Recent content by Dunwood84

well I now have a operational iic, but not the one I originally brought. I sourced a broken iic for parts. but i'd decided to see what was wrong with it. It was advertised as non functional with no lights. It turned out to be a blown fuse located in F1. It seems to have a ALPS keyboard, a ram...

well I tried all changeable chips from the doner iic and its still the same image.

I have a oscilloscope that showed that one of the ram chips were marginal. and a volt meter that showed that the board was getting the correct voltages. I there somewhere particular i should check next?

The Monitor Rom has the part number 342-0272-A. it is a VIA chip. i Tried a flashed rom with 4x on it and it came up the same way. Different 6502 cpu made no difference. There was one bac RAM chip, but it still shows the image. Also tried a flashed character rom (Original is 342-0273-A) but...

hmm ok when I plug in the keyboard, i just get the checkerboard image with no characters on it. what should i look for on the keyboard? there is no ic's on the keyboard.

Hi all, i have a Apple IIC that only puts out a checkerboard image. no sound from the floppy drive and no sound from the speaker. the image is stationary. sometimes there are characters on the white square, sometimes there is no characters. the image appears even when the floppy drive and...

​For anybody interested, here are some photo's of my NEC PB-80S31 And this is the circuit board. From what I have found, the blue box is a Z80 Compatible CPU running at 4Mhz, the Yellow box has the ram, The red box is a Double Density Floppy Disk Controller, the orange box is a...

Hi all, I am in the process of fixing up this NEC PC-8801 that I found locally. The first issue that I had to fixed was the keyboard not working correctly. When I press any key at all on it, it showed a different character on the screen. Once i pulled the keyboard apart, I found a Faulty...

Here is a better photo of the screen that shows the problem that i am having with my Laser128

Here it is again. sorry the link is broken for some reason

Lets try this again

Hi There i am having a issue with my Laser 128. whenever i try to turn it on i get this on the screen. no sound or action from the disk drive https://photos.google.com/photo/AF1QipMa_cFHXzZfEFIERm64r6PbJvM0CjuJb7IHxNCA if someone could point me in the direction of where to check, it would be good

Hi there, I am chasing up some information on my Diversified Technology pc that I recently got. (I actually got two of them, but this one is complete and runs) It looks like it was built as a Oscilloscope due to the three ISA and one PCI card all hooked together with a ribbon cable, is there a...

Hi there, I’ve got a Commodore PC40-iii that I’m having a strange problem with. No matter what floppy drive I put in (360k, 720k or 1.44mb) it will not boot from it, but if I put same drive in my Pentium 75 machine, it works like a charm. I’ve tried the straight thru floppy cable that came with...