morelenmir Posted March 6, 2016 Share Posted March 6, 2016 The socket attached to the motherboard on XL and XE machines is a sprung, single-wipe friction design and I think a real weakness. In the course of modification or refurbishment one by necessity must insert and retract the keyboard ribbon from it many, many times. It does not take long before the ends of the cable have become bent and twisted which leads to a poor and intermittent connection. Worse still the actual contacts themselves are fairly rapidly worn away. Some replacement membranes are advertized as extra-long so the frayed ends can be trimmed back to a fresh edge. However this seems at best a partial solution and aproaching the problem from the wrong end. Many modern pieces of electronics that use a ribbon cable do not attach by spring friction alone. Often a friction latch is used which clicks open and lets the cable pull completely free or in turns locks closed tightly around it. In either case the wear on the ribbon is greatly reduced or eliminated. I wonder if there are any plugs of that design which could replace the very basic and dangerous one native to the motherboard? Indeed, going a little further I wonder if there is not a better solution altogether, something along the lines of the IDE-style - is it 'Harting' - plugs and sockets? I am quite surprized a mod for this had not appeared already to be honest! 1 Quote Link to comment Share on other sites More sharing options...
flashjazzcat Posted March 6, 2016 Share Posted March 6, 2016 You mean IDC connectors? I suppose there's no reason you couldn't modify at least the XL connector to use some sort of single-row IDC, a bit like the connector on the 800 and 1200XL. Much more durable than anything which followed. Tricky with the XE (and the metal-backed XL keyboards) since the ribbon is actually part of the mylar sheet. 1 Quote Link to comment Share on other sites More sharing options...
Joey Z Posted March 6, 2016 Share Posted March 6, 2016 The socket attached to the motherboard on XL and XE machines is a sprung, single-wipe friction design and I think a real weakness. In the course of modification or refurbishment one by necessity must insert and retract the keyboard ribbon from it many, many times. It does not take long before the ends of the cable have become bent and twisted which leads to a poor and intermittent connection. Worse still the actual contacts themselves are fairly rapidly worn away. Some replacement membranes are advertized as extra-long so the frayed ends can be trimmed back to a fresh edge. However this seems at best a partial solution and aproaching the problem from the wrong end. Many modern pieces of electronics that use a ribbon cable do not attach by spring friction alone. Often a friction latch is used which clicks open and lets the cable pull completely free or in turns locks closed tightly around it. In either case the wear on the ribbon is greatly reduced or eliminated. I wonder if there are any plugs of that design which could replace the very basic and dangerous one native to the motherboard? Indeed, going a little further I wonder if there is not a better solution altogether, something along the lines of the IDE-style - is it 'Harting' - plugs and sockets? I am quite surprized a mod for this had not appeared already to be honest! I have seen ZIF connectors for this in IBM products for use with their keyboards, so they *do* exist, I just don't know what to search for. 1 Quote Link to comment Share on other sites More sharing options...
RodLightning Posted March 6, 2016 Share Posted March 6, 2016 If someone with the skill, means, what have you, could create a backplane type adapter as found in early versions of the 600XL, it would certainly be useful to those of us who are opening and removing the keyboard. The last order I made from Best Electronics, Brad said stock was running low on the XL/XE pinch connectors, and the little 600XL right angle boards were rare enough that he didn't want to sell (or probably just find) the ones he had. Finding the little pinch connector is probably the biggest issue to building anything better. Harvesting them from dead Ataris doesn't seem very appealing or easy, to me at least. The clear mylar film version of the XL keyboard is the worst thing, IMHO that Atari ever produced. I have had some limited success repairing the contacts with conductive paint, but as the OP stated, that does nothing to protect the mylar from bending. Something to permanently clamp onto the film edge would be almost a godsend. I have always liked the feel of XL stackpole keyboards best in spite of their cheap construction. 1 Quote Link to comment Share on other sites More sharing options...
morelenmir Posted March 6, 2016 Author Share Posted March 6, 2016 I have seen ZIF connectors for this in IBM products for use with their keyboards, so they *do* exist, I just don't know what to search for. That is exactly the problem I experienced when this thought struck me and I did some searching earlier. Every variation of '24 contact ribbon connector clip latch' just turned up those IDC ones that FJC mentioned. If someone with the skill, means, what have you, could create a backplane type adapter as found in early versions of the 600XL, it would certainly be useful to those of us who are opening and removing the keyboard. The last order I made from Best Electronics, Brad said stock was running low on the XL/XE pinch connectors, and the little 600XL right angle boards were rare enough that he didn't want to sell (or probably just find) the ones he had. Finding the little pinch connector is probably the biggest issue to building anything better. Harvesting them from dead Ataris doesn't seem very appealing or easy, to me at least. 600XLkbAdapter.jpg The clear mylar film version of the XL keyboard is the worst thing, IMHO that Atari ever produced. I have had some limited success repairing the contacts with conductive paint, but as the OP stated, that does nothing to protect the mylar from bending. Something to permanently clamp onto the film edge would be almost a godsend. I have always liked the feel of XL stackpole keyboards best in spite of their cheap construction. It really would!!! That is one of the reasons I liked the sound of the recent project to mod the POKEY chip so it would accept input from a PS2 keyboard. Obviously you'd get a better range of keyboards then, but also be able to assemble and dismantle the thing as often as you need to without grinding your way through the metal contacts on the mylar. 1 Quote Link to comment Share on other sites More sharing options...
Joey Z Posted March 6, 2016 Share Posted March 6, 2016 (edited) I managed to find .1" pitch ZIF connectors, but none in 24 pin sizes, and in 24 pin sizes, nothing that would really be an improvement over the current connector most likely. Even then, minimum order on digikey was, I think, 250 at roughly $2 each, so unless there is demand for a good chunk of 250, it doesn't sound worth it to buy any of those... On the other hand, there are 'in-line' connectors which would allow you to basically clamp a connector onto the atari mylar, permanently, which would make it into a .1" pitch set of header pins (female or male). I don't know if there would be clearance for the whole connector in an XL though, unless you got some kind of 45 degree angle header... http://www.digikey.com/product-detail/en/amphenol-fci/65801-024LF/609-3511-ND/1528463 Of course, the issue with the above part is that it's not the ink termination version, so really the part you need is this: http://www.digikey.com/product-detail/en/amphenol-fci/65801-124LF/65801-124LF-ND/1527424 as usual, the part you need is non-stock... Edited March 6, 2016 by Joey Z Quote Link to comment Share on other sites More sharing options...
flashjazzcat Posted March 6, 2016 Share Posted March 6, 2016 Having a hard time trying to find one of these with 24 connections: The springy connector on an 800XL or 600XL motherboard could be replaced with a 24 way male header a la the 1200XL if the AWC/Alps keyboard ribbon was replaced by a cable which terminated with the above connector. Quote Link to comment Share on other sites More sharing options...
morelenmir Posted March 8, 2016 Author Share Posted March 8, 2016 I like the idea of turning the ribbon in to a male pin-header, that would be a huge improvement over the current system. I actually have right-angle strip of I think 30 female connectors, but I do not know if the pitch would match. Quote Link to comment Share on other sites More sharing options...
Rybags Posted March 8, 2016 Share Posted March 8, 2016 Alternative - a daughterboard which houses the multiplexor ICs like XEGS, attaches somewhere to the keyboard. Another daughterboard with alternative interface which plugs to where multiplexor ICs were on the motherboard. Problem is, cost and it probably won't fit very well. Not sure on the pin count but I don't think you can get away with anything under 12. Quote Link to comment Share on other sites More sharing options...
Panther Posted March 26, 2016 Share Posted March 26, 2016 Having a hard time trying to find one of these with 24 connections: Capture.PNG I couldn't find one either, so I'm going to try using two of these on each side as well. It's certainly more work and not as clean as having a ribbon cable, but I think this will do. https://www.jameco.com/webapp/wcs/stores/servlet/ProductDisplay?langId=-1&storeId=10001&catalogId=10001&productId=944917 I'd acquired an 800XL where someone had replaced the keyboard cable and connectors in the most gruesome scene imaginable. Quote Link to comment Share on other sites More sharing options...
BillC Posted March 26, 2016 Share Posted March 26, 2016 There is a flex cable connector available that adapts to a standard PCB header post connection, similar to a harting connector but for flex cable. http://www.digikey.com/product-detail/en/2-487769-2/A113195-ND/2294486?WT.z_cid=sp_8004_20120425_buynow&site=us&csp=WT.z_cid%3Dsp_8004_20120425_buynow%26TE_cid%3D8004-1459026299399 Quote Link to comment Share on other sites More sharing options...
Panther Posted March 26, 2016 Share Posted March 26, 2016 (edited) I dug around a bit and found this: http://www.digikey.com/product-detail/en/te-connectivity-amp-connectors/A9BBA-2508E/A9BBA-2508E-ND/470596 One pin more than needed, but it's ready to go! Edit: Oops, this is 0.05" pitch, not 0.1"! Continuing search... Edited March 26, 2016 by Panther Quote Link to comment Share on other sites More sharing options...
Panther Posted March 26, 2016 Share Posted March 26, 2016 Grrrr...this would probably be ideal... http://www.digikey.com/product-detail/en/aries-electronics/24-009-172/24-009-172-ND/4164567 Non-stock, need to order 10! Okay, how many people out there can use a new 800XL keyboard cable? Quote Link to comment Share on other sites More sharing options...
Joey Z Posted March 26, 2016 Share Posted March 26, 2016 Grrrr...this would probably be ideal... http://www.digikey.com/product-detail/en/aries-electronics/24-009-172/24-009-172-ND/4164567 Non-stock, need to order 10! Okay, how many people out there can use a new 800XL keyboard cable? not sure how that helps. Quote Link to comment Share on other sites More sharing options...
flashjazzcat Posted April 27, 2016 Share Posted April 27, 2016 Did anyone manage to source a replacement flex ribbon exactly compatible with the original? I've been refurbishing a few of my XL keyboards and the most common problem is breaks along the ribbon cable. Ideally I'd just like to swap them out for new ones. 1 Quote Link to comment Share on other sites More sharing options...
flashjazzcat Posted July 10, 2017 Share Posted July 10, 2017 Anyone manage to find a replacement part as per the OP? Got a 600XL here with a break on the 5V pin of the motherboard keyboard ribbon socket. Quote Link to comment Share on other sites More sharing options...
Ely Posted July 10, 2017 Share Posted July 10, 2017 I'd love a better connector as my keyboard is less than reliable when stick that ribbon cable in. As an aside, can I literally just slice a section of the ribbon off in the hope it improves the connection? Quote Link to comment Share on other sites More sharing options...
AHA Posted July 19, 2017 Share Posted July 19, 2017 (edited) had somthing to say, made on sence.... Edited July 19, 2017 by AHA Quote Link to comment Share on other sites More sharing options...
Kyle22 Posted July 21, 2017 Share Posted July 21, 2017 Cut as little as possible and do it straight. You only need to fix the tattered end. Don't make it too short. Use a pencil eraser to shine it up a little as well. Quote Link to comment Share on other sites More sharing options...
Ely Posted July 22, 2017 Share Posted July 22, 2017 Thanks, I'll give it a try. Quote Link to comment Share on other sites More sharing options...
+KlasO Posted October 13, 2019 Share Posted October 13, 2019 Hello everyone, While trying to fix a ribbon cable on an ALPS keyboard in an 800XL, I killed it instead. A couple of the connectors broke off, and unfortunately have nothing to connect to anymore. I cut the bad part off (and the cut is in the white area), but the connectors are too well embedded and do not connect. I don't want to slaughter another good 800XL, and although I may order a replacement keyboard somewhere, I thought I'd try either fixing the cable or replacing it. Also, I am tempted to connect e.g. a pin header to the connector on the motherboard to allow disconnecting and reconnecting the cable w/o breaking it again. Is there a kind soul out there who could give some advice? Quote Link to comment Share on other sites More sharing options...
manterola Posted October 13, 2019 Share Posted October 13, 2019 (edited) You can replace that ribbon cable. I guess the other size is soldered to the pcb of the keyboard, so your version at least includes pcb. Then you have to replace the connector in the motherboard as well, for something easy to source, like pin headers. But first I would try if possible, to strip the insulation from the original ribbon to see if you can make something similar to the original ribbon end. Edited October 13, 2019 by manterola 1 Quote Link to comment Share on other sites More sharing options...
+KlasO Posted October 13, 2019 Share Posted October 13, 2019 Thanks, the cable is soldered to the pcb. I am unsure how to strip the insultation, it is laminated and my first attempt att prying the layers apart did not work. I stopped before I did any more damage :). Quote Link to comment Share on other sites More sharing options...
Sugarland Posted October 13, 2019 Share Posted October 13, 2019 What do you use to try to strip the insulation to make the new connector? How about a razor blade? I too have an alps that needs the same repair. I'm interested in your progress. I believe FJC replaces the cable and installs a new paired mobo connector, as a standard practice. Quote Link to comment Share on other sites More sharing options...
+KlasO Posted October 14, 2019 Share Posted October 14, 2019 17 hours ago, Sugarland said: What do you use to try to strip the insulation to make the new connector? How about a razor blade? I too have an alps that needs the same repair. I'm interested in your progress. I believe FJC replaces the cable and installs a new paired mobo connector, as a standard practice. Tried with a scalpel but thought I’d seek advice before going ahead. I lean towards replacing the cable with DuPont connectors and a pin header on the pcb. Quote Link to comment Share on other sites More sharing options...
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