The Guardsman uses a clock movement very similar to the other Detex units. However, the tape guide path and drive mechanism are quite different. Figure 3 shows a unit with the back open to reveal the tape drive details. The major elements of the tape path are numbered and identified below.

1. Supply roll of tape

2. Recording mechanism (shown with cover removed in Figure 7)

3. Tape clamp to hold the tape against the sprocket teeth

4. Tape cutter to allow for removal of used segment of tape

5. Annular tape holding channel

6. Tape drive sprocket

As the tape is taken from the supply roll, it is pulled past the recording mechanism where the station key stamps its number at the appropriate time line. The sprocket then pushes it past the tape cutter, along the guide path, and into the annular holding channel.

The friction in the channel is such that approximately four turns of tape can be pushed into it before it starts to bind. Since each turn represents about 34 hours of tape, this equates to a total capacity of about 136 hours. Therefore, the required four-day (96-hour) segment of tape can be accommodated with a substantial margin before binding will occur.

Although in normal operation the used tape would be removed and checked daily, this extra capacity provides for continued use over weekends or holidays up to four days duration.

 Removal of the three large screws around the edge of the clock plate allow the movement and drive sprocket to be taken out as a unit. This is shown in Figure 4. The movement as viewed from the dial side is shown in Figure 5.

As mentioned previously, the clock movement is very similar to those used in most Detex watchclocks. It is a very well made eight-day unit that actually runs about 10 to 12 days if in good condition. It has nickel plated brass plates and utilizes an 11-jewel platform escapement. These were made by several suppliers over the years; clocks made by organizations like Chelsea used escapements by the American Waltham Watch Co. Detex started producing their own movement in 1951, using an escapement by Recta S.A., of Switzerland. The Recta escapement had also been used from time to time in earlier movements. The majority of Detex clocks encountered today utilize this Swiss Recta platform escapement. The side view of the movement in Figure 6 shows this platform escapement.

After removal of the hands, dial, and dust cover, the gold-plated escapement is easily accessible. A note about the hands: As in other Detex units, the endshake for the minute wheel is maintained by placing a stop at the top of the minute wheel pipe rather than with a spring dial washer as is done with pocket watches. In earlier units this was a large-head screw in the end of the center arbor. In this case, that stop is a thin, blue steel washer held in place with the cross pin visible in Figure 5. This pin does not hold the minute hand on, as it might if this were a wall clock, but only retains the washer that sets the endshake. The hand is a press fit on the pipe.

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