Hoffman Amplifiers Tube Amplifier Forum
Amp Stuff => Tube Amp Building - Tweaks - Repairs => Topic started by: kagliostro on January 13, 2024, 09:20:22 am
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I was reading a thread (at Ampgarage) about the Sano 300 Amp
a schematic was found and I managed a bit to have it more readable
a guy noticed that the jfet 2N5461 on the schematic has something of odd
and infact the simbol used is the simbol of an SCR Diode instead of the simbol of a jfet
(https://i.imgur.com/vEBFxBk.jpg)
As I understand near nothing about Solid State I don't understand what those two Jfet are doing on the circuit and it will be nice to have info about
the more, I've put 3 letters A - B - C on the connection of what seems an SCR, if someone can indicate the corrispondance of A - B - C with the Source - Drain - Gate of the jfet I would like to try to correct the schematic putting there the correct simbol for the jfet
(https://i.imgur.com/vNpu4gN.jpg)
Thanks
Franco
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The attached pic shows the correct way to connect that jfet. The tremolo signal is applied to the gate and simply varies the resistance between the drain and source, thus changing the gain of V1a and/or V1b.
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As I understand near nothing about Solid State I don't understand what those two Jfet are doing on the circuit and it will be nice to have info about
The Jfets allow for one tremolo signal to be connected to both channels while keeping the cathodes isolated from one another; a reverse mixer if you will. You could accomplish the same thing with SCRs which may have been the original intent.
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You could accomplish the same thing with SCRs which may have been the original intent.
I don't see how that's possible in this circuit since there is no current flow through the jfet.
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As I understand near nothing about Solid State I don't understand what those two Jfet are doing on the circuit and it will be nice to have info about
You could accomplish the same thing with SCRs which may have been the original intent.
Maybe they thought as I did :w2: :smiley:
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Ciao Steve
Many thanks
Many thanks also to you astronomicum
Franco
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2N5461IS a JFET.
Just because some guy in Irvington NJ (I've been there) drew it wrong is no reason to go off in the weeds.
https://www.jameco.com/Jameco/Products/ProdDS/253905.pdf
https://alltransistors.com/adv/pdfdatasheet_motorola/2n5460_2n5461_2n5462.pdf
http://www.larryjohnmcnally.com/sano_amps.html