Wurlitzer One More Time Vinyl, Руководство по эксплуатации

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Notes
OMT VINYL – edition: 13.08.2007
26
18.9.4 Note 3 B
The locating pulse ’101’ can be checked with the LED indicator K. For a check bring the record
preceding 101 beneath the gripper arm. Both K and Z then have to be dark. Do not mind if K is lit
when the carrier rests with 101/102 beneath the gripper arm. Then advance the carrier slowly (lift off
the drive as explained in note 3 A): K now has to light up by all means before Z but a very little
advance in time is sufficient and K must still be alight when Z lights up. Which LED then goes dark
first does not matter but K by all means must be out before Z lights up again for the next record
approaching the gripper arm.
If K lights up behind Z, the S&CC cannot find its starting position and the record to be located will
never be found, the carrier then rotates permanently. If K is still alight when Z lights up for 103/4, the
S&CC will consider this one as 101 and any record located will be that one ’behind’ the one actually
selected.
The light gate assembly can be shifted for about 1mm to find a proper timing.
Four K-signals in succession without a selection played in between causes a memory erase same as
if the LT button is actuated. Therefore, rotation checks with the carrier should be terminated with an
actuation of LT to prevent complaints raised by the first patron making a selection after the service,
that he lost his money because his selection led to the fourth K-signal in succession!
18.9.5 Note 3 C
The lamp of the light gates is one of 24volts, 3watts. The actual used voltage is reduced to about
12volts by a series resistor, or commencing with serial no. 6511 9514, by the 12volts regulator of the
amplifier. The Phonotransistors of the light gates can be checked with an ohmmeter at plug BLACK
when disconnected. Read between poles 3 and 5 for the gate K and between poles 2 and 3 for gate
Z. Results will be obtained only if poles 2 or 5 resp. are positive to 3, hence, interchange the poles
for a test. With an open light gate the ohms reading should be below kilo-ohms and with the light
broken it should be above 2 meg-ohms.
18.9.6 Note 4
Microswitch K8 is actuated by the large record clamp of the gripper arm. If this switch is maladjusted
or if the main cam and gear box stops before this record clamp is fully reacted, K8 will not be
actuated. This disables the changer for the next search run and keeps the turntable running all time
(please also see 4th symptom in
chapter 18.6, on page 22 .
The same situation, however, can be produced by a main cam and gear box running the proper rest
positions and stopping finally at a time when K8 is released again (please also see 2nd symptom in
chapter 18.8, on page 24 .
To test, actuate K8 manually and run the changer through some play cycles. The record clamp has
to actuate K8 before it reaches the most retracted position and has come to rest before it has passed
this position; compare the adjustment instructions.
If the system overruns the most retracted position with a K6 switch of proper adjustment, check R10,
the braking resistor parallel to (and located at) the motor, it should not read more than 55ohms.
18.9.7 Note 5
The A-side solenoid M6 is in circuit for an A-side selection for about 3 seconds only, counted from
the moment the carrier has stopped with the selected record beneath the gripper arm. Well within
these 3 seconds the shift rod is locked in its A-side position by the holdout cam already. The shift rod
is free to be moved manually at the time the changer is in idling position.
18.9.8 Note 6
With a dead motor MM check the carbon brushes. Used up brushes are not likely before some years
of service, however, a lack of contact pressure is feasible (binding brush holder). Watch for the
insulation ring at one end of brushs’ tension spring. Without this ring the motor is shorted and resistor
R15 will burn-out.