Lyrec TR532 Series, Руководство пользователя

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11.5 SERVICE BULLETIN
Modification of: Code 1 servo system print
Purpose: Improvement of start up characteristic
Parts needed: 1 Transistor BC214
1 Resistor 10 kOhm
Modification:
1. The input pin 14 should be connected directly to resistor
R34. Move the existing wire from one leg of P8 to resistor
R34. Use existing hole close to R34.
2. Change value of resistor R34 to 10 kOhm.
3. Drill 2 holes and install a wire between collector of transistor
T18 and pin 37.
4. The grounded end of the three resistors R28 (47 Ohm), R30
(22 kOhm) and R32 (100 kOhm) should be disconnected from 0 V and
soldered together and with a wire be connected to the emitter of
the new transistor (BC214).
5. To install the new transistor drill a hole for the emitter. Base
and collector can be mounted in existing holes.
6. Collector of BC214 should be connected to pin 6. Drill a hole
close to the collector and install a wire. The other end of the
wire is mounted in existing hole.
7. Cut the printed circuit at 7.
8. The base of BC214 will now be connected to the moving arm of P8.
9. Cut the printed circuit at 9.
10. One and of P8 is connected to 0 V as before. No change
required.
11. The other end of P8 should be connected to pin 6. Use the
existing hole now made free (see paragraph 1) and connect the
other end of the wire to existing hole.
To install modified print, see Service Bulletin 11.4.
1978-05-01 TR532 11.5