Logic Board - Macintosh SE Reloaded

[Kai Robinson]

So many classic macs, starting with the SE, have died because of Apple's short sighted decision to add a battery to the board. This inevitably leaks and causes a horrific amount of damage. Luckily - most of the custom chips survive even this, so I decided to make a near 1:1 reproduction of the board, using Sprint Layout v6.0

Project inspired by Rob 'Peepo' Taylors work on the A500++ and the SixtyClone PCB's, which in turn were inspired by John 'Chucky' Hertell.

These boards aren't quite enough to build a new Macintosh SE from scratch (maybe one day, though!) - so you'll need to harvest a few parts from your donor board.

• SIMM Sockets - If you can get some from here: https://www.peconnectors.com/sockets-pga-cpu-and-memory/hws9229/ then do so!
  
  Re-using and cleaning up your old ones involves desoldering. These need a lot of heat as there are a lot of connections to the ground plane. Pre-heat the joints, maybe add a dab of proper Kester 63/37 eutectic LEADED solder (none of that RoHS crap), flood with flux.
  
  
• PDS Socket - Amphenol/AMP/AVX DIN-41612 3-row, 96-pin connector (Style-C) - Available new, but still worth reclaiming as sifting through the minute variations of parts is an arse...
  
  
• DB19 Connector - Almost NLA, only really available as NoS or Reclaimed. These are a bastard to get out cause the lugs are soldered. I found that pre-heating the joint first, filled with flux, then pressing hard into the pad with the desoldering gun, waiting til you see the solder go molten, you can often schlorp out the majority of the solder and then tidy up with wick afterwards.
  
  
• NoS ones available from https://www.exxoshost.co.uk/atari/store2/ - search for DB19F ASCI PCB RA POST
  
  
• Main 14-pin Molex - Molex P/N 39-28-1143 - Still available new - costs less than £2. Get a new one.
  
  
• Inductors - probably easy enough to get new ones, but ehhh, they don't really break, and they fit fine. Reuse the big ones - buy new small axial ones.
  
  
• Passives - REPLACE ALL - use high tolerance metal film resistors & nichicon or panasonic electrolytics. Maybe try and save the PLCC Socket if you can. remove it cleanly - sometimes the pins pull out but they can be put back in if you're careful.
  
  
• AM26LS30's - NLA, only available as NoS or Reclaimed
  
  
• AM26LS32's - Available new, but still worth reclaiming
  
  
• MC3488A - NLA - replace with Texas Instruments SN75150
  
  
• Rockwell 338-6523 - This is identical to the 65C22N VIA, still available new
  
  
• RTC Chip - Custom Chip - maybe possible to clone using pin-compatible ATTiny85
  
  
• ADB Chip - Apple branded PIC16CR54 - maybe possible to re-produce/clone
  
  
• GLU Chip - Apple branded HAL16L8 - this has been reverse engineered for both ATF16V8 and discrete logic!
  
  
• BBU Chip - Custom Chip
  
  
• NCR5830/AM58C30 SCSI Chip - NLA, only available as NoS or Reclaimed from UTSource
  
  
• IWM/SWIM Floppy Chip - Custom Chip - available NoS from UTSource
  
  
• Hi & Lo ROM Chips - Toshiba TC531000CP MASK ROM's - Reclaim & reuse, but these are the same pinout as 27C512, but adds A16 in place of VPP pin - you can use 27C010's on an adapter - doug brown made a similar setup with a built in ROM disk for the Mac Plus.
  
  
• 74LS245 - Available new, but still worth reclaiming - replace with CY74FCT245ATPC or CD74FCT245E
  
  
• 74F257 - Available new, but still worth reclaiming - replace with CD74ACT257E

Project is available on GitHub here: https://github.com/kr239/Macintosh-SE-Reloaded

 

[JDW]

@Kai Robinson, you are in fact The Real Santa...

This is going to be an incredible build, folks!

 

[JDW]

Got a battery bombed SE? Want to have fun assembling a brand new Mac motherboard from scratch? Kai Robinson reverse-engineered the solution. My Part I video shows you how to get started.

 

[alex_santos]

Hello Kai. Does the board come only in red? I am trying to find the board in black. Could you advise please?

 

[JDW]

Hello Kai. Does the board come only in red? I am trying to find the board in black. Could you advise please?

Alex, it comes in colors other than Red only when you use the Gerber files on Kai's Github page to have your own board made at a PCB maker like PCBWay, JLCPCB, etc. I will eventually mention that in one of my videos in this series.

 

[alex_santos]

Yes Kai replied on Discord similarly. I have never interacted with either of those companies. If you do know something about the process (what is involved) and perhaps have a ball park figure on the costs involved, please do include it in the video itself or as a link comment. Thank you for considering the additional information as part of your video James!

 

[JDW]

If you do know something about the process (what is involved) and perhaps have a ball park figure on the costs involved, please do include it in the video itself or as a link comment. Thank you for considering the additional information as part of your video James!

Alex, the single biggest problem I have in recommending JLCPCB, PCBWay, etc. is the fact they all require you to build 5pcs minimum of any PCB. So while the cost of one matte black SE Reloaded PCB (with Gold ENIG pads) at PCBWay, for example, is reasonable, what individual user needs 5pcs? Answer: Nobody except an authorized seller, but currently Kai only authorizes MacEffects (and one other party who doesn't have the item on their website).

Based on the "instant quotes" I get by dropping Gerber files into JLCPCB and PCBWay, I see JLCPCB is cheaper than PCBWay. But even at that cheaper price (even at 1/2 or 1/3 the PCBWay price), the total cost of 5 SE Reloaded boards with shipping is more than any hobbyist would want to pay, unless they are the very rare person seeking to make 5 boards for their own personal use.

I actually wanted to do a video on PCBWay (since they privately approached me via email), but I'm not sure how to recommend this service in light of what I've just said.

Pretty much all of us would love to find Gerbers online and then have only 1pc created at a PCB maker so we could then do a build. But do we really need 5pcs? Okay, maybe small and cheap PCBs like BlueSCSI if you've got a lot of vintage Macs. But large and comparatively expensive PCBs like SE Reloaded, especially with options like the lovely matte black and gold ENIG pads? No, I'm not seeing individual hobbyists flock to PCB makers in droves to buy a min. of 5pcs of that board. It's just no going to happen, except in maybe 2 or 3 super rare cases.

Now if anyone reading this has any suggestions that I've not considered please share! In other words, how do we solve the 5pc min. order delimma?

For now, the old "solution" seems to be to buy the red board from MacEffects, which is great if you like red. But the only way to get other colors is to order 5pcs yourself, or hope MacEffects or Kai or another authorized seller offers them in other colors.

Thanks.

 

[Kai Robinson]

As mentioned @JDW i'll be selling them direct in the UK, in matte black, with ENIG gold, but i can't afford to do a run right now - i do have 38 of the blue/gold ones in stock, for anyone in the UK that wants one (may do EU shipping depending on customs).

 

[JDW]

As mentioned @JDW i'll be selling them direct in the UK, in matte black, with ENIG gold, but i can't afford to do a run right now - i do have 38 of the blue/gold ones in stock, for anyone in the UK that wants one (may do EU shipping depending on customs).

I’ll be sure to present that info in my Part II video, Kai. Thank you!

 

[alex_santos]

Thank you both for your replies. I understand the delay.

For those who love blue/gold red/gold boards you have options - today. I do believe these colored boards, the only ones currently, as of this writing, would really shine inside a transparent case.

I can wait when for the next run Kai. Please let us know when and how we can pay. I have my debit card on standby

 

[Kai Robinson]

It won't be until i run out of the blue/gold ones

 

[JDW]

The SE Reloaded build continues in my Part II video...

Many thanks to Kai, who was very helpful during the making of both videos to date. Stay tuned for Part III!

 

[alex_santos]

The SE Reloaded build continues in my Part II video...

Many thanks to Kai, who was very helpful during the making of both videos to date. Stay tuned for Part III!

Thank you James for the video and obviously not just this one. Keep up the great work!

 

[Paolo B]

This project is really fascinating, congratulations.
And I truly appreciate the videos, they are both insightful and entertaining, thanks @JDW !
Fortunately, though, I don’t have a busted plain SE to rebuild.

However, I have an SE/30 logic board which – unfortunately - needs (as minimum) the external floppy Bourns filter to be replaced.

So, I was very carefully watching the video for understanding about any caveat.

Considering the high cost of the Bourns filters and the fact that de-soldering is always a huge pain with the risk of damaging either the chips or the motherboard, I was considering pulling all the 3 filters (likely: clipping them) and replacing them with socketed chips.

However, I could see from the Part 2 video that it’s indicated not to socket the filters.

What’s the reason for that? Is it just not possible (packaging space), unnecessary or is it indeed detrimental?

 

[Kai Robinson]

@Paolo B generally they don't tend to fail - it's also a part that's been replicated, so you don't need to worry about them not being available anymore either. Plus, general things such as trace lengths for signals, interference etc. There's a time and place for sockets

 

[retr01]

The SE Reloaded build continues in my Part II video...

Many thanks to Kai, who was very helpful during the making of both videos to date. Stay tuned for Part III!

Hey @JDW, is the polo shirt that you have on in that video something you custom-made? Looks cool!

 

[JDW]

Hey @JDW, is the polo shirt that you have on in that video something you custom-made? Looks cool!

You have Motherboard Creator & Polo Shirt Maker Extraordinaire, @Kai Robinson , to thank for that. He very graciously sent it to me. I like it!

 

[retr01]

You have Motherboard Creator & Polo Shirt Maker Extraordinaire, @Kai Robinson , to thank for that. He very graciously sent it to me. I like it!

Now we need "SE/30 Tinkering Team" polo shirts...

 

[JDW]

Now we need "SE/30 Tinkering Team" polo shirts...

@Kai Robinson is on the TD board, and we know he has Polo Shirt design skills. Not sure if he has the time or the desire, but if he does, that would be yet another cool feather in his cap!

Hint, Hint, Kai!

 

[Kai Robinson]

Haha - well, i don't mind putting together a group buy for T-Shirts/Polo Shirts - but perhaps @Mac84 would like to have a crack at it, too