Search results

  1. dneu201

    Project Debut Carbon Evo - motor wont run

    I took a picture of my motor/PSU board. I’m getting 0V at each of the motor wires on the board. I also noticed R9 is missing on my board… anyone know if this could be the culprit.
  2. dneu201

    Project Debut Carbon Evo - motor wont run

    I just recently purchased a $20 Project Debut Carbon Evo. It is missing some parts I need to source but the motor does not spin. So that’s the first issue I need to tackle. I have the US wall wart version that requires a 15 Volt DC wall wart, which wasn’t included. I used an external PSU I had...
  3. dneu201

    2SA1102 And 2sc5577 replacements for Sansui 3900Z

    Sorry. Meant output transistors
  4. dneu201

    2SA1102 And 2sc5577 replacements for Sansui 3900Z

    just ordered those transistors. I ordered an extra amount just in case.
  5. dneu201

    2SA1102 And 2sc5577 replacements for Sansui 3900Z

    Just tested Q12 on one channel and it tested fine. I went ahead and took the good and working original pair of outputs and put them back into one channel and it plays fine even after turning the volume up. it appears my problem was those 1102 outputs.
  6. dneu201

    2SA1102 And 2sc5577 replacements for Sansui 3900Z

    When I open this link it brings me to the home page for some reaso.
  7. dneu201

    2SA1102 And 2sc5577 replacements for Sansui 3900Z

    R29 tests fine
  8. dneu201

    2SA1102 And 2sc5577 replacements for Sansui 3900Z

    I have not pulled the drivers to test them. When I first got the unit, only one output pair was bad. I was able to test the GOOD output pair on both channels with 0 issues and both sides played fine. both channels I biased at 10mv according to the manual (probes on the E legs of the mosfets)...
  9. dneu201

    2SA1102 And 2sc5577 replacements for Sansui 3900Z

    R25 - 100 ohm - both were bad on both channels. I checked and confirmed R24, R26 and R28 were fine.
  10. dneu201

    2SA1102 And 2sc5577 replacements for Sansui 3900Z

    Now that I look closer, the 1104 transistors I received don’t match the picture online or the original 1102 Sankens I had. Both of the new 1104 blew and one of them even cracked somehow and took out a couple resistors.
  11. dneu201

    2SA1102 And 2sc5577 replacements for Sansui 3900Z

    Got them on eBay from this listing . https://www.ebay.com/itm/2-PAIRS-2SA1104-2SC2579-riginal-New-Sanken-Transistor-FREE-US-Shipping-/384083178254?mkcid=16&mkevt=1&_trksid=p2349624.m46890.l49286&mkrid=711-127632-2357-0
  12. dneu201

    2SA1102 And 2sc5577 replacements for Sansui 3900Z

    Hello, needing some help on a Sansui 3900z. I got this unit not working and determined there was an issue with the outputs A1102/2sc5577. I ended up purchasing pairs of A1104/2sc5579’s and after installing and setting the bias the receiver worked fine until I turned the volume up to higher...
  13. dneu201

    Sansui 3900Z - Output Transistor Equivalents

    Saw on Audiokarma someone used these outputs in a 5900z. Would these work? https://www.ebay.com/itm/5-PAIRS-2SA1104-2SC2579-riginal-New-Sanken-Transistor-FREE-US-Shipping-/384083179129?mkcid=16&mkevt=1&_trksid=p2349624.m46890.l49286&mkrid=711-127632-2357-0
  14. dneu201

    Sansui 3900Z - Output Transistor Equivalents

    Hello, I just recently purchased this unit for $40 in non-working condition knowing I would have to fix an issue causing the power fuse to blow instantly. I tracked it down to the left channel output transistors and confirmed both sides work if I move the working outputs to the opposite channel...
  15. dneu201

    Marantz Model 30 Vintage receiver - Noisy with streaming

    Not sure why this did it, but changing the included wall wart that came with the Bluetooth dongle to an Apple IPad 5V adapter did the trick. The Bluetooth adapter came with a separate usb power cable so I used it with the Apple iPad plug and the noise went away. Still not sure about the...
  16. dneu201

    Marantz Model 30 Vintage receiver - Noisy with streaming

    I have a Marantz Model 30 vintage receiver I rebuilt. Everything works great, except when I have a Bluetooth dongle or my Bluesound node hooked up to it there is noise on the phono. Both of those devices add buzzing, whirring and whizzing noise into the phono and especially in the right...
  17. dneu201

    Who is the guy here running the big Heil on top of skinny cab?

    Messaged Ed but waiting on a response. Is anyone that owns a pair of these speakers able to check their Heils and let me know their impedance?
  18. dneu201

    Who is the guy here running the big Heil on top of skinny cab?

    I am revising this thread as I have a question about these. Did Ed design the crossover to use 8 ohm or 4 ohm Heil AMTs? I was given a pair of ESS AMT after purchasing an amp from the owner. After testing the AMTs I realized one was 4 ohm and other 8 ohm. He said he has replaced the diaphragms...
  19. dneu201

    Pioneer SX-980 DC Offset Unstable

    Yea. I apologize I did not check power supply voltages first. When the tech had told me it was an issue with the left channel, I figured it was a transistor problem and went directly to the amp boards. I think while I still have the unit I will replace the 2sd712 as I have some replacement...
  20. dneu201

    Pioneer SX-980 DC Offset Unstable

    Cold solder joints…. Geeeze. the two 2sd712 and the 2SB682 had cold joints. i touched them up and was able to set dc offset right at 0mv and bias to 30mv. These get pretty hot to the touch so I’m sure over time those joints wore away. I cannot believe that was the issue…
  21. dneu201

    Pioneer SX-980 DC Offset Unstable

    Think I may have discovered my issue. I read a forum with someone that mentioned this issue could be caused by the Power Supply. I did some voltage checks and noticed some of the voltages were WAY off around test point 23, 22, 20, and 19.... See below on what I measured vs what the schematic...
  22. dneu201

    Pioneer SX-980 DC Offset Unstable

    The offset never settles not even for a second. It just continues changing erratically. I can attempt to set it at 0 but it will range between 0 and 60mv. I was checking offset at the speaker outputs at first, but comparing it to pins 9 and 10 I get the same results as far as changing offset...
  23. dneu201

    Pioneer SX-980 DC Offset Unstable

    Another update. I took the matched pair of KSA992 I had and put it on the right board to see if it fixed the issue. before installing the matched pair I tested both sections of the original differential and it tested within spec. I went ahead and soldered in the matched pair and same...
Back
Top Bottom