Jvc SEA 70 Service Manual

Page 2

Contents

1. Specifications ........................
2. Removal Procedure of Top Cover ...........
3. Main Parts Location
3-(1) Top View .......................
3-(2) Front View ......................
3-(3I Rear View .......................
Exploded View .......................
Block Diagram ........................
Service Precaution .....................
Adjustment Procedures
7-H) Center Voltage Adjustment ...........
7-(2I Gain Adjustment ..................
8. Printed Circuit Board Assy and Parts List
8-(1I TXX-259 Functions Switch & Pin-jack
P.C. Board Ass'y ............
8-(2) TXX-260 S.E.A. Resonator P.C. Board
Ass'y ...................

$95?

1 . Specifications

Circuitry
Buffer amplifier

: FET-equipped, lCL-input, dou-

7

9

bIe differential, equiphase-feed-

back circuit.
: Double-differential input, DC
configuration circuit.
Semiconductor-L cuicuit : Transistor-Inductor cuircuit.

S.E.A. amplifier

8-(3I TXX-277 AC Socket & Fuse P.C. Board

Ass'y ................... 10
8-(4) TAO-515 Power Supply & S.E.A. Amp.

P.C. Board Ass'y ............ 11
9. Accessories List ....................... 13
10. Packing Materials ...................... 13

11. Parts List with Specified Numbers for Designated
Areas .............................. 13
12. SEA-70 Schematic Diagram ............... 14
13. Connection Diagram .................... 16

Warning:

When placing the parts marked with A , be sure to use
the designated parts to ensure safety.

Total harmonic distor-
tion

Intermodulation distor-
tion

Gain

S/N ratio

: 0.003 % (20 Hz - 20 kHz, rated

output)

: 0.003 % (with all S.E.A. controls

positioned at "0")

: 10 - 100,000 Hz (+0, -2 dB)
: 118 dB (at rated output, IHF A-

Input Section network short-circuited)
SEA INPUT : Input impednace 47 k-ohms 0001 section
TAPE MONI : Input impedance 47 k-ohms SEA center frequencies : 16 Hz, 31.5 Hz, 63 Hz, 125 Hz,
Output section 250 Hz, 500 Hz, 1 kHz, 2 kHz,
SEA OUTPUT : Output impedance 100-ohms 4 kHz, 8 kHz, 16 kHz, 32 kHz
TAPE REC : Output impedance 100-0th SEA control range 1 112 dB/i6 dB
(during SEA-recording) General
Rated output : 2 V RMS (with all S.E.A. con- Power source : See attached table
trols positoned at "0") Dimensions : 420(W) x 159(H) x 318(0) mm
Max. output : 8 v RMS (with all S.E.A. con- Weight : 6 kg
trols positioned at "0")
Power Specifications
EUROPE, U.K. & MILITARY MARKET &
CANADA 8 USA AUSTRALIA OTHER AREA
Power Supply AC 120 V», 50/60 Hz AC'110/120/220/240 V» AC 110/120/220/240 V'v
selectable, 50 Hz selectable, 50/60 Hz
Power Consumption 25 W 25 W 25 W
Power Outlet Fitted Not fitted Fitted
Fuse (PrimaryHF001) OMF61U1-R50 OMF51A2-R315L 0MF51A2-R315L
(0.5 A} (T315 mA) (T315 mA)

SEA-70
No. 2527