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| Is this classic an analog adjustment |
Posted by: imactheknife on 2022-09-17 17:47:51
I recapped a classic analog board not knowing if it worked. I have gotten it to turn on and boot. I am getting like shadow lines across screen from icons or open windows. Is this an adjustment issue or something with cap job? |
Posted by: imactheknife on 2022-09-17 17:50:12
Classic analog |
Posted by: joshc on 2022-09-17 19:05:34
I can’t really see what you mean on that photo, can you take a few more or maybe a video? |
Posted by: Byrd on 2022-09-17 21:04:36
Adjust focus, brightness cut off - see Classic service manual for pot adjustment at the back of the unit |
Posted by: imactheknife on 2022-09-18 07:53:10
Adjust focus, brightness cut off - see Classic service manual for pot adjustment at the back of the unit Ok, will do. |
Posted by: imactheknife on 2022-09-18 09:36:57
Looks worse today lol.. really hate analog boards
tried adjusting stuff as per service manual, unfortunately nothing improved anything. |
Posted by: imactheknife on 2022-09-18 17:46:03
The brightness pot seemed to do nothing. Focus looked more like brightness adjustment then focus |
Posted by: joshc on 2022-09-18 19:16:53
What tool are you adjusting the pot with? A lot of things will fit but not actually turn the pot. |
Posted by: imactheknife on 2022-09-19 15:17:50
What tool are you adjusting the pot with? A lot of things will fit but not actually turn the pot. Have a hex key that fits i am sure lol.. i feel feel it reach its end on either side when turning it. Pots go bad too no?? |
Posted by: Byrd on 2022-09-19 19:53:14
Yes they can but note you need to use a non-conductive tool to adjust the pot; I find a wooden skewer slightly filed/copped on the end works well. |
Posted by: chiptripper on 2022-09-22 10:02:32
What voltages are you getting?
I often have trouble with PP1 on these boards, a good clean with IPA and a turn back and forth goes a long way. Make sure to get voltage back where it needs to be and use non-conductive tools. |
Posted by: imactheknife on 2022-09-22 15:59:06
Yes they can but note you need to use a non-conductive tool to adjust the pot; I find a wooden skewer slightly filed/copped on the end works well. Good idea🙂 will try |
Posted by: imactheknife on 2022-09-22 16:00:02
What voltages are you getting?
I often have trouble with PP1 on these boards, a good clean with IPA and a turn back and forth goes a long way. Make sure to get voltage back where it needs to be and use non-conductive tools. Was getting proper voltages but will check again |
Posted by: chiptripper on 2022-09-22 19:43:50
Got a closer look at your pics, looks like horizontal smearing. I'm not a CRT expert by any stretch but I understand it can be caused by interference, poor connections, bad ground, or a failing CRT. Could also happen if you used high ESR caps, but I doubt that's the prob.
Do you have a working Classic or Classic II? Process of elimination? |
Posted by: imactheknife on 2022-09-22 20:08:18
Got a closer look at your pics, looks like horizontal smearing. I'm not a CRT expert by any stretch but I understand it can be caused by interference, poor connections, bad ground, or a failing CRT. Could also happen if you used high ESR caps, but I doubt that's the prob.
Do you have a working Classic or Classic II? Process of elimination? I have a classic and classic ii recapped boards. Both result in same thing. My other analog board has issues too. Will take apart and snap a few pics of caps. They could be an issue? I double checked my caps so none were reversed. Made sure no shorts that i could see. I didn’t know the state of either analog boards as i recapped analog first while trying to figure out logic board issues. Then other classic and classic ii’s came into my life with working analog boards so i could test my previous logic boards. Once i knew i had a good working logic board i went back to the original analog boards i recapped and found out they don’t want to play lol.. well, they do, just need to figure out the issue… appreciate your input |
Posted by: chiptripper on 2022-09-22 23:54:54
Caps might cause an issue if you somehow chose wildly out of spec (high impedence / high ESR) for the output section of the analog board, but I think that's really unlikely because even general purpose caps should work OK. More likely it's a bad CRT, that's my guess anyway. But the only way to tell is by swapping components to isolate the flaw. (The Classic II AB will work on the Classic, but not the other way around AFAIK.) |
Posted by: imactheknife on 2022-09-23 06:30:12
Oh wow, didnt know that classic AB wont work with classic ii, thanks for that!. Will see what happens this weekend. Havent been able to get back to them as other projects have taken over lol |
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