Troubleshooting guide

Cinematronics Vector Monitor Repair Guide v.1.0
Page 19 of 53
HIGH VOLTAGE SUPPLY
The Cinematronics monitor was manufactured with two slightly different HV designs. The first
design – the ‘discrete’ design for lack of a better description - was used on all games up to Star
Castle (Rev. A to F). The discrete HV monitor utilizes the right half of the monitor PCB for HV
generation. The High Voltage Transformer (“HVT”) and Voltage Tripler are placed at separate
points on the PCB and covered with a gold anodized protective cage. Starting with Star Castle,
Cinematronics utilized an all-in-one HV module commonly referred to as the ‘Keltron’ after the
manufacturer. To further confuse things, Cinematronics used two different HV modules in
production, one was the larger gold anodized aluminum manufactured by Keltron, while the other
was a smaller black box with a couple of studs sticking out of it for mounting which was
manufactured by PTK. The PTK black boxes have a lower voltage output of 15KV versus the
Keltron’s 16KV, resulting in a slightly dimmer image on the display.
According to "Joe the Cine Tech," the monitors were originally designed for the lower voltage
black boxes. Someone in the company just ran across the Keltron units (which were designed for
some medical equipment) and gave them a try. Since the lead time on the black boxes was
ridiculous, and Keltron was much more eager to work out problems with connectors etc, they used
Keltron as much as possible, switching to the black boxes when the Keltron supplies ran low. There
is some sort of adapter that plugs in between the molex connector and the back box units. The PTK
black box HVs used 15KV for the desired output, so I would guess the "adapter" was a resistor to
drop the output to 15 KV.
Cinematronics part # 82-10841-01
Cinematronics part #??? 82-11083-01
Keltron Part # HP160124A
Black Box # ____??______
Rev.A and Rev.B Monitors
There is a significant amount of circuitry added to the power-supply sections between the Rev.A
and Rev.B versions of the monitors with the discrete HV section. Rev.B is an "enhanced" version
of the Rev.A monitor. This monitor was used in Starhawk, and has some additional circuitry in the
power supply section. This revision also has a 7805 regulator added, to generate +5V for the logic
chips from the +25V input, instead of relying on the +5V from the CPU board. The Rev.B
additions were carried through to the Keltron-type design (a.k.a. "Rev.G", according to the
draftsman's block in the corner). Check the schematics for any specifics you require.