IRIX Network Forums
I have found the connector for SGI Fuel internal LVD SCSI port, need to develop it! - Printable Version

+- IRIX Network Forums (//forums.irixnet.org)
+-- Forum: SGI/MIPS (//forums.irixnet.org/forum-3.html)
+--- Forum: Hardware/Triage/Repair (//forums.irixnet.org/forum-11.html)
+--- Thread: I have found the connector for SGI Fuel internal LVD SCSI port, need to develop it! (/thread-4047.html)


I have found the connector for SGI Fuel internal LVD SCSI port, need to develop it! - weblacky - 09-07-2023

Hi All,
Big news!  I just received a part in the mail that I suspicioned would be fully compatible with the odd looking 68 pin SCSI connector that is present inside every SGI Fuel. My hunch was correct in that this connector has gone through a couple different vendors/manufacturers and while the same connector is not available that can be soldered onto the Fuel's existing PCB footprint (no SMD version left, it was retired too long ago) connectors to attach to the Fuel are available:

But I was able to locate an active IDC crimp version 
   

And an active straight through-hole solder version. 
   

I also found the right angle version but when I tested it, it points the wrong way. So the pins literally dig into the nearby PCI-X slot, so unfortunately while the right angle version would be much easier to put on a PCB, to some extent, it's not going to work because of the tolerances inside the Fuel. 

There's at least 1,000 of each part available, as of the day I posted this, on Digikey.

I've just checked the solder version and it perfectly fits in the SCSI port. I did not buy the IDC version but it's of the exact same family. With this information someone can now create Fuel 68-pin SCSI adapter to standard LVD 68 pin SCSI connector. My problem is twofold. Number one I can't find the part for the standard 68 pin LVD SCSI connector, as odd as that sounds, sold anywhere in the US, I did find one in the UK (https://sg.element14.com/mh-connectors/3700-0200-15/socket-scsi2-pcb-straight-68way/dp/2373611). 

And number two I have no experience producing any kind of high density communication PCB adapter that needs very thin lines laid out, close together, with all of that. So unfortunately as much as I'd love to capitalize on this I need to pass this off to someone else who will actually do this. So looking at the big hitters in the group to contact me if you have actual experience designing PCBs.

Due to the tight tolerance is the area I assume the adapter will have to have a body similar to this:
   


I did have a mounting idea where you use the local mainboard mounting screw hole and and an standoff Hex extension to secure the adapter board to the port with the original mainboard screw to keep the adapter's weight from working the SCSI connector out of the port during transport or over time.

We know we all hate the proprietary cable, it's too long, has too many ports, gets ruined too easily, the first connector is too low on it, and probably more. So I think this would be a fantastic idea as many have suggested before, I'm just unable to do it as much as that pains me. If somebody wants to partner, I'm all for it. I can even put up some funds to do a board run I just don't have a chance with my level of experience with the software necessary to design a successful PCB product at this time. I wish it were otherwise but I don't want to let my inability to do it stop somebody from getting this to market ASAP.

I prefer whoever contacts me be able to prove that they in fact have done something like this before with some form of online design they already have available so I know you have the ability.  Any professionals out there that do this for a living please think about taking this on. Even as a soldering kit, it's worth doing. If you want to just designed the board and make someone else buy a PCBway production run on it and the end-user or myself has to solder it, I still call that a win! We just need to get this going.  If you're a designer for higher and you want to just design it and sell me the design, we can talk.

Thanks!

RE: I have found the connector for SGI Fuel internal LVD SCSI port, need to develop it! - robespierre - 09-07-2023

I believe that the 68-pin micro-CHAMP was used in RS/6000 machines? But I can't guarantee that the pinout is compatible.
IEC.net does sell cables with that connector type.

RE: I have found the connector for SGI Fuel internal LVD SCSI port, need to develop it! - kubatyszko - 09-17-2023

hi there, way ahead of you all Wink

The connector itself isn’t that hard to find, as long as you get the non-latched version.
I have a stock of them as well and I’m starting a small batch run of actual CABLES.

not adapters this time.
Didn’t want to spend time designing adapters for this tiny market (which is much smaller than the ATX adapter one).
and yes, Robespierre is also correct,
in fact I’m using an RS6000 cable in my Fuel, it comes with the same connector on both ends so I had to cut one off.

cheers

RE: I have found the connector for SGI Fuel internal LVD SCSI port, need to develop it! - weblacky - 09-17-2023

(09-17-2023, 09:53 PM)kubatyszko Wrote:  hi there, way ahead of you all Wink

The connector itself isn’t that hard to find, as long as you get the non-latched version.
I have a stock of them as well and I’m starting a small batch run of actual CABLES.

not adapters this time.
Didn’t want to spend time designing adapters for this tiny market (which is much smaller than the ATX adapter one).
and yes, Robespierre is also correct,
in fact I’m using an RS6000 cable in my Fuel, it comes with the same connector on both ends so I had to cut one off.

cheers

I never found an actively produced IDC crimp version, only solderable through-pin straight and right-angled version for sale/production.

You must have one excellent IDC crimp jig, I would hate to try to crimp the 68 pin LVD cables I've seen. I can barely get normal 50 and 64 pin 1.27 pitch ribbon cables perfectly straight with the minor amount of tools I have. I don't want to attempt to crimp an even more narrow gauge cable like an LVD cable...nope...you're welcome to that mess!

An adapter card would be better so you can replace the SCSI cable at will...which what keeps getting damaged in the drive bay swing.  I have 4 of the IBM cables already (everyone already knows that suggestion)...for emergencies...it doesn't solve the problem.  The IBMs currently run about $55 a cable or so on eBay, unless you can assemble them for cheaper and you don't have a huge error rate in crimping, that doesn't sound economical to me.  Then again $60 for an adapter that you have to also then buy an LVD cable to attach to it...yeah...that makes more sense.  Then when the cable runs in to the drive swing...just buy a new 68-pin LVD cable and keep going on.  Replacing one proprietary cable with the same proprietary cable just gives you a second shot to screw it up. And every new owner has about a 50% to 70% chance of damaging that cable because they're not used to looking out for it every time a Fuel system changes hands/owners.  

Solve the problem at the source.  I'm still willing to partner for an adapter.

RE: I have found the connector for SGI Fuel internal LVD SCSI port, need to develop it! - kubatyszko - 10-21-2023

oh well, I am happy to present a one-of-a-kind brand new, SCSI cable for Fuel.
Freshly assembled by yours truly.
Now I need to find a reliable source of scsi cables :-)


   

Cheers