Had another Roland sound module on the bench today, this time an SC-55 mkII.

It had the usual nasty glue under the 2200uF capacitor. The glue had turned conductive, although it was measuring in the mega ohms so I don't think it was causing any shorts.

I removed the cap and cleaned off the glue all the same. The capacitor tested at 1898 uF, a little on the lower side. Unfortunately I didn't have any 16V 2200uF capacitors on hand, so I opted to put it back for now. I'll order some caps and replace it next time I have this unit open.

The other issue are the buttons. The power/standby button was completely non-responsive as were the key shift buttons. Some of the other buttons were intermittent but mostly usable.

I opted to disassemble both the power switch and one of the key shift buttons and clean the metal contact inside. They were quite corroded.

Roland uses switches with only two pins instead of the more standard 4 pin versions. I'm going to look into buying a supply of these if I can find compatible switches. Straight replacement is probably the easier option than disassembly and cleaning.

Most of the switches measured at about 50 Ω up to 1000 Ω. Usable but not ideal. Whereas the two I polished now measure only 0.5 Ω.

Do they center the pins on the footprint or something, because it would seem easy to snip 2 pins of a 4 pin to me.

The curse of low voltage, low current switches and buttons is that they don't self clean from slight arcing.... so you may be able to clean them after removal by rigging up a breadboard circuit to switch 12V to an automotive bulb, and hammer them a few times and that might be enough of a "blast out" to keep them good for a while.

So I've been going through my already greatly thinned out collection seeing what works and what doesn't.

This is HP Pavillion didn't work. Dead motherboard. But I remembered I had a very compact low end PCCHips M810DLU lying around (that I nearly threw away at one point because it seemed extra pointless). Sure enough I was able to cram it in there. I had to do some goofy stuff like solder the CPU fan directly to the motherboard after removing the header because the header was a clearance issue, and I also had to modify the cases front panel wiring. The Socket A heatsink/fan combo that was on the board was too large, but luckily the Pentium 3 cooler from the machines original motherboard clipped on just fine. The IO Shield I had for this motherboard was SUPER rusty so I sanded it down with steel wool and spray painted it, which actually turned out fantastic. The PCCHips board has a Athlon 1500+ (1.33ghz) and 512MB of RAM installed, I intend to put Windows ME on this machine.

Now the question is:

* Will the much smaller Pentium3 heatsink be enough to cooler an Athlon 1500? My guess is its going to be very borderline. I might have to mess around with underclocking/undervolting this thing.
* Will the anemic 100 watt max continous output PSU explode trying to power it?

I like that this grey on translucent grey front matches well with a black optical drive, which are in much more abundant supply (especially for DVD-ROM drives).

Sadly the serial port on the front isn't hooked up as the PCChips board doesn't have a header for serial. I'd like to put a PCI GPU in it, but I think I'm already pushing that PSU pretty hard. I had a random fake Dell Soundblaster Live lying around, I went ahead and installed that as I wouldn't use that card in any serious build.

andrea wrote on Yesterday, 17:36:

You know in cartoons where a little devil pops up on the character's shoulder to give him bad ideas? […]
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ChrisK wrote on Yesterday, 16:56:

Now I'm thinking about replacing the NB with a replacement.
It's not worth the cost and effort by any means, but wouldn't it be fun if it really worked in the end? 😉

You know in cartoons where a little devil pops up on the character's shoulder to give him bad ideas?

693/596 are pin-compatible with 440bx/zx and piix4, only the bios is different.

A lot of 440bx-based laptops suffered from crumbling plastic but are otherwise working

And most importantly a variant of your board with a 440ZX exists https://theretroweb.com/motherboards/s/ecs-p6zxt-me

😈

Whoohoo, options, options. Sounds like the bad little guy spoke to me 😉.

Sounds tempting, but I'm not even sure this will be running again if it was replaced 1:1. Although the board itself doesn't seem to have any other damage I don't know the condition before that little "accident" to the NB happened. Who knows what else lies in the hidden there.
So it would be a complete shot in the dark given I even get it managed to replace the NB alone.

Is it known if there are any surrounding components differing between a VIA and an Intel setup? Pin compatibility itself must not mean everything else is going to be the same.
There are also two revisions of this board. The newer v2.x comes with the 693A also allowing 133 MHz FSB, but also having some noticable changes in layout (some added components, Intel/Cyrix jumper, and maybe more), while the older v1.x uses the non-A variant. Mine is the older one.
All in all I'm not sure if a change to Intel or even the 693A can have success without investing more time into this that I'm willing/able to do. If any at all considering the board revision.

Nevertheless I have started a quotation for the 693 because I also need some more components for other projects.
If I can get one of those does anyone know if these come with BGA balls (the chip will likely be "used" condition) or if these need to be reballed first?
Because if a reball is necessary I'm not sure what ball size these chips require. Having had a look into some VIA datasheets I'd say these are most likely 0.6mm but there's no definitive parameter given. Or I may just have overlooked it.
Haven't checked Intel's datasheets yet, though...

Regarding old equipment suitable as a donor: I find it quite difficult to find old damaged hardware around here for sale. I once bought a severly damaged i810 mainboard for salvaging parts years ago in the bay. But that was it. Most stuff like this goes in larger lots for scrapping and at insane prices and is mainly much newer these days. If you wanted to buy only one or two pieces it gets complicated. So yeah, this is that. May be I just don't connect the right sources (saying as someone completely out of any social networking stuff). Who knows.

ChrisK wrote on Yesterday, 16:56:

Nice!
Just out of curiosity: what's your specific intention with this project?

Nexxen wrote on Yesterday, 17:29:

Like above, some more info? 😀

I'm not done yet, but what comes out of this is a page where you get the R9800Pro PCB in it's blank state and you can see all parts on it with their identifiers (like U76), their values and if present part numbers. I'm also adding a description per part as to what it's important for.

This way anybody, even without the ability to read schematics, can find out what part is broken / missing. I'll add filtering by component type (IC, resistor, cap etc.) and per schematic region (e.g., power supply)

Some way to go still, but it's more about the tooling to get there than figuring out the parts. The 9800Pro is baiscally the same schematic as the 9700 Pro and that's widely available. Also the identifiers for parts match 1:1 for most part..

We don't have board views for these cards, so I'm taking matters into my own hand.. And that PCB comes from a drop dead 9800 pro. So I use it for this.

tehsiggi wrote on Today, 08:26:

I'm not done yet, but what comes out of this is a page where you get the R9800Pro PCB in it's blank state and you can see all pa […]
Show full quote

I'm not done yet, but what comes out of this is a page where you get the R9800Pro PCB in it's blank state and you can see all parts on it with their identifiers (like U76), their values and if present part numbers. I'm also adding a description per part as to what it's important for.

This way anybody, even without the ability to read schematics, can find out what part is broken / missing. I'll add filtering by component type (IC, resistor, cap etc.) and per schematic region (e.g., power supply)

Some way to go still, but it's more about the tooling to get there than figuring out the parts. The 9800Pro is baiscally the same schematic as the 9700 Pro and that's widely available. Also the identifiers for parts match 1:1 for most part..

We don't have board views for these cards, so I'm taking matters into my own hand.. And that PCB comes from a drop dead 9800 pro. So I use it for this.

Amazing! Can’t wait for this 😀

Not quite "retro activity" but I was digging through my bins.
Found these two SXLC2 processors. Could someone with more experience tell me if they are 5v-Operating or the 5v-Tolerant types?

My initial research tells me they are 5v-operating.
If they are the 5v-Operating, may use them for actual "retro activity."

BitWrangler wrote on Today, 05:42:

Do they center the pins on the footprint or something, because it would seem easy to snip 2 pins of a 4 pin to me.

The pins on these switches are in the centres of the sides. Unfortunately trying to use 4-pin connectors wouldn't work, even with two pins snipped off.

The curse of low voltage, low current switches and buttons is that they don't self clean from slight arcing.... so you may be able to clean them after removal by rigging up a breadboard circuit to switch 12V to an automotive bulb, and hammer them a few times and that might be enough of a "blast out" to keep them good for a while.

Perhaps. I'm good with just giving them a good clean. There is something therapeutic about disassembling and polishing the contacts. xD

Shponglefan wrote on Yesterday, 17:21:

ChrisK wrote on Yesterday, 16:56:

Still had this board around so I thought why not give it a shot with my new self-made(TM) preheating station (which for itself was a long planned project but only got realized within the last weeks):

Can you share more about how you set this up?

I've long considered getting a board heater and also trying to rig something up for BGA chip rework. I'm really curious what your set up is like.

Nexxen wrote on Yesterday, 17:29:

Like above, some more info? 😀

Btw, what diameter are the pads and the solder balls you are going to use?

Will do asap.
Give me a moment.

I got a Gigabyte K8VT800 Pro motherboard that has VT8237 south bridge and it does not detect sata 2 or 3 drives, so out of curiosity I salaveged a VT8237R Plus chip and reballed and put it on this board,
now it detects those drives without doing any modifaction to the bios.

data transfer is limited to ATA 133 speed though.

Wow, excellent information!
Now, where to put this to not forget...?

Edit: What ball size did you use?

0.5MM is the right size however the universal stencil that matched the pads had 0.6mm holes but still I used 0.5mm solder balls.

yourepicfailure wrote on Today, 09:46:

Not quite "retro activity" but I was digging through my bins. Found these two SXLC2 processors. Could someone with more experien […]
Show full quote

Not quite "retro activity" but I was digging through my bins.
Found these two SXLC2 processors. Could someone with more experience tell me if they are 5v-Operating or the 5v-Tolerant types?

The attachment 486SXLC2-40.jpg is no longer available

My initial research tells me they are 5v-operating.
If they are the 5v-Operating, may use them for actual "retro activity."

Looks nice.
Hope it lands 100% ok.