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DistantStar001

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About DistantStar001

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  1. Thanks!!! Looks like a noisy PSU. Kind of a shame, though. It's the original. Maybe replacing the filter cap will help matters. In the interim, I spliced a din connector onto an old laptop charger. It seems to have cleaned the image up considerably. Although I will probably want to recap the internal regulator when I get a chance.
  2. I replaced the regulator! So now my //c is back and running!!! For those who might be curious, the short between pins 11 and 12 is normal as it is present on the working regulator as well. I still haven't given up on the original. But now I have a working example as a guide to diagnose whatever the defective component is. So far, I've replaced the DUV26 Transistor at Q2, the HA17339 IC, all of the electrolytic compactors, and the regulator abled IC2 (not sure why it was abled that way). I've also checked all of the diodes in and out of circuit. Basically, I've been poking blind. Hopefully the working one will point me in the right direction. I'll post again if I figure it out. An additional question: I noticed that the text has a noticeable rainbow-bleed on the screen. Admittedly I'm using an old SAHRP CRT TV from the 90's, but its a bit more severe than it should be. I remember a similar issue just before the old regulator died. It took several years. And at first, I thought it was just the natural result of having been in storage for more than a decade. But it got really bad the day it died. Then the video started to cut out, and it just shut off and wouldn't power on again. So I'm a little concerned about this. Any suggestions on how to keep my beloved //c healthy would be appreciated.
  3. Just out of curiosity, Does anyone know a US seller who carries a ready-made Amiga 500 compatible Gotek? I've been looking into it, and near as I can tell, it's actually more expensive to piece these together (Gotek, OLED, and mounting bracket) than it is to simply get the ready made one. Or at least it would if I were in Germany. In the US, shipping makes it a bit of a wash. But before I go about importing one from the other side of the world, maybe someone could point me to a more local source? Or atleast on the same continent? Also, just to reiterate, as I am really new to the Amiga, and I don't think I say this often enough... Thank you all so much for all the help and suggestions given to me so far. You've all been very helpful and supportive!!! 🙂
  4. So the good news is that I was able to determine that the HA17339 has failed and I was able to install a replacement. However, it didn't solved anything. The lines that connect pins 11 and 12 are still shorted elsewhere on the board as well, and I still don't know if this is normal. All I do know is that they're not supposed to be on the chip. It also occurred to me that I forgot to mention which regulator I'm working on. It's an Astec AA 7343A. Hopefully that will help. I've been looking everywhere for a schematic for this. But so far, I haven't had any luck. If anyone has this (or even just a layout of the traces on the PCB) it would be extremely helpful.
  5. Unfortunately, I already have this. While, it was very helpful in identifying some components, my //c is a little newer. So the schematics don't exactly match. From what I can tell, the IC in question isn't even present in the regulator documented. Thanks though. Even if it didn't help with the problem at hand, this is a terrific manual and very informative! Honestly, every //c owner should give it a look over. 🙂
  6. A while ago, my trusty //c decided to be a little less than trusty when it burned out both the fuses on the motherboard and in the power supply. I've since replaced the fuses and managed to trace part of the fault to the DUV26 Transistor at Q2 on the voltage regulator board, so I replaced that too. Now it no longer burns its fuses (good news!) Unfortunately, I'm still not getting a 5v output from the regulator. I've removed and tested all of the capacitors. The all tested good and showed no signs of bulging or leaking, so I put them back and continued probing. That's when I came across something odd. The HA17339 IC is grounded on pin 11. I looked up the data-sheet and pinout, and from what I can see pin 12 should be the only ground. 11 does have the expected continuity (with resistance) with + on 11 to - on 13 (but not the reverse), as well as from pin 10, with + on 11 and - on 10 (again not in reverse), which seems to correspond to the data-sheet. However, the sheet makes no mention of 11 to ground. Is this normal? Or should I be replacing this IC? Also are there any other points of failure that I should be looking for? As always any assistance is appreciated. 🙂
  7. Good Point! So I looked elsewhere. Disassembled the whole thing, and tested the board, and it came back to life! So I reassembled it, testing power as I added back components. Long story short, I discovered that the issue is in the floppy drive. The TA774P is blown. Must have been that popping sound I heard. Not sure why it went though. I figure it shouldn't be too hard to replace, provided they're still in production. In the interim, that Gotek is looking better and better! Thanks for this! I didn't manage to get it out (probably being overly cautious with it), but I did manage to rock it a bit in the socket. Now the glitching is gone!
  8. You're right. The +12 and -12 volt lines are shorted to ground on the board. Removing the keyboard (and shield) didn't help, but the connector looked to be offset by one pin. I didn't mess with the Floppy connector so that should still be fine. I started testing any component that looked to connect power to ground and found that the component circled in the image (at LF1) is shorted, but not the component below it. I'm still probing the board, but this has me wondering if this might be my issue? Forgot to mention that this is an issue 5 board.
  9. Thank you!!!! CAS2Audio made all the difference! I've managed to load several cas files through it and even record to real tapes with my TI Recorder!!! Off topic, but do you think it would work for a TRS-80 Model III?
  10. Thank You! Spy vs Spy loaded perfectly (on its second try). So at least I know this thing is working! I would still like to be able to convert .cas files, but this is a very promising start!
  11. Any recommended software for this? Or an alternative to TapDance? I tried both cas2wav and a8cas, but Windows 10 won't let me use the first, and the second just crashes. I haven't been able to get them to work through Wine either.
  12. So, I'm actually very frustrated right now, as this may have become a much bigger repair job. I tried reseating some of the socketed IC's to see if that might clear up the graphical glitching. Instead, I got an unstable black screen. By that point, I had removed the keyboard but the drive was still seeking a disk. I reinstalled the keyboard and tried again. This time, Was greeted by a popping noise and no power from the supply. I've been using a standard PC PSU for this as I was under the impression that they were safe (at least as a temporary solution) as long as the voltages are correct and you don't mess up the wiring. I didn't. I checked the voltages with a multimeter and have a visual aid that is color-coded to endure I get it right. I'm always a little paranoid when it comes to Commodore computers and their power supplies (been 'burned' by too many c64's not to be). I've tried two other similar PSU's since (I have no directional hearing, so it seemed the best way to find out where the popping cam from), and while both showed correct voltage before I hooked them up to the Amiga, neither would power on after. In fact, none of them would give any voltage for some time after the Amiga was disconnected. They've all since returned to working condition. I can only guess that there's a short somewhere on the Amiga that's triggering a safety in the PSU's. I didn't pull any of the IC's from their sockets, and I didn't do them all. Just the ROM's and the CIA's. Each chip was gently lifted a bit before pressing them back in. I didn't mess with the CPU as it's rather large, and I figured that if that were the culprit, the machine wouldn't boot at all. Also, I haven't messed with the Angus chip as I don't have the proper tool to remove it at the moment (I've heard the horror stories of cracked sockets). All others are soldered, so there's not much I can do with them at the moment. I've repeatedly checked the board for signs of damage but so far I haven't found anything. I've also removed the RAM expansion with no effect. I know something went wrong. Any ideas as to what?
  13. I've tried that. Sadly, no luck so far. The thing is, the leader seems to make no difference when I reload the BASIC test tape?
  14. Unfortunately, you're right. Only the cost reduced NTSC boards can be converted. The PAL two-prongs have an additional IC between the video cage and the cartridge port that isn't present on the NTSC. Sadly, I don't have an ePROM programer, so I'm stuck looking for the original ROMs at the moment. Good News on that front. I found all of these! It's only the ROMs (and a case) that I need. Then it's a fully functional VIC-20! 🙂
  15. Extracted Audio 01.aiff Hopefully this works. The load method used was Option-Start. The file was Frogger recorded to an actual tape using my TI Program recorder off of TapDancer on an ASUS MeMo tablet. It gave a boot error and then went into self-test.
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