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Think it would be possible?

lyonadmiral

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To have a replica PC Expansion Unit Extender Card made using the technical information that is available in the PC HRL?

I know I'm not the only one looking for one.
 
<pipedream?> maybe there should be a wiki entry or some post on hardware wishlists that folks smart enough could look at and see how many votes an item got if they had interest in trying to debug/recreate something for it? I was daydreaming about the same for a Tandy VDI. It'd be similar for the 5161 expansion. or simple stuff like a simm card adapter or usb adapter for XT, etc.

I suppose someone could also just do a kickstarter if they knew enough to get a prototype out there. At least that'd somewhat guarantee some buys if the numbers don't end up adding up.</pipedream>
 
lyonadmiral said:
...a replica PC Expansion Unit Extender Card...
It would help if you described what that is. Otherwise you'll limit your options to only engineers that like playing inside PCs. A description, a photo, a sketch. Even if its something that has never existed before, we get a description.
 
<pipedream?> maybe there should be a wiki entry or some post on hardware wishlists that folks smart enough could look at and see how many votes an item got if they had interest in trying to debug/recreate something for it? I was daydreaming about the same for a Tandy VDI. It'd be similar for the 5161 expansion. or simple stuff like a simm card adapter or usb adapter for XT, etc.

I suppose someone could also just do a kickstarter if they knew enough to get a prototype out there. At least that'd somewhat guarantee some buys if the numbers don't end up adding up.</pipedream>

Way back when, there was an outfit called "Leprechaun" (I think) that used to advertise in 80Micro. They offered an expansion bay for the SX (which would probably work with any Tandy 8-bit slotted box) for $795. There just has some lying around somewhere, but where? I always thought that that was a lot of jack for a tin box.
 
It would help if you described what that is. Otherwise you'll limit your options to only engineers that like playing inside PCs. A description, a photo, a sketch. Even if its something that has never existed before, we get a description.

I will work on getting that posted here; both an image and a detailed description, but in summary; the extender card was a 64 pin connector card that drove a separate bus clock and interface to the IBM 5161 Expansion Unit.
 
Roland has a schematic available for the MIF-IPC-A with all components and layout listed so that made it easy to replicate / improve. Maybe IBM has a similar document for what you are looking for.
 
Roland has a schematic available for the MIF-IPC-A with all components and layout listed so that made it easy to replicate / improve. Maybe IBM has a similar document for what you are looking for.

I figure I should be able to extrapolate everything from the documentation posted on minuszerodegrees.net but I'm just not knowledgeable to know what I'm doing.
 
I figure I should be able to extrapolate everything from the documentation posted on minuszerodegrees.net but I'm just not knowledgeable to know what I'm doing.
The following is enough information for someone (with the required knowledge) to replicate the card:

* An eBay sourced photo of the extender card is at [here].
* The circuit diagram of the card is on pages 18 to 20 (PDF pages 22 to 24) of the document at [here].
* Card dimensions are per page 1-35 (PDF page 54) of the document at [here]. The extender card will be shorter than that shown, per note 2 on the referenced page.

Hopefully the circuit diagram contains no errors.
 
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Thanks! I did post at the suggestion of another over at AmiBAY but no takers who are interested in this undertaking even when $ is involved, any suggestions on who else might want this pet project? I am willing to learn myself but I'm slow.
 
I've got some very nice folks also over at AmiBay and one has agreed to discuss the project with me and to take in on tentatively. I don't know if any of you know Bryce from over on AmiBay, he says with a minimum of 10 cards (extenders only) we're looking at almost $200 per card. I've also thrown out there the possibility of completely re-engineering both sides but that would probably be even more intensive. If you have an interest in, even if it is just a passing fancy please let me know.
 
This is a project that should be undertook as a project that entails BOTH extender and receiver cards, as a lot of us can get back planes anywhere. Having the option to purchase both extender and receiver as a pair would enhance some of our options for expansion, as opposed to a one off if we need an extender card. I'm sure there are some here that would help fund such an endeavor if it were to come through.
 
This is a project that should be undertook as a project that entails BOTH extender and receiver cards, as a lot of us can get back planes anywhere. Having the option to purchase both extender and receiver as a pair would enhance some of our options for expansion, as opposed to a one off if we need an extender card. I'm sure there are some here that would help fund such an endeavor if it were to come through.

In my latest discussion with Bryce over at AmiBay, he thinks it would save allot of money to redesign both cards that would do the same thing, except he needs to find someone who can program CPLD, because while he is good at the PCB part he is not a CPLD programmer.
 
Score!

Score!

One showed up on eBay with a warranty tonight just as I was looking for this card, so I let my impulsiveness get the best of me and I clicked BUY.
 
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