Spark Gap Question

Hi so I have a older CRT monitor I am working on recapping at the moment and I noticed these burnt out components on the crt socket board. I looked into the service manual and they are Sankosha Spark Gaps: SKO 20-59003-00301. I am confused by what value they should be for replacement purposes as its not mentioned anywhere. I know the more current component is a gas discharge tube but again I don’t know the value. Any help would be appreciated!


My searches are turning up nothing, and that character string doesn’t much resemble those that the supplier is listing currently. Given a schematic, one could probably make some pretty reasonable inferences about replacement parts based on expected circuit voltages and the limitations of the protected devices.

I expect that “spark gap” is simply a reference to a GDT, rather than referencing some other component. The DK offerings for such are here.

Here is the service manual. I am not that experienced at reading voltages and schematics. If you can see this attachment do you think you could let me know what you think?

TM1416_2016_service.pdf (2.5 MB)

Methinks you grabbed the wrong number: the Y08Z-230B one looks more appropriate. 2045-23-BLF would appear to be a plausible alternative.

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Ah yeah you are right that part number sounds better. 230v is what is required based on the schematic?

It’s what the part number suggests, and the upper tolerance on that figure lands just below the 300V VCE(MAX) of the 2SC3790 they’re connected to.

The extra tasty crispy state of these GDTs may indicate a need for replacement of things beyond a few caps, as they’ve clearly not been performing to spec lately…

Ill tell you exactly what I know so far. This is from 1992 and is a professional monitor that was used in a school very infrequently from what I was told. When I powered the crt first on I was getting a distorted flyback noise and normal power leds on the main board. I pressed degauss and I could hear it faintly. I checked the fuse on the back of the crt monitor and it was in fine condition. When I opened up the crt those 4 components were a bit melted to the neck board. I have since removed them. One of them is actually in pretty good condition (its clear instead of black) but I took it out still. I then took the main board out and noticed a few blown caps near the power supply and also 2 burnt transistors with another 2 burnt resistors in the same area. I have reflowed solder to the flyback transformer as well as the other transformers in the area. I have heard that the tube itself might be shorted but I would like to try a recap/remake none the less.