Just picked up an Enchanced IIe, and it has a wierd problem - pretty low video output, and a bit fuzzy, connected to my Apple Monochrome monitor. My other IIe is crisp and much brighter. Any idea where to start troubleshooting?
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Start with the RCA connector. Wiggle, twist and re-solder if it's intermittent. Otherwise, check 74LS10 at C5 as well as the video amplifier VA1.
Does it exist? I've never even seen a picture of an Apple IIe motherboard that has the VA1 footprint populated.
Yeah, I've only seen a similar part on the //c and //c+. But it looked like some of the //e's were provisioned for something like this. Maybe never implemented though.
Well, I don't have VA1, and I replaced the 74LS10 with my good one, and no change... The connector is fine, wiggling doesn' t change anything, but I did resolder just in case.
Check all the voltages on Q1 and Q2 (they are measured against ground):