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jkua / wheelwriter-interface

Low-level IBM Wheelwriter interface
BSD 3-Clause "New" or "Revised" License
7 stars 0 forks source link

Expansion Connector Sizing/Fit #2

Closed BlipRanger closed 1 month ago

BlipRanger commented 2 months ago

Howdy Jkua, great work on this project! I'm just getting started on fabrication and was wondering, how does the PCB you've designed fit in the little slot? Does it connect via a ribbon cable or is it meant to slot into the 70mm panel area somehow? Just trying to wrap my head around the design before I start milling. Thanks!

jkua commented 1 month ago

Hi! I've added some notes and images to the pcb README. The board is designed to attach to the expansion housing that came with the original expansion boards. It was a plastic housing that clipped onto the back of the Wheelwriter.

And yes, you'd need to build a cable to connect from the Wheelwriter expansion port to this interface board. I added the relevant part numbers to the README as well.

Please do note that I have not tested the v2 design! It's not a terribly complex design, but it's overengineered as I originally thought I had some noise problems with the prototype breadboard. Those issues turned out to be due to a counterfeit level translator I was using (don't buy ICs off random sellers on Amazon!). I'll eventually get around to assembling and testing the v2 design since I fabbed the board and purchased all the components, but future builds will likely go back to a simpler design more like the prototype breadboard.

BlipRanger commented 1 month ago

Ah haha, all good, I've ordered everything for it and will likely have it tested out this week, so I'll let you know how it goes! I'm fine with being a guinea pig here for this as it's such a niche project. Mine is a Wheelwriter 6 which has the little door on the top for the expansion connection so we'll see how that goes. I got everything from Digikey, so hopefully no counterfits!

jkua commented 1 month ago

Great! Please do report back! It is a very niche project with just a few people working on it, as far as I know. Hopefully more once this matures a bit.

I got everything from Digikey, so hopefully no counterfits!

I've never had any problems with Digikey in all my years; I was just impatient (and cheap) this one time and it really bit me! It took awhile to figure out that that part was the problem and then I forgot about it since my work on the project is very intermittent!

I just got my Wheelwriter 3 back up and running as the solenoid cap on the print hammer had finally crumbled to dust.

BlipRanger commented 1 month ago

Hi! I come bearing an update! I attempted to mill my own PCB based on your v2 design and that didn't go all that well (it was my first real attempt at CNC-milling a board). I ended up ordering a set of them from online and finished the soldering today. I can confirm that it works quite well in my initial testing. I may re-try milling but with your v1 design since it can be smaller.

jkua commented 1 month ago

Thanks for the report! I really appreciate it! Happy to hear that the board works!