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mickcris

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  1. It has come to my attention that there is a mistake on the 7374 PCB. The 4th output is unused and is tied to ground while it should be floating. This is causing the IC to run hotter than normal. I would think the risk is fairly low as some of these have been in use for almost 2 years now. My guess would be that it running a bit hotter will cause the amp to wear out faster. Its also a possibility that the 4th channel could just go out and the chip return to normal temps. The temp its running at is still below the continuous operation long term reliability max temp. Having said that, I have not had any reports of any of them failing yet but you may want to either modify the board or discontinue using it. I tested one and after running for an hour, I measured it with my Fluke 87 meter and its running at 65 °C. With the 4th output floating the temp is 30°C. Per the data sheet: Maximum junction temperature, continuous operation, long-term reliability is +125 °C You can fix this by lifting that leg. Here is pic with an arrow pointing to the pin that needs lifted https://imgur.com/a/cMeWI3l I found it easiest to just de-solder that side of the IC, lift/break off the leg, then re solder that side down. If you purchased one of these and would like me to lift the pin for you or give you a refund, send me a message and I will get back to you. I may need proof that you purchased it from me. I will only refund ones that I sold that I had soldered. If you bought one from console5 though i will lift the pin on it. If you want me to lift the pin, send me the pcb(s) along with a piece of paper with a return address and you email. I will lift the pin and then send it back. If you want a refund, send me the pcb(s) along with a piece of paper with your paypal email address. I will then send $20 to your paypal account per amp.
  2. since im no longer selling these, i shared the files if anyone wants to build there own https://oshpark.com/profiles/mickcris
  3. that cable is wired incorrectly. like most aftermarket genesis 2 composite cables https://forums.terraonion.com/viewtopic.php?f=11&t=9
  4. You would need a Genesis 2 cable. they said they added a 21 or 22 ohm resistor inside to add to the 75 ohm resistor in the cable to bring the voltage down. Since they screwed up the design, it was pretty much the easiest way for them to "fix" it. If you want a proper built amp for RGB, you would need to modify your console. If you dont care that the output impedance isn't right, then you can use the output from the Super SD system. But you probably wont notice the difference with your eyes.
  5. I have updated the amp with output resistor values closer to the ideal values of 86 ohm with a 586 ohm to ground. The ideal values can only be done with 4 resistors so have changed to the closest I could get it with 2. Now using an 86.6 ohm resistor with a 604 ohm resistor to ground. Both resistors are 0.1% tolerance. See the math below:
  6. That is a pic of the coleco chameleon prototype.
  7. Who doesnt want to hook an snezz cable to their jag
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