Pioneer m 91 service manual

Page 1

GD PIONEER

Sefiice /

(71451111131 !_____ . ORDER N0.
_. .. ARP1 634

STEREO POWER AMPLIFIER

M-Q'I

M- 90a

M-91 AND M-90a HAVE FOUR VERSIONS:

E
[i

Applicabla modal
M-91 M-SOa
-- AC120V only U.S.A. and Canada
AC220V,240V Iawltchabia) European continent
ACZZOV,240V Iawitchebia) United Kingdom
ACZZOV,24OV (awitchabial' West Geramany

Power taqukamant Duthatlon

'Change the pIimaty writing of the power ttanaformor

0 This manual is applicable to the M-91/KU/CA, M90a/HE,HB and HEZ types.
0 For the MSOaIHE,HB and HEZ types, refer to page 24.

CONTENTS
I. SAFETY INFORMATION ------------------------ 2 5. SCHEMATIC DIAGRAM ------------------------ I5
2. EXPLOOEO VIEWS AND PARTS LIST ------ 3 6. P.C.BOAROS CONNECTION
2.I Exterior .......................................... 3 DIAGRAM .......................................... I9
2.2 Interior .......................................... 6 7. FL DISPLAY INFORMATION .................. 23
3. PACKING ............................................. 9 8. FOR MSOa/HE HB AND HEZ TYPES ...... 24
4. ELECTRICAL PARTS LIST --------------------- I0 9. PANEL FACILITIES ------------------------------ 29
I0 SPECIFICATION ................................. 30

PIONEER ELECTRONIC CORPORATION 4-1, Meguro i-Chome, MegurO-ku. Tokyo 153. Japan

PIONEER ELECTRONICS SERVICE INC. PO Box 1760, Long Beach. California 90801 USA.

PIONEER ELECTRONICS OF CANADA. iNC. 505 Cochrane Drive. Markham Ontario L3R 863 Canada

PIONEER ELECTRONIC [EUROPE] N. V. Keetberglaan 1 2740 Beveren, Belgium

PIONEER ELECTRONICS AUSTRALIA PTY. LTD. 178-184 Boundary Road. Braeside. Victoria 3195. Australia TEL: [031580-9911

PIONEER ELECTRONIC CORPORATION 1988 Y0 JULY 1989 Printed in Japan

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1. SAFETY INFORMATION

1. SAFETY PRECAUTIONS

The following check should be performed for the
continued protection of the customer and service tech-
nician.

LEAKAGE CURRENT CHECK

Measure leakage current to a known earth ground
(water pipe, conduit, etc.) by connecting a leakage current
tester such as Simpson Model 229-2 or equivalent between
the earth ground and all exposed metal parts of the appli-
ance (input/output terminals, screwheads, metal overlays,
control shaft, etc.). Plug the AC line cord of the appliance
directly into a 120V AC 60Hz outlet and turn the AC
power switch on. Any current measured must not exceed
0.5mA.

.3...- Reading should

0
not be above

Leakage

Device current 0.5mA
under Tester
test ' '

Test all

exposed metal

surfaces

2-wire cord

@ Also test with
plug reversed Earth
(Using AC adapter grOund
plug as required)

AC Leakage Test

ANY MEASUREMENTS NOT WITHIN THE LIMITS
OUTLINED ABOVE ARE INDICATIVE OF A PO-
TENTIAL SHOCK HAZARD AND MUST BE COR-
RECTED BEFORE RETURNING THE APPLIANCE
TO THE CUSTOMER.

2. PRODUCT SAFETY NOTICE

Many electrical and mechanical parts in the appliance
have special safety related characteristics. These are often
not evident from visual inspection nor the protection
afforded by them necessarily can be obtained by using
replacement components rated for voltage, wattage, etc.
Replacement parts which have these special safety charac-
teristics are identified in this Service Manual.

Electrical components having such features are identified

by marking with a ". on the schematics and on the parts
list in this Service Manual.
The use of a substitute replacement component which
dose not have the same safety characteristics as the
PIONEER recommended replacement one, shown in the
parts list in this Service Manual, may create shock, fire.
or other hazards.

Product Safety is continuously under review and new
instructions are issued from time to time. For the latest
information, always consult the current PIONEER Service
Manual. A subscription to, or additional copies of, PIONEER
Service Manual may be obtained at a nominal charge from
PIONEER.