sf78 wrote:

Finally formatted a few Rainbow compatible disks and booted a DOS 2.1. Still need to see if I can get the HDD to function. Maybe next year...

dos.jpg

Slight screen rot on the corners there, but meh.

It is beautiful! What is this?

needs more skeletor

OldCat wrote:

sf78 wrote:

Finally formatted a few Rainbow compatible disks and booted a DOS 2.1. Still need to see if I can get the HDD to function. Maybe next year...

dos.jpg

Slight screen rot on the corners there, but meh.

It is beautiful! What is this?

DEC Rainbow.

Even by DEC standards a highly eccentric machine, with VT100-terminal, CP/M Z80 and DOS 8088 functionality in one - with unique dual 400kB SS/QD floppy drive. I lust after one of those drives, just for their looks. Which is good, because there's no sensible way of using them otherwise outside of a Rainbow 😉

Did a rebuild of my 486dx2-80. Were I moved it to another AT case. Finally I can begin the "486dx-33-Pure-ISA" build that have been sitting in a box, just waiting for it to be a complete machine. Hardest thing was to source AT cases these last couple of years.

First step was to solder in a new battery. I have begun using 3.6 volt rechargeable 2032 batteries, instead of them old barrel types. I cleaned up the board by removing old solder, cue tip and isopropyl alcohol and finally soldering in the new battery. When the build is done, I will make a post or log or something of this machine.

Looks pretty good, man.

bjwil1991 wrote:

Looks pretty good, man.

Thanks. 😀

It is not by any standard perfect. I was a bit sloppy when adding solder. It is however ok and useable.

brostenen wrote:

Did a rebuild of my 486dx2-80. Were I moved it to another AT case. Finally I can begin the "486dx-33-Pure-ISA" build that have been sitting in a box, just waiting for it to be a complete machine. Hardest thing was to source AT cases these last couple of years.

First step was to solder in a new battery. I have begun using 3.6 volt rechargeable 2032 batteries, instead of them old barrel types. I cleaned up the board by removing old solder, cue tip and isopropyl alcohol and finally soldering in the new battery. When the build is done, I will make a post or log or something of this machine.

I find it amazing how people take these very, very old pieces of tech and do electrical work like this on them to give them new life. Nice one brostenen. 😀

brostenen wrote:

bjwil1991 wrote:

Looks pretty good, man.

Thanks. 😀

It is not by any standard perfect. I was a bit sloppy when adding solder. It is however ok and useable.

I'm not good at soldering either, and one of the many projects was fixing a sound card that lost the volume potentiometer and replaced the jacks on the card itself as well since they were either going out, or losing channels. Jumpered some wires from one spot to the next appropriate spot, and that worked successfully.

Also replaced the jack on a set of JBL Platinum speakers as well since they were done for, and made an audio cable with a capacitor and resistor at the 4-pin connector for hooking it up to my Tandy 3-voice Compatible Sound Card, which'll either output to my sound card, or the speaker I have internally.

the_ultra_code wrote:

I find it amazing how people take these very, very old pieces of tech and do electrical work like this on them to give them new life. Nice one brostenen. 😀

Thanks. 😀
This is the third time that I have used this kind of battery instead of barrel battery on old AT boards. Never had any issue whatsoever regarding overheating and stuff. I find this solution a better one, compared to the normal non-rechargeable and diode approach. The rechargeable battery in this case, comes with legs and are ready to be soldered in.

How convenient. 😀
Also, you then don't have to worry about battery leakage either, if I'm correct.

the_ultra_code wrote:

How convenient. 😀
Also, you then don't have to worry about battery leakage either, if I'm correct.

Exactly. 😜

dionb wrote:

Even by DEC standards a highly eccentric machine, with VT100-terminal, CP/M Z80 and DOS 8088 functionality in one - with unique dual 400kB SS/QD floppy drive. I lust after one of those drives, just for their looks. Which is good, because there's no sensible way of using them otherwise outside of a Rainbow 😉

Yes, all in all quite a mad design this. Pretty robust though, I hear the PSU in these is build like a tank and is highly reliable. So seems to be the case with the dual floppy drive, I haven't even opened the machine yet and everything just works and it has been sitting in a (unheated) house since 2004 and was probably left untouched long before that. It's amazing how much abuse these old things can take.

brostenen wrote:

Did a rebuild of my 486dx2-80. Were I moved it to another AT case. Finally I can begin the "486dx-33-Pure-ISA" build that have b […]
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Did a rebuild of my 486dx2-80. Were I moved it to another AT case. Finally I can begin the "486dx-33-Pure-ISA" build that have been sitting in a box, just waiting for it to be a complete machine. Hardest thing was to source AT cases these last couple of years.

First step was to solder in a new battery. I have begun using 3.6 volt rechargeable 2032 batteries, instead of them old barrel types. I cleaned up the board by removing old solder, cue tip and isopropyl alcohol and finally soldering in the new battery. When the build is done, I will make a post or log or something of this machine.

486-DX33-08.jpg

486-DX33-09.jpg

Be aware, that lithium cells have vastly different charging characteristics and will most likely be dead quite quickly when they get ticklecharged from the board like the NiCds. If you use them as a direct replacement they will get overcharged/overdischarged with prolonged use-/storagetime.

I think it was a poor decision to put a sealed battery there. Rechargeable or not. The best solution is to install a socket, so you can easily remove the battery for storage. I don't leave batteries in machines, even restored ones, even new ones.

luckybob wrote:

I think it was a poor decision to put a sealed battery there. Rechargeable or not. The best solution is to install a socket, so you can easily remove the battery for storage. I don't leave batteries in machines, even restored ones, even new ones.

Fair point. I will have to keep in mind for my future repairs.

Well... I ran a previous motherboard for a half year without issue, before I sold it to raise money for Amiga stuff. On the other hand. I am more into tinkering with PC stuff than actually gaming multiple hours in row. Normally, I just use my computers to game a single level, and then put them back in the closet for storage. Those times they are turned on the longest, are when I set up operating systems and configure them. No gaming through an entire weekend at my place. That is what I have my RaspberryPI for. 😉 All my vintage PC's are purely to get that nostalgia trip down memory lane.

brostenen wrote:

Well... I ran a previous motherboard for a half year without issue, before I sold it to raise money for Amiga stuff. On the other hand. I am more into tinkering with PC stuff than actually gaming multiple hours in row. Normally, I just use my computers to game a single level, and then put them back in the closet for storage. Those times they are turned on the longest, are when I set up operating systems and configure them. No gaming through an entire weekend at my place. That is what I have my RaspberryPI for. 😉 All my vintage PC's are purely to get that nostalgia trip down memory lane.

Mine serve a multitude of purposes. Gaming, Research into the evolution of various technologies (especially 3D graphics), practical demonstrations of old software in their original habitat for YouTube. etc.

TheAbandonwareGuy wrote:

brostenen wrote:

All my vintage PC's are purely to get that nostalgia trip down memory lane.

Mine serve a multitude of purposes. Gaming, Research into the evolution of various technologies (especially 3D graphics), practical demonstrations of old software in their original habitat for YouTube. etc.

Interesting. In my case, it is retro gaming, nostalgia trips, some fact checking (if I am writing an article on something, say, CGA), some writing (I have soft spot for amber screens, distraction-free writing on mono DOS machines is something I occasionally do).

Started messing with autoexec and config.sys for the first time to get sound in dos. Quite pleased when I got it working and noise drivers too.

Added a StarTech 5.25" drive bay for 3.5" hard drives in my Pentium 4 machine, so, when I eventually start making periodic backups of my retro gaming machines' hard drives, I can easily do so. 😀