Page 1
USEFUL INFO.
Adjustment of the servo processor.
Fault 1 The servo processor is adjusted by short circuiting test point BT08 to ground: BT00 (2 adjacent test
points next to the processor). Then playback a test cassette. By doing that the head switching pulse is calibrated
automatically. (Test tape MA2).
Part number info: RC
With VR4A10 appliances a RC type FS4A10 is used.
With A935 appliances a RC type FB890 is used.
Desc. Part no.
RC FS4A10 4900 059 335
RC FB890 349 398 124
Service info: Pin occupation of scart socket.
Pin Signal Pin Signal
01 Audio R Out 12 NC
02 Audio R In 13 Red earth
03 Audio L Out 14 NC
04 Audio earth 15 Red In
05 Blau earth 16 Blanking
06 Audio L In 17 Video earth
07 Blue In 18 Blanking earth
08 12Volt AV 19 Video Out
09 Green earth 20 Video In
10 NC 21 Earth plug
11 Green In
SERVO
No picture or sound. Capstan and drum run too fast. The right reel table pulls with full force (12V operation
voltage).
Fault 1: Check if 9.7V in the power supply is correct. If not, TP73 (BC368) in the power supply is defective.
Voltage drop over E/C path is too high. Important: only use original type BC368
The drum motor does not turn.
Fault 1 IC2 (servo board) is defective.
The drum motor turns in the wrong direction.
Fault 1: IC2 (VC2023A) drum servo is defective. Pin 34=3,14V.
Head drum going backwards
Fault 1: IC2 (VC2023A) drum servo is defective. PIN34 =5.14V.
No reel or capstan motor.
Fault 1 M50965-612SP. Components: IC601 on mechacon board.
Drum unlocked.
Fault 1 VC2023A. Components: IC2 on servo.
No reel.
Fault 1 IM 54644BL - Mechacon. Components: IC603.
No capstan.
Fault 1 M54644BL Mechacon. Components: IC604.
Slow speed, noise bar runs through the picture, capstan servo.
Page 2
Fault 1: Change or check C25 and C26 (electrolytic 4.7MF).
On/off LED does not light up and the head does not turn.
Fault 1: Replace the power pack. Fit STK5481 with a cooling paste.
Motor runs at switch on then shuts down.
Fault 1: Check the mode switch is making contact.
Runs too quickly. VC2023A ok. Runs normally in PB in the middle of the cassette.
Fault 1: Check 12V motor with the oscilloscope. Otherwise check C10 and C2. If no sound suspect the capstan
motor.
Fault 2: Check the condition of the tape tension. If ok, suspect the system microprocessor IC601.
Incorrect capstan and/or reel motor speeds.
Fault 1: Replace IC601, IC602, IC603 and IC604. Then physically check the reel and capstan motors.
Fault 2: Check pin 8 of IC601, (IC603 is reel motor control and IC604 capstan motor control).
Tracking problems.
Fault 1: Check conditions on IC101 and LPF702; check individual channels. Then check IC2 (VC2023A). If
symptom is intermittent, check this IC for dry joints.
Fault 2: Check correct aerial setup.
Fault 3: Check FM envelope alignment is correct.
Intermittent drum servo problems.
Fault 1: Replace M54519P and readjust R10 and R207.
Capstan motor does not run. If PB pressed, tape is laced up and pinch roller presses tape against capstan shaft.
Fault 1: Capstan motor is defective and has damaged IC604. Motor and IC should both be replaced at the same
time because otherwise the IC fails again.
Ref. Desc. Part no.
- Capstan motor 339304601
IC604 IC 339576066
Capstan motor runs in PB. Head drum runs.
Fault 1: D.C. voltage at pin 52 and 53 of IC601 on mechacon board should alter if capstan motor starts up. If no
alteration takes place, check if 5V square-wave signal (25Hz) of drum flip flop arrives at pin 34. The output pin
11 of IC2 on servo board supplies this signal to inform mechanical control processor if this head drum is
running. If this signal is absent, capstan motor is not controlled. If this is the case, replace IC2.
AUDIO
AUDIO
AUDIOAUDIO
During own recording the old sound is not erased.
Fault 1: The capacitor CF06 (0,1µF) on the video signal board next to the erase oscillator coil is defective
(bottom right hand side).
Fault 2: Fit a 5.6nF capacitor in parallel with C23 and R22 (base of Q1) on the signal board (audio section).
Fault 3: [Plenty of bias at T1 but does not reach erase head]. Check IC5 (uPA81C) on mechacon PCB.
Occasionally audio track is not erased.
Fault 1: On audio board 09 solder a 5.6nF (5%) capacitor parallel to C22.
Wow on audio.
Change pinch roller.
Poor picture, very little speed. No sound as if the heads were dirty.
Fault 1: Check the head amplifier board, the flip flop, 5V and check the earthing screws.
Problems when changing channels, tuning fails and goes back to the original program.
Fault 1: Check all uncoupling caps on the power supply board for dry joints.
Page 3
The previous sound is not erased with own recordings.
Fault 1: Capacitor CF06 (0.1UF) on the video signal board (lower right) beside the erase-oscillator coil is
defective.
Old sound is not erased when re-recording.
Fault 1: Fit a capacitor (8.2nF) parallel to C23 and R22 (base of Q1) on signal print in audio unit.
During PLAY sound is intermittent.
Fault 1: Check C5 for dry joint.
Sound is poor.
Fault 1: A/C head is defective.
Intermittent sound erase.
Fault 1: Fit a .0056 (5600pF) across C22 in parallel; part number QFN31HJ562.
Fails to erase sound.
Fault 1: The erase head plug/socket is intermittent; cut off and rewire directly.
Sound buzzes in E-E; pre-recorded tapes OK.
Fault 1: Check filter CF1 (6MHz).
E-E audio low and distorted.
Fault 1: Check C15 (2.2uF/50V) on small audio PCB.
High pitched whistle and venetian blind effect on E-E picture and PB of own recordings. Pre-recorded tapes OK.
Fault 1: Check C5 (47uF) in power supply.
PICTURE
PICTURE
PICTUREPICTURE
During playback unsynchronised stripes can be seen.
Fault 1 The head drum speed is too high. The picture is recognisable when applying external braking. ICF 2
(VC2023A) on the servo unit is defective.
No EE picture, the tuner unit is defective.
Fault 1 IC IT20 (TD6316) on the signal board (tuner section) is defective.
During play the picture sways.
Fault 1 The lower drum is defective.
No picture during PB.
Fault 1 The test picture generator cannot be adjusted. Resistor R1 in the RF convertor is open circuit.
Fault 2 No test picture. JC JN40 (TAD 3740) on the video board is defective.
No EE and tuner picture.
Fault 1 Dry joints on plug points JO16 and JO20 (signal board).
Sometimes no own recording possible, only noise.
Fault 1 Pot PN51 (1KR) on the video signal board (right base board) next to JC TD3740 is defective. Exciting
current does not get to the head amplifier.
EE picture is squeezed and folds to the side. Also colours are washed out and faded.
Fault 1: IC102 (7VT2DE = emphasis/ equaliser) on the video-luminance board is defective. Sensitive to cold.
No FM envelope on playback (no record envelope present).
Fault 1 Replace IC1 - HA11870NT. Components: IC1 on Pre/Rec Amp board.
No channel display, blank raster.
Page 4
Fault 1: Replace M50440-3915P on the tuning print.
No E/E picture, colour or sound.
Fault 1: ICJW13 (TDA375) on the signal board (bottom right) is defective.
In playback regular band of interference running from the top to the bottom of the screen.
Fault 1: Check the 12V and 45V filtering.
Blank raster on play and E to E.
Lead broken on print at junction of C3 on terminal panel.
Poor picture, very little speed. No sound as if the heads were dirty.
Fault 1: Check the head amplifier board, the flip flop, 5V and check the earthing screws.
Noisy picture, stripes. One head is missing.
Fault 1: In the head amplifier-IC HA, the internal switch over is defective. One head is always grounded,
therefore only one FM signal.
EE picture and picture in Play are dark via AV mode. Only snow via HF mode.
Fault 1: CP3 on the power supply board is defective.
Fluttering picture.
Fault 1: IC2 (VC2023A) on servo PCB is defective.
Lines in the picture. One head is missing.
Fault 1: Internal switching in head amplifier IC HA is defective. One head is always grounded therefore only FM
signal.
Dark EE picture and picture in PB via AV function. Snow in HF function.
Fault 1: CP3 in PSU supply is defective.
No test picture, no playback.
Fault 1: CP2 on the power supply board is defective.
Poor-quality playback picture has lots of very small herringbone squiggles all over it and a grainy look with
black tadpole-like spots trailing across on peak whites.
Fault 1: This can be caused by IC601 (M50965-612SP) syscon microcomputer chip.
Snow bars running through the picture in Play.
Fault 1: Defective capstan servo. C25 and C26 (4.7µF) on Pin 40 of the IC2 on the servo board are defective.
While the sound is recorded, the previous video is erased and even the new video information is lost.
Fault 1: When removing the complete erase head, the previous video remains. A test on the prerecorded tape
shows that the /REC line does not go at low level. The cause is a dry joint on the comb connection (CN2)
between the mechanical control board and the video board.
Picture rolls or shudders.
Fault 1: Check conditions on IC101. If ok, check for defect after its outputs. Alternatively check FM waveform.
Playback picture is poor or intermittent.
Fault 1: Check pin 13 of IC101 for dry joints; if ok, trace along this path for o/c.
E-E problems.
Fault 1: Check circuit protector CP3 for o/c plus circuit to this protector.
Fault 2: [Crushed E-E picture]. Check IC102 (7VT2).
Fault 3: [Incorrect 5V supply]. Check C3 (2200uF) by replacement.
E-E picture missing, sound ok.
Fault 1: Check C243 (220uF) connected to pin 8 of IC201 (HA11738) for open circuit.
Page 5
Noise bars every 6 secs during PB of recordings. PB of prerecorded cassettes ok.
Fault 1: Check on servo board CN1 pin 1: 8Vpp. If low, check adjustment of LF head. If the same, check IC2 pin
2: 6Vpp. If low, check sync on pin 10. If ok, suspect IC2.
COLOUR
COLOUR
COLOURCOLOUR
Intermittent loss of colour on playback
Fault 1 Check IC203 (HT4239) or check L215.
No colour on playback or record, all other functions ok.
Fault 1 Change IC101. Component location: On main PCB. Circuit diagram ref: IC101. Explanation: In this
case sync seperator output on pin 2 was of insufficient amplitude about \volt, it should be about 5V peak to peak.
This line and frame sync is used in the colour processing system. AFC burst gate, AFC detector, 4 phase shaft, {
countdown.
No colour during own recording
Fault 1 Signal break between LC16 and LN98. There is converged colour on 26/ JC20 but no longer on JN98.
Sometimes the colour is missing during EE.
Fault 1 Capacitor CC03=10µF on pin 2 of IC20 (chroma board) is defective (IC20= TDA3/60).
No colour and sound during PB.
Fault 1 Pot. 06 next to IC JW13 on the Y-board (base board). Adjust 9KHz on pin 8 of IC JW13 during EE
mode and test generator 629.
No colour with special functions (pause, picture search).
Fault 1 Measure Pin 15 of IC01 (TA8644N) on the video-signal board. With the special functions the value
shouldn't drop below 3.5V. Check CC21 (1UF) for a short circuit and loss of capacity and also check diode
DC21 for a short circuit.
The cassettes go to black and white in playback, the sound is ok.
Fault 1: Replace the R327 by 18kohm.
Fault 2: Check C332 on 2/IC301.
Colour is missing.
Fault 1: Check IC101 on Y/C panel.
No colour playback on known good recordings and no drum lock or chroma with own recordings.
Fault 1: Check C347 connected to IC402 for dry joint.
FUNCTION
FUNCTION
FUNCTIONFUNCTION
No programme change possible.
Fault 1: Switch stays at 0. Storage IC3 (M58655P) on the HF board is defective.
The appliance does not switch on or does not take any function.
Fault 1 IC1 (STK5481) on the board 02 in the power supply is defective.
Performs several functions at once. At switch on all motors run, "cassette in appliance" LED lights and no
further functions possible.
Fault 1: Breaks at plug connections on the main board.
During forward channel select the desired channel is skipped (appliance moves onto the next one). Tuner does
not function.
Fault 1 Video section and the recorder are ok. Break in the data line between tuner and the timer plug panel
CN11 on the mother board.
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Only upward channel switching is possible.
Fault 1 : Station search does not work. IC2 (M50440-394SP) on the tuner IF board is defective.
"Cass." and time is shown in the display but no further function.
Fault 1 The timer IC (IK60RCS408C) is defective.
Display is dark, no function, power supply unit oscillates.
Fault 1 Check pin 51+52 of ICI60 in the operation unit for oscillation. If oscillator does not oscillate, briefly set
a 5V "H" level on pin 49. If all functions again appear, the reset pulse has not been set correctly. Remove the
dry joint on CK47.
All functions are dead.
Fault 1 Check for a fault in the following: CP4 (open circuit) and 12V regulator or the motor drive IC602.
No LED indication, no drum rotation in any mode and appliance shuts-down after a few seconds in FF/rewind
modes.
Note: In the fault condition the switched 5V rails are missing.
Fault 1 Check the circuit protector CP3 and the power supply IC (5TK5481).
The recorder does not record.
Fault 1: Cable break (video mechacon board).
Fault 2: Check ribbon cable link CN2 for dry joint.
When operating the forward and rewind button the drive switches to PB, the head drum does not turn.
Fault 1 The tape load sensor is open circuit.
Channel adjustment is ok, no station indication, PDC is shown continuously.
Fault 1: 5V power supply is missing on IC20 in the tuner unit. The wire bridges JO16 and JO20 (below the
tuner) are loose (connecting the right angled direction boards).
No EE, PB or test picture.
Fault 1 IC fuse CP2 in the control unit is defective.
After a few sec. the appliance switches from PB to stop.
Fault 1 The supply FG sensor (supply sensor) is defective.
Note: Switches to 1,2V but should be 0V.
The operate LED does not light and the head does not turn.
Fault 1 Replace the power pack. STK5481 must be sprayed with cooling spray.
Clock display ok, loads cassette but no transport E-E.
Fault 1 Check CP3 open circuit (reg PCB).
Intermittently playing fast. When pause is selected during play the tape does not stop but moves forward very
slowly.
Cause: High take-up drive, even in the pause mode when there should not be any.
Fault 1 Voltage at pin 4 of IC601 does not rise sufficiently high to switch Q604/5 off. The voltage across C608
is always high, therefore around 10.5V even in the stop mode. The mechacon chip IC601 is at fault, with an
internal leak to chassis from pin 4.
Intermittent damaging of tapes. Also intermittent recording or playback.
Fault 1 Check for dry joints around transistor Q603.
No E-E (no 5V).
Fault 1: Check CP3 open circuit
No play no capstan motor.
Fault 1 Check IC601 mechacon.
No E-E on play back.
Page 7
Fault 1 Q113 open circuit.
On eject cassette motor would still keep turning after cassette has been ejected. Machine software will then shut
motor down after a period of about 10 seconds.
Fault 1 Change the carriage. Component location: On main deck. Explanation: The carriage position photo
interuptor malfunctioning.
Faulty power up. Does not switch from long play to standard play.
Fault 1 CN26 and C28 plugs where reverse also dry joint on CN2 connected to mechacon board.
Channel change problems: intermittent tuning, returns to original program.
Fault 1 Check all decoupling caps on power supply panel for dry joints.
The appliance switches on but no operations light.
Fault 1 Replace regulator IC (STK5481).
Tape runs fast for the first 10-15 mins at the beginning of a cassette/tape, does not stop in pause.
Fault 1 Replace mechacon CPU and add 1KR resistor from pin 4 IC601 to the anode D612 to protect the IC
port.
Intermittent: stops after 1-2hrs use, counter works only in rewind/fast forward.
Fault 1 Clean or replace both reel sensors.
Appliance only functions for a few seconds in play-back, FF and REW. and then it switches off. In playback it
switches off in laced up condition.
Fault 1 If the clock fails as well, the control panel processor could be defective or has a loose connection. If
everything else is ok, replace the mode switch anyway. Does the counter mechanism run ? If not then keep
looking.
The playback head does not turn during play command.
Fault 1: Check IC2 (VC2023).
The appliance indicates the presence of a cassette when none has been inserted. When a cassette is inserted the
appliance will not go to play.
Fault 1: Check for open circuits on the connectors of the chassis.
All functions are correct except when inserting a cassette the playback head does not turn after pressing play.
Fault 1: Check the position and the contact position.
On PB the set switches back and forth between SP and LP at the beginning of the tape.
Fault 1 Check the connections to the ground and the reel motor for stiffness. Check the slide coder which may
be dirty and clean the synchro head.
When recording from the TV onto a played tape the sound is not erased. The sound of the new recording is not
recorded.
Fault 1: Interference in the erase oscillator.
In playback unlaces again immediately (head does not turn). With FF and REW appliance switches off after 3 to
4 secs. Counter does not run with any function. Clock is ok.
Fault 1: Replace reel sensor and mode switch.
Fault 2: Check STK PSU-IC and earth screws.
Tape runs too fast at start of cassette for approx. 10 to 15 mins. Does not stop at PAUSE command.
Fault 1: Replace mechacon CPU and add resistor (1K) between pin 4 of IC601 to anode D612 in order to protect
IC input.
Drum motor does not run. LEDs of function keys are not lit, functions OK.
Fault 1: Fuse FC3 on PSU is defective.
Display OK. No function.
Page 8
Fault 1: Check IC1 (STK5481) on board 02. Check TIME IC (IK60...). Check CP4 (o/c) and regulation 129 as
well as IC602.
Erratic audio erase and record.
Fault 1: To cure add a mylar capacitor between pin 2 of oscillator transformer and base of oscillator transistor value 5.6nF for models up to 3V57, 8.2nF in the case of 3V58 and later models.
Display shows flashing REC and tape indication. All other functions possible. Display continues to flash when in
standby.
Fault 1: Loose connection of flat cable between servo and mechacon print.
No display and no record.
Fault 1: If mains interruption can be ok when unplugged and switched on again the microcomputer will reset.
If the fault with one of these appliances is permanent or intermittent, failure of some of the front-panel keys
(station selection etc) to operate.
Fault 1: Check for dry joints at CN1 where it is soldered to timer PCB. No 15 before getting involved with the
front panel.
Time remaining function does not work - just dashes in display when appliance put into play and the function
selected.
Fault 1: Take up sensor ok. Check supply sensor input to the syscon chip IC601 (pin 35). No high/low cyclic
change, just a steady high level. Make a check with the bottom cover removed, at the sensor's output connection.
High/low switching output here and within a few secs a time remaining display. Cause of fault is a loose earthing
screw - the one that earths the optocoupler's LED and opto-transistor emitter connections. The pressure applied
when connecting a meter to its output was enough to re-establish the earth connection.
Poor sensitivity on all bands.
Fault 1:Q1,2sc 3354.
Appliance does not fully load, drum does not turn and PLAY does not function.
Fault 1: Check the tension spring, item 75, is connected at both ends.
PLAY does not function.
Fault 1: Capstan motor is defective.
Intermittently appliance play quickly and PAUSE does not function, take-up drive is high.
Fault 1: Check mechacon IC601.
Channel change buttons are defective or intermittent.
Fault 1: Check CN1 for dry joints.
Difficulties in channel change and memory.
Fault 1: Check C7 for dry joint.
After a few seconds appliance cuts out, mode motor runs.
Fault 1: Check mode motor drive belt.
Displays time but does not start up. On/Off command does not function.
Fault 1: [STK has been changed. 6V on pin 5 of STK. The unswitched voltages are ok, the switched voltages are
missing. All the fuses are ok]. Check IC601 pin 6:ON OV, OFF 5V. Otherwise check pin 1:5V, pin
29&30:oscillator, pin 28:RESET low state.
During PLAY appliance switches to REC.
Fault 1: Check supply photosensor for dry joints.
Cannot change channels.
Fault 1: Check IC2 (M50440-391SP) in tuner circuit. If ok, trace channel circuit on IC601.
Intermittently cannot change channels.
Page 9
Fault 1: Check C7 on power supply board for dry joint and check 30V line. If 30V reg supply is missing, check
the tuner BT for shorting to the bottom cover; check print for break from IC3 to 5V regulator chip.
FF and PAUSE do not function correctly.
Fault 1: Check IC601; if ok, trace incorrect function path.
Appliance loads but no functions possible.
Fault 1: Check circuitry to CP3 or replace CP3 if necessary.
Only FF regardless of which function key is pressed.
Fault 1: Check right hand reel sensor.
No function. Cassette accepted. "-" appears beside channel no. in display.
Fault 1: Child safety is active. Appliance is unlocked if switched on with RC.
No function. Switches on by itself as soon as it is plugged in. Left reel table runs then appliance switches off. No
cassettes accepted.
Fault 1: Poor ground connections on drive board, where capstan- and reel-motor, wiper switch and reel sensor
are positioned. Fixing screws of connection board do not make a good contact. Place star washers below both
ground screws.
No function. Cassette is accepted.
Fault 1: If STOP lights up in clock display, appliance is blocked with child safety lock. To unlock switch on with
RC.
TAPEDRIVE
TAPEDRIVE
TAPEDRIVETAPEDRIVE
No cassette accepted.
Fault 1: Plug BW05 on upper video board is intermittent on pin 9.
Fault 2: [Drum does not turn]. STK5481 is defective. Remove switched 5V and 12V lines; if no results, check
these lines tracing back from incorrect reading.
Intermittently ejects the tape. Rewinds or ejects the tape during record.
Fault 1 Go to the PCB directly under the take-up spool and check that the earth screw is tight.
Loads faulty no play no drum rotation load incomplete.
Item 75 tension spring disconnected one end.
Poor search.
Fault 1 Change idler. Tape deck.
Intermittent (reel motor) tape loop on unload/FF or rewind/play/record.
Fault 1 Reel motor.
Switches off when tape unwinds.
Fault 1: In the drive, the quick sensor on the relay board is defective.
Cassette eject is blocked.
Fault 1: The left main toothed wheel is jammed.
Note: To correctly install the main toothed wheel the cassette compartment should be out. Also replace safety
rings 71 and 72.
Eject function works but cuts out.
Fault 1: Check the board below the take up reel table. Tighten the earthing screw.
No tape drive (capstan).
Fault 1: IC604 (M54644BL Mechacon) is defective.
Page 10
Intermittent will not EJECT.
Fault 1: Check PCB under winding coil. Tighten earth screw.
Capstan pinch roller does not press on shaft completely, causing irregular tape run.
Fault 1: [Replaced belt of loading motor]. System adjustment switch (long black switch under drive) is
contaminated. Cleane or replace switch.
Appliance does not fully load, drum does not turn and PLAY does not function.
Fault 1: Check tension spring, item 75, is connected at both ends.
One or more incorrect or missing transport functions, loads ok.
Fault 1: Check any relevant path sensor; if all correct, check tape sensor paths to relevant microprocessor pin.
If any incorrect path sensor, check its supply then the sensor itself. In either case, check connector of CN601 on
mechacon board.
Cassette is not ejected or loading/unloading is incorrect.
Fault 1: Check screw on mechacon panel which may be loose or missing. If starting is defective, check pins 4
and 6 of cassette housing to pins 37 and 42 of IC601.
However is the loading or unloading is defective, check pins on IC602 or IC itself. Finally check the 52 relay
board pins; this will confirm if the tape end sensors, mode motor, connection path to IC601 or IC itself is
defective.
Cassette loading motor continues to run when ejecting. Laces up but no drum rotation. REW/FF attempts to start,
fails after 1 sec.
Fault 1: Check STK5481 in PSU.
Intermittently refuses to load.
Fault 1: Check the motor leads for broken strands and resolder if necessary.
No cassettes accepted. No function. Switches on by itself as soon as it is plugged in. Left reel table runs then
switches off.
Fault 1: Poor ground connections on drive board, where capstan- and reel-motor, wiper switch and reel sensor
are positioned. Fixing screws of connection board do not make a good contact. Place star washers below both
ground screws.
Eject motor continues to run although cassette already ejected.
Fault 1: Check earth connection on mechanical board. If ok, suspect belt and function control motor. Check
position of cassette compartment.
Tape speeds up for first 10-15 mins at start of a cassette. No stop function in pause.
Fault 1: Replace mechacon CPU and add resistor (1K) from pin 4 of IC601 to anode D612 to protect the IC port.
POWER SUPPLY
POWER SUPPLY
POWER SUPPLYPOWER SUPPLY
During play the appliance switches off.
Fault 1 The ground contact screw of the function switch (underside) has become loose. Retighten or resolder all
the screws.
The appliance does not switch on.
Fault 1: RP73 (BC368) in the power supply on heat sink on the base board is defective.
Fault 2: [Display is ok] Q1 or Q2 in the PSU on the heat sink on the base board is defective.
At switch on motor runs then dies
Fault 1 Mode switch not making contact reposition to cure.
Appliance accepts cassette, but after cassette is ejected, the compartment motor continues turning for awhile.
Appliance then switches off.
Fault 1: Check earth screws of the mechanism.
Page 11
Fault 2: Replace STK5481.
Fault 3: Check +5V.
Fuse F2 blows when appliance is switched on. CP4 is o/c.
Fault 1: Check D1, D2, C2, C3. If fault persists, resolder points 11 and 8 on the STK.
Appliance is dead.
Fault 1: [No display]. CP14 (47uF) in the power supply is defective.
Fault 2: Check reading on STK5481 or check by replacement. Check conditions on ICP1 and check by
replacement. Check the 45V unregulated power supply; line up is through R2, D4 and C5. Then check for any
loose deck terminal screw.
Fault 3: [No clock display]. Check mains transformer primary winding for o/c.
Fault 4: [No switched 12V supply]. Check R2 (10R) for o/c and C5 (47uF/63V) for s/c.
Appliance is dead, clock is lit.
Fault 1: Check IC1 (STK5481) for open circuit.
Switches on. No indicator.
Fault 1: Replace regulator IC (STK5481).
OTHER
OTHER
OTHEROTHER
The clock loses time.
Fault 1: Replace the clock crystal X101 and then re-adjust C102.
Fault 2: Time influenced by the 50 Herz from the mains. Solder a 100nF capacitor between pin 32 and 53 of the
IK60 and one between 1 and 2 of the IK35 on the timer module. Modify the resistor RK 38 and RK 39 to 1 KR.
Time and data are not ok.
Fault 1 Bridge pin 2 and 32 of IC IK80 (timer PCB) and pin 2 and 25 of IK25 with a 100µF ceramic capacitor.
The display does not function.
Fault 1: On timer board 15 no reset of the processor on pin 39. Resistor R6 (680R) is o/c.
Fault 2: IC101 (UPD75208) on the timer board is defective.
Fault 3: Resistor R4 (220R) on the power supply print 02 (on the print with the control IC) is open circuit.
Fault 4: Resistor R2 (1R) in the PSU is open circuit.
Fault 5: The problem comes from the PSU and control unit but is not the route for the display's power supply.
Check CN2 on the display board pin 1 and 2:4.5VAC, 3:-30V. On the timer board, check IC1 pin 3:12V and
1:5V.
The clock runs too slowly.
Fault 1 The clock is influenced by 50HZ from the power supply.
Remedy: solder capacitors of 100nF to pin 32 and 53 of IK60 and also to pin 1 and 2 of IK35 on the timer unit.
Change the resistors RK38 and RK39 to KR.
No fluorescent display but all mechanical functions are ok.
Fault 1 Check: a) Outputs from the display driver IC1. b) The voltage supply. c) The oscillator may be caused
by a faulty UPD75208CW.
Whistle from reel motor in play/record only.
Fault 1 Check IC603.
No on/off LED display, or the cassette accepted but not released.
Fault 1 Replace the STK5481 chip.
Intermittent timer: functions and cuts out.
Fault 1 Check for poor earth via screw near mode switch.
Channel system is correct. No programme display. PDC is constantly displayed.
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Fault 1: IC20 in the tuner unit has no 5V power supply. The straps JO16 to JO20 under the tuner are loose.
(connections of the right angled conductor boards).
After a few hours, display flickers and disappears completely. Timer function no longer works.
Fault 1: Replace IC UPD75208CW-030 on the timer print.
No channel display, blank raster.
Fault 1: Replace M50440-3915P on the tuning print.
Normal in playback with a cassette recorded on another appliance, cyclical noise band approx every 45 secs with
a cassette recorded on this appliance.
Fault 1: Check the FM wave form and the head switching point (check the head drum).
Intermittent fluorescent and LCD display.
Fault 1: Suspect regulator STK5481.
Display and clock are missing.
Fault 1: [30V is missing]. Check R4 (220ohm) for open circuit.
Fluorescent display is missing. Functions work.
Fault 1: Check timer IC101 (UPD75208CW).
"Time remaining" does not appear.
Fault 1: Check opto-transistor/coupler LED connections for loose earthing screw.
Clock display is missing.
Fault 1: Check R4 (220ohm) for open circuit, (30V feed).
Display is missing plus possible incorrect mechanical function.
Fault 1: Check circuit through IC1 and IC101. If accompanied by incorrect mechanical function, check function
path from control microprocessor to diaplay.
Permanently or intermittently front key panels do not work.
Fault 1: Check CN1 for dry joints.
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