Teledyne UA-6, Installation And Operation Manual

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UA-6 Detector
Section 5 Maintenance and Adjustment
5-4
3. Loosen the two
1
/
16
inch set screws which secure the hub to
the metal shaft and lift the hub completely off the metal
shaft.
4. Loosen the pen holder screw (marked (A) in Figure 5-2),
remove it, and take off the first two of the three washers.
5. Remove the old pieces of the drive string.
6. Secure one end of the new drive string under the screw
marked (B).
7. Route the string through hole (C) and up through hole (D).
8. Place the hub back onto the metal shaft, ensure that is
properly aligned, and then tighten the two set screws.
9. Route the string 180 degrees counterclockwise (note
arrows in Figure 5-2) around the small pulley marked (F).
Then route the string through a washer and around the
second pulley.
10. Make one revolution clockwise around the hub and route it
up through hole (E) and secure it to the spring. Leave
enough tension so that the spring extends about 1 millime-
ter.
Note
You may find it difficult to secure the string to the spring while
maintaining a slight tension. If so, secure the string to the
spring, then loosen the machine screw (B) and draw the ten-
sion from that end of the string. Then retighten screw (B).
11. Install the T-shaped stop bracket removed in step 1 and
rotate the hub counter clockwise until the trapezoidal stop
is against the stop bracket.
12. Complete the string installation by threading the pen
holder screw (A) back through the washers. Be sure the
washer with the string through it is in the middle. Then
tighten the screw to retain the string to the pen holder
when the pen is slightly above full scale (100%).
5.3 Timing Belt Tension
Adjustment
1. Remove the case following the procedure in Section 5.1.
2. Loosen two screws securing the motor mounting bracket to
the side plate of the recorder. Removal of main circuit
boards may be necessary unless a right angle (offset)
screwdriver is used to loosen motor screws.
3. Slide the motor bracket back to increase tension on the
timing belt and tighten the two screws.
CAUTION
Do not apply too much tension to the timing belt. The timing
belt should just be tight enough to ensure that the teeth do not
jump out of the sprocket depressions.
4. Install the case following the procedure in Section 5.1.