Ampex 351 - Page 85

ion
PIN 2
■>PIN I
Microphone response set-up
Step 4:
Step 7:
Step 8:
8-12
Step 5:
Step 6:
Step 2:
Step 3:
Record Alignment of Stereophonic Equipment
Treat each amplifier as though aligning
for single track operation, and following the
instructions in this section, proceed in this
sequence:
1. Center the noise balance (slot parallel to
plane of the chassis face panel if it is not
within 45° of center position).
Head Azimuth Adjustment
Because taere are two heads in each record
and reproduce stack, make the azimuth adjust 
ment for fin average maximum meter indica 
tion, adjusting first one head and then the
other, and finally adjusting for the average
maximum meter indication.
This compromise azimuth adjustment ap 
plies to reproduce and record heads alike.
When aligning the record heads, energize the
record relays by depressing the record buttons
on each electronic assembly.
NOTES ON ALIGNING
STEREOPHONIC EQUIPMENT
Stereophonic equipment, consisting of two
electronic assemblies — a master and a slave,
and two track head assemblies, is aligned in an
almost identical fashion to the monaural sys 
tem by considering and aligning each amplifier
separately.
Certain simple differences are outlined for
the user ’ s guidance. Before attempting align 
ment of the two track stereophonic equipment,
note the instructions for each category.
Microphone Response
Connect an audio oscillator as shown in the
illustration and make the response check by
sweeping the oscillator through the frequency
range to be checked.
Frequency Response
Frequency response checks can be made on
both systems simultaneously, or the tracks can
be checked individually.
3. Set the BIAS ADJUST trimmer for proper
indication.
4. Set the record calibration for proper read 
ing. Repeat on second channel.
2. Set the ERASE ADJUST trimmer for
proper indication.
89-0144
Issue A
NOTE
When the METER and OUTPUT
SWITCH is in the ERASE position,
meter readings must be made with
only one amplifier in the record mode
because, if both amplifiers are record 
ing, false readings will be taken.
22Ofl
AW
I0K
A/W
Position the number one amplifier
RECORD LEVEL knob fully counter 
clockwise.
Disconnect any input.
Place amplifier number one ONLY in
the record mode.
Plug a set of earphones into the moni 
tor jack and listen for the minimum
noise location while adjusting the
noise balance control.
Stop the recorder.
Perform steps 1 and 2 on amplifier
number two.
Place amplifier number two ONLY
in the record mode.
Listen for the point of minimum
noise while adjusting the noise bal 
ance control. Noise balance control
slots should be within 45 degrees of
a line paralleling the face panel of
the chassis.
ji
-> PIN 3
Noise Balance Adjustment
Step 1:
MAINTENANCE AND
TROUBLESHOOTING
General Maintenance Information
Faithful adherence to the recommended
ROUTINE MAINTENANCE found in SEC-