Abgleich / Adjustment ProceduresGV 5000 �, GV 5300 �
2.2 Family Board � Frontend (FV)
Test equipment: Oscilloscope with 10:1 Test Probe, Voltmeter, Colour Generator
Service work after replacing the Tuner:Adjustments no. 2
AdjustmentPreparationAdjustment Procedure
1. Vision Demodula-Feed in 38.9MHz / 100mVPP into the tuner output 1701-(17).Set the voltage with F5770 (AFC) to 2.5V ?0.2V.
tor Circuit, F5770Voltmeter: ..................................................... IC7772-(10)
EE-mode.
2. Delayed AGCFeed in a PAL white test pattern with sound carrier (withoutSet the amplitude with R3770 (AGC) to 550mVPP +0/-50mV.
Voltage, R3770sound modulation, UHF-range, Ch24, 67dBmV aerial signal)
into the warmed-up VCR.
Oscilloscope: ......................................... Tuner 1701-(17)
EE-mode.
2.3 Family Board � Video/Chroma (VS)
Test equipment: Oscilloscope with 10:1 Test Probe, Frequency Counter, Colour Generator
Service work after replacing the Family Board: �
AdjustmentPreparationAdjustment Procedure
1. FrequencyAV recording (do not feed in an signal).Set frequency counter with R3054 (Sync. Frequ.) to 3.8MHz
Deviation Sync Frequency counter: ............................................?10kHz.1911-(2)
Value, R3054
2. Chroma Writing Connect IC7051-(2) to +5V.Set Chroma signal with R3038 (CHROMINANCE WRITING
Current, R3038Oscilloscope: ......................................................CURRENT PAL) to71m V (-12.5dB of the FM-signal).1911-(2)
PP
Feed in a PAL red raster test pattern with 75% saturationDisconnect IC7051-(2) from +5V.
(ratio burst: chroma = 1 : 2.2).
AV recording.
2.4 Family Board � Standard Sound / Audio Linear (AL)
Test equipment / aids: AF Millivoltmeter, AF Generator, Video Cassette of reputable brand.
Service work after replacing the Family Board or the RP-Head: Adjustment no. 1.1, 2
AdjustmentPreparationAdjustment Procedure
1. Erase FrequencyFrequency counter:.............................................With F5603 (BIAS Frequ.) set the reading on the frequency1918-(7)
70kHz, F5603Recordcounter to 70kHz ?10kHz.
1.1 Bias (70kHz), AF millivoltmeter: ...................................................Set the voltage drop across R3600 with R3600R3618 (BIAS) to
R3618Record.15mV.
rms
Check the frequency response.
1.2 Frequency�Connect IC7601-(10) via 270W resistor to ground.The voltage ratio of 400Hz to 8kHz must not be higher than
Response Test �Feed in a CCVS signal via EURO-AV socket, contact 20.1:0.7 or 0.7:1 (?3dB). If the voltage ratio exceeds these
�Feed an audio signal of 200mV (480mV ) from the AFlimits, the bias must be altered:
rmsPP
generator to the EURO-AV socket, contact 2 or 6.To increase the playback voltage at 8kHz: Reduce "BIAS".
�Make a recording of 400Hz and 8kHz each of 1 min atTo reduce the playback voltage at 8kHz: Increase "BIAS".
least. Afterwards play back these recordings.Remove the 270W resistor between IC7601-(10) and
�Connect an AF millivoltmeter (oscilloscope) to EURO-AVground.
socket, contact 1 or 3.
2. Playback Level,AF generator (1kHz / 0.7Vrms):Set output voltage with R3606 (PB-Lev.) to 0.5Vrms ?50mV .
R3606..................................... EURO-AV socket, contact 2 or 6
AF millivoltmeter: ......... EURO-AV socket, contact 1 or 3
Record (Normal Play).
Play back this recording.
3. Keyboard Control Unit (ODCG1)
Test equipment: Frequency Counter
Service work after replacing the Keyboard Control Unit:�
AdjustmentPreparationAdjustment Procedure
1. Clock, C2005Disconnect from the mains.The period is set with C2005 (CLOCK ADJ.) to 488.281,25ns
IC7101: ....... Connect Pins 67 and 68 with Pin 33 (+5V).?0,715ns by the manufacturer.
Frequency Counter: ............................................Disconnect IC7101-(67), -(68) from +5V (Pin 33).1101-(1)
Reconnect to the mains.
3 - 4GRUNDIG Service |
ACEC
GRUNDIG
