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66KS3700 / SIERRA [TV 70-74 (66-70) cm picture]

The EURAS repair tip database for professional technicians and service engineers supplies the following faults for 66KS3700 / SIERRA.

List of fault symptoms:
  • Picture like when there is loss of channel and recovery. No sound. (extract of circuit diagram attached)
  • Defective infra red control.
  • Station search runs through stations, Stop command present.
  • No RC functions (intermittently).
  • Loss of tuning point after operating for some hours. (66KS3700 tips)
  • LED display is distorted. No control.
  • Distorted audio. (extract of circuit diagram attached)
  • Teletext information moves. (66KS3700 SIERRA repair tip)
  • Connection of a loop system to the TV. (66KS3700 tips)
  • Appliance switches off and back on when swift increase/decrease of voltage occurs.
  • Horizontal lines in the picture and the colour sways.
  • 2-3 flyback lines in top of picture. (+ extract of circuit diagram)
  • With "scan" playback of VLU plates, rattle on appliances with mute switching. (with circuit diagram extract)
  • Picture is very dark, looks like a low voltage on CRT. (extract of circuit diagram attached)
  • Dead. Comes on in standby if switched on at mains plug and if made to come out of standby by pressing on/off switch the standby light goes off. (66KS3700 tip from SIERRA)
  • White screen. Flyback lines. Fault occurs intermittently. .
  • No vertical deflection. (extract of circuit diagram attached)
  • + 140 V present, no H.T.
  • Error codes. (part of circuit diagram displayed)
  • Only snow in picture. After pressing cassette player channel no. appears but snow remains. Tuning voltage is 33V.
  • No colour (intermittently). (picture attached)
  • Low picture amplitude. Approx. 3cm wide black edge on top and at the bottom.
  • Contrast problems. (part of circuit diagram displayed)
  • Snow in picture.
  • Too bright. Coloured flyback.
  • Switches to standby.
  • The picture pulls on the upper side of the picture. (picture attached)
  • Video is missing, small amount of chroma. (picture attached)
  • Service tips for Japanese VCRs.
  • Line problems. (+ extract of circuit diagram)
  • Loss of display when switching over. Returns but disappears again after a few mins.
  • The picture briefly disappears.
  • Interference caused by rays from medium wave band transmitters. (+ extract of circuit diagram)
  • Change from TRD to TRD-ECO.
  • Blank screen. High voltage and display OK.
  • Excessive brightness. No picture. Retrace lines.
  • Frame rolls, jitters or picture unstable. (part of circuit diagram displayed) (service info for SIERRA -66KS3700)
  • On some channels when appliance is in mono it switches to stereo for a short time or audio channel 2 has a lot of audio interference. Repeats in irregular intervals.
  • No channel search. Display OK .
  • Faint flyback line. (part of circuit diagram displayed)
  • Clock problems. (SIERRA - 66KS3700 information)
  • Flickering picture. (picture attached)
  • The letters tip over during video text.
  • Tripping. intermittently. Pincushion distortion. on sides. (picture attached)
  • No picture. No audio. Fault occurs intermittently. .
  • No start-up.
  • Replacement for U341 tuner.
  • After playing for some time, picture goes dark (2-3 times per evening).
  • Automatic tuning does not stop when finding a station, although it scans bands ok. (extract of circuit diagram attached)
  • Intermittent low gain.
  • Teletext faulty. replaced 2 text IC's now text on screen but picture still visible in background with grid effect.
  • + 140 V not present.
  • Line output transistor (BU208A) fails.
  • Venetian blind effect. (picture attached)
  • The appliance loses all the stored stations, works without the battery. (66KS3700 tips)
  • Incorrect teletext character height.
  • Distorted picture. (picture attached)
  • Electronic protection responds.
  • Replacement of tuner ECL2006 with UV418.
  • Went up in smoke.
  • No picture. after a while. Audio OK .
  • Picture rolls in at the bottom. Vertical lienarity error.
  • No switch from TXT mode to TV mode and TXT picture appears excessive. (extract of circuit diagram attached) (service info for SIERRA -66KS3700)
  • Disconnection from the operating unit - chassis.
  • Poor or slow search.
  • Picture too small. (part of circuit diagram displayed)
  • Hiccups from PSU when fluorescent light is switched on/off.
  • Interference on channel 2 with TRD4 system.
  • The picture turns blank, the sound sometimes disappears caused by TXT. (66KS3700 SIERRA repair tip)
  • Picture shifted horizontally. (with circuit diagram extract) (66KS3700 tips)
  • Resistor R303 (2.2 Ohm) blows continuously.
  • Increased picture width. Sideways distortions.
  • No start-up. intermittently.
  • Creaking.
  • Does not stop on K5 and/or K21 in search mode.
  • Blank raster. Audio OK . (extract of circuit diagram attached)
  • Memory loss. at switch-off.
  • Flashing picture. Picture too small.
  • Squealing noise. (with circuit diagram extract)
  • Does not change channels. No audio.
  • Horizontal lines run through the picture with playback of the VP 720 scart.
  • Intermittently switches to STEREO or second language.
  • The operation functions do not function The display functions.
  • For initial 10 minutes the picture is dark. (with circuit diagram extract)
  • Horizontal shaking. after start-up.
  • The cable television picture rattles on several stations (during VHF or UHF or on both channels).
  • Picture has strong "Moire" interference.
  • Insufficient brightness when switching on. Shortly after, becomes brighter (looks like bad CRT).
  • Reduced vertical deflection.
  • Horizontal jitter.
  • The picture is streaky and there is no UHF reception in high ranges.
  • No contrast control.
  • Zigzags. IC 3571BQ does not meet specifications. (part of circuit diagram displayed)
  • Defective vertical deflection (oscillograms missing on the V deflection unit). Dark picture. (with circuit diagram extract)
  • On different channels the video tuner sound is missing. Sometimes the sound is present for a short time and then fails.
  • Blurry picture. Audio OK .
  • Dark screen, blank if brightness is increased.
  • After it has been switched on the TV switches off then switches on again, picture is faded (green). EHT discharge.
  • Vertical collapse. (picture attached)
  • Display initially shows 1, then E1 and E0 at switch on. Noise in picture and no control when EO in display.
  • Blank raster. Searches for channels continuously.
  • No TXT.
  • Three types of line transformers. (SIERRA - 66KS3700 information)
  • E/W fault. Excessive horizontal size.
  • Picture shadow a little to the right of the real picture. Visible before with test picture. Vertical raster lines cast a clear shadow on the left and right side of the circle, also with subtitling.
  • Slow warm up, first five to ten minutes picture dark with a restricted brightness control range. (with circuit diagram extract)
  • No sound. Picture cramped by 5cm up and down.
  • Teletext lines disappear (about 9 lines). (with circuit diagram extract)
  • Smoke from air vents in back cover at switch on. (service info for SIERRA -66KS3700)
  • Reduced vertical size. (with circuit diagram extract)
  • Excessive brightness. Flyback lines (intermittently). (part of circuit diagram displayed)
  • Extension print (SBC 312).
  • Picture tube A37-570X.
  • Intermittent colour. (part of circuit diagram displayed) (66KS3700 tip from SIERRA)
  • Height problems. (+ extract of circuit diagram)
  • Line output transformer information.
  • Protection circuit active (set hiccups). (SIERRA - 66KS3700 information)
  • The TV switches on regularly after which the raster appears only with a snowy effect. On the screen there are also horizontal white bands. Tuning voltage is blocked. (SIERRA - 66KS3700 information)
  • Fuse 2A on rectifier module goes defective after around 4-6 weeks. This always happens when switching on a VH appliance.
  • Dark picture.
  • Jamming on vertical lines when switching set on in cold conditions. Visible with crosshatch pattern or with pattern lines.
  • Store standard values.
  • Replacing prescaler module U18.
  • Other frame problems. (with circuit diagram extract) (service info for SIERRA -66KS3700)
  • No picture, no sound, high voltage and the display indication is present.
  • + 12 V on pin 10 of U2 not present. (SIERRA - 66KS3700 information)
  • No E/W correction. (with circuit diagram extract)
  • Faint flyback lines plus shading at one side.
  • Picture is cut off at the bottom and black bar.
  • No picture. (picture attached)
  • TXT reception problems with K30/K35 chassis. (part of circuit diagram displayed)
  • Vertical lines.
  • Set won't lock to channels in the search tuning mode, with no signal present. The line oscillator sounds way off frequency. (picture attached)
  • No channel storing. (SIERRA - 66KS3700 information)
  • Procedure to obtain a better sync.
  • No vertical synchronisation.
  • Insufficient brightness even if adjusting to maximum with RC.
  • The TV does not switch on but fluctuates. (with circuit diagram extract)
  • Set intermittently goes off or into standby when lightly tapped anywhere.
  • When tuned in goes slightly off tune.
  • During switch on the display does not work.
  • When tapped goes into standby. (+ extract of circuit diagram)
  • Mains switch and speech/music switch.
  • Distorted TXT reception (signal OK). TXT module used consists of U125 and U127 (thick film).
  • Lines in picture when using Japanese video appliances.
  • Pal/secam transcoder.
  • When changing to certain programmes the picture is not good at the beginning.
  • Set dead, no 140V HT, 12V feed to the power supply is low.
  • No functions. after start-up (intermittently). (extract of circuit diagram attached)
  • No picture, sound is present. Rastergrid lines present when switching off. (+ extract of circuit diagram)
  • Colour varies until black/white when the appliance is warm.
  • Memory loss in appliances with VST system.
  • Tuning drifting with horizontal white bars.
  • No RC functions.
  • When sweep tuning, station lock does not function. (part of circuit diagram displayed) (66KS3700 tips)
  • No picture. Audio OK . (picture attached)
  • No functions. No display.
  • V2000 loss of colour.
  • Print plate 256 divider U18.
  • Dead. (part of circuit diagram displayed)
  • No picture, No sound. Picture is grey. Balance display on the left.
  • Hum when volume off. Hum in low sound passages. (part of circuit diagram displayed)
  • E/W fault. (with circuit diagram extract)
  • No tuning. (picture attached)
  • Defective vertical linearity.
  • Blank raster with bright, blurred flyback lines. (part of circuit diagram displayed)
  • Trapezoid picture.
  • Brightness fault. (+ extract of circuit diagram)
  • Colour varies. (part of circuit diagram displayed) (SIERRA - 66KS3700 information)
  • When transmitting, a "second language" comes through. (extract of circuit diagram attached)
  • E.h.t. leakage at the tube.
  • Sync IC (TDA3571BQ) replaces IC TDA2571AQ.
  • Moire interference on channel S11 with K35 on S channels.
  • Picture is crooked on either side (E/W). (picture attached)
  • Safety test after repair.
  • Constricted raster. (+ extract of circuit diagram)
  • No picture or audio. Blank raster. Everything is OK after warm-up.
  • No reception during switch on.
  • IF information for stereo appliances, combi tuner and two-tuner appliances.
  • No synchronisation on appliances with fitted TXT. (+ extract of circuit diagram)
  • Frame synchronisation or synchronisation defects. (with circuit diagram extract)
  • No display.
  • Processing of "non-standard" signals.
  • If appliance is cold it ticks; if it is warm, it runs ok; if power supply voltage is less than 220V, it ticks. (with circuit diagram extract)
  • After switching on approx 10-15 times the appliance cannot be switched on any more. Only the left volume balance light is still on. No picture and no sound.
  • Sticks in stand-by. Appliance only starts up when plug V23 has been removed. No display.
  • The television gurgles. (extract of circuit diagram attached)
  • Continuously discharges between tripler and earth.

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Additionally to repairtips or service information 66KS3700 is linked to 18 components (IC's and/or transformers) in the Tectra database, through which you can identify electrical compatibilities (crossreferences) in appliances.


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In the repair discussion pinboard for 66KS3700 there are 5 replies to questions asked about 2 different repair problems.
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Last updated: 16. Aug 2008 18:44:26 MET, doccode ISO9002AS168EKA200805C [cachelite] EURASMOP

Responsible for the content: EURAS International GmbH, Eime, Germany. All rights reserved, EURAS database V2.0 (C) 2002-2008. All brand- or productnames are copyrighted by the respective manufacturer of the appliance and are only being used for identification purposes.