I'm going slowly insane with the sound on a Paragon that I have been bringing back to life. The first odd thing is that it has a 2518-32 instead of a 2518-50 sound board, so I am assuming that I might not get the right sounds, but for now I can live with that.

I've been following the great guide at http://www.pinball4you.ch/okaegi/rep_soundold.html and replaced many of the capacitors on the board and have good voltages and an almost square wave out of the programmable frequency generator part 1 (2.2us at 5.03V). However, when I get to the Tone Trigger Generator things get a little wonky. I can see 4.87V on one side of C14, but when I look on the other side of it (as well as the base of the transistor) I see basically nothing which also means I don't see any signal coming out of the 555.

I've replaced all most of the capacitors on that side C14, C19, C20 as well as the 555 and Q2 (but I used a 2N2222 instead the 2N3904). I've verified that R19 and R20 are reading pretty close to 10KΩ.

Incidentally if I touch part of the board, I am picking up a radio station loud and strong, so I know that the amplifier portion of the board is working pretty good.

Any suggestions for what else I need to look at?

I also have to ask if I am wasting my time bringing the board back to life and should get a 2518-50 (or modern equivalent) because I won't have the right sound rom?

Thanks in advance!

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