I was very glad recieving the service manal from You. Additionaly very fast. Extremaly nice servicing. Thanks very mach! Now my GX-220 working better, than it was made. Alexander from Moscow, Russia/
Sweet! I won the item on eBay and couldn't adjust the geometry or even keep a steady picure. This guide has the full schematics (not available anywhere else as far as I could tell), and was a bargain for the wealth of knowledge it contains. I hooked it up to my testing equipment, tweaked a few potentiometers and got it playing videogames in no time. Thanks!
Great Manual! It contains all the wiring schematics and mechanical exploded views that are essential for service and repair. I was surprised I even found this for such an old machine. Only wish I knew of this site many years ago.
Text excerpt from page 7 (click to view)
Alignment and Adjustment
2-2 Mechanical Adjustment
Note : Refer to the Mechanical Manual �DX-9R (AC68-00001A)� for the adjustment and confirmation of ass�y full deck.
2-2-1 The number and position of test point
Test point : TP601 (Control Pulse) TP602 (H�D S/W -Trigger) TP301 (Envelope) TP302 (Audio output) TP303 (Video output)
AUDIO OUTPUT ENVELOPE HEAD SWITCHING
Fig. 2-3 Location of Test point (Main PCB-Top View)
2-2-2 ACE Head Position (X-Point) Adjustment
(See the 2-2-1(d) ACE Head Position (X-Point) Adjustment on page 2-2 of the Mechanical Manual) 1) Playback the alignment tape (Color bar). 2) Press the �SW718 (TEST)� button on Main PCB to set the adjustment mode. (See Fig. 2-2) 3) Press the �5� button of remote control then adjustment is operated automatically. (See Fig. 2-1)
4) Connect the CH-1 probe to TP301 (Envelope) the CH-2 probe to TP602 (H�D switching pulse) and then trigger to CH-1. 5) Insert the (-) driver into the X-Point adjustment hole and adjust it so that envelope waveform is maximum. 6) Turn the Power off.