3790 / INTERVISION [TV]

• No channel storing. (service info for INTERVISION -3790)
• Set intermittently fails to start up or goes off at random. (INTERVISION - 3790 information)
• Blurry picture. (service info for INTERVISION -3790)
• Failure of TR10.
• Stereo LED permanently on.
• Will not tune below CH28 and drifts slightly with no affect.
• Clock and radio only, no TV.
• Pincushion distortion.
• Blowing field output IC.
• No picture when cold. (3790 tip from INTERVISION)
• No operation (intermittently).
• LED shows 88.
• Teletext message stays on and/or channels change at random.
• Intermittent colour.
• Black horizontal lines across the screen.
• No TXT. Picture remains and is displaced to left.
• No picture. No audio. Raster OK .
• Interference from fluorescent light.
• Destruction of chopper transistor TR62.
• Field collapse. No sound, no LEDs lit.
• TDA1170S field chip is U/S.
• No RCU function, no front control function.
• No sync. Sound muted.
• E/W fault.
• Width problems.
• Only min or max width control.
• No power supply output.
• Non-linear field scan.
• RC control effected by fluorescent light.
• No RC functions after 30 mins.
• Blows line output transistors at switch-on.
• Unsteady frame scan, lines may be present.
• No fastext functions. (3790 tips)
• RCU does not function, remains on channel.
• Intermittently when the appliance is warm the RCU does not function.
• Intermittent channel change. After channel change red LED is lit for a while.
• Field hold critical.
• Blows mains fuse.
• Green flyback lines at bottom of screen.
• Contrast control not fully operative.
• Line tearing varies with level of brightness and contrast.
• No sound (R156 burnt out is open circuit).
• Standby light flashing when switched on, then appliance goes dead.
• Low contrast/weak picture and weak field sync. Colour OK.
• Arcing then blank raster.
• Intermittent remote control function eg. no colour excessive.
• Gain is low.
• After a few hours the line collapses.
• Low h.t.
• Line pairing at top & bottom of screen. (service info for INTERVISION -3790)
• When appliance is warm synchronisation is weak.
• Standby LED stays on.
• Line drift.
• Displays AGC off tune errors for first 30 mins after switch on.
• No picture. Radio sound on all channels.
• Hanover bars and incorrect colour.
• Low brightness.
• Field foldover at top half of scan.
• After approximately 20 minutes line tearing occurs.
• Line drifts off frequency.
• Small picture and screeching, blows VT68.
• Comes on in standby.
• No audio. LED is green.
• No picture at switch on.
• Green flyback lines at the bottom of screen.
• Goes into standby or LED reads incorrect. (3790 tip from INTERVISION)
• Trapezoid picture.
• Wrong channel display.
• Uncontrollable sound high.
• Tuning drifts.
• Insufficient height and width.
• Tuning comes back after being off tune for first 5-10 minutes at switch on.
• No line drive.
• Ticking noise in standby.
• Shading in picture.
• Field roll (off air).
• Teletext drop out on one or two channels.
• No RC. Stuck on channel.
• Insufficient blue.
• Intermittently destroys TR8.
• Frame fold over at top of screen with bright line across middle of screen.
• Teletext black box stays on screen.
• Picture shifted to the left.
• Beam sensing fault.
• Blank screen with no RCU functions.
• No picture. Intermittent LED display.
• Solenoid operates after about 1 minute.
• No functions.
• Dead. Slight ticking noise.
• Contrast problems.
• Squealing noise from chopper Tx.
• Faulty line sync.
• Lines flash on picture, may not affect all channels.
• Volume varies.
• TR66 and mains fuse blown intermittently.
• Goes to standby when channel change selected intermittently.
• Small frame. (service info for INTERVISION -3790)
• Dead. Channel indicator OK.
• IC101 (SAA5012) repeatedly fails on PC1515.
• Poor sync when warm.
• Sound blasts out. Colour and brightness varies.
• Frame rolling.
• Patterning on all channels.
• Tuning drift. Does not tune low frequency channels.
• Very intermittent failure to start up (works normally for days or even weeks).
• F51 blown intermittently.
• Reduction of field scan to 2-3 inches.
• No picture and severe hum.
• Red looks fluorescent, other colours appear weak.
• No synchronisation.
• Low line frequency.
• Intermittent strat-up, then trips with ticking noise. (INTERVISION - 3790 information)
• Intermittent field sync.
• Intermittently goes into standby or TXT.
• Pattern on TXT.
• Will not start.
• Low numbered channels cannot be stored.
• Poor picture focus.
• No colour.
• No sound, no channel change.
• Black smearing on peak whites.
• Line collapse after a few hours.
• Intermittent black fuse.
• Dead. High pitch whistle.
• Sound mute LED on. No channel display or RC function.
• Poor function.
• Poor or no RCU operation at close range.
• Focus out.
• Line collapse intermittently.
• Incorrect line speed. Intermittently OK when switched to AV channel and back again.
• Enter service mode.
• Incorrect LED eg. 11 for 1 or 22 for 2.
• No RCU functions. Manual functions OK. (3790 tip from INTERVISION)
• Thin lines across screen.
• Blank raster, standby LED on display shows 8, 88 or 888.
• Colour fault on teletext. (service info for INTERVISION -3790)
• Picture is missing, just a green raster with flyback lines. (3790 tips)
• Vertical collapse.
• Flyback lines at bottom of screen, increasing in size over bottom third. Lines are always green.
• Contrast control not working.
• Picture is very noisy.
• Insufficient purity. (service info for INTERVISION -3790)
• Intermittently dead then permanently dead.
• Black fuse. (service info for INTERVISION -3790)
• Flyback lines at top 1in.
• No TXT (intermittently).
• No scan.
• Appliance is dead, HT voltage at approximately half. Channel indicator ok.
• All HTs high from chopper transformer.
• Blows TR10 at switch-on.
• No sync on TXT.
• No manual functions. RCU functions OK.
• AGC overload CH2 only.
• Blows fuse. Screeching noise from LOPT prior to blowing fuse. (3790 tips)
• 115V HT rail reads high.
• Dark picture. No sound. Stuck in mute. No RC functions.
• Appliance hums (mechanically).
• Intermittent start up then tripping with ticking.
• Line sync drift on TXT only.
• Mute LED on.
• Reduced horizontal size.
• Goes into standby every 10 mins.
• No remote stuck on channel 8/6.
• At switch on crowbar fires and blows fuse. (INTERVISION - 3790 information)
• Line lock lost at switch on and when changing channels. No signals. (3790 tip from INTERVISION)
• Low audio.
• The appliance blows line output transistor at switch on.
• Colour is missing or not correct.
• After 30 mins, set goes into standby. Relay chattering.
• CRT problems.
• The appliance goes into standby intermittent if channel change is selected.
• Picture and sound are missing, raster ok.
• Defective line linearity.
• No picture.
• Line lock is lost on all but video channel.
• Intermittent graphics on display.
• Buzz on sound but only in the standby position.
• Line collapses intermittently.
• No RCU functions.
• HT supply is high.
• No vision or sound. Incorrect LED display, no RCU functions.
• No standby if switched off/on from mains socket.
• Teletext problems.
• EHT is excessive, IC55 (TDEA1170S) is damaged.
• Picture narrowing from the sides.
• Negative picture.
• Mains voltage hum: defective scanning, dirty. Birgit?? Lynn, I don't really know what is dirty. Could it be the degauss coil?
• Humming on standby. Radio scale light remains on.
• Intermittent poor grey scale then video goes off.
• Appliance does not function; 115V is too low and fuse FS1 blows after a short time.
• Field linearity problems. (3790 tips)
• No AV on channel 8 and 9. OK AV on channel 1-7.
• Blowing mains fuse start up IC57 and chopper transistor TR62.
• Vertical fault.
• Height problems.
• No function of RC during standby. Stays on channel 1.
• Offset picture to the right. (part of circuit diagram displayed)
• Loss of picture after 10 mins.
• Lines flash on picture, may only affect some channels. (3790 INTERVISION repair tip)
• Dead.
• Intermittent RCU functions.
• No TXT.
• Corrupted TXT. Displaced to left hand side. (INTERVISION - 3790 information)
• No RC functions (intermittently).
• Reduced picture with screeching noise. (3790 INTERVISION repair tip)
• Appliance remains on programme 8.
• Poor field sync with computers.
• Line hold out of phase lock.
• No picture or picture flashing.
• Field jitter. Intermittent colour. No TXT. (3790 tips)
• Blank screen in TXT mode and only black graphics in mix mode.
• Bent verticals.
• Amplification is too weak. (INTERVISION - 3790 information)
• Solenoid operates approx about 1 min.
• 115V rail high (137V) bent verticals/ whistle.
• Picture shifted to left hand side by about 1/3.
• No line sync.
• Pincushion distortion with brightness fault.
• Picture disappears intermittently.
• Black lines across top 1/3 spreading as set warms.
• No mute, standby or volume +/-. Channel change OK.
• No channel indication. No tuning.
• Appliance is slow to come on, about 10 seconds.
• No manual or remote channel change, mute light on.
• RCU does not control volume, contrast, colour or brightness.
• No standby picture control.
• Line linearity problems.
• Blank raster, sound OK.
• Zig Zag verticals.
• Line tearing after 20 mins.
• Distorted field scan.
• Line twitching.
• RCU transmitter problems.
• Bent verticals and whistle.
• Will not come on if switched back on while still warm.
• Green looking faces.
• No TV or radio. Clock OK.
• Appliance and LED fades at switch on.
• 115V rail takes anything up to 5 mins. to occur.
• No picture or intermittent picture when hot.
• Appliance is slow to start up and the picture pulses.
• No TXT. Page number only.
• Radio and TV do not work.
• No standby via RC. LED OK.
• Set won't start up.
• Intermittently dead. When OK intermittent sound mute and channel change.
• Distorted sound right channel (mono or SS).
• Cramped frame.
• Trips.
• Screeching noise from PSU. Ripple effect on screen.
• Intermittent line collapse then fades off.
• When appliance is switched on the mains fuse blows.
• Distorted audio.
• No remote functions step up/down button only. (INTERVISION - 3790 information)
• Picture is small.
• No field sync. Picture rolls.
• Voltages from chopper transformer are too high.
• Teletext message stays on screen.
• In standby when switched on or audio at maximum.
• High pitched whistle from left hand loud speaker.
• Stations can be searched for and found but not memorised.
• Drop out on TXT. (INTERVISION - 3790 information)
• Ballooning effect.
• Reduced vertical and horizontal size.
• Picture collapses.
• Picture blanked out on TXT.
• Grainy picture.
• No functions. Very dark.
• Width is reduced and East-West correction is poor.
• Intermittently blows chopper transistors.
• Picture disturbance with change of picture content. (INTERVISION - 3790 information)
• Very bad line pairing top and bottom.
• Striations down left hand side.
• No sound or raster (low frequency popping noise).
• No switching to standby with RC (LED lit).
• No frame sync.
• Weak contrast.
• Stiations.
• Humming.
• Sound blares/brightness and colour varies. (INTERVISION - 3790 information)
• No picture. Sound OK.
• The appliance has a dark picture.
• Comes up slowly with picture pulsating.
• HT and LT low. (3790 INTERVISION repair tip)
• Picture flutters when various brightness and contrast levels selected.
• The appliance does not turn on from standby and then sticks on channel 1.
• Tuning fault (channel 1 memory has disappeared).
• Hum from set.
• Field linearity is poor.
• No sound or picture, channel indicator lit, high tension is normal value.
• Occasionally appliance does not function.
• PSU only starts intermittently. Sometimes it starts once a day but not in successive occasions.
• Blowing BU508 at switch-on.
• No remote function after 30 minutes.
• Screeching noise from LOPT and D28 (BY299) S/C.
• Poor line sync.
• Fuse blowing L65 hot 115V high.
• No audio.
• Low HT when warm. (INTERVISION - 3790 information)
• Very faint sound.
• Dead. LEDs lit.
• Intermittent cuts out of all voltages except 12V.
• No AV CH8.
• 1.6A mains fuse blowing.
• Field cramping.
• The line control transistor T9062V TR67 has a short circuit and mutilates the safety resistor R222 (collector circuit).
• No RC functions except for step up and down buttons.
• Striation effect.
• Set will not start.
• Blank raster.
• IC101 (SAA5012) repeatedly faulty.
• Frame bounce when cold.
• No RCU and no functions without remote lead removed.
• No sync, RCU function or sound.
• No or weak signal.
• Bright picture with flyback lines.
• Intermittent HT (135V).
• Occasionally RCU function has no colour or too much colour.
• Ripple on picture with reduced width. Clears after a while.
• No picture blank out on teletext.
• Does not switch to standby. (INTERVISION - 3790 information)
• No red or red band at top of picture.
• No E-W correction.
• Noise bars.
• Excessive readings on all HT supplies from chopper transformer. (3790 tip from INTERVISION)
• Over volts surge at switch on.
• Horizontal black lines on screen.
• Black lines at top 1/3 increasing as set warms up.
• Battery dead.
• Line frequency incorrect.
• Low contrast.
• Picture shifted to right with a black band down left hand side.
• Sound on vision effect.
• Appliance does not function. Mains fuse blows.
• Line output and driver transistors blown up.
• Goes to standby a few times.
• Picture is grainy and sound noisy.
• Low gain. (3790 tips)
• Intermittent picture and sound; similar to tuner fault.
• Intermittent loss of sound and raster. (service info for INTERVISION -3790)
• Picture is missing, raster and sound correct.
• Intermittent fault ,no manual or remote channel change and only the mute light on.
• Intermittently dead. Slight tripping and video fault.
• No functions, power supply is working.
• No RC functions.
• Appliance intermittently pulses off then on again, after running it for several hours the fault becomes more frequent.
• Set will not come out of standby.
• Very weak vision with little or no sync.
• Intermittent on/standby. Remains on Ch8 with mute LED on.
• Colour on teletext is missing.
• Tuning fault (audio mute and channel change with the previous/following key fails).
• Line pulling during warm up.
• Tuning fault (IC901 loses the memory after 1 week).
• The sound is ok, no conductor.
• Vertical jitter.
• Line faults.
• No function.
• Frame foldover or creeping. (3790 INTERVISION repair tip)
• IC57 and TR62 blown.
• IC601 (TDA3560) becomes defective after a short time.
• Remote control does not work from standby, stays on channel one.
• Vertical foldover.
• Intermittent crackle on left hand channel and plop when sound is muted. (3790 tip from INTERVISION)
• Incorrect line speed. AV channels OK on prerecorded tapes.
• No picture just lines.
• Field jitter with black lines across picture.
• Shuts down after a few mins.
• Lines flash on picture, may be affect all channels.
• Intermittent roll when hot.
• When pressing buttons 1 to 5 the channels activated are 5 to 8. (INTERVISION - 3790 information)
• Field foldover at top with reduced width.
• Buzz in audio.
• Line synchronisation is missing.
• Changes channels at random and goes into standby.
• RC works when a few feet away only.
• Contrast control is open circuit (burnt).
• Slow to come on.
• Will not come out of standby. (PC1044)
• No standby from remote (LED lights).
• Poor sync lock when warm (approx 10 mins after switch on). If channel changed, line sync sometimes pulls in ok but at other times, slips through with field sync.
• Stuck in standby.
• Lines flashing on picture, may not affect all channels.
• Poor field sync with computers. (3790 tip from INTERVISION)
• Blank raster, no sound preceded by arcing.
• Width control gives only maximum or minimum width.
• Radio and TV are dead.
• Goes into standby or intermittently changes channel.
• Contrast control O/C.
• Line synchronisation is weak and does not lock when cold. (INTERVISION - 3790 information)
• No RC functions. Manual OK if RC lead disconnected.
• Height drifts.
• No start-up. after warm-up.
• Various hum bars or distorted picture.
• Sound is excessive and cannot be controlled. Remote volume changes the brightness.
• No output from IC1807.
• (Pg 1 of 2) Dead.
• Stuck on programme 8. (service info for INTERVISION -3790)
• Smearing on peak whites.
• Picture unstable with patterning.
• When replacing frame output IC, TDA 3652, no longer available.
• Field collapse. No sound or brightness.
• Grey scale fault (TDA3560) CRT trouble.
• No picture, no sound. Standby LED on.
• Picture interference plus noise on sound.
• When sound mute LED is on, no channel display/RCU functions.
• Contrast control does not function correctly.
• Brightness fault.
• Appliance switches off and back on. Fault diminuates after a few hours.
• Vertical roll.
• Smearing in picture.
• No width or pin cushion control.
• Flyback lines.
• Starts in standby and squeals.
• No picture, no Eht no heaters all Ht's slightly low.
• Focus problems.
• Appliance is dead, just low ticking.
• Rolling with dark scenes.
• Incorrect picture size.
• No LED display.
• Ghosting effect.
• Terrible field linearity.
• Relay chatters.
• No vertical deflection.
• Synchronisation faults.
• Only lower half of text correct.
• Line twitch.
• Poor picture, lack of contrast. (3790 INTERVISION repair tip)
• Low gain.
• No picture or sound. Channel indicators OK.
• Moire pattern.
• No picture, no sound. Low frequency popping noise.
• Stuck in standby. Receiver ticking. (INTERVISION - 3790 information)
• Dark picture.
• Line frequency drifting.
• No line sync at switch on.
• Sound OK but no line.
• At switch on line synchronisation is missing. (with circuit diagram extract)
• Vertical collapse (intermittently).
• Excessively bright raster.
• Line frequency appears on part of screen, when cold. (service info for INTERVISION -3790)
• Field collapse, no sound and reduced width.
• Reduced vertical size.
• Relay clicking over. No LED or EHT.
• No tuning.
• Destroys TR8.
• No sound and mute light glowing slightly.
• Picture blacks out to white raster.
• No line/field sync, no sound (muted) and no TXT.
• Picture offset to the right hand side.
• Interruptions. (3790 tip from INTERVISION)
• Snow or ghosting.
• Width defects.
• No field sync and no sound.
• Intermittently goes into standby, volume variations and scrambled teletext. (INTERVISION - 3790 information)
• Intermittent low gain.
• Picture pulsating and changing colours.
• Tuning drifts, patterning.
• Blows fuse. Line output transformer is noisy then fuse blows again.
• No or weak colour.
• Blows TR66 and mains fuse intermittently.
• Line output transistor TR68 blown.
• Ringing on verticals.
• No RCU. No tuning.
• Sound on vision.
• No TXT on some channels. (3790 tips)
• Difficult line lock from cold. Line pulls.
• No manual channel change. OK on RCU.
• Picture is missing, sound ok.
• Brightness pulsating.
• One colour poor, others ok. (INTERVISION - 3790 information)
• Intermittently dead.
• Intermittently 119V rail varies.
• Noise bars across picture.
• Trips. Hum from speaker. (INTERVISION - 3790 information)
• Line appears to break-up with bright blue picture.
• When replacing frame output IC. (TDA3652 is no longer available.
• Excessive EHT damaged IC55 (TDA1170S).
• No picture or sound. LEDs lit.
• General frame or field defects.
• Picture flutters at certain brightness and control levels.
• Picture breaks up with change of picture content.
• Snow in picture. No channel display.
• After heating up, the timer lock is very weak. If you change channels, the line synchronisation is occasionally correct but it goes wrong in relation to the frame synchronisation.
• Stuck in standby via RC. Locked on CH1.
• Frame collapses, total collapse at bottom and half scan at top,can be intermittent.
• Black lines at top of screen, increasing when warm.