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Hi all, Small programming question for the PET. The 'Diag Sense' line on the PET userport is connected to pin 9, PA7 on one of the 6520s. This line is an input by default, but the schematics I've seen indicate this line as bidirectional. Anyone know if it is possible to set this line as an...

Looking to sell this Wang workstation, I believe the model number is 2246-C although the sticker is gone. I got this years ago intending to repair and do something with it but looks like we will be moving house soon and it's just too big and heavy to bring along. Current status: I don't see a...

Hello again, Have my model 1 almost working now, with exception of the L2 ROM board. This is a 3-chip board, version 1.2 roms. If I have the romulator z80 connected and replacing the address space 0x0000-0x2FFF, It boots and runs. I am wondering about how the ROM select actually works for the...

Looking for a CoCo 1 or 2, working or not, cosmetic condition not critical. Will pay for shipping to California, USA. Thanks.

Hello, I'm in the process of fixing a Model 1 which has a bad character ROM. It's only slightly bad - most of the characters look fine, except some have a single dot which I don't think should be there. I was able to read in the character ROM and re-render all the characters as an image, which...

Hi all, Looking for a little information on a Wang Terminal - It looks similar to pictures of a Wang 5506 I've seen in dredging around the internet, but I'm not completely sure, I couldn't find an obvious model number anywhere on the unit. There is a serial number KZ4561, but that didn't yield...

Whenever I see a device that uses a barrel-jack DC adapter where the center pin is negative and the shield is positive, I feel a mild annoyance. Seems like the device is daring me to destroy it by accident. I was wondering if there was an actual engineering reason for doing this, apart from...

Hi all, Looking for a decent way to transfer the contents of the HD on a Canon Innovabook 10C, circa '94. It has the beginnings of a game I was trying to make using Turbo C back then, along with some other things it would be nice to keep. Copied a few things over with floppies and a bridge...

Hi all, For the PET aficionados here, wanted to let you know that I recently did a redesign of the PETdisk MAX device to use a new, more capable microcontroller (ESP32 vs ATMega1284) and I'm looking for a few people who would like to help test out the new version with some PETs. The primary...

Looking for a replacement VIC chip for a VIC-20. Have one with a missing VIC, would like to get it going again. Thanks. Located in California, US

Hi all, Doing some repairs on yet another PET, this time it's a 2001-8, the earlier board with 28-pin ROM sockets. Before doing some more in depth investigation, here's a quick report of the symptoms. The CRT has some issues, looks like the raster is messed up in some way. But I unplugged the...

Hi all, I recently made a little board to bring the video signal from a PET to an RGB2HDMI board, using a custom profile on the device. Currently this works on a homebrew protoboard, but will get the pcbs in a few days. It uses a single 74LS02 to combine the vsync and hsync into a composite sync...

Hi all, I have an SE/30 which I've been working on on and off, it is stubbornly simasimac and I'm trying to diagnose it. It would be much easier if I could test the board without putting it back into the chassis every time, does anyone know of a source for an extension cable for an SE/30 logic...

Hello, I wanted to see if it was possible to power a PET 2001-N board directly from a bench supply instead of going through the transformer/regulators. On this machine I was using a ROMulator to replace ram, so I first removed all the RAM on the board, which as far as I could tell was the only...

I have bare RaSCSI v2.3 boards that will be arriving from the pcb fab in a few days. RaSCSI is a project which uses a Raspberry PI as an emulated SCSI device, more info here: https://github.com/akuker/RASCSI I ordered 5 of the boards, will keep 2 to build and can pass along the other 3, for the...

Hi all, I finally got around to attempting to fix a 2001-8 that I got years ago. This one has had a bit of a rough ride, the case is very rusted and the board itself had all of its ROMs pillaged. The CRT is also disconnected, it's in storage somewhere and need to dig that out. Using a ROMulator...

Hi all, Can anyone help point out the visual differences between an Apple II (original) and II plus motherboards? I may get the opportunity to buy an original II, and want to be able to tell the difference. Looked at a few examples but wasn't sure if I could spot the giveaway differences. Any...

I ordered a few BlueSCSI PCBs from gerbers, looks like I will have 3 extra. If anyone is interested I can send one to you for postage. Located in California, US.

I was curious if there were any projects around to directly interface a 5.25" floppy drive, hd or otherwise, as a modern USB storage device? I imagine you could do this either by using a FDD ISA controller card, and then interfacing with that, or by talking directly to the floppy itself. This...

If any mods are around and can deal with the 'herbsandcure' spambot, that would be nice. Thanks