Noise problem

  • gihaume wrote:You need to put a 2SC828 with a hFE of at least 300.
    Anyone who can tell me how to know that (hFE=300) when you're buying?
    I tried a bag of 20 2SC828 from ebay, but the highest score I got was 281... :?
  • maglar wrote:
    gihaume wrote:You need to put a 2SC828 with a hFE of at least 300.
    Anyone who can tell me how to know that (hFE=300) when you're buying?
    I tried a bag of 20 2SC828 from ebay, but the highest score I got was 281... :?
    In case someone's interested: I got me 50 2SC828 from eBay and the second one I measured had hFE value of 325. Put that in but still had to replace the 100k trimmer for 200k to come down to 130mV. Thanks all you guys that posted on this forum. My build is complete and calibrated. Sounds really great! :D
  • You have components that are off the noise section specification, probably beyond own tolerance also. And that's it. Solution, change of system resistance or replacement of opamp. I never had any problems with it, and I made Yocto 2 near ten pieces . I always check the individual components whether they are within the manufacturer's own and sub-manufacturer tolerance. Especially in arrangements such as Noise, etc. I got not so long ago, several hundred resistors 0.1% Dale, which actually had median up to 5.2% !!!! From Mouser.
  • You may also want to check the service manual to apply the changes which weren't put in Yocto1... not sure about the v2.