Forward Voltage Drop of stock Si diodes in Soul Food?

Discussion in 'Effects, Pedals, Strings & Things' started by Jeff West, May 26, 2015.

  1. Jeff West

    Jeff West Member

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    Sorry if this has been covered before, but what are you guys measuring for the fwd voltage drop in the stock diodes in E-H Soul Food? I measured about .280 in circuit, but I'm not sure if my meter is well calibrated. Most but not all of the vintage British and U.S. Ge diodes I have on hand test a bit lower than this with the same meter, ~.250. Thanks for any input-
     
  2. analogmike

    analogmike Gold Supporting Member

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    Yes they measure about the same as a germanium diode, though they are not normal germanium or silicon diodes (schottkey?)
     
  3. Jeff West

    Jeff West Member

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    Thanks, Mike. Do you recall which type of Ge diodes you tried that didn't really sound different from stock? Just messing around with some substitutes I found that UK made OA47 and CV7127 seemed to work especially well, among others.
     
  4. Rydell

    Rydell Member

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    I've had some luck with a pair of 1N270's in my Silver Pony. Definitely prefer them over the "stock" D9E's. They might be worth a shot in the Soul Food.
     
  5. amz-fx

    amz-fx Supporting Member

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    Yes, I think they are schottky diodes - the 0.28 Vf is exactly the same as I measured in the 1N5819 diodes that I have on hand.

    regards, Jack
     
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  6. cj_wattage

    cj_wattage Vendor

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    0.3V is about right for most Schottky diodes. But forward voltage drop is a function of current, so as current increases, so does Vf. Most effects pedals have fairly low current draw, especially in the audio path (where clipping diodes are situated).
     

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