Summary of the content on the page No. 1
GolclStar
MONOCHROME MONITOR
SERVICE MANUAL
WTION
BEFORE SERVICING THE CHASSIS, READ THE “SAFETY
PREtXJTK)NS”, IN THIS MANUAL
MODEL: MBM-2105GIA (MC-3 CHA=W
B GoldStar
Summary of the content on the page No. 2
FEATURES l 2000 display characters in a 8 x 8 dot format. l 18 MHz bandwidth, medium class, composite signal input. l This monitor is compatible with a variety of home and personal computers CONTROLS LOCATION The MBM-2105GIA monochrome monitor uses a RCA jack connector. The input signal is input through the RCA jack connector. The input signal is based on the composite level. Figure 2 shows the monitor controls on the front and rear panels. \ r--- -- [ / t yLcPower Indicator Video In H-Size I Co
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CIRCUIT DESCRIPTION 1. VIDEO AMPLIFIER 2. POWER SUPPLY The Fig. 3 details the cascade video amplifier. The 120V AC line voltage is applied to the primary Video amplification is provided by the TR303 and of the T901 where it is stepped down through the TR304. TR303 and TR304 are connected in a secondary winding to approximately 17V (AC). cascade configuration. TR303 operates as a After passing through the bridge rectifier circuit common emitter and TR304 operates in the and filter (C905) the regu
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Vertical Vetical Frame F,B) Oscillator vcc 2 Vcc 2 Generator Generator 1 Oscillator 1 Vertical output Power Amplifier Input Frame-Synchro Horizontal output Line Fly Back Phase Horizontal Input Detector Oscillator Figure 4, BLOCK DIAGRAM OF THE TEA 2037A 3. COMPOSITE VIDEO INPUT AND HORIZONTAL/ VERTICAL DEFLECTION 3-l VIDEO INPUT (PIN 15) 3-3 LINE (H) OSCILLATOR (PIN 9) The line oscillator is of the type which charges and The detection level for negative sync pulse at the discharges a capacitor,
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ADJUSTMENT 1. REGULATED B + ADJUSTMENT (VRSOl) 5. HORIZONTAL POSITION NR701) Connect high impedance voltmeter between The horizontal position control (VH701) snould be TR901 emitter and ground rotate the B + adjusted for the horizontal picture position. adjustment control (VR901) to obtain a reading of 12.0 2 O.lV. 6. SUB-BRIGHT (VR703) Adjust subbright control (VR703) for visual cut off 2. FOCUS (VR704) of the raster when external brightness is turned to Adjust the focus control (VR704) for bes
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SCHEMA1 CONTRAST VR301 5008 - I - R602 H.V OEFL 15 ..- ! - +y-+$ll.2 TEA2037 4 12.7 TR902 C908 Kltl959-O/Y c905 2200/2! 0901-0904 lN5392GP.4 t- - F901 20.6 T750mA 25OV 1 IUL/CSAI 1315mA25OV A NDE/SEtlKOI 3 MnJ%- 4th H.HOLD u R705 - VR702 33K b.lK 12Ul I 2 u u - NOTES: 1. RESISTORS ARE SHOWN IN OHMS 4 ItlPORTANT SAFETY NOTICE b K = 1.000 M = 1.000.000 THE SYMBOL MARK OF THIS SCHEHATIC DIAGRAM INCOI 2. CAPACITORS ARE SHOWN FEATURES IMPORTANT FOR PROTECTION FROM X-RADIA IN UF OTHERWISE NOTED P : cc
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DIAGRAM 23VI-r IV1 3OvI+ IHI N-i / 9lOKGB3UGREENl mKGB4*wmENl 9lDKMUBLACK/WHTE) 9lDKGB 39 IYELLOWISH GREEN1 5OVP-P M/VI /- - 0 ; H.LW. RltO R719 : b7K 01G.h vR705 R7K 1ooK 2sOKn VR703 EXT. BRIT ;;,2 ,/,6ti cn@ R7u BRJT. FBT 33K &l/l5 f 7701 A R711 l5K R7Y I 1 6.Y , * cm R7OI 1 1 070) c717 lw/ L.wv OwLI/ RGPlOD 100 ‘? loowl tl.OUl c708 20 c7l4 L.7/50 _. 3 !!z’ o%ll l FOilIS 1’05 5 c7l5 u3wl 0.01 / A lK RIM !rl!JE ‘711 6‘3 &lb Lltw (BOOST UP1 \ \ \ & \I-Ln 3Vr-r IHI ‘-- 2oovp+ IH’ 4 IMPORTANT AVIS
Summary of the content on the page No. 8
TROUBLESHOOTING GUIDE TR902, TR903. D905. TR901 AND POWER REG CIRCUIT 7 ~. D706, c713. c714. c715 YES I TROUBLE IN , CHECK CRT (GZ) VOLTAGE 450V NO -, FBT. CR706 R712 2 CHECK CRT (HEATER) VOLTAGE 12V LEAD (HI,. LEAD (Vl, V2) YES ABOVE 55V TROUBLE IN CHECK CRT CATHOD VOLTAGE * TR303, TR304. R311. R309. R310. 45-55v R315, R314, R312 YES HORIZONTAWERTICAL VR703 (SUB-BRIGHT,, R710. R711. “R301 (CONTRAST,, SYNC TROUBLE I VI?,05 (MT BRIGHT,, TRW, TR302. VIDEO CABLE SYNCTROUBLE FIGURE OEBCRIPTION REF.
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PRINTED CIRCUIT BOARD 1. MAIN PCB ASSY PIN: 1 lo-BOW ASSY PIN: ilO-B72A TI J GSEP-2112 BLACK
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3. MAIN PCB (SOLDER SIDE) 4. LINE FILTER PCB (SOLDER SIDE) O-0 Lsol I
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EXPLODED VIEW REPLACEMENT PARTS LIST (MECHANICAL PARTS) , 1ILr.I w 8 1 3X3-A02A 1 COVER ASSY. B& 9 ___ .- 10 407-622A “x-t WNR ruvvcn, 407.696A , I-LAIE., 11 12 303.924A 1 COVER, CRTBOARD I 303.928A [ COVER, PCB SHIELD CASE 1 13 *Outer Cabinet not used on 6300T Models. F E D I C I
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REPLACEMENT PARTS LIST CAUTION: Components identified by the A symbols in the PARTS LIST and on the SCHEMATIC DIAGRAM have special characteristics important to safety. Do not degrade the safety of the set through improper servicing. ABBREVIATIONS: Capacitors . . . . CC: Ceramic (TC), CE: Chemical, CK: Ceramic (Hi-K), BP: Bipolar, CQ: Mylar, PE: Polyester, PP: Polypropylene Resistors . . . . RD: Carbon Film, RS: Metal Oxide Film (All CC and Capacitors are + 5%, 50 Volts and all resistor, +5%, 118
Summary of the content on the page No. 13
DESCRIPTION REMAR REF. NO. PART NO. R C608 CE. 2 2uF 160V R CE. 1OOuF 16V c701 s CO, 0 1uF 1OOV C702 R c 703 CE. 1 OuF 25V COIL R CO, 0 0022uF 1OOV c704 S PP 0 0022uF 200V L301 20-0040 PEAKING PL 4 7uH S c705 R CO, 0 0022uF 1OOV 20-0039 C 706 L302 PEAKING PL 3 3uH S R CQ. 0 015uF 1OOV L701 CHOKE IOuH S c707 R C708 CE, 4 7uF 25V L702 H~LINEARITY S s PP. 0 027uF 400V COIL WIDTH A C709 L703 S R CE, 47OuF 25V L704 20-0038 PEAKING PL 1OuH S CT10 R (1711 CE. 22OuF 16V A L901 LINE FILTER S S BP. 4 7uF
