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EvilDragon17

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  1. Heck, yeah, Lynx is the opposite from most oth Ah, yeah, as Lynx is the opposite way from normal systems, this always confuses me Removing Q7 and / or C36 doesn't change anything. I haven't yet connected it to 9V - as for some reason, the official Lynx power supply makes 12V. Is it safe to connect these as well? I have tried a few more things regarding C37 and R68: * When the unit is switched off: When I connect TP17 to Pin 7 of U6 (bypassing C37 and R68), should that switch on the Lynx II? As it does that. * Removing R68 doesn't change anything * Removing C37 stops the unit from switching on. When I shortly connect TP17 to Pin 7 of U6, the unit starts up. Some more measurements: * When the unit is switched OFF, Pin 6 of the Flex PCB connector (POWER ON) has 4.5V, Pin 7 (POWER COM) has 4.95V. * When the unit is switched ON, Pin 6 of the Flex PCB Connector has -0.34V, Pin 7 has 0V. This is the same whether a flex cable is connected or not.
  2. Thanks, that's a very good guide (though I do not have an oscillator at home), but somehow, I'm still at a loss and couldn't figure out what exactly this could be. Okay, here's what I tried: * I made a short circuit between pin 13 and 14 on U6 to prevent the unit from turning on when I connect it to power and was able to measure all U6 voltages. These are all fine. * I checked the values of R69, R73 and R68. They're all fine. * As I modified the unit with a RECOM, I don't have Q8 and some other parts on the board. This mod is NOT responsible for the problem - the problem was already present before and I've added that mod to around 20 Lynx before, so that should be fine. * I can SWITCH OFF the Lynx II either pressing the power button or by connecting PIN 13 with PIN 14 on U6. And it STAYS off. * I can SWITCH ON the Lynx II by connecting PIN 13 with PIN 7 on U6. I CANNOT switch it on using the POWER BUTTON or by connecting Pin 6 with Pin 7 on ribbon connector or by connecting TP17 with TP18 (which basically simulates pressing the Power on-Button. So in a gist: As soon as the Lynx II receives power, Pin 13 is put to HIGH for some reason. Switching it off does work and puts Pin 13 LOW (and it stays LOW), but a power button press does not bring it HIGH again. What part could be responsible for that? It sounds like it should be something really simple, but I cannot grasp it yet.
  3. Okay. True, that's why I usually try to touch the surface of the ceramic cap without applying pressure Not really. R68, the negative side of C37 and R68 are all connected to GND, and that's a straight connection that can easily be seen on the PCB. The anode of C37 is connected to the other side of R68 whereas the other side of C38 is connected to R70. C37 has just been recapped, but the reading also shows 1uF, so that's fine. C38 shows 9,8nF when it's desoldered, so that does look good as well.
  4. Well, but it behaves the same without the flex connected and the works fine in another Lynx II
  5. Well, I replaced it with an untested one from another Lynx II (which was completely dead), but at least I think it would be rare if they both had the same defect. I have a Multimeter here, but I did test it anyways: Connecting Pins 11 and 7 while I connect the power supply keeps it off even when I remove the wire afterwards. And... ... connecting Pin 7 and 13 afterwards powers on the Lynx II. So, spot on with the diagnosis! The question now is to figure out what to replace / check / fix now. C37 is properly connected with C38 and R68. The other end of C38 goes to R70 and Pin 11 of U6. Pin 13 of U6 is connected with TP16 and Q7. Anything I'm missing? Thanks
  6. Hi, I'm having a Lynx II here with a power issue I've not encountered before. As soon as the power supply is connected or batteries are being put in, it switches itself on automatically. It can be switched off - but switching it on does not work again (also not connecting TP17 with TP18, so it's not the flex cable - I also tried the flex cable in another Lynx and the Power On button does work fine). I've done the following: * Replaced U6 * Checked the capacitors and resistors needed for the on / off latch * Disconnected the Flex cable (to make sure it's not a stuck button). * Checked that TP17 and TP18 don't have a short circuit So... anybody have any idea? Why would the Lynx II switch itself on as soon as you give it power and while it can be switched off, it cannot be switched on again...? Thanks in advance for your help
  7. Thanks for your help, I actually figured out what the problem was. It wasn't a failing part, it was a missing trace.... I'll still give some information as it might be helpful for other The pins for the power On button on the flex cable connector are Pins 6 and 7. These are directly connected without any other part inbetween to TP17 and TP18. So connecting TP17 and TP18 effectively simulates pressing the Power ON button. That's a good way to rule out the flex cable. Another helpful hint was: "ON Button Pressed = shorts ribbon pin 6/TP17 to ribbon pin 7/TP18 (about 100 Ohm)" "OFF Button Pressed = shorts ribbon pin 7/TP18 to ribbon pin 14" As pressing OFF did work in my case, we could basically rule out an issue with TP18 / Pin7. Which narrows it down to TP17. We know TP17 is connected directly to the Power ON button - but where else should it be connected? According to the schematics I found here, TP17 should be connected to R68 and C34. And that's what lead me the wrong way: I didn't find any C34 on my Lynx II mainboard. However, you did mention the issue could be C37 - and then I took a look at the mainboard and the schematics linked above. And in fact, it looks like what they call C34 should really be C37. The capacity is correct and it's also connected to ground and R68. So it SHOULD be connected to TP17 as well, if the schematics are correct. Well, it wasn't on my mainboard. So I did add a small wire from TP17 to C37 - and that made the power on button work again. I haven't followed the trace, so I don't know where it broke - but for some reason, it did - and that simple wire fixed the unit. So thanks for pointing me in the correct direction, another Lynx II is now fully restaurated and ready to be played Ah, yes, that was a typo, I missed the K on my multimeter. It is in fact 100K.
  8. First of all, thanks for your help I was just wondering, as TP18 is connected to Pin 13, not to Pin 11, so something might be broken inside U6. Yes, they're all find and R69 is 100 Ohm, so all good there. Well, it can't be the power button as the system doesn't switch on when I connect to TP18 and TP17, which should basically simulate a press of the ON button without the flex cable involved :/
  9. Hi! I'm having a small issue with the Lynx II Power circuit (there are tons of threads about it, but these didn't help me yet...) Okay, I received a Lynx II that didn't work at all. So I gave it a full-refresh with new capacitors and also the 5V Recom Mod (which I did on multiple Lynx and Lynx II as well, so I'm fairly sure the issue doesn't have anything to do with that mod). So, what's not working? Pressing Power ON does not work. What have I done to figure out the culprit? Well, of course, the first thing I usually check in this case is the membrane and any broken traces. The membrane is fine (and works in another Lynx II) and both Pin 6 and 7 go to TP17 and TP18. Manually connecting TP17 and TP18 also does not power on the Lynx II. Replacing Q8 did not fix that. Bridging the pins to check if a cartridge is inserted also doesn't help. What DOES work? I found in a thread on these boards, that connecting Pin 14 and 11 of U6 should also start up the Lynx II. And indeed, that does work! The Lynx II starts and runs without any issues - all buttons work and powering it off does work as well. So, to recap... The power button circuit does not work. Connecting TP17 and TP18 does not start the Lynx II. Connecting Pin 11 and 14 of U6 starts the Lynx II without any issues. It CAN'T be a lot of parts now that could cause this behaviour, I guess. But I don't know which ones this could be. The Zener diode (and most of the other diodes as well as some resistor and Q7) don't even exist anymore because the'yre not needed when you have the Recom Mod. Is there anything besides U6 that could cause that issue? Other idea: Could there be a workaround? Seeing that bridging Pin 11 and Pin 14 makes the unit boot, maybe I can disconnect the On-Switch from the normal connections and directly connect them to Pin 14 and 11? That would only be a worst-case fix though, I'd rather fix what's broken, but I can't find the culprit. Thanks for any help here
  10. Nope, that's MicroUSB. I usually buy power supplies with a USB Port and use an external cable, as that can be used with anything
  11. Don't forget the cable! A cheap, thin USB cable has a higher resistance and causes a voltage loss. The higher the needed power is, the higher the voltage loss. So even 3A power supply won't help if the loss of the cable is too high. The longer and thinner the cable, the more loss. So thin and thick cables should usually work better.
  12. I've had adaptors with 1.5A which worked... and 2A ones that were so cheap they didn't. So it depends on the adaptor - if you have it already at home, it won't hurt to try it.
  13. We're trying to find a cheaper shipping service to get them to console5 right now. No worries, there a still a couple hundred left
  14. Creating a high-voltage (220V / 110V) power supply is almost impossible, as certifications and safety testings cost more than 10k EUR. That's the reason we had the USB idea - I first wanted to simply create a new power supply for the Coleco, but that's almost impossible.
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