25, 50, 200 and 400 PPF were also available from the TMC-55Aa, but no equipment was ever made to use any of them, so they were deleted from subsequent models.)

Since some users needed only the 23.976 and 29.970 FPS NTSC speeds, we then introduced the Tobin Videoframe Controller TVC, which used the same cables as the TMC-55Aa.

The next generation Milliframe, the TMC, uses essentially the same circuit as the TMC-55Aa but in a more compact box. To enable the addition of a Run-Stop switch, and a footage counter in the TMC2, the output connector was changed from 9-pin female to a 9-pin male. This prevents camera or controller damage from using the wrong cable. The footage counter divides the 5 volt frame pulses from the camera by 16 or 40 to display 35mm or 16mm feet respectively. The available output signals remain 100, 1600 and 3200 PPF as in the original model.

The Videoframe Controller was revised to also include the Run-Stop switch, as the TVCe, and it was also changed to use the same cables as the TMC2.

The TMC2 and TVCe units can be seen on the Tobin website in the Catalog section, at http://www.tobincinemasystems.com . The instruction manuals, including pin connections, are posted oddly enough in the Instruction Manuals section.

To compute the frequency, multiply the FPS by the PPF. That is, for 24 FPS the reference frequency is 76,800 Hz for the Fischer and 2400 Hz for the WPI.

Clive Tobin
info at tobin cinema systems dot com
www dot tobin cinema systems dot com
Clive Tobin

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