Grundig TVR 3710 GB Betriebsanleitung Seite 38

Adjustment Procedures
3.3 Signal Chassis – Deck Control / Deck Electronic (DE)
Test Equipment / Aids: Test Cassette
Alignment
1. Head switching Load the test cassette and call up the Service Function:
position (GAP) – Press button
¢ (playback) on the local keyboard and hold them down for
5s at least.
– With button G on the remote control call up the "SERVICE
CONTROL" function.
– With button ]| on the remote control call up the "GAP
POSITION" function.
3.4 Signal Chassis – Frontend 2 (TU2)
Test Equipment / Aids: Digital Voltmeter, Oscilloscope
Alignment
1. Demodulator Connect tuner 1301-(5) to GND.
circuit Digital voltmeter: ....................... tape deck – IC7410-(61)
PAL, L5303 Reception: PAL-BG
(AFC2)
Colour generator 38.9MHz, 35mV
SECAM-L, Reception: SECAM-L, band 1 (channel 04)
R3322 Colour generator 33.95MHz, 35mV
(L´ADJ2)
2. Start-up of the R3341 "fully clockwise"
tuner control Feed in a white test pattern without sound carrier (UHF range,
voltage channel 24, 67dBµV aerial signal) into the warmed up TVR.
R3341 Oscilloscope: .......................................... tuner 1301-(17)
(AGC2)
3.5 Signal Chassis – Video/Chroma (VS)
Test Equipment / Aids: Blank Cassette, Oscilloscope with 10:1 Test Probe, Frequency Counter, Colour Generator
Alignment
1. Sync frequency AV recording without input signal
R3010 Frequency counter: ............... connector contact 1902-(2)
(SYNC-FREQU.)
2. Chroma recording Connect IC7051-(2) via 150Ω and 22µH to +5V supply.
current Oscilloscope: ........................ connector contact 1902-(2)
PAL Feed in a PAL red raster test pattern with 75% saturation
R3029 into the AV socket and record it.
(PAL-CURR.)
SECAM-L Feed in a SECAM-L red raster test pattern with 75%
R3027 saturation into the AV socket and record it.
(SECAM-CURR.)
3.6 Signal Chassis – Standard Sound (AL)
Test Equipment / Aids: Blank Cassette, AF Voltmeter
Alignment
1. Bias (70kHz), Record any signal.
R3618 Measure the voltage drop on R 3600 with AF voltmeter.
(BIAS)
1.1 Frequency – Feed in a CCVS signal via AV socket, contact 20.
response – Feed an audio signal of 50mV
the AV socket, contact 2 or 6.
– Record the 400Hz and 8kHz signals each for 1 min at
least. Afterwards play back these recordings.
– Connect an AF millivoltmeter to the AV socket, contact
1 or 3.
2. Playback level Sound generator (1kHz / 0.5V
R3606 ................................................. AV socket, contact 2 or 6
(PB-LEVEL)
Record (Normal Play).
Play this recording back.
3 - 6
Preparation
¢ (STOP) on the remote control followed by
Preparation
to tuner 1301-(17)
rms
.... tuner 1301-(17)
rms
Preparation
Preparation
from the AF generator to
rms
): ....................................
rms
TVR 3710 ..., TVR 5100 ..., TVR 5500 ...
Alignment Procedure
Play back the test cassette and press one of the buttons
on the remote control.
On successful alignment the TVR switches to stand-by.
If the procedure was not successful, the TVR ejects the test
cassette.
Causes: Test cassette, headwheel or technical defect
(e.g. µC)
Alignment Procedure
With L5303 set the voltage to 2.5V
(AFC2)
With R3322 set the voltage to 2.5V
(L´ADJ2)
Remove the ground connection.
With TDA9800T/V3 (IC7300) fitted:
With R3341 set the voltage to 500mV
(AGC2)
With TDA9812T (IC7301) fitted:
With R3341 set the voltage to 400mV
(AGC2)
Alignment Procedure
With R3010 set the frequency to 3.8MHz
(SYNC-FREQU.)
±
10kHz.
With R3029 set the chroma signal to 85mV
(PAL-CURR.)
(-12.5dB of the FM signal).
With R3027 set the voltage to 55mV
(SECAM-CURR.)
of the FM signal).
Remove the150Ω resistor and 22µH coil.
Alignment Procedure
Adjust voltage drop on R3600 to 15mV
Check the frequency response.
The voltage ratio of 400Hz to 8kHz must not be higher than
1:0.7 or 0.7:1 (±3dB). If the voltage ratio exceeds these
limits, the bias must be corrected:
To increase the playback voltage at 8kHz: reduce "BIAS".
To reduce the playback voltage at 8kHz: increase "BIAS".
With R3606 set an output level of 0.5V
(PB-LEVEL)
x c
/
±
0.2V.
±
0.2V.
-1dB.
pp
-1dB.
pp
pp
(-17dB
pp
with R3618 .
(BIAS)
rms
rms
GRUNDIG Service