Service manual

Wells-Garnder Color Vector Monitor Guide
Page 14 of 73
You may want to leave the game plugged in BUT TURNED OFF for this step so that you can
ground to the earth instead of just the chassis. If you plan to remove the HV unit, you must
disconnect the secondary anode from the tube, which is a little tricky if you have never done it.
Under that suction cup is a double-barb connector. The barbs extend perpendicular to the wire as
it enters the suction cup. Simply pinch the suction cup as best as you can and wiggle it back and
forth while pushing in at the edges and pulling out at the center. It will eventually come off. Here
is a cut-away depiction of the anode; the wire will run perpendicular to this view (i.e.,
towards/away from the reader):
| /\ /\ |
\ \ / /
\____|_|____/
WARNING: That picture tube is a bomb! When it breaks, first it implodes, then it
explodes. Large pieces of glass have been known to fly in excess of 20 feet in all directions.
DO NOT carry it by the long, thin neck. Discharge its voltage to ground by shorting the
anode hole to ground.
CHASSIS TRANSISTORS
There are two types of the large chassis deflection transistors on the Wells-Gardner 6100. They
are the six large TO-3 package transistors mounted to the chassis ("package" refers to the
physical description of the transistor, NOT the electrical characteristics). The three NPNs are
2N3716s and the three PNPs are 2N3792s, which are all in the final stages of the deflection
amplifiers or the power supplies. The deflection amps are like an audio push-pull amplifier and
to power these amps the monitor takes AC in and produces plus and minus DC voltages.
• 2N3716 (NPN); widely available replacement is NTE284
Q705: +X (right) for horizontal; +Y (top) for vertical
Q605: +Y (top) for horizontal; -X (left) for vertical
Q102: output positive (+) power supply
• 2N3792 (PNP); widely available replacement is NTE285
Q706: -X (left) for horizontal; -Y (bottom) for vertical
Q606: -Y (bottom) for horizontal; +X (right) for vertical
Q103: output negative (-) power supply
SPECIAL NOTE: Q705 and Q102 lie in such close proximity that it is not uncommon for their
respective transistor sockets to be switched at some point, which obviously swaps the
corresponding functionalities (symptoms).