(5) Repeat the procedures in (2), (3), and
(8) Turn the selector switch to the TRANS-
MIT position and, with the spot of light
(4) above until the final adjustments of
GAIN and CONTRAST controls give
on the blackest portion of the copy, trans-
meter readings differing by at least 15
mit a maximum signal for approximately
db between the blackest and whitest
15 seconds. This should be enough time
portions of the copy. The maximum
for the receiving operator to adjust the
reading (on black copy) should not
controls on his set; then alternately send
exceed +2 db.
maximum and minimum signals (with the
spot of light alternately on the blackest
(6) If the UC coupling coil is used to couple
and whitest portions of the copy) for
the transceiver output to a telephone
about 5 seconds each, so that the receiv-
circuit, an additional adjustment must be
ing operator can check the contrast set
made at this point. With a +2 db meter
up by the transmitting operator. After
reading, indicating maximum trans-
some experience, this procedure can be
mitted signal, turn the selector switch to
shortened on subsequent transmissions
the TRANSMIT position. Listen closely
over the same circuit by sending only
in the telephone earpiece, and slowly
minimum signals for receiver adjustment.
rotate the coupling coil on the telephone
c. Transmitting Phasing Pulses.
headset until the loudest tone is heard.
(1) Move the drum so that the spot of light
Be sure that the coupling coil is at least
shines directly on the raised phasing ring
2 feet from the transceiver, power supply,
at the left end of the drum (fig. 17). The
and other electrical equipment to prevent
STANDBY-MON-TALK switch may be
magnetic pick-up of interference.
in the MON or STANDBY position, and
(7) When using any model of the transceiver
the selector switch is at SET RANGE.
except TT-1/TXC-1, set the selector
Operate the START switch and hold it
switch at STANDBY.
Operate the
engaged until the motor starts and the
STANDBY-MON-TALK switch momen-
drum picks up speed to slightly more
tarily to TALK and inform the receiving
than 60 rpm, which is the normal oper-
operator that maximum and minimum
ating speed. (Do not race the motor;
signals will be sent. This will permit the
2 to 4 revolutions of the drum should be
receiving operator to make proper ad-
sufficient.) Release the START switch.
justments on the transceiver being used
The drum will slow down to a synchro-
for reception. Release the STANDBY-
nous speed of 60 rpm as indicated by the
MON-TALK switch and it will snap back
1,800-cycle audible tone from the motor
to MON position. This enables the
laminations.
transmitting operator to hear the re-
Warning: The motors of Facsimile
receiving operator's acknowledgment.
Transceivers T T - 1 B / T X C - 1 through
When using Facsimile Transceiver TT-
TT-1F/TXC-1 may run at nonsynchro-
1/TXC-1, external telephones must be
nous speed. It is at synchronous speed
used for voice communications between
only when the 1,800-cycle tone can be
operators. However, if no external voice
heard from the motor laminations.
communication circuit is available, with
(2) If the drum stops, repeat the starting
Facsimile Transceiver TT-1/TXC-1 mod-
operation. When the light shines on the
ified by MWO SIG 11-2258-1 being used
white phasing spot of the phasing ring,
at the receiving end, the maximum and
phasing pulses are transmitted. This is
minimum signals can be heard by the
indicated by a flicking of the DB METER
receiving operator when the selector.
each time the light shines on the phasing
switch on the receiving transceiver is set
spot. Look through the clutch window
to STANDBY. When operating blind,
and make sure the drum is driven by the
this would be a signal for the receiving
stop arm driving the dog trip arm (fig.
operator to turn the selector switch to
one of the record positions for setting the
automatically after 5 to 10 revolutions of
contrast of his machine.
the drum. If the stop arm is not driving
