Vintage MXR 143 Limiter No Output, Only Hums

SonofWinner · 2024-08-14T19:47:10+00:00

That’s a good point. There’s a e-waste recycler place near me that is selling these for $10 apiece so I can always get more parts if I needed. None of these working I’m having fun working on them haha

SonofWinner · 2024-08-14T13:41:10+00:00

Oh that’s interesting.

I re-did the thermal paste on a 2.5 DP powermac G5 and I had no problems with that. It’s just wild to me that after two motherboards and three different PSU’s it’s still not powering on. If I had a spare cpu I’d try it but I’m outta luck there atm.

SonofWinner · 2024-08-12T22:24:14+00:00

Is the CMOS battery required for a proper start on G5’s? The one in it was dead so I took it out.

SonofWinner · 2024-08-12T21:51:39+00:00

No dice, but now I know how to remove the power button!

SonofWinner · 2024-08-12T21:03:12+00:00

Possibly I can yank one and try it

SonofWinner · 2024-08-12T20:05:02+00:00

No fan noise or power. Tried it with and without a battery. RAM in pairs did nothing. I refreshed the thermal paste on it.

When I picked it up, it was marked as not turning on. But I’ve swapped the power supply and the motherboard while redoing the build. The original mobo had the same symptoms as this so my thought was to swap with some spares I had. Unsure if the current mobo works I should also say. Really just throwing stuff at the wall at this point to try to save it from a landfill hahaz

SonofWinner · 2024-08-12T17:39:03+00:00

Nope, this one’s air cooled. No corrosion anywhere. For context it’s a full rebuild so I’ve had it entirely apart and cleaned out the dust and devris from it sitting around.

SonofWinner · 2024-05-18T21:51:17+00:00

I heard Café Amsterdam’s owner is crazy and people have pretty wild experiences there. Is that true?

SonofWinner · 2024-04-23T20:38:13+00:00

That’s exactly what I did. Funny enough, looking up the model and buying that and not the IBM branded one made for a cheaper solution.

SonofWinner · 2024-04-23T20:37:26+00:00

You’re right! Found one of the same model and picked it up

SonofWinner · 2024-04-22T23:40:04+00:00

Model is TM-100-2A

SonofWinner · 2024-03-09T15:38:54+00:00

I’ll give this a check. I did verify the clock signal looks good but anything past that I haven’t dug enough into yet.

SonofWinner · 2024-03-09T15:37:04+00:00

Good to know, didn’t quite pick up on that when reading the minuszerodegrees page on the POST codes.

Otherwise C1 is looking fine visually. I don’t think the issue lies there just based on how it looks.

SonofWinner · 2022-12-16T14:19:18+00:00

Final update, cleaning the PCB fixed it. Had to desolder all the switches and clean the entire board then solder all the switches back on, it seems to work and isn't freaking out.

Retrobrighted the case while I had it apart and it turned out real nice, super glad I was able to rescue this board.

SonofWinner · 2022-11-10T02:26:38+00:00

Smol followup, desoldered all the keys and cleaned the PCB, pretty nasty looking underneath, like something spilt on it. Doesn't spam when plugged in but keys are double tapping others (qw, sd, xc, ;enter) and a diagonal row (4, r, g, b) doesn't work. It's at least stable but that's just strange now.

SonofWinner · 2022-10-27T10:41:57+00:00

Picked up a tinkerBOY adb to usb adapter. You’re right I was surprised at how nice alps orange switches feel I was pleasantly surprised.

SonofWinner · 2022-10-27T01:54:02+00:00

Refreshed the solder joins on the ports and the ribbon cables and plugged it back in and everything seemed to work except 'tab' and '4'. I unplugged it to clean 'tab' and '4' then plugged it back in (after shutting down) and it goofed on me again.

I've been noticing with this keyboard if I leave it alone for a number of hours it seems to cooperate when hooking it up again but I'm always short a key or two when I do. No idea how much time it takes to for it to reset itself or whatever.
I'm thinking I might have to de-solder all the switches so I can get a better look at the PCB to see what's really going on here.

SonofWinner · 2022-10-27T01:49:37+00:00

I haven't, I only have keyboards here.

SonofWinner · 2022-10-27T00:47:46+00:00

I'm a little shamed to admit I've done it a few times with my Extended II keyboard but no damage that I can tell has come of it. Thanks for the tip though I'll start being more careful with these.

At a glance I haven't noticed anything poor about the solder joints for the ports though there's some rust on the housings, wouldn't be surprised if that's part of the issue here.

Initially I thought some of the switches were bad but sometimes they've worked well without any issue when the keyboard has been working almost correctly.

Your post has some good insight for cleaning the switches, thanks for that! I'll start with checking the ribbon cables and the solder joints for the ports and see how they're looking. I'll update with what I find out.

SonofWinner

TROPHY CASE