Ampex 351 Series - PERFORMANCE CHECKS

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SUMMARY
For Gain
Component New Value
New Input Imp edance
Increase
BAL BRIDGE UN BAL BRIDGE
10 db BAL BRIDGE
Rl 33K o hms 66K ohms
30K ohms
and UNBAL BRIDGE R5
12K ohms
14 db UNBAL BRIDGE
R5
zero (
short out ) 200K ohms
50K ohms
R4
100K
ohms
10 db BAL BRIDGE
Rl 33K ohms 66K ohms
33K ohms
R5 27K ohms
R4
5.6K ohms
PHONES
High impedance head phones must be used.
To
monitor the incoming line or reproduce
output. plug the hi gh impedance phones into
phone jack J6 PHONES on the amplifier face
panel or ]4 MONITOR on the back of the
amplifier chassis. The monitor jack J4 is a
high impedance unbalanced output isolat ed
from the main line . To preserve low frequency
response, feed into an input impedance SOK
or higher. To preserve 11igh frequency response
the cable shou ld have not over 500 uuf of
capacita nc e.
RE MOTE CONTROL
The operation of the t ape transport m ec han-
ism can be remotely contro ll ed by a Remote
Control Unit. The catalog No. 5763-00 or
5763-02 unit is supp lied in a wooden case,
completely
wired and r eady to plug into the
remote control
connecto r, J502S, on the tape
transport circuits assembly. The catalog No.
5763-01
and 5763-03 units are mounted on a
flat
plate for installation in studio consoles,
and are not wir ed. For Model 351-2, use 5763-
02
in the wooden case or 5763-03 mounted on
the flat plat e. To install , wire as shown in the
figure (Sc hemati c Diagram, Remot e Control
Unit ) located in SECTION 5, and plug into
J502S.
NOTE
Whenev er th e r emote control unit is
not connected, the dummy phtg
P502P, supplied · with the equipment,
must be plugged into ]502S .
60 CYCLE AMPLIF I ER
The Ampex Model 375 Precision 60 Cycle
2-5
Amplifier
can be plugged directly into tJ1 e
equipment at J503S. No other connect ions arc
necessary. The Model 375 is used where power
sources are errat ic and there is n ee d for a pre-
cision
60 cycle time base for diivin g th e cap-
stan.
CAUTION
If this unit is used with the Recorder/
Reproducer, the control circuit fuse
F402 must be increased to 5 amperes.
NOTE
Do not remove the dummy plug
P503P unl ess th e 60 cycles amplifier
is con necte d.
OVERALL PERFORMANCE CHECK
(Read SECTION 3, OPERATION before mak-
ing these ch ecks.)
Make the following e quipment performanc e
checks
at the tjme of installation an d when
necessary thereafter:
REPRODUCE ( Playback) LEVEL
REPRODUCE (
Playback ) RESPONSE
REPRODUCE (Playback)
NOISE
MEASUREMENT
RECORD CALIBRATION
FREQUENCY RESPONSE
RECORD
NO I SE MEASUREMENT
NOTE
It should be noted that this machine
has been adjusted at the fact01y to