Recent content by MichaelFin

  1. M

    STK-0050 replacement for SX-780 and others

    Whoop whoop! Works like a charm. Going to troubleshoot my other board with the collector issues, I think its just the sil pads. But the other module works like a charm! Thanks for helping me out everyone, I appreciate it.
  2. M

    STK-0050 replacement for SX-780 and others

    This seems to be my issue. It would appear I didn't order a shoulder washer and that is causing my issue. I will hopefully find a part laying around otherwise I'll order one. Thank you!
  3. M

    STK-0050 replacement for SX-780 and others

    According to the MJE data sheets the 'tab' is internally connected to the collector so whenever my screw touches the tab (and the screw is touching the Al plate) I get continuity between my collector and the tab. I guess I'm still having issues getting all of my collectors to be free of the Al...
  4. M

    STK-0050 replacement for SX-780 and others

    Good to know. I will try that method on my other Al plate and PCB. Hopefully I will have more success. Thank you for all of the trouble shooting!
  5. M

    STK-0050 replacement for SX-780 and others

    Three of my transistors, Q1,Q2, and Q4, have continuity between ground and their collectors. Is this something I can fix? What is causing this? I sanded my aluminum heat sink and I'm still having the issue. Would the best practice for populating this board be installing the BJTs to the heat...
  6. M

    STK-0050 replacement for SX-780 and others

    Good to know! I will sand my heatsinks and reinstall and check for any grounding of the collectors. Hopefully everything will pass inspection and then my 780 will fire up just fine.
  7. M

    STK-0050 replacement for SX-780 and others

    My pin 1 to 3(+) is 1.111V and my pin 8 to 10(+) is 1.162V when in diode test mode. Do those sound like allowable values? I've always remember diode drops in the range of .5 to .7 or so, seems close to expected from my mind.
  8. M

    STK-0050 replacement for SX-780 and others

    Thanks for those images and that resource! That was how I originally screwed it in. When you say "shoulder" are you talking about the body portion's hole/screw terminal of the TO-220 package? They don't appear damage from when I first tried to mount them. I'll continue to troubleshoot with...
  9. M

    STK-0050 replacement for SX-780 and others

    I used the washers when screwing on the board to the aluminum plate. I placed them above the actual BJT packaging before screwing them in, is that correct? Or were they supposed to be under the BJTs (i.e. touching the thermal insert between the BJT and the aluminum plate). @ info about fuses...
  10. M

    STK-0050 replacement for SX-780 and others

    Noted. I found a thread that seems to confirm the consensus is that the 4A 125V fuse (3-4 node fuse) is associated with the darlington power packs. This makes me think I did something wrong on my PCB populating that caused it. I'm going to remove the heat sink and take some photos of my...
  11. M

    STK-0050 replacement for SX-780 and others

    Q2 is the PNP (MJE15031G) and Q3 is the NPN (MJE15030G). Is that what you mean when you say check the TO-220 placements or are you referencing something other than the PNP/NPN placements being correct (as in, correct board spot). I believe Q5 is installed correctly, the exposed body part is...
  12. M

    STK-0050 replacement for SX-780 and others

    Of course! I have checked continuity between all six pins (wires) going to the board and I have no shorts. I left the leads on the BJTs for now just encase I made a mistake and have to feed them through again. They all have solic connections on the backside of the board, I know it looks like...
  13. M

    STK-0050 replacement for SX-780 and others

    I finished populating my replacement board and mated it with some 22AWG wire and when I went to power it up I blew the fuse between points 3 and 4. I thought I could use the 22AWG just to test the circuit. It seems the recommended wire gauge is 20. Thoughts?
  14. M

    STK-0050 replacement for SX-780 and others

    Thank you so much! Hopefully by the end of next week I'll have soldered them on alright and can test them out. Thank you again, I appreciate it.
  15. M

    STK-0050 replacement for SX-780 and others

    Ah, this makes sense. I understand now. Thank you! Q1:[NJW1302G](http://www.mouser.com/Search/ProductDetail.aspx?R=NJW1302Gvirtualkey58410000virtualkey863-NJW1302G_ Q2...
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