HARMAN - KARDON HRD180 Service Manual

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.

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.

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.

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.