JDW Posted January 12 Report Share Posted January 12 There are times when you want to make a very long, custom cable so as to pull the SE/30 motherboard outside the chassis for easier testing while still being able to power up the machine. Until now I've been soldering wires onto testing points and pulling those wires outside the chassis, but that is fiddly, time-consuming, and prone to accidental shorts. Rather than mod an existing cable by making it longer, it's better to create a new cable. Surely someone here has done this before. If so, could you please provide the connector part number (or exact web page on Mouser or Digikey) as well as the part number for the metal terminals? I am talking about the cable which connects the SE/30 Analog Board to the Motherboard: Thanks! Quote Link to post Share on other sites
ymk Posted January 12 Report Share Posted January 12 (edited) Amphenol 10127820-1422LF mates with the cable. The pins in the cable should be either 10134170 or 10127817. Edited January 12 by ymk Quote Link to post Share on other sites
JDW Posted January 12 Author Report Share Posted January 12 @ymk Thank you! More specifically... For those wanting to make a cable that merely EXTENDS the stock SE/30 cable, you will need 1pc of the Female connector here (which has pins already inside): https://www.amphenol-icc.com/minitek-pwr-4-2-101278201422lf.html And then you will need 1pc of the Male connector here: https://www.amphenol-icc.com/minitek-pwr-4-2-1012781514lf.html And for use with the Male connector you will need 14pcs of these terminals: https://www.amphenol-icc.com/minitek-pwr-4-2-hcc-101341702220lf.html — — — — However, for those wanting to just make one long cable, which is probably best since you can then use brand new 18AWG wire for the entire length of the cable and lessen the likelihood of connectivity issues, then you need 2pcs of the Male connector: https://www.amphenol-icc.com/minitek-pwr-4-2-1012781514lf.html And you will need 28pcs of the terminals: https://www.amphenol-icc.com/minitek-pwr-4-2-hcc-101341702220lf.html Consider how long you need the cable, then multiple that length by 14 to get the total length of wire you will need, assuming you will use the same color wire for all the wires. Quote Link to post Share on other sites
JDW Posted January 12 Author Report Share Posted January 12 As to the best replacement wire, there's a tradeoff between the lowest resistance and wire flexibility. As much as I'd love to use 16AWG wire, it won't fit the terminals, so we need to stick to 18AWG. See page 3 of the chart below for 18AWG wire. As you can see, the lowest resistance wire shown there has 19 strands of size 30 wire that is Concentric (as shown in the image below). The higher the number of strands, the more flexible the wire but the higher the wire resistance. https://philatron.com/pdf/wire-strand-construction-charts.pdf Insulation thickness is another important consideration. According to the document below, the insulation DIAMETER should be no more than 3.10mm (for 18AWG wire): https://cdn.amphenol-icc.com/media/wysiwyg/files/documentation/gs-12-1377.pdf Here's 19x30 stranded 18AWG wire on Mouser: https://www.mouser.com/Wire-Cable/Hook-up-Wire/_/N-5ggsZ1yzvvqxZgjdhub?P=1yx79kqZ1z0vstf&Keyword=wire&FS=True This document talks about coatings of individual strands: https://www.anixter.com/content/dam/Anixter/Wire Wisdom/12T0024X00-Anixter-WW-Conductor-Coatings-W&C-EN-US.pdf Quote Link to post Share on other sites
aeberbach Posted January 12 Report Share Posted January 12 Do you have a crimper? It’s a really important part of the experience, I bought one recently after folding down the tabs with needle nose pliers for years. You don’t have to spend $900 on a real Molex-branded one of course but you must have one! Quote Link to post Share on other sites
JDW Posted January 12 Author Report Share Posted January 12 2 hours ago, aeberbach said: Do you have a crimper? It’s a really important part of the experience, I bought one recently after folding down the tabs with needle nose pliers for years. You don’t have to spend $900 on a real Molex-branded one of course but you must have one! I do not have one of those over-price crimpers which are made specifically for particular terminals. I have a cheaper, general use crimper that I simply take care in using. The dedicated crimpers are better, but I don't do enough crimping to justify the sky high cost. Quote Link to post Share on other sites
LaPorta Posted January 12 Report Share Posted January 12 I did this exact thing a few months back. Here is the male part number on Mouser: https://www.mouser.com/ProductDetail/538-39-01-2145/ These should be the pins: https://www.mouser.com/ProductDetail/538-02-09-5106/ I duplicated these and the other analog to loogic board and CRT connectors for my test stand: Quote Link to post Share on other sites
aeberbach Posted January 12 Report Share Posted January 12 I did make a thing for my own use that requires a Mean Well PT65B supply - it might not be so useful unless you are doing something to replace the original video out, but I'm happy to send STL files if anyone wants to print this thing. It's three parts - mainboard is just within the print capacity of a Prusa MK3S and power supply component is in two parts to avoid the need for supports while printing. Quote Link to post Share on other sites
elemenoh Posted January 12 Report Share Posted January 12 I just use a standard ATX extension cable. Cheap and ready to use from Amazon. It's wider than the connector on the compact Macs, but still mates with it and is pin compatible. https://www.amazon.com/gp/product/B07VN3DRFW/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1 Quote Link to post Share on other sites
ttb Posted January 14 Report Share Posted January 14 The standard ATX extension works great until you have to deal with one of the socketed logic boards. They have a capacitor next to the power connector that blocks the overhanging part of the connector. Unless folks have figured out a clever workaround I’m not aware of. For crimping the pins, I used an Engineer PA-20. It doesn’t do a good job with the strain relief crimp but made perfect crimps on the conductors. Since you’re in Japan @JDW I imagine you can find one for not too much. Quote Link to post Share on other sites
Chopsticks Posted January 14 Report Share Posted January 14 2 hours ago, ttb said: The standard ATX extension works great until you have to deal with one of the socketed logic boards. They have a capacitor next to the power connector that blocks the overhanging part of the connector. Unless folks have figured out a clever workaround I’m not aware of. For crimping the pins, I used an Engineer PA-20. It doesn’t do a good job with the strain relief crimp but made perfect crimps on the conductors. Since you’re in Japan @JDW I imagine you can find one for not too much. clever work around is to just cut off the extra/unused part of the connector and just file it down if aesthetics are important to the user. buying a atx extender cable is likely cheaper/easier then the min order for free shipping for the parts from places like digikey/mouser Quote Link to post Share on other sites
ttb Posted January 14 Report Share Posted January 14 Haha, of course I guess the only real reason to build one is if you want it to be long and/or thicker gauge. Quote Link to post Share on other sites
Chopsticks Posted January 14 Report Share Posted January 14 very true, I haven't tested max length myself but I imagine that after a point the the video delay would shift the screen off to the right if you used to long a cable.. Quote Link to post Share on other sites
LaPorta Posted January 14 Report Share Posted January 14 My cable is probably 2-3 feet long and narrow gauge wire with no issues. Just for reference Quote Link to post Share on other sites
Chopsticks Posted January 14 Report Share Posted January 14 2 hours ago, LaPorta said: My cable is probably 2-3 feet long and narrow gauge wire with no issues. Just for reference good to know, thanks Quote Link to post Share on other sites
JDW Posted January 14 Author Report Share Posted January 14 Actually, the real reason to build a cable rather than merely EXTEND the stock cable is if your stock cable has corroded contacts and aging wires that show higher than normal resistance, which I have seen on my own SE/30's. The end result of a lackluster stock cable is lower than expected voltage when measured at the motherboard under full load. Building a brand new cable exactly the length you need, leading from the analog board to the mother board (without using the stock cable at all) benefits from brand new wires and connector terminals. You get the lowest resistance connections that are known good (assuming crimping is correct), and that can help one diagnose a board by eliminating the cable as the reason for faults in the system. Also, the more connectors you add, the more resistivity and potential for faults. So while using an ATX cable may be the easiest solution, building a cable (with 18AWG wire) is arguably the best solution. Quote Link to post Share on other sites
JohnWorkman Posted Sunday at 04:16 PM Report Share Posted Sunday at 04:16 PM To make a longer version of the silly short cable of the SE/30 (and likely SE) that goes between the motherboard and the analog board, these are the molex connector parts. You can find these are on Digikey, Mouser, etc. To make the cable, you want the Receptacle and the Receptacle Pins. I've included the other parts too since it's pretty easy to damage the header connector on the motherboard with hot air when recapping. Also, you'll need a crimper. You cannot do this properly with pliers. I used this one and it worked decently and is less than $25: https://www.amazon.com/gp/product/B00OMMZ502/ Receptacle: https://www.molex.com/molex/products/part-detail/crimp_housings/0039012140 Receptacle Pins: https://www.molex.com/molex/products/part-detail/crimp_terminals/0039000039 Plug: https://www.molex.com/molex/products/part-detail/crimp_housings/0039013143 Plug Pins: https://www.molex.com/molex/products/part-detail/crimp_terminals/0039000041 Header: https://www.molex.com/molex/products/part-detail/pcb_headers/0039281143 Quote Link to post Share on other sites
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