Minutemanqvs wrote on 2023-12-23, 13:28:

I wonder if people really used these AMR/ACR slots...I have never seen one populated in real life.

I've only seen a softmodem and a sound "card" in that slot, both came optionally with the motherboard and were not something you could buy from a shelf in a box. When that sound device was playing music the cpu usage was noticeable.

Removed all components from a soundcard and then removed the soldermask to get a perfect view of the traces to reverse engineer it...

Introduced my Amstrad PC4386 to the internet. Went about as well as you might expect for a 20MHz 386 with 4MB of memory. Worked (kinda) and only looked at a couple of simple sites like frogfind.com and textfiles.com so nothing too taxing. And as it was running IE3 on WfW3.11 I doubt much else would even load in any meaningful way.

Biggest pain was getting the thing to fire up. It kept moaning about keyboard errors. Now given that they keyboards and keyboard protocols on these things is proprietary this is not a good sign. Managed to persuade it into working through, looks like the pins were just a little oxidised (this would be only its second power up in over a year so such things are to be expected I guess) and not making good contact.

DeoxIT is a good product for that. Sometimes pulling the plug in and out is enough to scrape away at the oxidation as well.

Fixed an Asus P5B Deluxe by recapping four capacitors around the southbridge and BIOS chip.

It had the weirdest error I had ever seen before recapping: the year in BIOS would increase to 2099 right in front of my eyes, yet all other values were normal.

testing the ibm pc365 mainboard that i bought earlier this year
since i don't have the original psu, i buy two atx-at adapter and re-wire one of them to provide 3.3v to mainboard & riser

You have an amazing set of external optical drives.

smtkr wrote on 2023-12-25, 03:21:

You have an amazing set of external optical drives.

A new pick up line? I would consider that an harassment comment... 😀

pan069 wrote on 2023-12-25, 04:21:

smtkr wrote on 2023-12-25, 03:21:

You have an amazing set of external optical drives.

A new pick up line? I would consider that an harassment comment... 😀

It's only harassment if you ask them if they'll take your 3½-inch floppy.

smtkr wrote on 2023-12-25, 03:21:

You have an amazing set of external optical drives.

I also had a small collection of optical drives. I decided to go through and test them last year and found that most of the had failed. One has a laser that couldn't read disks consistently without errors (I did try cleaning it) and the others had problems opening that seemed unrelated to the belt.

CD-ROM drives that "lose the strength" to open

DerBaum wrote on 2023-12-23, 17:59:

Removed all components from a soundcard and then removed the soldermask to get a perfect view of the traces to reverse engineer it...

2023-12-23 18.55.08.jpg

3rd gen Aztech clone?

I have been been working on several projects this christmas and this Atari STm is nearing completion. I got a 4Mb ram upgrade for it from Exxos and proceeded to desolder all the ram chips from the motherboard. This is not a project I recommend for anyone that does not have a desoldering station. Aligning the new pins did possibly take more time than the desoldering. I also did a mod I saw on Adrians digital basement where you ground the A9 adress line on the upgrade board so you just get the original 512k for compability. But instead of drilling a hole in the case I opted to just hot glue a jumper that's (barely) reachable through the cartridge slot and that also clears the shield. I might refine it in the future but it's fine for now.

I also upgraded TOS to 1.04. There are several possible ways to do it, the most common diy-solution is to just write 6 x 27c256 EPROMs but I opted for the less elegant way of modifying 2 x 27C1001:s to use 28 pin sockets since I have a bunch of them. Im going to redo these and move the soldered connections to the underside of the EPROMs so that they dont interfere with the shield. I believe not every revision is compatible with this mod (i believe some are missing a 74-series logic IC) but it works great on my STm.

smtkr wrote on 2023-12-25, 03:21:

You have an amazing set of external optical drives.

It spiral out of control after i'm acquire some PD disk thinking it was some kind of CD (it not)
then I buy some caddy type dvd-ram thinking it should able to read those disk, (also not)
then i asked my friend and he give me an old panasonic lf-d100 (scsi) which can read pd/dvd (2.6)
then since i already had dvd-ram with caddy, why not tried to source some caddy type dvd ram? those are my favorite when they are release but too expensive for a high school student to buy (~200$ for drive is expensive)
then i got a bunch of dvd-ram caddy, i tried to source some external box usb/scsi/firewire for those drive and before i realize, it became a tall leaning tower of optical disk. 😁

Baleog wrote on 2023-12-25, 08:40:

DerBaum wrote on 2023-12-23, 17:59:

Removed all components from a soundcard and then removed the soldermask to get a perfect view of the traces to reverse engineer it...

2023-12-23 18.55.08.jpg

3rd gen Aztech clone?

4th gen (HP variant) 😀

If i succeed in what i am planning it will be a super compact PC104 soundcard in the end... But long way to go 😀

I think i am going the most complex route... i am a visual learner, by doing each step 3 times i really hope to understand why the pcb is designed like it is and get a good result...

I discovered only today that Tyrian has Christmas mode 😀 I guess it suggests that I have been good family man all those years... ....well so far

Playing MicroProse's World Circuit game last two days of fun

Just did some light cleaning...

this is an old AT power supply and it was not working. I had little hope but I thought I may give it a clean anyway and now IT WORKS.
Not sure what was wrong but it was so dirty that maybe the fan was simply stuck - who kows...

Stuck a canopus pure3d I managed to get into my socket 7 build. "DPMI: GetDeviceID returns NULL!!! DPMI: Couldn't get VXDLDR entry point" logs whenever launching a game. On visual inspection, a crystal oscillator looks to have been smacked and is at a 30 degree angle. Rest in peace, canopus, you beautiful 6mb voodoo :'(

DeathRabbit679 wrote on 2023-12-27, 04:19:

On visual inspection, a crystal oscillator looks to have been smacked and is at a 30 degree angle. Rest in peace, canopus, you beautiful 6mb voodoo :'(

If it is just the crystal that should be an easy fix.

Shponglefan wrote on 2023-12-27, 04:25:

DeathRabbit679 wrote on 2023-12-27, 04:19:

On visual inspection, a crystal oscillator looks to have been smacked and is at a 30 degree angle. Rest in peace, canopus, you beautiful 6mb voodoo :'(

If it is just the crystal that should be an easy fix.

For someone who isn't garbage at working with hardware, yeah. For me, attempting to fix it would probably turn it from a somewhat broken card into a completely destroyed card. I am dogshit at electrical debug and barely passable at soldering THT. I'll probably try to move it on down the line for free to someone in town who would stand a legit shot at fixing it then they can use it or sell it for 10000 bucks or whatever haha