Marantz 1200 Service Manual 2

Page 2

WW TROUBLE ANALYSIS

The following section is designed to assist in locating troubles. The information given is to help in
situations where problems may be difficult to isolate. Any field problems that arise will be covered
through service bulletins (supplementary to this manual) that will be issued to all service stations. it is
assumed that normal trouble-shooting techniques (i.e. point-to-point signal tracing, oscilloscope analysis,
etc.) will be used to isolate problems.

NOTE: Performance verification is
necessary following any repair.

SYMPTOM PROCEDURE
1. Excessive line consumption (100 watts or a. Check for shorted rectifiers CR601 through
more). gR604, CR701 through CR704, CR705 and
R706.

13. Check for shorted transistors 0802 through
0805, 0507, 0508, 0510, 0511. Check for
open control R526, 215-1005-1 bias assy.
Check T1 for short.

CAUTION: Because the driver and output stages are direct coupled, components may fail as a direct result
of an initial component failure. If a shorted semiconductor is found, be sure to check the remaining
driver and output components for short or open circuits before re-energizing the amplifier. After
replacement of any of these components, increase the Variac voltage slowly while monitoring the watt-
meter as described in paragraph C of Performance Verification.

2. No line consumption or zero bias. a. Check line cord, fuse, transistors 0507, 0508,
0510, 051 1, 0802 through 0805, shorted 215-
1005-1 bias assy.

b. Check for open rectifiers CR601 through
CR604, CR701 through 704, CR705 and
CR706, or open T1.

3- High (30 voltage at loudspeaker terminals a. Check transistors 0701 through 0703 for
before time delay circuit is activated. leakage, shorted, or open.

a. Check R701 through 705 for open and 0701
for leakage, or open. Check for shorted or

open transistors 0802 through 0805, 0507,
0508, 0510, or 0511.

4. High d-c voltage at loudspeaker at all times.

5. No D-C Balance.
a. Check 0501, 0502, R502, and Zener diodes
CR501, CR502 (amplifier). Check 0205,
0206, 0201, 0202, R235, and R214 (pre-
amplifier).

b. Check R501, R503 (amplifier).

Page 6

PARTS LIST

3:35:32" Description and/or Remarks raiiamizmber 3:35:32 Description and/or Remarks giiaasmber
L501 Toroid 147-1007 R517 Res, W/W, 1.2K,110%, 2w 436-4123
0501 Cap., 150pf,110%, 100v 385-1038 R513 Res" W/W' 12K'i1°%' 2 4364123
0502 Cap. Elect 10qu 25v 381-1034 R519 Res. Prec., 20K, 11%, %w 431-5200
6503 Cap. Elect. 1001,25v 3814034 R520 Res, C/F, 100K,15%, %w 434-6102
0504 Cap. Elect" 100 1, 25v 381-1 034 R521 Res, C/F, 300 ohm, 15%, %w 434-3302
0505 Cap" 47pr 110%, 100v 3854 040 R522 Res, C/F, 560 ohm, 15%, %w 433-3562
0506 Cap 680pf, 15%. 100v 3854042 R523 Res, C/F, 560 ohm, 15%, %w 433-3562
0507 Cap. Elect, 22001, 6.3V 381-1044 R524 Res" C/F' 27"! 15% W 4345272
0508 Cap.,36 121.15%, 100v 385-1064 R525 Res" C/F' 27K' i5%' W 4345272
0509 Cap., 36pf, i596, 300V 385-1018 R526 Res, Variable, 1K, 2W 420-1011
0510 Cap., 0.101, 110%, 250v 386-1000 R527 Res" E 47 °"' 5% VZW 4334472
0511 Cap 01qu 110%, 250v 385-1000 R528 Res., C/F, 47 ohm, 15%, '/2W 433-2472
0512 Cap., 410pr 110%, 100v 3854055 R529 Res, 0/0, 39 ohm, 110%, 1w 423-2392
0513 (3351., 0220011011., 250v 385-1017 R530 Res" (Q 39 °hm' 0%" N 4232392
0514 Cap., 1600pr $1070, 300v 3854020 R531 Res., wIw, 0.1ohm,15%, 5w 145-1002
0515 Cap 1600pr i10%, 300v 38511020 R532 Res., W/W, 0.1 ohm, 15%, 5w 145-1002
0516 Cap 0.101,110%, 250v 3864000 R533 Res.,W/w,0.15ohm.110%,5w 428-0153
0517 Cap" 10qu 120%, 100v 3884001 R534 Res..W/w, 0.15 ohm,110%, 5w 428-0153
0518 Cap., 13001,110%,300v 385-1019 R535 GS"W/W'o'15°hm'im%'aw 42843153

R536 Res.,W/w,o.15ohrn,110%,5w 428-0153
501 Dim" zen 4594006 R537 Res., C/F, 330 ohm, 15%, %w 434-3332
CR502 Diode, Zener 459-1006 R538 Res, C/F, 330 ohm, 15%, %W 434-3332
R501 Res., C/F, 7.5K,15%, yew 433-4752 R539 Res, C/C, 27 ohm, 15%, 2w 424-2272
R502 Res., Variable, 2K, 2w 420-1000 R540 Res, C/F, 2.2K,15%. %w 4334222
R503 Res, C/F,4.7K,15%,1/2W 433-4472 R541 Res., Variable, 2.5K, %w 420-1019
R504 Res., C/F, 100K,15%, .%w 434-6102 R542 Res, Variable, 2.5K, %w 420-1019
R505 Res., C/F,470K,15%, %w 434-6472 R543 Res., C/F, 2.2K,15%, %w 433-4222
R506 Res, C/F, 1K,15%, %w 434-4102 R544 Res, C/F, 1 K, 15%, %w 433-4102
R507 Res, C/F, 100K,15%, %w 434-6102 R545 Res, C/F, 1 K, 15%, %w 4334102
R508 Res., C/F, 7.5K,15%, %w 433-4752 R546 Res., BWH, 1.0 ohm, 15%, 2w 435-1102
R509 Res, C/F, 3.3 K, 15%, %w 434-4332 R547 Res., C/F, 2.2K,15%, %w 434-4222
R510 Res., C/F, 8.2K,15%, '/4W 4344822 R548 Res., C/F, 2.7K,15%, %w 434-4272
R511 Res., C/F, 680 ohm, 15%, %w 434-3682 R549 Res., C/F, 10K, 15%, %w 434-5102
R512 Res., C/F, 7.5K,15%, yew 433-4752 R550 Res, C/F, 1K, 15%, %w 434-4102
R513 Res. Prec., 1K, 11%, %w 4314100 R551 Res., C/F, 270K, 15%. %W 434-6272
R514 Res, C/F, 2K, 15%, 1/4W 4344202 0501 Transistor, NPN 4624038
R515 Res, C/F, 27 ohm, 15%, %w 433-2272 0502 Transistor, NPN 462-1038
R516 Res., C/F, 220 ohm, 15%, %w 434-3222 0503 Transistor, PNP 461-1037

Raffwn'i" Description and/or Remarks Marantz Referenee Description and/or Remarks Maran
DeSlgnatlon Part Number Des19natlon Part N
0504 Transistor, NPN f 462-1044 0612 Cap Elect, 680uf, 16V 331.
0505 T 'r PNP 4 1-1036
0 rams or' 11 6 0R501 Diode 460.
506 T ' NPN . .
O ransastor, 462 1042 CR 602 Diode 460-
507 T ' t PNP . .
"mm or , 461 1003 CR603 Diode 450.-
0508 T I NPN , .
5 °r' 1 4621004 0R804 Diode 460-'
0509 Not used ' ,
O , CR605 Diode, Zener 4594
510 T 't NPN 4 .14
ranSIs or, , 62 0 O CR606 Diode, Zener 459-
0511 Transistor, PNP 451-1034
0512 Not used R601 Res-. C/F. 10 ohm,:5%, 14w 433-2
1
0513 Not used 1 R602 Res, c/F, 10 ohm, 15%, /2W 433.2
0514 Not used 1 R603 Res., C/F, 10 ohm, 15%, %w 433.;
0515 Not used R604 Res, 0/F, 10 ohm, 15%, 1/2W 433-2
0516 Transistor, NPN . 462-1035 R505 Res-r C/F' 24" °hm- i5%- W 433-2
0517 Transistor, PNP 1 451.1030 R606 RES-r C/F- 750 ohm. i5%. W 433-:
0518 Transistor, PNP 2 461-1013 R507 Res-r C/F' 75° °hmv i596, %w 433?
0519 Transistor, PNP 1, 461-1013 R608 Res., C/F, 240 ohm, i5%, '/2W 433.3
0302 Transistor, pr 461-1031 R609 Res., C/F, 200 Ohm, 15%, '/2W 433.3
0803 Transistor, NPN 462-1036 R510 Res-r C/F- 20° 0W"- i5%- W 4335
0804 Transistor, PNP 461-1031 R6 Resu C/F- 20 ohm- i570- 72" 433-2
0805 Transistor, NPN ,46221036 R612 Res C/F. 120 ohm, 15%.1/2w 433.3
0801 Cap., 0.101, 110%, 250v 386-1000 0501 angst: NPN 452"
0602 Transistor, PNP 461~1
CR801 Diode 460-1011
0801 Transistor, NPN 462-1043 RECT' HER/RELAY BOARD
COMPONENT ASSEMBLY
Heat Sensor Assy. :215-1006-1 C701 Cap. Elect, 22qu 25V 381-1
POWER SUPPLY BOARD 0702 Cap. Elecr., 22001, 6.3V 381-1
COMPONENT ASSEMBLY I 0703 Not used
0501 Cap. Elect, 47001, 40v 381-1022 0704 Not used
C602 Cap. Elect, 470uf, 40V 3381-1022 C705 Cap. Elect, 22qu 63V 381-11
0603 Cap. Elect, 47001, 40v 1381-1022
r 0R701 Diode 460-1(
0504 Cap. Elect, 10001, 40v 1381-1013
. CR702 Diode 460-11
0605 Cap. Elect, 10001, 40v ,381-1013
- 0R703 Diode 460-1(
0606 Cap. Elect, 47001, 40v 1381-1022
, 0R7o4 Diode 460-1(
0807 Cap. Elect, 47001, 40 v 1381-1022
- 0R705 Diode 460-1c
C608 Cap. Elect, 47001, 40v 381-1022
1 CR706 Diode 460-11
0609 Cap. Elect, 68001, 16v ,381-1008
1 CR707 Diode, Zener 459-11
0510 Cap. Elect, 6800i, 15v 381-1008
0611 Cap. Elect, 680uf, 16V 381-1008 Chassis, Fastener 568-1c