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About cspirou

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  1. Balanced to unbalanced board

    Thanks @luvdunhill! I'm using the buffer with the ubal/bal board which have a 1.3kohm resistor to ground on the output so i don't think an additional resistor is necessary. Plus I already have the PCBs and the pins match. I am interested in buffers for another project though. Ill let you know.
  2. What Are You Building Today

    So I thought I would try out reflow oven soldering with a toaster oven. The AMB regulators for the Dynalo Mini are $40 whereas the toaster oven was practically free. I figured trying to solder with the toaster would be worth a try. It would also help with all the other SMD projects I have. I don't have a controller for now so I did it manually. As a test I bought an SMT adjustable power supply kit from Nightfire electronics. I had a little too much solder for the LM317 and one resistor didn't self-center but I'm pretty satisfied with the result. I'm thinking about using this for the R2R attenuator board. Anyone know what the procedure is for doing reflow on 2 sided boards?
  3. Balanced to unbalanced board

    When matching transistors do you only need to match complimentary pairs? Or do all the transistors on one channel need to be the same?
  4. The Multi Amp aka Dynalo Mk2

    Damn, i wish I knew chinese. I see you made the TKD version @astro, would you mind posting the front panel layout?
  5. The Multi Amp aka Dynalo Mk2

    There's a fuse near the switch. Nice work @astro! Where did you do your casing? Are those temperatures inside the enclosure? Are there holes underneath?
  6. KG Balanced Dynahi build discussion thread

    They should be able too. All these transistor testers are based on some open source project https://hackaday.com/2015/04/24/review-transistor-tester/
  7. Balanced to unbalanced board

    I drew a schematic of the diamond buffer in case anyone needs it KG-Diamond-Buffer.pdf
  8. Balanced to unbalanced board

    Verical has 2sc3324-GR but not 2sc3324-BL. KG mentioned that the highest hfe should be used which is the BL version.
  9. Balanced to unbalanced board

    Digikey says that 2SC3324/2SA1312 is NRND and is recommending 2SC2713/2SA1163 as a substitute. Any reason why I wouldn't be able to use the 2SC2713/2SA1163 transistors for the unbalanced/balanced board and diamond buffer? Comparing the datasheets for 2SC3324 and 2SC2713 it seems like the 2SC3324 has a lower noise figure, but otherwise have identical specs. 0.2dB and 1dB max vs 1dB vs 10dB max respectively. Seems like I should go for the original pair while I still can. Too bad it's backordered on Mouser until March.
  10. The Multi Amp aka Dynalo Mk2

    I got lucky and was able to make a small order. Minimum order is 1000 pieces. If there was a group buy with a minimum of 20 each we might be able to reach that. A lot of people bought multiple pots so maybe someone is kind enough to sell one to you. otherwise it’s probably better to do the version with the TKD pot, which you can order direct. Or air wire an ALPS pot like someone else here did.
  11. Balanced to unbalanced board

    Another edit to your BOM. The transistors should be the BL type, not the GR. So the 2SC3324 transistor should have mouser part 757-2SC3324BLTE85LF
  12. The Multi Amp aka Dynalo Mk2

    I’m not running anything yet, just trying to understand a bit more before building. I have all the parts for the Dynalo mini but no chassis or heatsinks for the output transistors yet. I just know that in general people have been getting higher temps from the mini but it seems strange if the bias current isn’t higher then what people are running for the full size version. I plan to do +/-20v like others have done, but might do 18v if it runs cooler.
  13. The Multi Amp aka Dynalo Mk2

    So what’s the story of the higher heat on the SS Dynalo Mini over the SS SMT Dynalo? Is it because the transistors are in a smaller area and there’s less copper to dissipate heat? Or the circuit/layout isn’t the issue and the smaller enclosure just has less space for cooling?
  14. Part Sourcing Assistance/Advice Thread

    There’s no real store that has the PCBs. You either need to make them yourself from gerber files or wait for a group buy. You can probably check the ‘for sale’ forum here.
  15. Part Sourcing Assistance/Advice Thread

    Thank you Justin!