Mac SE/30, Death Chimes and Horizontal Stripes

[NZ_KGB]

Recently acquired an SE/30, originally it had just a vertical line on the screen and no chime.

I've re-capped the digital and analog boards. Washed the digital board with denatured alcohol.

Now it just shows the stripped screen and death chimes, same as here:





I'm fairly new to these kinds of repairs and working with classic Macs so apologies if I've missed anything obvious.

What I've tested:

Tested capacitors are soldered OK following: https://68kmla.org/forums/uploads/monthly_2020_05/post-2686-0-63668700-1502804268.png.9ee7e68f85620e11a65918b16be49067.png

Voltage on Floppy Port pins is OK +12v on 7/8, +5v on 6

Swapped around the ram, various configurations and simms, seems with 4 simms it doesn't chime on first boot or reset button only when pressing the interrupt button?

The ROM is held firmly in place, have tried holding it on boot.

Traces appear OK and have tested A2-A22 to the 74F258 chips OK

Board:





Broke C13 ground pad , soldered a wire to ground from it and tested OK:



Any suggestions on what to try next?

Replace the 74F258 chips?

Unfortunately I don't have a working SE/30 or ROM to test with

 

[Daniël]

If you install four SIMMs, are all four the same capacity? You must use the same capacity of SIMMs in each bank, of which the SE/30 has two (four SIMMs = one bank). I'm pretty sure it won't run with half a bank of memory. If you install one bank of memory, Bank A must be filled first, which is the four SIMM slots nearest to the edge of the board. 

While the stripes can indicate a problem with the video circuitry, I'd really implore you to try troubleshooting RAM first. I have seen people get Simasimac situations with bad RAM or incorrectly installed RAM. Do you have a way to verify the SIMMs you currently have are working? Or do you have another Mac with four 30 pin SIMMs you could borrow from?

 

[bibilit]

I agree a 100%. 

Your picture is showing a half B bank filled, won’t work. 

A bank first with same type and capacity. 

The board is chiming at some point, so probably on the right track with memory issue. 

 

[joshc]

Side note: I'm surprised that board even fits in the chassis with electrolytics that tall in replacement of the original axials.

Also, be careful with leaded electrolytics sitting on the solder pads like that, if you knock them accidently it will probably pull the pads off the board with them.

I hope you get it booting happily with the correct memory installed.

 

[NZ_KGB]

Thanks for the replies, I didn't know about the whole bank needing same size RAM and needing to be full, will try that.

I only have a working Mac Classic II, would that work testing 2 simms at a time in it?

With the replacement caps for the axial ones, the picture makes them look a lot taller than they are. And yes I have managed to break C13 that way already.

 

[NZ_KGB]

Success, after cleaning the contacts and swapping the RAM around I got the original 4 to work.



Thanks again!

 

[NZ_KGB]

I got it up and running, but now it freezes after some time and won't boot again for a while.

Have swapped the ram around again a few times with known working simms,

Symptoms are a bit random, sometime it death chimes on cold boot but OK when reset, other times boots OK, it always freezes after some time.

I don't think all the ram I have is bad, it's working in a Classic ii.

Any pointers what to try next?

Bad cap job?

 

[NZ_KGB]

Running better now with 8 simms, after abut an hour got these messages: