G'day mates. First time posting.
I'm repairing a 1974 Williams Strato Flite. In general, nearly all the game functions are working. I have two related features that do not yet work. The ejector at the top of the playfield is stuck on Open Bottom Gate. It doesn't cycle through the 5 different steps. The bottom gate does open and light up properly, so game play is not affected that much. I would like to fix it so the ejector does advance. The Top Gate, which is one of the other ejector options, does not open, even when directly triggered on the playfield. I cannot figure how to test the Number Match Unit to know whether that is not advancing, or there is some other part to look at. I also don't know that if the top gate is the real problem, so whether to just go ahead and replace that first. I do have the schematic and manual. Any approaches to diagnose and repair are whole-heartedly welcome. Thanks.
Matt