Help with SP-12 - mainboard related.

[12bit]

Hi Guys.

I recently noticed some strange behaviour with my SP-12 - and I measured the voltage on the battery - it was dead.

I exchanged it with a new 3V Lithium battery but something must have gone wrong because my SP does not boot anymore. Nothing in the display, no lights, no nothing :-(.

I examined my soldering underneath the mainboard of the SP - and maybe some of my 'work' has cut some traces/melted some traces on the board.

But I am not sure as I can't tell for sure. I don't seem to be able to tell from the Service Manual either (I am no great tech)

I was wondering if anyone in here has a picture of a working mainboard from underneath the print (more precisely around the battery solders).

Please please please help. I miss her.

Kenneth Abildgaard

[rtech]

Hey Kenneth, Ive changed the battery and other components on Sp12 and 1200s, on these the traces are pretty big so check for continuity with a multimeter. if you find that there is a break in the trace, solder a jumper cable. Make sure that you didnt bend any capacitors they can be shorting out. On one that I did i had bent a capacitor by the OS EPROMs and it would not boot. After i straightened out and it was no longer shorting out, the SP12 booted properly.

  If you look some of the components are soldered on top of others they have plastic protectors over the exposed leads. These are the ones you should check.

rtech

 

[12bit]

Thanks rtech. I will look into your suggestions.

Best;

Kenneth

[rtech]

No problem. One more thing, when you soldered the battery leads make sure that you didnt put too much solder as one of the solder points has a trace real close by. Make sure that the battery lead is not shorting out with that trace. If I remember correctly this is on the solder point closer to the front of the SPs board.

[12bit]

I took a picture from underneath my SP12's Mainboard.
I really REALLY think I messed it up - but have a look.

If ANYONE plan to exchange their battery or have their SP12 taken apart PLEASE take a picture similar to mine (but sharper please :-).

I would really like to see how it's supposed to look - and to see what goes to what here :-(

HELP HELP HELP !!

KennethA

[sfbaytech]

That blob of solder on the right hand pin looks like it is shorting the two tracks together.

[rtech]

kenneth, yeah it looks like there is a short like sfbaytech said. The other thing i noticed is that the trace by the battery pin on the left looks like its been cut, but its hard to tell as there are black burn marks around the pins. Us alcohol with a toothbrush and clean it so you can see it clearly.


rtech