Introduction - Vector G08 Series Faq

G08 Vector Monitor Guide

INTRODUCTION

Ok, enough making fun of the G08 :-). It is actually a pretty strong monitor considering the work
that it does, and when it is working it is a fairly impressive color vector monitor. There are horror
stories about this monitor, and most of them are true (and the list is long), but on the other hand,
there are others have had theirs for 15 years without it breaking down once. Before working on
your G08 monitor, read through this entire document, and be certain you have schematics for
additional review.
Acknowledgements
The following people have contributed to the development of this document: Mark Jenison; David
Shuman; Michael Kelley; Al Kossow; Roger Boots; Zonn Moore and David Fish.
DISCLAIMER
CAUTION!!! LETHAL VOLTAGES ARE PRESENT IN ARCADE MONITORS.
SUITABLE PRECAUTIONS SHOULD BE TAKEN BEFORE ATTEMPTING TO
SERVICE YOUR MONITOR. REMEMBER, NO WARRANTIES, EXPRESS OR
IMPLIED, ARE GIVEN. USE THIS INFORMATION AT YOUR OWN RISK. I AM NOT
RESPONSIBLE FOR ANY DAMAGES THAT MAY OCCUR TO YOUR PERSON OR
PROPERTY.
The Electrohome G08 is the monitor that was used in the Sega/Gremlin color vector games Space
Fury, Eliminator, Zektor, Tac/Scan, and Star Trek and in the Cinematronics game Cosmic Chasm.
The Electrohome G08 monitors, like other vector monitors, were notorious for their failure rate.
There were a few different versions of the G08 monitor in an attempt to evolve towards a more
reliable design.
The first model of the Electrohome G08 monitor was the G08-001. Since Space Fury was
Sega/Gremlins first color vector release, one might find this monitor in an early production Space
Fury. The monitor, however, must have been very prone to failure, as in the initial manual there
already was a "future" version already being worked on. The G08-001 monitor used MJ15003 and
MJ15004 deflection transistors and had direct connections from the deflection transistors to the
deflection board. Sega determined that t h e problems encountered with the G08-001 were centered
around the deflection amplifiers. Underrated power transistors combined with an extended "on"
time during the power-up routine resulted in damage to the amplifier circuit.
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