Repair Preparation - Vector G08 Series Faq

REPAIR PREPARATION

So you have a G08, and you have no idea of its condition. Well, let's do a few basic things before
we fire it up ("fire it up" might be a poor choice of words here ;-)).
1) Start by dismantling the monitor.
First, discharge the monitor tube. There is high voltage under the monitor's anode cup if the
monitor has been powered up recently. It may not be necessary to discharge a monitor tube that
has been sitting for a while, but it is best to be on the safe side, so get in the practice of always
discharging a monitor tube before you begin work on a monitor.
There are many ways to discharge a tube. The recommended way is via a High Voltage probe.
Connect the ground of the HV probe to the monitor chassis, and insert the probe end
underneath the anode cup and watch the voltage go to 0 (do not touch the chassis during this
procedure). However, as some people may not have access to a HV probe, a cheaper (but less
safe) alternative is provided below.
Place the monitor on a non-conductive surface. Do not touch the monitor with your hands while
doing this procedure, as we will be discharging the monitor to the monitor chassis. Locate the
anode cup; it is the suction cup thingy attached to the tube that has a red wire coming out of it.
A few inches from it, there is a metal shield that surrounds the back of the tube. We will be
discharging the tube to this shield.
Insert a long screwdriver with a plastic handle under the anode cup, and tilt the screwdriver
such that it also makes contact with the metal shield. There should be a few quick snaps. Hold
the screwdriver there for a second, and then you are done.
Next, remove the neck board, as bumping it may cause you to break the tube's neck. Getting
the neck board out of the way will keep you from accidentally bumping it when trying to reach
other parts. Next, unsolder the wire that goes from the back of the focus knob to the neck board.
This is required in order to separate the HV unit from the deflection board. Everything else is
connectorized and screwed together, so it should be easy enough to take the monitor apart.
Make sure you have removed the neck board from the tube before removing the 10-pin
connector on the HV unit! Trust me, you are less likely to break the tube's neck this way.
2) Check the deflection transistors.
Visually inspect the transistors and make sure they are even the correct transistor type. I have
seen operators attempt to substitute other types of transistors for the 2N6259s or MJ15003 /
MJ15004, so make sure they are correct to start out with.
G08 Vector Monitor Guide
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