Fisher CA 78 Service Manual

Page 1

SERVICE MANUAL

FISHER®

Integrated
Stereo Amplifier

w.» e um!

U.S,

Page 2

CONTENTS SPECIFICATIONS

Functional Block Diagram .......................... .l 2 AMPLIFIER (BA-78
Specifications ............... 3 POWER AMPLIFIER SECTION
, . 4 Mlnlmum HMS sine wave power per channel
D'sassemny InStrUCIlons """ wlthin stated bandwidth atno more than stated 65 Watts
Recommended Test Equipments ......................................................... 5 distortion and with B-ohmlaad
Harmonic Distortion Test ................................................................. 5 power Bandwldh . 20 Hz_ 20 kHz
Cabinet 8t Chassis Exploded View ....................................................... 6 Total HarmonIc Distortion 0.2 %
Parts List ................................................................................... 7 I'MIDismmon 02% "
Connecting Diagram .............................. .. 8 SpeakerDamping >20
' ' ' BIockDia ram ..... . 9,10 _
'C_Eq"a.'em,0"° 8 _9 PREAMPLIFIER SECTION
Printed Cll'CUIt Board (Bottom View) .. ........ 11,12,13,14,15 Frequency Response
P.C.B.Assy Parts List ...................................................... 16,17.18.19,2O Phono (RIAA) 10.5 dB
Pointto PointWiring Diagram ...................................... . ................. 21,22 . AuxI20 Hz_20 kHz) ' $015118
Schematic Diagram .................................................................. 23,24 InputSensitivity andlmpedance
Semiconductor Lead identification ..................................................... 25 Phono 245 mV/50kl1
Tape Monitor 150 mV/50 kn
Tuner/Auxiliary 150 mV/50 kl)
Phono Max.lnpulCapability 170 mV
Graphic Equalizer E,,___.___.
50 Hz :10dB
FUNCTIONAL BLOCK DIAGRAM mm mm
1 kHz :10 (IE
4.5 kHz 110 dB
15 kHz :10 d8
High Filter (Above 10 kHz) 6 dB/Oct.
FUNCTlON TAPE MONITOR ,2,
50 Amp Loudness Contour(100 Hz/ 10kHz) +8 (18/ +4 dB
G'apg'gmfm 6 Hum & Noise (IHF Short Circuit. A Network) _ V
Phono 70 Us
LA 653 LC 4068 5 Tape Monitor 90 dB
Tuner/Auxiliary 90 dB -__
sot-u IkHz A 15km GENERAL
Lo 7315 H 250! I an Power Roqulremenls (50/60 Hz) 120 V AC :10 %
, Power Consumption 330 Watts
AC Outlets 3 --
Tape __
Dimensions (WxHxD) 15-3/4 x4-1/8 x10"
Weight (approx.) 13.5 lbs.
I REC our If

Because Its products are subieot to continuous improvement. Fisher Corporation reserves lhe right to modily
product designs and specifications wllhout notice and Without incurring any obligation

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