IBM PCjr Circuit Board 3000-0004 REV 1

[FlaminJoe]

Hi all,

I saw this on eBay and out of curiosity I'm wondering what it is. The seller claims in the listing "Pulled from working PC Jr." and while I don't have a full grasp of the inner working of the PCjr and it's attachments, I'm stumped as to where it would fit in and what purpose it serves as all it appears to do is change connector. Not looking to buy it just genuinely curious.

https://www.ebay.com/itm/IBM-PC-JR-CIRC ... 2622567947

[alanh]

I saw this too. Not sure where he got the PCjr reference but I am certain the seller is mistaken. The ground and power pins on that card do not line up with the PCjr side-car connector at all. It's from some other machine type.

[FlaminJoe]

Yeah I figured it didn't seem right. Even if it fitted into the side-card connector it seems like an odd PCB to having hanging out the side.

Out of further curiosity I've emailed the seller to see what's up.

[FlaminJoe]

I just received this response from the seller:

It was definitely pulled from a PC jr. After additional research, I am told it goes to a Tekmar/Quadram Drive 2 expansion unit. I don't know if that is true.

I raised the price, not because you asked about, but because there do not seem to be any others. Because you asked about the item, I will honor the original price if you are interested.

I did a little Googling of the Tekmar/Quadram Drive 2 expansion unit and found this link over at VCF stating the same but this may be where the seller got his information. Nothing definite but at least we can now see what other board it connects too.

http://www.vcfed.org/forum/showthread.p ... t-for-what

Still very unsure what to make of it.

[alanh]

OK, I stand corrected. I actually have a Quadram expansion for one of my Jrs. I looked in it and posted a photo over on the VCF thread.

[alanh]

I actually find the eBay seller's response even more humorous now. He doesn't really understand what he has. I consider myself fairly plugged in to the PCjr community (here, duh!) and I can count the people I know with any double-decker expansion on one hand. And to hold out for a buyer that has a busted Tekmar/Quadram upper deck and they just need the bridge board... well, you'd have a better chance of winning the lottery - twice in one week!

[FlaminJoe]

Yes I found his response quite interesting. He's basically offering it to me for a discount but then what would I do with it? I didn't even know what it was!

[Brutman]

I think it's for a Racore/Rapport/Quadram expansion chassis. The long flat board just brings the signals to the sidecar over to the memory board, which is on the other side of the machine.