Logic Board - Macintosh SE Reloaded

[JDW]

@iPhil64
Very nice gold-plated sockets!


Did you buy those individually from Mouser?
If you bought them in a kit, I could add a link to that in my BOM as an alternative to the kit I link to right now.

I bought the double-wipe socket kit because Kai told me double-wipe makes getting the chips out a bit easier. The chips I desoldered from the stock SE board fit OK in my double-wipe sockets, but the legs are shorter on the desoldered ICs than on the new ICs, so desoldered ICs might be more secure in the the premium sockets you are using. And of course, the gold looks prettier too!

 

[iPhil64]

These ones were purchased from DigiKey. The Amazon kit was not available for me in France which is why I purchased them from here (and I mad a mistake on the U4E one... not the right pin count !). They were definitely not the cheapest. They are certainly available on Mouser.

Kai is right, double-wipe is easier to remove. Now at the same time, the contact is definitely to as good. I just acquired an AppleSqueezer GS for my Apple 2GS, and Apple did use double-wipe sockets back in the days. The accelerator card would simply not stay in the socket. Once changed, the fit and contact are perfect, and yes.... much harder to remove.

As for the gold, yes, they look gorgeous. Now, they are not all the same (you can see on this picture "partial" and "full" gold, then classic tin finish.... too bad. Maybe when Kai bring out a new batch of Black boards and I do my third one ? ahah.....

 

[JDW]

So far, none of the chips (not even the short-legged chips I desoldered from the stock SE motherboard) have accidentally popped out of their double-wipe sockets. But I would say that if someone building SE Reloaded really doesn't have any intention of removing the chips from the sockets, they should buy the same sockets you have, because I think your sockets will hold the chips in there much more securely, which is important for any chips you desolder, because they have short legs. The new chips have long legs which sink deep into the double-wipe sockets and probably won't ever come out, even if your transport your SE a lot.

 

[iPhil64]

Well, yes, in case of single chips, they should not fall. The AppleSqueezer GS (off-topic, don't ban me ! lol) is a bigger and heavier beast that has to stick on a 40-pin socket.

See below. The original Apple sockets are not only double-wipe, they also have an external rail that prevent proper insertion of the modern round pins.

Now as far as SE Reloaded, since the chips were meant to go in such sockets, this is less an issue of course.

 

[iPhil64]

Damn !
I did not pay attention to my DigiKey order, and I just received the gold versions (which had a small delay) of the sockets that are not gold on the pictures...
Desolder - resolver ? .....

I also received the 33 µH coils, they will fit nicely I guess, as well as the new old stock Bourns filters.

 

[iPhil64]

So...
- The Bourns filters from DigiKey are really genuine parts from 2017. No issue at all (of course I would have preferred a yellow version which look more exotic, but hey... that's life).
- As for the filters, they do fit quite nicely on the red motherboard (see below), but the leads can not go through the blue PCB holes, which are so slightly smaller.

 

[JDW]

Damn !
I did not pay attention to my DigiKey order, and I just received the gold versions (which had a small delay) of the sockets that are not gold on the pictures...
Desolder - resolver ? .....

"delay"?

You received gold-plated sockets, but they were not gold on the DigiKey product photo pages? That's a good thing, right?

 

[iPhil64]

"delay"?

You received gold-plated sockets, but they were not gold on the DigiKey product photo pages? That's a good thing, right?

I had ordered two versions as I need some to fix the 2GS. They sent them in two batches. I first received the ones with less gold on the 40-pin sockets. They did send me what I had ordered.
Sorry if I wasn't clear... don't get much sleep with the heat and all the soldering

 

[tmtrains]

So...
- The Bourns filters from DigiKey are really genuine parts from 2017. No issue at all (of course I would have preferred a yellow version which look more exotic, but hey... that's life).
- As for the filters, they do fit quite nicely on the red motherboard (see below), but the leads can not go through the blue PCB holes, which are so slightly smaller.

View attachment 6765

Do you have a part number for the filters? I probably need to replace at least one of the ones I took off of the old board.

 

[iPhil64]

Do you have a part number for the filters? I probably need to replace at least one of the ones I took off of the old board.

Sure, this is the one I purchased : https://www.digikey.fr/en/products/detail/bourns-inc/2100LL-330-H-RC/725953

Again, be careful, the leads are thick, and did not go through the Blue reloaded board, only the red one. Now, I think it will work with a bit of sanding, I just did not have the time yet.

I looked at other parts they have, we could have thinner leads with other coils, but they would have a vertical mount, and I guess that would not fit into an SE case because of the height.

 

[Kai Robinson]

That's odd as i didn't change the hole sizes for the maceffects board gerbers - must just have been a manufacturing thing with the blue ones!

 

[iPhil64]

That's odd as i didn't change the hole sizes for the maceffects board gerbers - must just have been a manufacturing thing with the blue ones!

The difference is really really subtle. Could be an effect of the plating ?

On the blue one, I measure 0.88 mm vs 0.91 mm on the red version , we are talking 3 µm difference ! (assuming I measure properly, as it is not easy).

The coils data sheet from Bourns (https://www.bourns.com/docs/Product-Datasheets/2100ll_series.pdf) says leads should be 0.042 inch, which is 1.06 mm. I measure mine at 0.90 mm, so I may be lucky.

This also explains, in part the difference of soldering flow.

Never mind.

@JDW I now received all parts from UTSource, including the all the ones that were on inquiry, including the Bourns filters in... yellow... not sure if I will change them on the boards or not ... ahahah.

 

[iPhil64]

By the way, I had a first look at all UTSource chips. The apparent quality seems pretty good, and there is plenty of new old stock. For the ones that are used parts, the quality of desoldering seems decent as well.

They're not cheap, but an excellent source. They shipped in 5 days, and it even arrived 4 days earlier than planned.

If you look at the list, only 3 used parts : SND 3440042B (funny, the Apple-A version is a new part !), SCC and yellow Bourns filters. Everything else is new old stock. Amazing...

344-0062-A(new)
3430045A(new)
3440042B(used)
AM85C30-8PC(used)
4120R-601-250/201(used)
NCR53C80-40(new)
MC68000P8(new)
AM26LS32PC(new)
AM26LS30PC(new)

 

[iPhil64]

Now starting a batch of programmer's buttons holders. I'm testing 3 different models from the link @JDW shared previously. 4 of each, should be done in about 1 hour, will keep you updated.

 

[iPhil64]

I think I will go for the top right one. Any thought ?
BTW, if anyone wants me to print such things do not hesitate, I can do other Colors. I would only charge for shipping, the cost of labor and material is negligeable. Of course donations will always be accepted !

 

[JDW]

I think I will go for the top right one. Any thought ?
BTW, if anyone wants me to print such things do not hesitate, I can do other Colors. I would only charge for shipping, the cost of labor and material is negligeable. Of course donations will always be accepted !

View attachment 6797

Be sure to solder in those switches and then press on them to see if there is any movement of your 3D printed switch mount. On a stock SE motherboard, there is almost no movement when pressed. When I first soldered my stock switch mounts (removed from a bad stock SE motherboard) into SE Reloaded, one of the switch mounts moved when I pressed it. I pressed down on it and reapplied the solder to fix the problem.

 

[iPhil64]

Be sure to solder in those switches and then press on them to see if there is any movement of your 3D printed switch mount. On a stock SE motherboard, there is almost no movement when pressed. When I first soldered my stock switch mounts (removed from a bad stock SE motherboard) into SE Reloaded, one of the switch mounts moved when I pressed it. I pressed down on it and reapplied the solder to fix the problem.

Good point, thanks for bringing my attention on this !

Also you can see on the three models I tried that I sliced them a bit too high, with no support feet to go in the PCB holes.
Some models did have the feet but I went through Cura too fast at lunch time and did not pay attention in fact.
From the discussions on 68kmla, it seems that does not cause a problem, but I want to try first.

 

[JDW]

Good point, thanks for bringing my attention on this !

Also you can see on the three models I tried that I sliced them a bit too high, with no support feet to go in the PCB holes.
Some models did have the feet but I went through Cura too fast at lunch time and did not pay attention in fact.
From the discussions on 68kmla, it seems that does not cause a problem, but I want to try first.

The "feet" you mention are the two little posts that are at the very bottom of the switch holder, and they sink into the PCB to keep the switch holder firm.

Those little "feet" do matter, in my experience. Without them, all the pressure of your finger (when pushing the bottom) will be applied to the two metal legs of the switch, possibly weakening the solder joints over time. The presence of the two little plastic feet ease the stress on the soldered legs of the switch.

 

[iPhil64]

The "feet" you mention are the two little posts that are at the very bottom of the switch holder, and they sink into the PCB to keep the switch holder firm.

View attachment 6798

Those little "feet" do matter, in my experience. Without them, all the pressure of your finger (when pushing the bottom) will be applied to the two metal legs of the switch, possibly weakening the solder joints over time. The presence of the two little plastic feet ease the stress on the soldered legs of the switch.

OK.
I will reslice the model with the posts (thank you for the correct term !).

And stop hammering the buttons ! Be gentle....

 

[alxlab]

I'll make a proper post and github repot for the interrupt/reset switch back but until then here's the latest models. I updated the height slightly.

I've included the 10x version of the model if someone wants to have it printed at JLCPCB. The best results was with with the MJF printing and PA12 material.

The pictures are of v1.0 printed at JLCPCB.






License for the models are CC-BY-SA