Dumont RA-306, Service Manual

Page 1: ... Cont Trans Inductor Alignment Identification 21 Resistance Measurements 8 Servicing in the Field 18 Schematic Alternate Tuner 7 Schematic TV 2 Trouble Shooting Aids 12 17 Tube Failure Check Chart 5 Tube Placement Chart Bottom View 8 Tube Placement Chart Top View 5 o o s CO O HOWARD W SAMS CO INC Indianapolis 5 Indiana The listing of any available replacement part herein does not constitute in any...

Page 2: ...RF AMP 6BK7 THE COOPERATION OF THE MANUFACTURER OF THIS RECEIVER MAKES IT POSSIBLE TO BRING YOU THIS SERVICE PAGE 2 ...

Page 3: ...A PHOTOFACT STANDARD NOTATION SCHEMATIC Howard W Samj 8 Co Inc 1954 ...

Page 4: ... RII LINEARITY ClOT p DO NOT MEASURE ...

Page 5: ... DEFLECTION YOKE VERT 45 HORIZ PICTURE TUBE 121FP4A DUMONT MODELS RA 3O6 RA 3O7 ...

Page 6: ...DUMONT MODELS RA 306 RA 3O7 en I U ...

Page 7: ...CHASSIS BOTTOM VIEW CA PAGE 4 ...

Page 8: ... APACITOR IDENTIFICATION PAGE 9 ...

Page 9: ... OR SOUND No pic no sound has raster V3 V4 V5 V6 V7 V8 V13 VI UHF only No pic no sound has snow V2 V3 V4 No pic has sound has raster V8 V24 Has pic no sound V10 Vll V12 V13 Overloaded picture V9 V12 SYNC FAILURE No vert sync V15 V16 No horiz sync V15 V17 V18 No vert or horiz sync V14 V15 SWEEP FAILURE No raster has sound V18 V19 V20 V21 V24 Fuse Ml No vertical deflection V15 V16 Poor vert linearit...

Page 10: ...50KC sweep Use L2LH sawtooth voltage in scope for horizontal deflection DUMMY ANTENNA Direct SWEEP GENERATOR COUPLING High side to point Low side to chassis SWEEP GENERATOR FREQUENCY 4 SMC 450KC Swp MARKER GENERATOR FREQUENCY 4 SMC CHANNEL Any CONNECT SCOPE Vert Amp to point OT Low side to chassis Vert Amp to point N Lowside to chassis SOUND IF ALIGNMENT USING ADJUST A10 A11 A12 REMARKS Disconnect...

Page 11: ...A PHOTOFACT STANDARD NOTATION SCHEMATIC Howord W Samt Co Inc 1954 270V A L T E R N A T E VHF TUNER PARTNO 890l297l1 USED ON SOME MODELS ALTERNATE TUNER SCHEMATIC UHF TUNER PAGE 7 ...

Page 12: ...on in f265n on in on on 70Kn s ucn INF HAVE 24n 24n PIN 10 s sxn Pin 5 5 6Kf on 190Kn 470n i470n 470n 2 2Meg on 540Kn iKn i5Kn 1 4M6K tseoKn 30Kn in in 4 8Meg t270Kn 470Kn tssn INF INF INF PIN 11 UQDKa_ Pin 6 5 6Kn f3 2Kn WKn T13KS1 ti3Kn i470n 3 3Kn in t45n iiKn on 900Kn fioOKn i22Kn 2 5Meg 2 2Meg on i SKn INF INF RESISTANC 24n 24n PIN 12 in Pin 7 on 470Kn on on on on sn t7 iKn ts iKn 220n i5Kn t...

Page 13: ...VHP TUNER RIGHT SIDE VHP TUNER BOTTOM VIEW PAGE 10 ...

Page 14: ...chingoff channel and back again Picture should pull into sync If picture does not pull into sync readjust Bl slightly until picture pulls Into sync Repeat procedure until proper pull in is obtaine d Adjust the horizontal width slug B2 for a picture that is slightly wider than necessary to fill the picture mask horizontally Adjust the horizontal linearity slug B3 for a picture that is symmetrical f...

Page 15: ...re or change of value LOSS OF VERTICAL SYNC HORIZONTAL SYNC SATISFACTORY Check by substitution V14 and V15 Check waveform W8 If Satisfactory If Unsatisfactory Check components associated with V15B Check vertical integrator and other associated components Check video IF stages for overloading LOSS OF HORIZONTAL SYNC VERTICAL SYNC SATISFACTORY Check by substitution V17 and V18 Check waveform W13 If ...

Page 16: ...ociated R122 andother associated circuit circuit components components Check by substitution V18 V19 V20 V21 V22 and V23 Check T2 T4A R122 R121 R118 C4 picture tube and other associated components GENERAL RASTER SOUND NO PICTURE Follow procedure outlined under Loss of Video RASTER PICTURE NO SOUND Follow procedure outlined under Weak or No Sound RASTER NO SOUND NO PICTURE Check V2 V3 V4 V5 V6 V7 a...

Page 17: ...3124770 03119170 03124790 03125500 03119170 03019840 03019840 03126010 03126010 03124790 03125500 03125110 0312 5110 03125000 03125600 03100490 03100490 03015610 03137300 03100490 03012150 03131320 03015610 03122800 03017850 03121520 03017850 03017850 03121520 03121560 03121520 03017850 03100490 03014610 AEROVOX PART No AFH2 64 1 PRS450 40 AFH3 41 PRS50 10 E26D190 PRS450 4 PRS150 4 EF 001 BPD 0008...

Page 18: ...HAFTS B13 137 Pl 028 Panel Bll 141 R12 108 Rear Note 1 Connect a 47KO resistor in series with the left hand terminal of the control and the lead connecting to the same terminal of the original control control viewed from shaft end terminals down ITEM No H9 RIO Rll R12 R13 R14 R15 RIG R17 R18 R19 R20 R21 R22 R23 R24 R25 R26 R27 R28 R29 R30 R31 R32 R33 R34 R35 R36 R37 R38 R39 R40 R41 R42 R43 R44 R45...

Page 19: ...2660 02032580 02031130 02032010 02031160 02038380 02031950 02032100 02031910 02032050 02032170 02037930 02032010 02031950 02032600 02030440 02031780 02030440 88000631 02032120 02031770 02032140 02034070 02034990 02030760 02032620 02034760 02034970 02031740 02031740 02058490 02032010 02032010 02032210 02032110 02034540 02030540 02030700 02032010 02032060 02032000 02032060 02032670 02032350 02032580...

Page 20: ...onnections 9 NC 4 3 1 IS 3 a Triad Connections 9 8 7 NC 4 3 1 1 3 RCA Connections 9 8 7 NC 4 3 1 1 3 Holldorson Connections 9 NC 4 3 3 0 Thordarson Con neclic ns 9 8 7 NC 4 3 1 Id3 TRANSFORMER AUDIO OUTPUT ITEM No T7 IMPEDANCE PRI 2 8KO SEC 3 5O REPLACEMENT DATA DUMONT PART No 902492 2 Stancor PART No A 3849 CD Merit PART No A 3018 CD Triad PART No S 4X CO PART No Z1005 PART No T 26S50CD NOTES CD ...

Page 21: ...ohenries 197 Micrhhenrles 500 Microhenries Tertiary windings 7n 82 Microhenries IRC Part CLA 4 7Mlcrohenries IRC Part CL 1 2 2 Microhenries IRC Part t CLA 2 2 Microhenries IRC Part CLA t Disconnect R29 when used as replacement FILTER CHOKE ITEM No L41 RATINGS TOTAL DIRECT CURRENT 240ADC D C RESISTANCE 44 6n INDUCTANCE 0 CURRENT 1000 Vl 2HY REPLACEMENT DATA DUMONT PART No 21010951 Stancor PART No C...

Page 22: ...USTMENT Adjustment of the Horiz Oscillator Circuit can be made from the rear panel of the chassis Set the Horiz Hold Control at the Mid position of its range and adjust the Horiz Osc slug until the picture synchronizes horizontally SOUND IFDETECTOR BUZZADJUSTMENT To eliminate Sound IF Detector Buzz adjust the Ratio Detector Secondary L35 located on top of chassis See tube placement chart FUSES One...

Page 23: ...CHASSIS BOTTOM VIEW RESISTC PAGE 19 ...

Page 24: ...A VIEW RESISTOR IDENTIFICATION PAGE 20 ...

Page 25: ...CHASSIS BOTTOM VIEW TRANS INDUCTOR AND ALIGNMENT IDENTIFICATION PAGE 21 ...