Scott 355R 375R 385R Service Manual

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Semi-cc Manual
AM/ FM Steieo Receivers

355R 375R 385R

m SCOTT;

The Name to listen to.

H. H. SCOTT, INC.,20 Commerce Way, Woburn, Mass. 01888 Tel. (617) 933-8800

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CONTENTS

PAGE :2"
1. Specifications and revision information.
3. Circuit description, tuner section.
4. Circuit description, tuning indicators.
6. Circuit description, audio amplifier.
7. Circuit description, protection and power meters.
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. Circuit description, temperature sensors.
. Test procedures.

1 . Fluorescent indicator panel lead codes,

14. Parts location diagrams.

17. Circuit diagrams.

20. Exploded view and Notes.

21. Parts list.

32. Troubleshooting guide.

CAUTION NOTICE

The following safety precautions must be followed to assure continued reliability and safety against fire and shock hazard:

l . Replacement parts used during servicing of this appliance must have identical characteristics as those offered and recommended
by H. H. Scott. Inc. In the interest of continued product safety we refer in particulm to those safety critical components shown on
the Replacement Parts List identified by the IEC Symbol A ".

. A dielectric test is to be performed on each appliance following the reassembly and before returning the unit to the customer.
. The dielectric test to be performed on H. H. Scott, Inc. electric components serviced in the United States and Canada for use in
these countries shall consist of not less than the followingz

1) A dielectric tester designed to have an output voltage that (1) has a sinusoidal wave form, (2) has a frequency that is within the
range of 40-70 Hz, and (3) has a peak value of the waveform that is not less than 1.3 and not more than LS times the root-
mean-square value.

la) The sensitivity of the test equipment shall be such that when a 120,000-ohm resistor is connected across the output, the test
equipment does not indicate unacceptable performance for any output voltage less than the specified test voltage, and does
indicate unacceptable performance for any output voltage equal to or greater than the specified test voltage. The calibrating
resistor is to be adjusted as close to 120,000 ohms as instrumentation accuracy can provide, but not more than 120,000 ohms.
The tester is to be connected per the instructions enclosed with the instrument, or as follows:

. The tester is connected to the power line receptacle and the power switch is turned on.
. Sufficient time is allowed for the tester supply to stabilize and then the output voltage is adjusted for 1080 V.
. Leads of the tester, usually marked GND and HV, are connected between chassis ground and both blades of the male
plug of the power cord.
d. Switch tester to test and observe leakage indicator.

*Dielectric tests made by service personnel in countries other than USA and Canada must use test equipment and procedures
specified by the safety agency serving that country.

COPYRIGHT [Ll-l. SCOTT ELECTRONICS®
Printed in um. um 0294175049 ,5 _
it

HH. SCOTT ELECTRONICS®, Scottkit' and 5:0 ls ma nv are
registered trademarks of H.H. SCOTT, Inc.

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REPLACEMENT LIST OF MECHANICAL AND ELECTRO MECHANICAL PARTS-
REFER TO 385R EXPLODED VIEW

.2",

SYMBOL PART NO. DESCRIPTION SPECIFICATION USED IN
1 6102-5028101 CABINET 1.0T VINYL STEEL ALL
2 6103-500-3107 SIDE-CABINET-L lST PLYWOOD VINYL ALL
3 6103-500-4102 SIDEvCABINET-R 15T PLYWOOD VINYL ALL
4 7334-500-1 106 WASHER-CABINET P.P BLACK ALL
5 6804-502-2206 SPACER-CABINET 1.0 HIMERONE SHEET ALL
6 6022-505-6107 CHASSIS-BOTTOM 1.0T SPC-l FZY ALL
7 6074-500-2101 FOOT RUBBER ALL
8 7702-507-7100 PANEL»FRONT AL EXTRU 355R
8 7702-507-7207 PANEL-FRONT AL EXTRU 375R
8 7702-507-7304 PANEL-FRONT AL EXTRU 385R
9 6463-500-7106 GUIDE-KNOB F ABS GREY ALL

10 7714-504-7207 PLATE-BACK VOL. 0.8T ALS ALL
11 7603-502-1109 MASK-TUNING ABS GREY ALL
12 7724-507-7104 KNOB-TUNING ALB ALUMITE ALL
13 7724-505-6103 KNOB-ROTARY ALB ALUMITE ALL
14 7724-506-0106 KNOB-BALANCE 94HB ACRYL CLR ALL 1
15 7724-503-7108 KNOB-VOLUME ALB ALUMITE ALL
16 7653»501-4106 DIAL WINDOW 5.0T ACRYL CLR ALL
17 8012~504-1106 SCALE-DIAL 0.5T ALS OFFSET 355R
17 8012-504-1203 SCALE-DIAL 0.5T ALS OFFSET 375R
17 8012-504-1300 SCALE-DIAL 0.5T ALS OFFSET 385R
18 8014-502-7104 BLIND-SCALE ACRYL 0.5T X 373 X 13 ALL
19 8012-504-0208 SCALE-BACK 1.0T SPC-l MET GRY 355R
19 8012-504-0101 SCALE-BACK 1.0T SPC-l MET GRY 375R
19 8012-5040305 SCALE-BACK 1.0T SPC»1 MET GRY 385R
20 6834-506~6103 SPACER RUBBER 3.5T ALL
21 8003-5130-4101 CAP-POINTER ABS BLK ALL
22 7654-503-3104 FILTER-WINDOW ACRYL 0.5T 355R
22 7653-5113-0102 FILTER-WINDOW ACRYL 0.5T 375R
22 7653-503-0209 FILTER~WINDOW ACRYL 0.5T 385R
23 0859-141-6008 TEFLON TAPE W 25.4 X 33Y >< 0.8T ALL
24 6613-506-1105 BRKT-GUIDE PNTR 0.8T SPCY-1 FZW ALL
25 5104-509-1100 SHAFT-TUNING MB R2 GCIO ALL
26 6603-500-6107 HOLDER-LED,S ABS NATURAL ALL
27 6614-5153-2106 BRACKET, SCALE, R 1.0T SPC-1 FZW ALL

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FUSES

SYMBOL PART NO. DESCRIPTION SPECIFICATION USED IN
F505 4709-0314004 FUSE NOR 125V 6A, 31, 8 UL 375R, 385R A
F505 4709-0311-3106 FUSE NOR 125V 5A, UL 355R A
F801 4709-1133-1402 FUSE W/ LEAD SLO 125/250 0.5A UL ALL A

F501, F502

F503, F504 4709-1311-3309 FUSE W/LEAD NOR 125V, 8A UL ALL A

INTEGRATED CIRCUITS

SYMBOL PART NO. DESCRIPTION SPECIFICATION USED IN
IC701 2119-101-4500 [C TA 7318P 385R
[C806 21 19-201-1300 [C-DISPLAY LC 7555 355R, 375R
[C702 2119-201-3203 [C-DISPLAY LC 7556 385R
IC101 2119-201-0907 IC-AM IF HA 1197 ALL
[C201 2119~201-0402 [C-FM [F HA 1137W ALL
IC30l 2119-201-1106 IC-MPX HA 1196 ALL ~25

[C901, IC951 2119-4010206 [C-OP TA 7322P ALL
[C401, [C451
[C801 2119-601-0301 IC-REG LA 5700 375R, 385R A
[C802 2119-601-0204 IC-PRESCALER SP 8629 375R, 385R
IC803 2119-201-[203 [C-FREQ. DISP. LC 7258 375R, 385R
[c804 2119-401-0303 IC»OP NJM 4558 DD ALL
[C805 2119-201-2004 IC-SIG BA 6104 ALL

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