Batboard

I know that I should probably toss this relic in the scrap heap, but it's only used for on for a signal source for aligning ham equipment front ends. I hate to have to buy a new signal generator, but maybe it's time!

When I power on the monitor, I get a loud hum and the synthesizer will not lock up. It looks and sounds like a power supply issue. There are 4 test points on what appears to be a regulator board. The board is located in the center bottom of the monitor. I get -5v on the green test Jack, +15v on the blue, -23.7v (250 mv ripple) on the purple, and +5v on the red Jack. Maybe the -23.7v is supposed to be -15v? The adjustment pot next to the purple test Jack has no affect on the output.

Anyone got a schematic for this oldie?

Thanks.

Pierre

Update - found schematics online. The -15 volt pass element had shorted out and took the LM317 regulator chip with it. I jury rigged a temporary Zener pass regulator to see if anything else was toast. That power supply has no over-voltage protection, so when it went, it killed the deviation scope module. The deviation scope has a potted board at the end of the CRT that has a strong essence of ohmite. The rest of the monitor works OK.

Anyone got a junker S1327A monitor that they would be interested in parting with, or at least the scope module? Drop a line if you have one that you may want to sell.

Pierre

The high voltage for your scope is -1500 VDC. That is what that black module is supposed to do. It was replaced with a board that had discreet components (step-up transformer, filtering caps, etc.). It should be fairly easy to come up with something to replace the module. Unfortunately, I don't have the schematics to the replacement.