SE/30 was working one moment, then it wasn't
- Thread starter JeffC
- Start date
Hi All,
In a tragicomic twist, while trying to fix the unfortunate damage I caused to the logic board of my beloved SE/30 as I inadvertently shorted the external floppy, I decided to run some basic maintenance on the analog board, too.
In particular, I decided to replace the infamous P1 connector, as severely baked at green line pin. Apparently, an easy task.
But when I put everything back together, to my utter dismay the display lasted just a couple of minutes and then, all of a sudden, collapsed to an horizontal line. Vertical sweep gone.
Since according to Larry Pina, it might indeed be an issue with cracked joint on pin 4 of connector P1, I re-flowed it again, maybe it was something not visible. Something has changed, now the screen looks half collapsed: the top half is visible (albeit “squashed”), the bottom half is dark.
Definitely vertical deflection is gone.
Again, according to Larry Pina, suspect is now TDA1170…
Now, before starting the painful process of trial and error for identifying the culprit, I’d like to know if you have any suggestion on what to check first.
Thanks in advance for your support.
In a tragicomic twist, while trying to fix the unfortunate damage I caused to the logic board of my beloved SE/30 as I inadvertently shorted the external floppy, I decided to run some basic maintenance on the analog board, too.
In particular, I decided to replace the infamous P1 connector, as severely baked at green line pin. Apparently, an easy task.
But when I put everything back together, to my utter dismay the display lasted just a couple of minutes and then, all of a sudden, collapsed to an horizontal line. Vertical sweep gone.
Since according to Larry Pina, it might indeed be an issue with cracked joint on pin 4 of connector P1, I re-flowed it again, maybe it was something not visible. Something has changed, now the screen looks half collapsed: the top half is visible (albeit “squashed”), the bottom half is dark.
Definitely vertical deflection is gone.
Again, according to Larry Pina, suspect is now TDA1170…
Now, before starting the painful process of trial and error for identifying the culprit, I’d like to know if you have any suggestion on what to check first.
Thanks in advance for your support.
This could be a silly question, but... are you sure is the analog board?
One of the chips UD8, UE8, UF8 (I don't remember which, I don't have the schematics handy) deals with the vertical synch and these chips trend to go bad with the cap juice... I had the horizontal line issue on mine and it was solved changing the IC.
One of the chips UD8, UE8, UF8 (I don't remember which, I don't have the schematics handy) deals with the vertical synch and these chips trend to go bad with the cap juice... I had the horizontal line issue on mine and it was solved changing the IC.
Interesting, thanks!
No, I am not sure, not at all. Frankly, the whole analog board looks in pristine conditions.
I will try and visually assess that area, maybe there’s something wrong there...
Mine is pristine, yet it had cracked solder joints. See the earlier post in this thread on the first page that discussed cracked solder joints with a picture on the back of the board showing cracked solder joints.
Helo gang! Just joined last week, this is my FIRST POST!!
For the past 4-5 weeks I've been playing with an SE Superdrive I've had for a while. I'm having fun tinkering with it.
I decided I NEEDED an SE/30 as well! lol, so I got one from eBay that was not working but looked clean. it arrived last evening.
I powered it up with the SAME symptoms mentioned on this thread, no chime, that odd pattern on screen, so I read all posts.
I swapped power supplies with a known good one (Astecs), no change.
Reseated ROM & disconnected int SCSI & floppy: No change.
Reseated RAM: BINGO!!! got "floppy w/ ?" PROGRESS!!!!
internal HDD seems dead,. but my 20SC booted it fine into Sys 7.0
Still no chime though. In control panels, I played with volume and different sounds-no audio. Maybe a bad speaker? It is connected. I have mother board & PSU outside of the case with extension cables-LOVE that tip!
So, I wanted to second the motion of trying the ROM & RAM chips first-it may be it!
I will recap BOTH Macs in the future. I'll be ordering MANY of JDW's Mouser carts!
For the past 4-5 weeks I've been playing with an SE Superdrive I've had for a while. I'm having fun tinkering with it.
I decided I NEEDED an SE/30 as well! lol, so I got one from eBay that was not working but looked clean. it arrived last evening.
I powered it up with the SAME symptoms mentioned on this thread, no chime, that odd pattern on screen, so I read all posts.
I swapped power supplies with a known good one (Astecs), no change.
Reseated ROM & disconnected int SCSI & floppy: No change.
Reseated RAM: BINGO!!! got "floppy w/ ?" PROGRESS!!!!
internal HDD seems dead,. but my 20SC booted it fine into Sys 7.0
Still no chime though. In control panels, I played with volume and different sounds-no audio. Maybe a bad speaker? It is connected. I have mother board & PSU outside of the case with extension cables-LOVE that tip!
So, I wanted to second the motion of trying the ROM & RAM chips first-it may be it!
I will recap BOTH Macs in the future. I'll be ordering MANY of JDW's Mouser carts!
The pattern is due to the system not clearing video ram, not "weird" persay.
If you need someone to recap the system, let me know. I will be at VCF East this weekend too.
Thank you-good to know re: what the pattern means. Where can I learn more about VCF East? What/where is that?