NeXT
Veteran Member
Got anything used? 
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Four-Phase Systems IV/90
- Thread starter NeXT
- Start date
Chuck(G)
25k Member
Don't think so, but I'll have a look... Most likely T&B, or Amp, not 3M...
NeXT
Veteran Member
This machine is far beyond the state of museum quality, so a make/model matching parts is not my top priority.
Chuck(G)
25k Member
Card-edge connectors seem to be on the edge of obsolescence, so a lot of variation isn't possible. Worst, case, you may have to concoct your own solution (maybe a bracket?) that doesn't involve a panel-mount connector.
NeXT
Veteran Member
A suggestion was steal pins out of another connector, like for a floppy drive.
In theory that works if the pin tooling is identical.
In theory that works if the pin tooling is identical.
Chuck(G)
25k Member
Yeah, I've done that with solder-eye edge connectors, but I'm not sure about IDC ones. I checked my big box o' ribbon cables. I do have one with the flange, but it's a 34 position one.
NeXT
Veteran Member
Well we got a couple of options, none of which are Aliexpress so we indeed have to deal with NOS.
$20 each plus $20 shipping for an identical match
$10 each plus $6.75 shipping
$4 each plus $20 shipping
Surplus Sales unfortunately only has 60 pin (and 44 pin) connectors but they do seem to stock the same connector hoods Four-Phase used.
If it wasn't for those stupid tabs it would be $3 per connector.
$20 each plus $20 shipping for an identical match
$10 each plus $6.75 shipping
$4 each plus $20 shipping
Surplus Sales unfortunately only has 60 pin (and 44 pin) connectors but they do seem to stock the same connector hoods Four-Phase used.
Card Edge Connectors
Computer Accessories, Card Edge Connectors from Surplus Sales of Nebraska. 6 to 100 contacts/pin!
www.surplussales.com
If it wasn't for those stupid tabs it would be $3 per connector.
Chuck(G)
25k Member
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NeXT
Veteran Member
Those are an exact match and shipping is surprisingly reasonable.
I'll see what happens at the end of the week.
I'll see what happens at the end of the week.
NeXT
Veteran Member
Smoke tested the tape formatter and we're running.
I think it's believing that it is both being called by the controller and channel 3 is always active. I'll dig into that later since without a tape drive this is completely useless but I suspect it not being plugged into anything is a possible culprit.
Also, with this added to the power bar it's too much load and I can now trip the Hammond's circuit breaker. Man I wish I had an extra rack now. I'll see if I can reach out to a sheet metal shop next week to have a replacement lid fabricated.
I think it's believing that it is both being called by the controller and channel 3 is always active. I'll dig into that later since without a tape drive this is completely useless but I suspect it not being plugged into anything is a possible culprit.
Also, with this added to the power bar it's too much load and I can now trip the Hammond's circuit breaker. Man I wish I had an extra rack now. I'll see if I can reach out to a sheet metal shop next week to have a replacement lid fabricated.
NeXT
Veteran Member
Drat. Specialty Parts bounced the order because of stock.
Chuck(G)
25k Member
I was afraid that was going to happen. You may have to jerry-rig your own solution.
You may have to jerry-rig your own solution.
NeXT
Veteran Member
I'll email them and see what their current quantity is, then I'll go with the other ebay options I found.
Chuck(G)
25k Member
NeXT
Veteran Member
Nah but thank you for the offer.
I need to dig around and see if I got a female end twist lock hiding somewhere and then I'll have the parts needed to connect it to a higher current outlet. For now I can omit the NP80 and the formatter since we just want to see the CPU come up and that will take off 700 or so watts.
I need to dig around and see if I got a female end twist lock hiding somewhere and then I'll have the parts needed to connect it to a higher current outlet. For now I can omit the NP80 and the formatter since we just want to see the CPU come up and that will take off 700 or so watts.
NeXT
Veteran Member
Well this is an issue.
The new connectors came in and I found that trimming the cable back about three inches I had clean copper.
The bigger problem was that the ribbon cable has shrunk. I can't get a good crimp because even with good alignment you end up crosswiring by the end, and it's shielded cable so it's very expensive to get by the foot.
Edited: Cut 12 inches off both cables, dressed and tried to align it again. No go. It starts off great but it's 0.5 to 1mm narrower by the end and pin 50 can miss the cable entirely. I compared to the original crimp point and there is no alignment issues, so where it WAS crimped for the last 40+ years the cable couldn't shrink. I got no solutions and no cable.
The new connectors came in and I found that trimming the cable back about three inches I had clean copper.
The bigger problem was that the ribbon cable has shrunk. I can't get a good crimp because even with good alignment you end up crosswiring by the end, and it's shielded cable so it's very expensive to get by the foot.
Edited: Cut 12 inches off both cables, dressed and tried to align it again. No go. It starts off great but it's 0.5 to 1mm narrower by the end and pin 50 can miss the cable entirely. I compared to the original crimp point and there is no alignment issues, so where it WAS crimped for the last 40+ years the cable couldn't shrink. I got no solutions and no cable.
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Chuck(G)
25k Member
This means, apparently, that you need some new ribbon cable. I do recall something about how early 3M ribbon was different from everyone else's, but can't put my finger on it. Was it that 3M used solid conductors, while everyone else used stranded? Memory fails me.
NeXT
Veteran Member
This is stranded. The shielding is an extra layer on the backside made of copper mesh and contacting conductor 1 the entire length from within the layering of the cable, so pin 1 would always have to be a shielded ground. You have to peel this extra layer back before crimping or you will just bridge every pin. It's actually quite easy to peel back.
Edited: Comparing the original 3M connector with the new one the conductor spacing is the same as well.
Edited: Comparing the original 3M connector with the new one the conductor spacing is the same as well.
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NeXT
Veteran Member
Talked this over with a few people and one suggestion was to heat the ribbon cable up and try again.
It is quite cold right now and while, erm...shrinkage, might be one possible factor here, the other is that if I heat the cable up it softens the material and I can better pull the ribbon further apart so it will crimp correctly. I can go at this with a hair dryer or wait until the summer and just leave the cable in the car for an afternoon.
The one good thign that did happen today was I was able to verify what cable went where and the orientation.
J3 goes to J3
J4 goes to J4
Pin 1 is correctly marked on both ends.
It is quite cold right now and while, erm...shrinkage, might be one possible factor here, the other is that if I heat the cable up it softens the material and I can better pull the ribbon further apart so it will crimp correctly. I can go at this with a hair dryer or wait until the summer and just leave the cable in the car for an afternoon.
The one good thign that did happen today was I was able to verify what cable went where and the orientation.
J3 goes to J3
J4 goes to J4
Pin 1 is correctly marked on both ends.
NeXT
Veteran Member
After an hour or so of heating the cable, stretching and massaging it I got one to cleanly crimp on.
One more to go.....
One more to go.....