How do I test my deflection transistors?

demogo

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I'm going to take apart my G08 and pull the assembly out that has the 4 deflection transistors.

How do I test them with my DMM?

Do they need to be pulled off their mounts/disconnected from the wiring?

Thanks in advance!
 
I'm going to take apart my G08 and pull the assembly out that has the 4 deflection transistors.

How do I test them with my DMM?

Do they need to be pulled off their mounts/disconnected from the wiring?

Thanks in advance!

Take a gander at this right here. Generally on vector monitors, you'll see some amount of collapse on the X or Y axis depending on which transistor failed, or total failure if they're all dead.

Whether you can test in-circuit depends on the circuit, but it's good to err on the side of removing them. It's not hard with this monitor at all, you can just unscrew them from the mounts. I haven't done a G08 yet, but the K6100 has harnesses for all the chassis transistors, so you can just pull those from the headers and test that way.

Make sure they aren't shorted to the frame after (re)installing! Check continuity from the casing of the transistor to the frame — there should be none. If there is, make sure the legs aren't touching the edges of the frame holes they go through, and your insulator is good.
 
Thanks.

I ran across a G08 FAQ that has been very helpful and it even lists how to check the transistors from the cables they hook to.

Unfortunately my readings didn't agree at all with the numbers that were presented in the FAQ and were off from what your link said as well.

I swapped cables for the deflection transistor pairs and was shocked to see that the video was back on the game so they must be working okay but I can't explain why my testing was off.
 
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