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Voltage output on pins for 1980's monochromatic monitor


Aug 12, 2016
Aug 12, 2016

I have a vintage 1981 audio analyzer from the Netherlands. It uses a custom CRT monitor that I do not have access to.


I want to test the pins on the monitor plug and determine if they are providing a good signal. The device turns on, fan starts, I can detect voltage on the various internal cards.

Inside the computer there are 3 pins that go from the "Graphics card" to a DB-15 plug.

These are the white/blue/yellow wires on the bottom of the photo: IMG_0015.JPG

These 3 wires to go a DB15 plug on the back of the computer labeled CRT MONITOR.

When I attach my DMM ( 388-HD ) to the 3 pins that are attached to the card, I get

PIN1: .3VAC (.06VDC ) .120 Khz
PIN2: .03VAC (.00VDC )
PIN3: .04VAC (.00VDC )

1) What would appropriate voltages be?
2) Am I able to measure these using my DMM ( I read that low HZ signals could be problematic )
3) Aside from plugging in a matching CRT, is there anyway to determine some basic level of functionality?

Any help appreciated!