Jinx wrote:
>Attachment Converted: C:\WIN31APP\EUDORA\ATTACH\dsofront.gif

Rich Ottosen  wrote:
>
>            about          +V
>        +-- 5pf--+         |
>        |        |         |
>        |        |      |--
>  >--+--+--100K--+--+-->|     JFET (2N5486)
>     |           |  |   |--
>     |   diodes  ^  V      |
>    1Meg         |  |      |
>     |           |  |      +----->> to preamp
>     |           V  V      |         (0 volts out for 0 volts in)
>     V                     |
>                        |--
>                    +-->|     JFET (2N5486)
>                    |   |--
>                    |      |
>                    |      |
>                    +------+
>                           |
>                           |
>                           -V
>


I think a good modification for the ckt shown by Sir Jinx-GFW
in his attachment might be to change R20 from 470 ohms to say
100K, and put a 20 pF cap across it, similar to what Rich shows
above. The 100K should pass along DC/low-fequencies well, and
the cap will pass the high end. You also get OV clamping without
excessively loading down the input signal. I don't think I would
want to use the SJ-GFW ckt as originally shown.

- danM

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