For example :- 0A 1F shows parameter ten ( 0A hex) at
SERVICING
value thirty one (1F hex)
Use the programme up and down keys to change the
ADJUSTMENTSADJUSTMENTSparameter number, and the volume up and down keys to
In order to make service adjustments the TV should have aadjust the value of the current parameter ( local or hand unit
suitable signal tuned in; ideally, a geometry test card. To setcontrols ).
OSD contrast, a teletext signal is recommended.The volume control adjusts the settings only within the valid
The controller has a service mode of operation whererange ( lower six bits ). Keys 1 and 2 on the hand unit are
adjustments are made and configuration options set. Toused for other adjustments. Do not press 1 or 2 except
enter service mode, place a shorting link across thewhere indicated in the notes below.
terminals of PL701 or ground IC701 pin 12. Note, to use theTO STORE THE CHANGES, PRESS THE ?TV? KEY ON
normalise key or change programmes, as required for someTHE HAND UNIT BEFORE REMOVING THE SERVICE
adjustments, it is necessary to exit service mode byMODE LINK. If this is not done, certain changes may be lost
removing the link.when the TV changes channel or is switched off. The word
In service mode, the display shows two 2-digit hexadecimal"STORED" appears at the top left of the screen when the
numbers on the left of the screen; the left hand one is theadjustments are saved.
service parameter number, the right hand one is the value
for that parameter. Some parameters are identified by a two-Service parameters 01 to 16 apply to the control registers of
letter code instead of a number, see below.IC504 as shown in the following table.
N° Default Value Function Action
00 02 System control Do not adjust
01 D0 System control Do not adjust
02 1F Hue (SCART NTSC 4.43 playback only) Use picture menu control instead
03 13 Horizontal shift Adjust to centre picture horizontally
04-07 00 E-W control Not used on this chassis
08 25 Vertical slope ( linearity ) Adjust for vertical linearity
09 09 Vertical amplitude ( height ) Adjust for correct picture height
0A 5F S correction Adjust for best vertical S-correction
0B 1B Vertical shift Adjust to centre picture vertically
0C 1F White point - Red
0D 1F White point - Green See notes below
0E 1F White point - Blue
0F 08 Peaking (sharpness) Use picture menu control instead
10 1F Brightness Use picture menu control instead
11 9F Saturation Use picture menu control instead
12 20 Contrast Use picture menu control instead
13 34 AGC take over point See notes below
14 40 FM sound volume Set to 40 hex
15 3F IF PLL ( AFC ) adjustment See notes below
16 00 Vertical zoom Not used on this chassis
Parameters above 16 are designated by two letter codes (except text contrast). These control configuration and have limited
ranges.
Text contrast - changes to teletext mix
Text mode FFSet as preferred, see note below.
mode
Ph 01 Headphone option (affects audio menu) 00 if no headphone socket, 01 if fitted
Ex 00 Export ( VHF/UHF ) setting 00 for UHF only, 01 if multiband tuner
00 Single SCART
AV 01 AV socket configuration01 Single SCART plus Phono inputs
02 Dual SCART
Stereo chipset indicator, not adjustable, if
St 1010 Zweiton (A2) Audio System detected
00 Audio IC failed.
Set to give correct audio levels on Scart
G1 00 Level Adjust
Outputs
G2 00 Stereo Adjust Set to give maximum Stereo separation
N- 07 NICAM Error Rate Un-mute Not used on this chassis
N+ 30 NICAM Error Rate Mute Not used on this chassis
If possible, it is advisable to make a note of the existing values prior to commencing servicing.
HT setting :junction of D814/CE817. Press the normalise key to restore
Reduce brightness and contrast to minimum, using the onbrightness and contrast to the mid-point settings.
screen picture menu (service link not fitted), and press the
TV key to clear the OSD Adjust RV820 for 115?0.5V at the
15 |
ACEC
HITACHI
