Sony TC-777-2 User manual

Table of Contents
SPECIFICATIONS
BLOCK DIAGRAM
3
TECHNICAL FEATURE 4
CABINET — TOP VIEW
CABINET — SIDE VIEW Model 777-2/-4
6
CABINET-SIDE VIEW Model 777-2J/-4J 7
CHASSIS-TOP VIEW 8
CHASSIS-BOTTOM VIEW
9
METHOD OF DISASSEMBLING THE SET
10-11
MECHANICAL ADJUSTMENT 12-13
ELECTRICAL ADJUSTMENT
13-17
17
MODIFICATION TO DIFFERENT POWER LINE FREQUENCY
.... 18
LEVEL DIAGRAM
19-24
CIRCUIT SCHEMATIC MODEL TC-777- /- J
2 -32
MOUNTING DIAGRAM
33-38
CIRCUIT SCHEMATIC Model 777-2J/-4J
WIRING OF HEADS
39
40-48
EXPLODED VIEW
Page
2
SONY
SERVICING GUIDE

Specifications
4 track monophonic
Head Composition:
Inputs :
2
Outputs :
2
0 dbs (0.77 V)
1
1
outputs :
Motors :
Dimensions :
Weight:
2 -
1
1
1
Signal-to-Nolse Ratio:
Flutter and Wow:
Blas Frequency:
Recording Time:
(with 1,800 ft tape)
Power Requirements:
Tape Speeds:
Reel Size:
Frequency Response:
2 track monophonic
& 4 track stereo
1 hr 30 min
3 hrs
3 hrs at 7'/i ips (19 cm/s)
6 hrs at 3J4ips (9. cm/s)
1
1
1
1
1
1
2
IC- 24R, ;
UC-124R;
17*/, (W) x 177. (0) x 8'7..' (H)
(44 mm x 4 8 mm x 216 mm)
42 lb 14 oz (19. Kg)
AC 100, 110, 117, 12 , 220 or 240 Volts 0/60 Hz, 90 Watts
7% ips and 3?4 ips
Up to 7* (18 cm)
±2 db 40-16,000 Hz at 7% ips (19 cm/s)
0-9,000 Hz at 3?; ips (9. cm/s)
Better than 0 db (at peak recording level)
Less than 0.1% at 7>4ips (19 cm/s)
Approx. 92 KHz
2 track stereo
tc -777:V:4 j j
Line ...........................................................
Model 777-4
high impedance (100 KQ)
-12 dbs (0.22 V)
Model 777-2 and 777-2J -4J
high impedance (100 KQ)
-10 dbs (0.2 V)
Line Outputs .....................................
low impedance (600 Q)
high impedance (10 KQ)
Stereo monitor ...............................
high impedance (10 KQ)
Model 777-2J -4J
Record/Playback Connector
inputs: load impedance 100 KQ
-33 dbs (0.02 V)
load impedance 100 KQ
-3 dbs (0.68 V)
HC-634D, ; Capstan ..........................................
Reel ....................................................
Reel ....................................................
4 min
k 1 hr 30 min
Model 777-4 -4J
ERP24 2902; 4 track erase/4 track record
PP30-4202LNS ; 4 track playback ...................
PP30-2802LN ; 2 track playback ...................
Model 777-2 -2J
ERP24-2202 ; 2 track erase/2 track record
PP30-2802LN ; 2 track playback ...................
PP30 4202LNS ; 4 track playback ...................
Microphone ..........................................................................
Model 777-4
low impedance (2 0 — 600Q)
-72 dbs (0.2 mV)
Model 777-4J
low impedance (2 0 — 600Q)
-60 dbs (0.7 mV)
Model 777-2
low impedance (2 0 — 600Q)
-68 dbs (0.3 mV)
Model 777-2J
low impedance (2 0 — 600Q)
-60 dbs (0.7 mV)

CH 1
CH 1
Mic Pre -Amp
Record Equalizer
Record Amp
Mic
Bias Oscillator
X-..;: -.o;
Playback
6
Playback
CH-1
Line Out Amp
■©
Track Selector
Equalizer
Line Out
Selector
Channel -2
VU
(Same as Channel - 1 )
Power Rectifier
Voltage Selector
AC
D
t
Tape Transport
Control Circuit
If
TC-777
CH-l
Record Equalizer
REC H
Record Amo
Bias
CH-l
E H
Oscillator
Bias ON/OFFSW
Line-Out Amp Track Selector
VU
Channel -2
AC
i
(Same as Channel 1)
Power Rectifier
3
Block Diagram
StiS OsCil'atCr
Record Amp
Line Out Amp
Playback Amp
Mic Pre-Amp
Playback
Equalizer
Selector
Tape Transport
Control Circuit
CH 1
REC H
Bias Oscillator
Record Amp
Line -Out Amp
Pla/bac* Amp
Mic Pre-Amp
CH-1
4 track
P B H
CH-l
2 track
P.B H
CH-l
2 track
P B.H
CH i
4 track
P B.H,
CH 1
E H
Playback
X
S ’
g
o ----------------- •
Bias ON/OFF SW
Tape
Source
Moni SW L
TC-777z<j
Xioi tc«
Pre Amp
Xios tot
tape
Source
Mon. SW
X ioi io ?
CH-l
©-
Line input
ch
Mic input (O q
tc -777:1/ i ;
input
CH-l
’ ^9) Loe-Out
Line input
117V
IIOV
— — 0

Tape Transport Mechanism
Head Arrangement
The Head Assembly consists of three Heads with the following stack arrangement:
f
TC777-2/-2J
2 Track Playback
4 Track Playback
PP30-2802LN
PP30-4202LNS
TC777-4/-4J
— 4 —
Technical Feature
□rm
den
SONY Model 777 Series Stereo Tapecorders are high quality precision instruments for professional
three Heads, three Motors, all transistor Amplifiers and perfect push button operating system.
2 Track Erase
/2 Track Record
ERP24-2202
4 Track Erase
/4 Track Record
ERP24-2902
2 Track Playback
PP30-2802LN
4 Track Playback
PP30-4202LNS
TC-777in
The head located at left is Electro-Bi-Lateral Head which Two (Four) Track Erase Head and Two (Four) Track Record Head
are enclosed in one shield case. Two Track Playback Head and Four Track Playback Head are perfectly shielded with the
permalloy-copper-permalloy shield cases.
use provided with
The tape transport mechanism is operated electrically with three Motors, two Solenoid Plungers and three Relays switch 
ing the Motors and the Plungers.
For driving the capstan, Hysteresis Synchronous Motor, whose rotation synchronizes perfectly to power frequency and is
not influenced by power voltage change, is used Speed change is available by changing numbers of the pole, viz. 4 poles
for 19cm/sec (7-1/2 ips) and 8 poles for 9. cm/sec (3-3/4 ips). For Feed Reel Motor, Eddy Current Motor with outer
rotor is used and gives proper back tension to the tape with low voltage operation in Forward Mode and rewinds the tape
with high voltage operation. For Take up Reel Motor, 4 Pole Induction Motor is used and operated with low voltage
in Forward Mode and with high voltage in Fast Forward Mode.
Brakes of Take-up and Feed sides are released when a Solenoid Plunger is pulled, and Pinch Roller is pressed by ano 
ther Solenoid Plunger.

— 5 —
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