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SE/30 - new analog board - Single Point of Light Video
Posted by: massiverobot on 2015-06-08 06:40:23 Hello- I'm fixing my SE/30- I swapped in a new tube from a good SE and a new re-built analog board. I power it up now and I get a nice startup chime, but the video is just a single point of light. I checked connections and things look ok, what is going on?
Posted by: Macdrone on 2015-06-08 07:25:45 Recap the motherboard. Also the se30 board would have slid right into the SE so you could have tested it that way. Do a search SE30's are some of the worst for cap goo and battery leakage damage. Capacitors leak, rot traces and the goo is conductive so it causes even more issues.
Posted by: olePigeon on 2015-06-08 08:06:32 Double check and make sure the RGB cable from the analog board to the motherboard is connected.
Posted by: 360alaska on 2015-06-08 09:00:51 If it's a single point of light and NOT A LINE then check your yoke/yoke connector... and if you don't know... The yoke is this guy: Make sure it's fully installed on the CRT...
Posted by: olePigeon on 2015-06-08 09:25:10 Oh, right. Maybe it was that cable. I'm sure 360alaska is right. In any event, double and triple check your cables. I ran into this exact same problem, then I noticed the cable was unplugged. 😛
Posted by: uniserver on 2015-06-08 09:47:32 Pretty sure a single point of light means you forgot to connect your deflection cable to the analog board or capacitor c15 is completely blown
Posted by: uniserver on 2015-06-08 09:48:18 You can check out the dead Macscrolls it's on my website
Posted by: massiverobot on 2015-06-08 10:59:03 Recap the motherboard. Also the se30 board would have slid right into the SE so you could have tested it that way. Do a search SE30's are some of the worst for cap goo and battery leakage damage. Capacitors leak, rot traces and the goo is conductive so it causes even more issues. Yeah, uni has already capped the mobo. It's been working fine. I'm just putting in a better analog board and tube now. I'll check the yoke and the deflection cable- that is the red cable right? The tube is from one system, the analog board is from another- it's all going together into the SE/30 case so that is where I am putting this together.
Posted by: 360alaska on 2015-06-08 12:22:26 Look at P1 map.bmp
Posted by: massiverobot on 2015-06-08 14:55:50 OK, it was the yolk. I, uh, forgot to plug in it's giant power plug back into the analog board- it was close, but not plugged in. So that is what it looks like with no power to those magnets- just a bright point of light in the middle of the screen 🙂 It's all good now. I'll make a fresh post with picts.
Posted by: uniserver on 2015-06-08 15:20:48 yup with out that plugged in you get no deflection.
Posted by: olePigeon on 2015-06-09 10:00:53 That's what I thought. 🙂 Ran into the same problem myself a few days ago. I've been mix and matching analog boards and tubes recently to get a nice, working set.
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