Grundig GV 6400 HiFi/5 Service Manual page 16

General Section
Having called up this adjustment level, set the noise voltage of the left
channel with the button "-" or "+" to minimum. Each time one of these
buttons is pressed the level changes by 0.1dB and the set value is
stored in the EEPROM. The value "0"..."49" is indicated on the display.
Level 62: Standard Sound Playback Level of IC7100 (PAF-AF)
The standard sound playback level needs adjusting on replacement of
IC7100 on the Family Board II or of the EEPROM (IC7890 on the
Family Board).
Preparation before calling up this level:
– Connect the AF millivoltmeter to the EURO-AV1 socket, contact 1
– Feed in a sound signal (1kHz sine, 0.7V
contacts 2 and 6.
– Record the sound signal.
Having called up this adjustment level, play back the recorded sound
signal (standard sound playback) and set the output level with the "-"
± 50mV. Each time one of these buttons is
or "+" button to 500mV
rms
pressed the level changes by 1dB and the set value is stored in the
EEPROM. The value "0"..."15" is indicated on the display.
Level 99: Timer Clock Output
For adjusting the timer clock at this level (Level 53), the timer oscillator
frequenacy (approx. 2048Hz) must be measured at plug contact 1921-(19)
"HEST" of the keyboard control (PDC) (resolution: 6 digits at least). Note
it down (f ).
mess
Note:
On selection of this level, the display is dark and no function of the VCR
is active. This level and the service test programme can be terminated
only by disconnecting the VCR from the mains.
Conversion Table Dual / Hexadecimal
right hexadecimal digit
0 1 2 3 4 5 6 7 8 9 A B C D E F
0
000 001 002 003 004 005 006 007 008 009 010 011 012 013 014 015
1
016 017 018 019 020 021 022 023 024 025 026 027 028 029 030 031
2
032 033 034 035 036 037 038 039 040 041 042 043 044 045 046 047
3
048 049 050 051 052 053 054 055 056 057 058 059 060 061 062 063
4
064 065 066 067 068 069 070 071 072 073 074 075 076 077 078 079
5
080 081 082 083 084 085 086 087 088 089 090 091 092 093 094 095
6
096 097 098 099 100 101 102 103 104 105 106 107 108 109 110 111
7
112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127
8
128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143
9
144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159
A
160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175
B
176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191
C
192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207
D
208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223
E
224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239
F
240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255
1 - 16
) to EURO-AV1 socket
rms
2. Special Functions
Continuous Operation Test
The continuous recording and playback test is part of the service test
programme. A discovered fault is stored in the EEPROM and is saved
even if the VCR is disconnected from the mains.
Calling up the Continuous Operation Test
– Start the continous test with button
Terminating the Continuous Operation Test
– Press (STOP) button or
Cleaning the Headwheel
The video heads are cleaned briefly during the video tape is threaded
in. By pressing the "TRACKING" button (min. 5s) the cleaning in play
mode can be activated for approximately 10s. In doing so, the tape
transport is stopped and the video head cleaning roller is pressed
against the headwheel. Afterwards, play is continued.
Erasing the RAM and EEPROM
While connecting the machine to the mains, press and hold the
"STANDBY" button on the local keyboard for at least 5s.
The EEPROM and the internal processor RAM are erased and
initialized. In doing so, the customised station memory and the timer
data are erased. The specific data of the VCR, the tape deck param-
eters, VCR option codes, and the adjustment values remain un-
changed.
Replacement of the EEPROM IC7890
Attention: On replacement of the EEPROM, IC7890, the machine
must be readjusted according to the Levels 51, 52 (op-
tional), 53, 60, 61 and 62 and the VCR option code Level
40 must be entered.
GV 6400 ..., GV 6401 NIC
(Record) or (Play).
"STANDBY" button.
GRUNDIG Service