3.2 DME rework - upgrade to 28pin socket

[ischmitz]

I just wanted to share a couple of iPhone shots showing the correct way to rework the DME PCB. This unit needed a 28pin socket upgrade amongst other things. While some simply add the four missing pins and call it a day I don't like that approach. To do this correctly I de-solder and remove the old socket and clean up real good:



Then I install a new high-quality 28-pin socket and solder it in place properly. The key to good soldering is cleanliness, the right solder and good temperature. Top row done:



and the finished product:



Ingo

[kidrock]

that is very nice work, very clean.

[McLaren-TAG]

Originally Posted by ischmitz

The key to good soldering is cleanliness, the right solder and good temperature.

Well that and a good PACE desoldering rework station with vacuum control right on the hand piece.

[ischmitz]

I wish I had a de-soldering station. Somehow I never could bring myself to justify one or a hot-air rework station either. This was all done the good old-fashioned way with a soldering iron.

The hot-air station might make sense at some point when it comes to the SMD D-PAK devices with large cooling areas soldered to the PCB.

Ingo

[GaryR]

Nice job Ingo! Considering it's my DME i'm very pleased...

[david.avrahami@]

NICE JOB....but why converting it in the first place? any advantage?

[MotoSook]

Nice work Ingo. I have forgotten how handy you are with these things...I'll keep in mind for future work

[dshepp806]

Nice work, indeed. Good temp,..and clean!

BEST!

Doyle

[ischmitz]

Originally Posted by david.avrahami@

NICE JOB....but why converting it in the first place? any advantage?

The 28-pin socket can take the 27C64 (8 kbyte) and larger EPROMs all the way up to the 27c512 64k version. That way you can run the latest code from the "89 U.S. or ROW. In general I would always want to run the '89 code if I had a choice. There are several reasons for that:

- It probably has the most sophisticated part throttle maps and software - that makes for better drivability
- When you plan to get a custom chip for the DME the tuner most likely wants to work off the later code base
- The only EPROMs you can purchase today is the 28pin 27C512. If you buy a smaller 24pin EPROM its either NOS (new old stock) or used.

This DME will get a custom-tuned chip later. Depending on what the tuner works on I would always want to start with the latest base maps. Some only work on the WOT maps from what I understand.

Regards,
Ingo

[Tippy]

Nice wetting Ingo.