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CrystalFET Phono Stage

Posted 3rd March 2016 at 05:55 AM by rjm
Updated 21st April 2017 at 01:46 AM by rjm
Development thread here. Web page here.

CrystalFET is a J113 jfet-based two-stage phono preamp, with passive equalization and on-board MOSFET-based shunt voltage regulator.

Jfets Q1 and Q3 should be matched between channels, and for best results the value of drain resistors R2 and R9 should be selected based on the jfet pinch off voltage of Q1 and Q3 respectively.

rev. 1.4e (final version) removes some unneeded resistors and tidies up the board layout a little. The resistors have been renumbered.
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Attached Files
File Type: zip pcb-crystal-14e-bom.zip (246.7 KB, 52 views)
File Type: asc Crystal 14.asc (11.2 KB, 150 views)
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Total Comments 6

Comments

  1. Old Comment
    I am up for a giving the new stage a try. Let me know.
    Walt
    permalink
    Posted 4th March 2016 at 12:37 AM by waltroman waltroman is offline
  2. Old Comment
    rjm's Avatar
    Thanks! I will order some boards soon whatever happens, just ... because I'll be ordering other stuff anyways. I'll be in touch.
    permalink
    Posted 4th March 2016 at 06:12 AM by rjm rjm is offline
  3. Old Comment
    Count me in also....
    permalink
    Posted 24th March 2016 at 05:28 PM by richandy richandy is offline
  4. Old Comment
    rjm's Avatar
    Boards arrive today. More soon.
    permalink
    Posted 25th March 2016 at 06:03 AM by rjm rjm is offline
  5. Old Comment
    How / where can I order the kit?
    permalink
    Posted 4th April 2016 at 05:08 PM by richandy richandy is offline
  6. Old Comment
    rjm's Avatar
    PM sent!
    permalink
    Posted 4th April 2016 at 11:35 PM by rjm rjm is offline
 

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