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| IIc strange image |
Posted by: Lycus on 2022-07-17 17:10:03
I'd still replace it, it looks kinda funky still. |
Posted by: WillJac on 2022-07-17 17:21:17
Ok I will get my new chips Tuesday so I will remove it and put in a socket for now and wait for the new. I also get the new memory so will do the ls32 first and if need the memory after |
Posted by: Lycus on 2022-07-17 17:23:02
Well here's to hoping! |
Posted by: WillJac on 2022-07-17 17:26:55
Well here's to hoping! Thanks for all your input and guidance. This how i learn and will be able to pass it along to others. Will keep you posted. If you think anything else let me know. I am retired so I am always around. |
Posted by: Lycus on 2022-07-17 17:27:28
I'm a student so I'm always around. Have a great night! |
Posted by: WillJac on 2022-07-17 20:13:51
You think good be something with the TMG chip as I have no video7M output from the chip only place I see something missing. |
Posted by: WillJac on 2022-07-17 20:15:42
Sorry vid7m from pin 13 goes to the video chip after on pin 6. I have no signal at all on 13 or 6 but on other machine as soon as I turn on, I have signal wave. |
Posted by: Lycus on 2022-07-17 21:35:15
Trace that as well |
Posted by: WillJac on 2022-07-17 21:42:57
Can’t trace more. The signal originates from tmg chip goes to IPS then the video signal. It’s a timing clock signal so if that not there I do t think the video will come up good. |
Posted by: Lycus on 2022-07-17 21:45:47
Can’t trace more. The signal originates from tmg chip goes to IPS then the video signal. It’s a timing clock signal so if that not there I do t think the video will come up good. Let's see first if the 74LS fixes it, as broken RAM circuitry can cause cascading problems. |
Posted by: WillJac on 2022-07-19 17:40:51
I replaced the LS32 and 2 of the ram I found to be bad and now I get this. Any ideas? |
Posted by: Lycus on 2022-07-19 18:09:05
Look over the same points with an oscilloscope to see if they have improved |
Posted by: WillJac on 2022-07-19 20:21:08
Look over the same points with an oscilloscope to see if they have improved Some have. The LS32 for sure. Memory also but still issues. |
Posted by: Lycus on 2022-07-19 21:45:13
Hmm, can I see them probed again |
Posted by: WillJac on 2022-07-21 11:31:51
Ok let me get the readings and send them. So far what I am finding is EN80 is not enabled coming from MMU and also going to that LS32. |
Posted by: WillJac on 2022-07-21 19:48:39
I am going to park this for a few days work on some other stuff. My mind is fried about this logic board. I have a plus, Mac II and SE to work on. |
Posted by: Lycus on 2022-07-21 20:07:21
Take a break then |
Posted by: WillJac on 2022-07-22 08:56:47
Take a break then I send by email let me know if you get it. It’s part of a manual maybe you have that original manual can do a better scan. I am sure the community would value that. |
Posted by: WillJac on 2022-07-22 10:24:30
I send by email let me know if you get it. It’s part of a manual maybe you have that original manual can do a better scan. I am sure the community would value that. Wrong thread sorry about that. |
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