I am looking to replace Q2 in a Gottlieb System 1 power supply. The parts list calls out MJE340K. I am trying to find out what the K suffix means. I have found lots of info on transistor coding, but nothing regarding the suffixes. I have access to an MJE340G but not sure if that is an acceptable replacement. I have also read the TIP85 is an acceptable substitute. But my question is....what does the suffix designate?

Thank you for the explanation!!

Not only do I believe I have an original System-1 power supply from Gottlieb, but the service manual I have and the drawings and parts list (attached) show Q2 to be a MJE340K.

So you are saying I shouldn't use what my drawing shows?

Also, my mistake....I meant NTE85 not TIP85. Can I substitute TIP85 for 2N3416. All this electronics stuff has me rattled! Thanks for the help.

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Here is my board. CR10 is currently missing because I am replacing it.

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Here is schematic showing the rest of the circuit. I see other resistors are different than other schematic versions (R16, R17). Now I have even more questions about substitutions. Are Q2 parts interchangeable....MJE340k vs TIP31c? Should I change resistors? Are there any other substitutions for Q3, 2N3416?

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I replaced Q2 with TIP31C and now have all correct nominal voltages! Thank you!!! So I will be powering up the rest of the game for the first time shortly.

So I've connected the power supply to the CPU board and am following Clay's guide regarding powering up the game for the first time. I'm going to create a new topic about the problem I am now experiencing, and hope you can help me along there too. I think this thread is solved.