Motorola p 6 mw service manual

Page 1

MANUAL 68P43100A75

automofive stereo S-track tape player

BORG-WARNER

MODEL P6MW

automotive stereo 8-trach tape player

MOTOROLA

GENERAL INFORMATION

This underdash 8-track stereo tape
player contains 11 transistors.

WARRANTY SERVICE
STATION PROCEDURE

1. A defective iii-guarantee player
must be accompanied by the Custom-
ers Guarantee Policy Tag. This tag
must be properly filled in by the
Borg-Warner dealer at the time of
the player purchase. Accept as
guarantee repairs only those players
within the 6 month guarantee period.
The removal or re-installation of
this player is customarily per-
formed by the customer and is not
covered by this guarantee. Also,
the removal of motor noise, tire
static, electrical interference and
faulty installations are not con-
sidered as guarantee repairs and,
therefore, expenses related to such
services should be handled by the
customer.

2. Fill in MotorolaGuarantee Labor
Claim, Part Number 68P60016A30,
and mail Green and Pink copies to:

Motorola Guarantee Service
Motorola, Inc,

9401 West Grand Avenue
Franklin Park, Illinois.

3. The yellow copy of the Motorola
Guarantee Labor Claim is to be re-
tained by the authorized service
station for his files.

4. Defective parts for guarantee re-
pairs made on this model are to be
sent to Motorola.

OPERATING INSTRUCTIONS

OPERATION

TO PLAY TAPES - Turn unit on by
inserting a tape cartridge (label
side up and open end first) into the
tape slot. Push the cartridge in
until it is firmly seated. (THIS IS

3-67

service manual

MANUAL 68P43100A75

BORG-WARNER
MODEL P6MW

IMPORTANT.) The tape cartridge
will now play, in succession, all
four channels. Adjust volume, tone
and balance as required.

CAUTION: The tape cartridge
should always be pulled out com-
pletely or approximately 1" from
the seated (play) position before
leaving car.

TAPE CARTRIDGE CARE

To assure maximum life and noise
free operation, tapes should be
stored in a cool, clean and dry place,
out of the rays of the sun and with
the open (tape) end down.

SERVICE NOTES

GENERAL SER

E NOTES

1. POLARITY - WHEN SERVICING
THIS UNIT, THE "A LEAD MUST
BE CONNECTED TO THE POSITIVE
SIDE OF POWER SOURCE. IF CON-
NECTED OTHERWISE, UNIT WILL
NOT OPERATE AND DAMAGE TO
COMPONENTS MAY RESULT.

2. POWER SUPPLY REQUIRE-
MENTS - It is preferable to use a
storage battery (withouta battery

9401 WEST GRAND AVENUE, FRANKLIN PARK,

PRICE 35 CENTS

charger) in place of a battery elim-
inator, If a battery eliminator is
used, it must be well filtered and
regulated.

3. OUTPUT LOAD - Always oper-
ate this unit with an output load
across each of the two channels;
either 8 ohm speakers or 8 ohm, 5
watt resistive loads can be used.

4. TRANSISTOR REPLACEMENT -
When replacing a transistor other
than a power or regulator transistor,
grasp the transistor leads between
transistor body and plated chassis
board with a pair of long nose pliers
to prevent excessive heating of tran-
sistor body during soldering opera-
tion.

5. POWER AND REGULATOR
TRANSISTOR REPLACEMENT -
When replacing a power or regulator
transistor, be sure to:

A. Use the transistor specified
in the Replacement Parts List.

B. Coat both sides of transistor
insulator with DC-4 grease
(Motorola Part No. llM490487)
to insure proper heat dissipation.

C. Securely and evenly tighten
the transistor mounting screws,

MOTOROLA INC.
PART NO. 68P43100A75

I LLI N OI S
COPYRIGHT I967 BY MOTOROLA INC. - PRlNTED IN U.$.A.

Page 2

6. GAINING ACCESS TO THE
PLATED BOARDS - Remove top and
bottom covers and refer to photo.

Tape Pre-Amp Plated Board - To
remove this board for servicing,
merely unsolder the chassis ground
lead (see photo), bend the copper
retaining clip and lift up the chassis
to a more serviceable position.

Audio Amplifier Plated Board - To
gain access to the bottom side of
this board, remove the two (2)
screws at the front side of the radio
(see photo). To remove the board
for servicing, remove the screw
from the mounting bracket, unsolder
the tabs, straighten the tabs, then
remove the mounting bracket.

7. OUTPUT TRANSFORMER AND
FILTER CHOKE REPLACEMENT -
Remove 4 screws, 2 at front side
and 2 at rear (see photo); also un-
solder control ground leads from
Wraparound and pull out wraparound
far enough to remove transformer
or filter choke.

8. TAPE CARTRIDGES - Before
servicing the tape player portion of
this unit, always check for the pos-
sibility of a defective pre-recorded
tape cartridge, particularily if one
is returned with the unit. This
should be done by substituting the
tape cartridge with one that is known
to be good.

9_ TAPE HEAD AND CAPSTAN
CLEANING - One major cause of
improper tape player operation is
oxide build-up on the head and cap-
stan. During normal operation,
some iron oxide particules are
loosened from the tape and build up.
This accumulation of oxide can cause
poor playback and up and down tape
travel. The head and capstan should
be cleaned whenever the unit is ser-
viced and this can be done either in
the car or on the service bench, To
clean the head and capstan, use a
cotton swab moistened with head
cleaner or isopropyl alcohol, then
wipe dry.

(CAUTION should be exercised when
cleaning playback head to prevent
getting cleaner on anyplasticparts.)

10, HEAD DEMAGNETIZING - Do
not use magnetized screwdrivers
and wrenches near the head since
these can magnetize the head. The
head may also, after a long period
of time, acquire some residual mag-
netism, A head that is magnetized
will show a definite loss of high
frequency response and an increase
in noise level. Use a commercially
available head demagnetizer, fol»
lowing instructions included with the
unit to demagnetize the head.

MOUNTING
SCREW

MOUNTING
BRACKET

TABS

AUDIO AMP
CHASSIS REMOVAL

UNSOLDER
2 LEADS

RETAINING

CHASSIS I PRE-AMP REMOVE 4 SCREWS
GROUND PLATED BOARD CLIP
LEAD

FILTER CHOKE 8:
TRANSFORMER REMOVAL

PRE-AMP CHASSIS REMOVAL

GAINING ACCESS TO PLATED BOARDS, FILTER CHOKE
AND OUTPUT TRANSFORMERS

TAPE HEAD ERASER END OF PENCIL

CAPSIAN SHAFT

INIIIII/////////////////X// /////?// ,

TA PE CARTRIDGE
SLOT

USE COTTON SWAB
MOESTENED WITH
ISOPROPYL (RUBENS) ALCOHOL

DEPRESS MOTOR SWITCH
WITH ERASER END OF
DO NOT USE CARBON TETRACHLORIDE PENCIL

TAPE HEAD 8: CAPSTAN CLEANING

ll. HEAD REPLACEMENT - The bly, that is, remove the defective

location of the tape head with respect
to its mounting bracket is very
critical; for this reason, replace-
ment heads are supplied already
secured to their mounting bracket
and positioned correctly at the fac-
tory. When replacing a head, re-
member to replace it as an assem-

head and bracket and replace itwith
the new head and bracket assembly.

If for some reason the location of
the head has changed (due to aloose
mounting screw, etc.), Position it as
shown in Head Positioning Adjust-
ment".