1. Time for some upgrades in server hardware and software to enhance security and take AK to the next level. Please contribute what you can to sales@audiokarma.org at PayPal.com - Thanks from the AK Team
    Dismiss Notice

KR-8050 Resistors

Discussion in 'Kenwood-Trio/Kensonic-Accuphase' started by rbspop, Nov 5, 2018.

  1. rbspop

    rbspop rbs55pop Subscriber

    Messages:
    163
    Location:
    Reno, NV
    I shall take a chance and presume that Kenwood installed the resistors on the Preamp board in a vertical orientation to save space and/or shorten the signal path. At-any-rate: I have two questions. What is the coating they used on the exposed part of the legs? And what are the good/best resistors to use as replacements? BTW: I just placed the resistor in C25 to get a pic.

    Resistor.JPG
     

     

    Please register to disable this ad.

  2. mbz

    mbz Super Member

    Messages:
    2,174
    Location:
    Melbourne, Victoria
    Pic of a low noise resistor. The leeds act as antenna picking up stray fields.
    To combat this, the resistor is mounted on one side/butt so no exposed leed.
    The other leed is coated with "dunno" to shield the fields. You could use some
    stripped wire insulation.

    Plenty of choices, metal film preferred. Look for lower thermal drift. I'm
    currently using Yageo MFR, 1% +/-50ppM/C. Vishay make some good resistors also.
     
    dlucy likes this.
  3. rbspop

    rbspop rbs55pop Subscriber

    Messages:
    163
    Location:
    Reno, NV
    Interesting ... Those are the resistors I just ordered. There are several bare wire jumpers on the board; however, I think that I will just use the "stripped wire insulation" method. Thanks
     
  4. Watthour

    Watthour Electron Rancher - JS3600

    My guess is that it is done to conserve space. Other circuits might do that to provide additional cooling.

    Principled engineering doctrine would indicate that 4" of copper foil on the board being terminated by a connection at a right angle constitutes a dipole antenna. If noise rejection was the goal, they selected a rather poor method of accomplishing that. And MBZ is correct - A metal foil or carbon would be more suitable than a wirewound, since a wirewound (even non-inductive) would tend to act as a loading coil for that miniature dipole antenna.
     
    dlucy likes this.
  5. rjsalvi

    rjsalvi Well-Known Member

    Messages:
    559
    Location:
    San Diego, CA
    It's usually done as a result of lack of board real estate and the coating is called conformal coating...the same stuff coating the resistor itself.
     
    dlucy likes this.

Share This Page