Fender Pawnshop Excelsior tremolo question

[kagliostro]

Looking for the Marshall 1959T tremolo schematic, casually I've find the Fender Pawnshop schem



Whole schematic
http://www.diyitalia.eu/forum/download/file.php?id=10940

in this tread PRR explained the function of the 2g374 on the 1959T circuit

http://el34world.com/Forum/index.php?topic=7261.msg64156#msg64156



but as I have poor knowledge of SS I'm not able to understand the tremolo circuit on the Pawnshop Excelsior on which there is an IRF820

Someone can explain how the Fender Pawnshop tremolo uses the mosfet ?

Is it there only as a Source Follower and if it is, why they used a SF in a tremolo that usually hasn't one ?

Thanks

K

[VMS]

There is a cathode follower in older fender tremolos (tweed and blonde era), for example in vibro champ or tremolux:

http://ampwares.com/schematics/tremolux_6g9b.pdf

I'm not good at explaining the reason for this but maybe someone will chime in.

[kagliostro]

Thanks VMS

Franco