MindWalker
Well-known member
Here are two things I was playing with on my Mac 512Ke today 
First is a 3D-printed "battery replacement" for the early Macs. It uses three LR44 batteries in series (counting up to the 4,5v as the original) and mounts in place of the original battery. Much cheaper than buying one of those Exell A21PX (yes, still available). The STL-file is now available in Thingiverse: https://www.thingiverse.com/thing:4558846. You need to add a piece of wire and some sort of a battery contact on the negative end. Downside of this solution is that the capacity is only about half of the original battery (330 vs. 600mAh). But as a temporary measure it should work fine, and perhaps the LR44s are not as prone to leak and cause havoc as those big batteries. (I did think about having the batteries not touching either terminals of the Mac to further make sure leakage wouldn't get there, but as I don't have any good battery contacts to use, I went with this way: the top of the battery makes for the other contact and the other is wired over).
Here is the adapter next to an original (removed) battery:
And here is how it looks:
Second is a serial cable adapter. This is mostly just a heads-up, I tried to google if this really worked, but I couldn't find a definite answer. Yes it does!
The early Macs have 9-pin D-connector, unlike the later Macs that use a mini-din 8-pin connector. Most of the easily availabe serial cables (and PhoneNet adapters!) use the later connector. The early ones do exist, but are hard to come by. With this adapter, I was able to use LocalTalk over a mini-din 8-pin serial cable and access files my Performa, nice! The PhoneNet adapters should work too (only stuff that needs both the HSKi and HSKo handshake lines might not, as the D9 only has HSKi available). I had a peek inside one of my PhoneNet adapters and that was not wired to those pins at all so I'd guess they will work too. You need the AppleShare File Server 2.01 with the "AS201 WS 512Ke.image" to install the additional pieces (AppleTalk addin, plus a System update, after install I am now at Finder 6.1 and System 3.4, this is on a Mac 512Ke).
It's just a 6-wire cable with a male D9 on one end and a 8-pin mini din female on the other. Those mini-din connectors are a pain to solder, but yeah, doable if you go slowly. I'll clean up my notes and post the wiring here tomorrow. It just adapts the signals from the different connector to the other, no need to add anything or swap pins.
First is a 3D-printed "battery replacement" for the early Macs. It uses three LR44 batteries in series (counting up to the 4,5v as the original) and mounts in place of the original battery. Much cheaper than buying one of those Exell A21PX (yes, still available). The STL-file is now available in Thingiverse: https://www.thingiverse.com/thing:4558846. You need to add a piece of wire and some sort of a battery contact on the negative end. Downside of this solution is that the capacity is only about half of the original battery (330 vs. 600mAh). But as a temporary measure it should work fine, and perhaps the LR44s are not as prone to leak and cause havoc as those big batteries. (I did think about having the batteries not touching either terminals of the Mac to further make sure leakage wouldn't get there, but as I don't have any good battery contacts to use, I went with this way: the top of the battery makes for the other contact and the other is wired over).
Here is the adapter next to an original (removed) battery:
And here is how it looks:
Second is a serial cable adapter. This is mostly just a heads-up, I tried to google if this really worked, but I couldn't find a definite answer. Yes it does!
The early Macs have 9-pin D-connector, unlike the later Macs that use a mini-din 8-pin connector. Most of the easily availabe serial cables (and PhoneNet adapters!) use the later connector. The early ones do exist, but are hard to come by. With this adapter, I was able to use LocalTalk over a mini-din 8-pin serial cable and access files my Performa, nice! The PhoneNet adapters should work too (only stuff that needs both the HSKi and HSKo handshake lines might not, as the D9 only has HSKi available). I had a peek inside one of my PhoneNet adapters and that was not wired to those pins at all so I'd guess they will work too. You need the AppleShare File Server 2.01 with the "AS201 WS 512Ke.image" to install the additional pieces (AppleTalk addin, plus a System update, after install I am now at Finder 6.1 and System 3.4, this is on a Mac 512Ke).
It's just a 6-wire cable with a male D9 on one end and a 8-pin mini din female on the other. Those mini-din connectors are a pain to solder, but yeah, doable if you go slowly. I'll clean up my notes and post the wiring here tomorrow. It just adapts the signals from the different connector to the other, no need to add anything or swap pins.
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