Choosing a BNC

Discussion in 'General Electronics Chat' started by Dr.killjoy, Oct 8, 2014.

  1. Dr.killjoy

    Thread Starter Well-Known Member

    Apr 28, 2013
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    I am working on my analog 20mhz scope and fixing the blackout circuit ... But the Bnc connectors are dirty and I tried cleaning them but I think it's time for new ones ... My question is can I buy cheap ones off ebay or am I better off buying ones from mouser ??? Also should I find the capacitance of each connector or doesn't matter??
    Will gold plated Bnc make any difference or just for looks???



    Thanks
    Jay Sr
     
  2. crutschow

    Expert

    Mar 14, 2008
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    Cheap ones are probably okay but for the difference in cost, known brand ones may be built a little better and worth the extra.

    Any difference in capacitance between different BNC connectors should be too small to matter.

    Gold plated ones won't corrode as easily but likely make little difference in performance. I've seldom see then used, even on quality test equipment.
     
  3. Dr.killjoy

    Thread Starter Well-Known Member

    Apr 28, 2013
    1,190
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    OK I will stick with normal plated ones but does it matter if I get 50 ohm or 75 ohm ??? Won't the capacitance make a difference with compisation of the probes ???
     
  4. crutschow

    Expert

    Mar 14, 2008
    13,014
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    Yes it will make a small difference at high frequencies so select them the same as the scope input impedance, which is typically 50 ohms.
     
    spark8217 likes this.
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