Description of the electrical
functions when changing records
Record Lift
When the selection of the desired record
(raised selector pin) is complete, the magazine
motor, controlled via the MI2 contact, moves
the record magazine with the MSK contact
against the selector pin raised up.
At the moment of contact between the
insulated brass bracket (MSK contact) on the
record magazine and the selector pin, the
resulting earth connection (plus) switches on
the W relay, which holds itself via the wIII2
contact. At the same time, the wIII1 contact
causes the M relay to drop out.
By switching the wI1 contact to the wI2 contact,
the magazine motor is switched off and the
player motor is switched on. The brake
connected in line with the player motor also
applies. By releasing the brake, the lift spring
acts, which takes over the gear transmission to
transport the record into the play position.
The following electrical switching functions are
carried out by the cam contacts NK1 to NK5 on
the changeover gear during lifting.
1) By switching the NK1:
a) the magazine motor is interrupted again
and
b) prepared the return of the player engine
2) The NK2 closes and prepares the switching
on of the M relay for the later return.
3) By switching NK4, the centering magnet
picks up.
4) The NK5 closes and prepares to switch on
the reset magnet.
5) By switching back the NK4:
a) the centering magnet is switched off so
that the record can be pressed against the
turntable by the centering plate using spring
pressure.
b) The reset magnet is switched on.
6) The NK5 opens and brings the reset magnet
to waste.
7) The NK3 controls the muting of the amplifier
when the plate is changed, so that the
placement of the tonearm and the brushing of
the sapphire are not transferred. As a last
function, when a plate is placed on the NK3, a
relay in the amplifier is interrupted, which drops
out after a delay and switches on the anode
voltage.
Return the played record
The tonearm switch-off contact is located on
the back of the pickup. When the record is
played, i.e. when leaving the lead out groove,
the switch-off spring touches the TA contact
and causes the W relay to drop out due to the
resulting mass connection by short-circuiting it
via a resistor. The M relay receives voltage via
the wIII1 contact and picks up. At the same
time, the player motor is repositioned via the
wI1 contact, which in turn actuates the cams
NK1 to NK5 and the cams NM via the gearbox.
In that the returning lifter returns the records to
the record magazine, the switching sequence
of the cam contacts is in the reverse order to
when the records were placed. when the
player motor runs out, the NK1 switches over
and starts up via the mI2 contact cdn
magazine motor, and also moves the selector
motor via the mI1 contact. When the record
magazine rotates, the NK7 cam contact is
opened briefly, causing the M relay to drop out
(selector motor switched off).
After a further full turn, the shut-off cam of the
record magazine actuates the NK6, opens it
briefly, and also stops the magazine motor via
the deactivated relay.
If several records have been selected, the
same procedure as described will be repeated
after the return of the first record has ended.
The magazine motor moves the MSK contact
against the high-positioned selector pin, the W
relay picks up again, etc.
