Recent content by dkjones96

Tried the chip swap and, surprisingly, didn't even get the death gong? I also tried every combination of resistors I could on the bottom and got zero out of the machine. @hyperneogeo you are certain you got a death gong out of it?

That will 100% be the path I take. The new cache chips are in and will be swapped out, possibly end of the month. Gotta see when I get the courage to do it! I also now have a set of soldering tweezers so swapping the 0-ohm resistors will be a cinch. Last bit of research I need to do is make...

I am thinking of trying this same upgrade! Ha! Even ordered the same 128Kx8 chips. My GAL chip isn't socketed but I did notice that there are some R positions underneath the cache board with 0 ohm resistors across them. I'm guessing that the cache chip has to have a jumper setting change to...

Amazing, that was it! Popped a battery in there and it booted right up. Thank you!

I'm currently troubleshooting an LC475. Should the machine start up when the power supply is switched on or should it use soft power like most other 040 machines? This motherboard came to me with a destroyed R85 resistor. It's the big 6.8 ohm guy by the sound chip. I replaced it, along with...

Fortunately I don't think most of us use our compacts enough to 'really' worry about wearing out the CRTs. Keep the brightness down and you are good for 5K hours, easy. Might even squeeze 10-15K if you aren't afraid of a little burn-in and don't mind cranking up the brightness a bit later in its...

Fortunately they come up a lot so some decent prices can be had if you are patient. They come up WAY more than any other analog board and are much cheaper than most.

Only the red wire to the anode has high voltage on it. The deflection coils in the yoke all run on about 30V so as long as you don't mess with the big red wire the yoke is relatively safe.

Is it parallel on the left but not the right or is the whole image turned? If the whole image is turned you can correct that by loosening the yoke clamp on the tube neck and turning it a bit. It might be sticky after all these years but it'll come loose. Not sure why but pretty much all of my...

@ttb I did end up undoing it and then going with the old preferred way which is option 1 above. I kept having problems with a pair of diodes overheating an electrolytic capacitor in almost the dead center of the analog board. It runs crazy hot at 84v and stays that way even when the computer is...

I thought I'd add this little update. This mod seems to be working just fine so far on the Rev D board outside of a warm reboot sync problem that I can't trace. None of the ICs or resistors, outside of the really hot area below, get above ~115F so it shouldn't be drift or anything like that...

I have upgraded this guy to a Color Classic II logic board(couldn't stand the gimped stock CC performance) and with the 256K expansion I have 768K VRAM. As for screen distortion, it's the photo and I'll try to get a better one. I'm upping the dissipation rating of a resistor that is dissipating...

Alright, RP6 needs changed out, you can only get 72V max with it as-is. Swap RP6 to a 752(7.5K) 1206 resistor and you are in business. Looks beautiful! I had only an 822 1206 available but it requires PP1 to be turned down all the way to get 84V. Only problem left is RF11 which runs over 300F...

So, I don't know if I was just imagining smoke or what but there wasn't anything overheated or burnt when I very thoroughly looked over the board. I did have a wiring error on my part but it was signal level and what caused me to have no screen before. It looks like I need to up the voltage a...

Tried to do this mod on a revision D board and got smoke. Oops! I went with the 640x480 posting at Powercc.org. Here is a list of the parts mentioned to replace and what the Rev D board has: CL9 and CL10 - 3.3uF - Changed to 2.2uF and 1.8uF respectively. DL21 and DL22 - Changed to single 18V...