AtariLeaf Posted February 27, 2013 Share Posted February 27, 2013 I have an XEGS where the Select and Option buttons seem to not be working. I had select working if I pushed down hard enough but even then it sometimes won't work. I tried a little rubbing alcohol and working it through a little hole in the sides of the buttons and pushing it down to work it through but that didn't work. I wonder if I need a contact cleaner or something like deoxit or if its more a matter of replacing the buttons, and if so, where can one find reliable replacements these days? Best? Quote Link to comment Share on other sites More sharing options...
Roydea6 Posted February 27, 2013 Share Posted February 27, 2013 The buttons on the XEGS are above the switches. You will probably need to disassemble the XEGS to get to the switches to clean. Quote Link to comment Share on other sites More sharing options...
AtariLeaf Posted February 27, 2013 Author Share Posted February 27, 2013 You mean disassemble the little black buttons on the board? I can't see a way to do this. Quote Link to comment Share on other sites More sharing options...
mimo Posted February 27, 2013 Share Posted February 27, 2013 They will probably need replacing, to do that you need to de-solder from the underside of the board. Check that they are not working with the case off first. It may be that the big console buttons are broken or bent out of shape and not mating properly with the small tactile switches on the motherboard Quote Link to comment Share on other sites More sharing options...
AtariLeaf Posted February 27, 2013 Author Share Posted February 27, 2013 Well I do have an extra dead XEGS I suppose I could use the buttons from it. But I have no way to know if they work as I can't get that machine to turn on at all. Quote Link to comment Share on other sites More sharing options...
atari8warez Posted February 27, 2013 Share Posted February 27, 2013 Well I do have an extra dead XEGS I suppose I could use the buttons from it. But I have no way to know if they work as I can't get that machine to turn on at all. First thing you should try before starting to desolder the switches is to squirt a little bit of contact cleaner (I myself always use WD-40 and am always happy with the results but I am no longer suggesting using it to anyone as i don't wanna be attacked by the hawks circling around) and let it seep into the switches, if you don't have a contact cleaner, Isopropyl Alcohol will do (which is the main ingredient on most contact cleaners anyway), it will dissolve any oxidization, don't worry if it runs off the switches, it is actually better if it does, so long as the board is not plugged in and turned ON. Wait till it evaporates and re-try the switches, in most cases they will be operational. I doubt that switches need replacement, they are not used as heavily as the keyboard keys. Quote Link to comment Share on other sites More sharing options...
ongikong Posted April 20, 2013 Share Posted April 20, 2013 i have exactly the same problem with my xegs buttons. could you solve it with the cleaning method? Quote Link to comment Share on other sites More sharing options...
atari8warez Posted April 26, 2013 Share Posted April 26, 2013 I'd say the best way to find it out is by trying. After all, you have nothing to loose if it doesn't work. Quote Link to comment Share on other sites More sharing options...
AtariLeaf Posted August 17, 2017 Author Share Posted August 17, 2017 Bumping an old thread that I'd forgotten about but I did try deoxit on the buttons in question. Unfortunately it did nothing and both buttons appear dead. Does Best sell replacement buttons? I looked on the site but I can't seem to find them. It does mention that all parts aren't listed so I should email but does anyone know if they sell these and if so what the price is? Also do the replacements work well? Quote Link to comment Share on other sites More sharing options...
+DrVenkman Posted August 17, 2017 Share Posted August 17, 2017 Bumping an old thread that I'd forgotten about but I did try deoxit on the buttons in question. Unfortunately it did nothing and both buttons appear dead. Does Best sell replacement buttons? I looked on the site but I can't seem to find them. It does mention that all parts aren't listed so I should email but does anyone know if they sell these and if so what the price is? Also do the replacements work well? Do you have a multimeter? I’d check continuity on the switches. It’s possible they aren’t bad at all but that the GTIA is flakey. It reads console switches, unlike the rest of the keyboard which is read by POKEY after going through a matrix of 4052 chips for demuxing. Quote Link to comment Share on other sites More sharing options...
AtariLeaf Posted August 17, 2017 Author Share Posted August 17, 2017 Unfortunately no, but I suppose it's something I should invest in. Are multi-meters expensive? I'd prefer to get one locally but not sure where to turn. If the GTIA is at fault would the other console buttons still work? It just seems two are not working Quote Link to comment Share on other sites More sharing options...
+DrVenkman Posted August 17, 2017 Share Posted August 17, 2017 Unfortunately no, but I suppose it's something I should invest in. Are multi-meters expensive? I'd prefer to get one locally but not sure where to turn. If the GTIA is at fault would the other console buttons still work? It just seems two are not working Multimeters go from as low $8 on eBay, to hundreds of dollars for a high-end model. Perfectly serviceable full-featured units with continuity testing for low-voltage hobbyist work are available for $20 - $30. As for the second question, the answer is "maybe." GTIA is a complicated integrated circuit and it can fail in weird ways. If you already had a multimeter it would be a super-easy thing to check - if the switch works, and if you have continuity all the way from the switch do the GTIA input pins, you'd know it was an issue with the chips. And even if the switches are just dirty, a meter would let you ensure you got them good and clean. Anyway, the advice you've already gotten is good - if you haven't already, you need to disassemble the thing to clean those switches directly, if nothing else. But assuming you have done that, I'd never ever advise someone to desolder and replace parts without a meter to verify it's necessary. Quote Link to comment Share on other sites More sharing options...
AtariLeaf Posted August 17, 2017 Author Share Posted August 17, 2017 Ok thanks sounds like my first order of business is a decent multimeter. Thanks for the advice Doc Quote Link to comment Share on other sites More sharing options...
AtariLeaf Posted August 17, 2017 Author Share Posted August 17, 2017 I know this is cheap and probably entry level but would this work? It's in Canada too which is better for me http://www.ebay.ca/itm/Digital-Voltmeter-Ammeter-Ohmmeter-Multimeter-Volt-AC-DC-Tester-Meter-/222559584542?hash=item33d195c11e:g:bt0AAOSwcj5ZULCM Quote Link to comment Share on other sites More sharing options...
+David_P Posted August 17, 2017 Share Posted August 17, 2017 Or Canadian TIre: http://www.canadiantire.ca/en/pdp/mastercraft-digital-5-function-multimeter-0520060p.html#srp Quote Link to comment Share on other sites More sharing options...
+DrVenkman Posted August 17, 2017 Share Posted August 17, 2017 Either of those will serve for the average hobbyist working with manageable voltages inside vintage computer stuff like our machines - they both do continuity testing ("Diode mode"), which you need to see if switches are working properly. 1 Quote Link to comment Share on other sites More sharing options...
AtariLeaf Posted August 17, 2017 Author Share Posted August 17, 2017 Or Canadian TIre: http://www.canadiantire.ca/en/pdp/mastercraft-digital-5-function-multimeter-0520060p.html#srp Even better, thanks. Just ordered one online and will pick it up tomorrow after work Quote Link to comment Share on other sites More sharing options...
AtariLeaf Posted August 19, 2017 Author Share Posted August 19, 2017 Ok have the multimeter and watched some videos of how to use it. The manual that came with it was useless. I'm guessing I set it to "continuity" which on mine is the bottom most left with the dot and four growing parentheses and then plug the two probes (black in com and red in the middle) turn on the XEGS and touch each side of the switch and listen for a beep? Do I need to test the GTIA as well and listen for beeps and which is the GTIA? I haven't actually had time to drag out the XEGS yet and haven't had time to look the board over so am hoping to try this tonight. Gotta help a friend build a fence today Quote Link to comment Share on other sites More sharing options...
+DrVenkman Posted August 19, 2017 Share Posted August 19, 2017 Basically yes - set the meter to Continuity mode and touch the probes together first. You should hear a beep - that will confirm the meter is working. Then you can get the hang of using the probes by flipping the board over and just looking for trace with two pins soldered into it at different places. Test by placing one probe on each pin and verifiying the current flow. Now that you've got the hang of it, do the same thing with the switch - find the two pins where it's soldered to the board and place the probes. You should hear silence; then press the button. If you hear the beep, the switch is fine. If that's the case, you need to trace the lines back to the GTIA socket (hopefully there's a socket but there may not be ...) and see if you can get continuity all the way back to the chip. If you DO, then the issue is the chip, not the switch. 2 Quote Link to comment Share on other sites More sharing options...
AtariLeaf Posted August 20, 2017 Author Share Posted August 20, 2017 So I did a quick check on the buttons. I'm still not sure which one is the GTIA but when I tested the buttons from underneath the board, I got them to respond as they should. Here's a quick and dirty video of it Quote Link to comment Share on other sites More sharing options...
+DrVenkman Posted August 20, 2017 Share Posted August 20, 2017 So I did a quick check on the buttons. I'm still not sure which one is the GTIA but when I tested the buttons from underneath the board, I got them to respond as they should. Here's a quick and dirty video of it Hard to tell from your video - are you just shorting the pins or are you testing by holding the test leads to the board and pressing the switch? If you're shorting the pins with the test leads and the game responds as it should, then GTIA is fine (it's the one labeled CO14805). You can then clean the switches with Deoxit and test them with the board powered down - that's where the continuity mode of your meter comes in. Put the probe on the two relevant pins, press the button and see if you get continuity. If not, even after cleaning, the switch is bad. Quote Link to comment Share on other sites More sharing options...
AtariLeaf Posted August 21, 2017 Author Share Posted August 21, 2017 With it powered down I don't even get a response from the known good switches. As I understand it, I put the two probes, one each on either side of the solder points on the bottom of the switches, that's what I was doing in the video. Difficult to hold the probes on each side of the pin and press the button but I eventually got it, but none of the switches reacted with a beep when powered down. And I know two of them work. I then tried doing the same thing from the top of the board, again no response even on the known good switches. Am I doing something wrong? I did test a battery I had in my desk drawer and got a beep so I know I'm using the meter right. If you're shorting the pins with the test leads and the game responds as it should, then GTIA is fine If true then is further testing even necessary? Sorry if that's a dumb question. I'm very new to all this. EDIT: I tried touching one probe to a switch and one to the thin metal strip that runs along the front of the motherboard and I got beeps on each switch but that was whether they were pressed or not. Very confused. Quote Link to comment Share on other sites More sharing options...
flashjazzcat Posted August 21, 2017 Share Posted August 21, 2017 I did test a battery I had in my desk drawer and got a beep so I know I'm using the meter right. Ensure you have the meter in the correct mode. It should be in diode mode, since you're testing not for current but continuity. Also, it's best to perform resistance/continuity tests with the power off. Quote Link to comment Share on other sites More sharing options...
AtariLeaf Posted August 21, 2017 Author Share Posted August 21, 2017 Will something bad happen with the power on? I'm still getting nothing on my known working buttons, no beeps Quote Link to comment Share on other sites More sharing options...
+DrVenkman Posted August 21, 2017 Share Posted August 21, 2017 Will something bad happen with the power on? I'm still getting nothing on my known working buttons, no beeps I don't have an XEGS to compare how the switches are wired; post a closeup photo of the board where you're testing and another of the setting you're using on your meter, and maybe people can help figure out what's going on. Quote Link to comment Share on other sites More sharing options...
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