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IBM JX Information Page

What a wonderful resource, especially including the software, thank you so much! I've always wanted a PC JX (I'm a PCjr fan) but sadly IBM dumped their non-selling stock in Australia and New Zealand, and it was never offered in the USA. I have a lot of reading to do!
 
but sadly IBM dumped their non-selling stock in Australia and New Zealand, and it was never offered in the USA. I have a lot of reading to do!

My keeper was serial # lower than 500 and the expansion unit is something like #24. It has a 220V power supply, and no sockets/parts for Kanji or extra VRAM, and the original 360KB BIOS.
So I'm not confident we got dumped with non-selling stock. But it is possible we only got it because they already had a deal with a company in Japan to make them.

I'm also not sure it would've been well received in the US to be honest. The existing fan base would've hated it.
NZ was easy in that respect, as the JR was cancelled before IBM dealers even announced it for sale here.

Edit: oh and I need to do more reading too, lots of articles on that page that I didn't know existed!
 
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I have uploaded my poor attempts at scanning the documents I have.

https://drive.google.com/open?id=1k4ogfpO-9Xz1TQ4G6-KwcF7osbQYrvYA

To explain the letters, which are probably out of order too (sorry):

- He used the diskless JX to help run his shortwave radio gear
- He moved to Mexico around 1989 and took the JX with him, and wanted to get parts an upgrades (not obtainable in US, and the product had been cancelled)
- He moved back to NZ around 1990 and purchased a PS/2 Model 30 286, but wanted to upgrade the JX so the kids could use it

And this documentation is for my diskless JX, which had a serial number ~3400ish.
Prices are assumed to be in NZD.

I also removed the owners name and letterheads from each page.

Edit: Notice the IBM 3.5" "80 track per side" diskette that magically only has a capacity of 360KB.
Edit 2: And Color Paint was a $245 product!
 
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Kinda interested in the question of compatibility. Does PCjr-specific software run out-of-the-box on the JX? How about the other way around (excluding software meant for the Japanese model, of course)?

The JX Sampler disk (on Anthony's site) looks rather like the PCjr Sampler disk, with a similar selection of demonstration programs... but it's prone to freezes when running on a PCjr, at least an emulated one.
 
Kinda interested in the question of compatibility. Does PCjr-specific software run out-of-the-box on the JX? How about the other way around (excluding software meant for the Japanese model, of course)?

The JX Sampler disk (on Anthony's site) looks rather like the PCjr Sampler disk, with a similar selection of demonstration programs... but it's prone to freezes when running on a PCjr, at least an emulated one.

i don't know about the sampler, but I run games like Leisure Suit Larry on mine in PC JR mode with no issue. Mine also came with JX Color Paint, which is just JR Color Paint with a different sticker on the cartridge - they didn't even update the text.
 
Kinda interested in the question of compatibility. Does PCjr-specific software run out-of-the-box on the JX? How about the other way around (excluding software meant for the Japanese model, of course)?

The JX is entirely compatible with the PCjr - you just have to have a 5.25" option. I can run any PCjr software on the JX. I would not be surprise if it is even hardware compatible if we can find the pinouts for the slots. I'd love to make an adapter board to get an IDE sidecar going on a JX.

Anthony
 
I'm not sure if anyone will notice this - but I have found 3 unique ROMs in the IBM JX units so far -

8532K9
8629K1
8732KY

I have imaged the top two - 8532 is 360k 3.5" disks, 8629 and 8732 are both 720k 3.5" disks - not sure what the difference is. I was wondering if anyone had a PCjr System ROM imaged that they could compare to 8532. I have provided my dumps on the web page - http://thepcmuseum.com/ibmjx/ - you can find them under system specs.

I don't have a Jr and I am unable to locate a ROM.

Anthony
 
The PCJR ROM is available on the minuszerodegrees website at http://www.minuszerodegrees.net/rom/rom.htm

I'm not quite on-to-it enough to know what the differences are.

One thing I did notice, is my early model Australian JX has a graphical glitch that seems random during the memory test - but otherwise behaves 100% perfectly (even with Sierra games and PlanetX3 in Tandy mode). My newer models don't have this glitch during POST. Could be an unrelated fault but thought I'd mention it in case someone sees changes in the video code between the two early ROMs.
 
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