buffer with jfet pinout: do D and S not matter?

[paulbarrette]

Looking at a buffer schematic, the G is in yellow below. But I am assuming that the drain and source are interchangeable since they are not labeled.
While I am at it, can a electrolytic be used in C2 (neg towards out)?

thanks
Pb

 

[giovanni]

Yes, drain and source are interchangeable in JFETs and MOSFETs.

 

[paulbarrette]

Yes, drain and source are interchangeable in JFETs and MOSFETs.

Thanks
Pb

 

[darwin999]

@paulbarrette -
The convention for the JFET symbol has the gate connection (the one w/ the arrow) immediately opposite from the source.
So in your diagram, the source is thus implicitly labelled.
I just wanted to note that for the following reason: while all the common FETs we encounter in stompboxes are symmetrical, there do exist FETs that are asymmetric.

 

[paulbarrette]

@paulbarrette -
The convention for the JFET symbol has the gate connection (the one w/ the arrow) immediately opposite from the source.
So in your diagram, the source is thus implicitly labelled.
I just wanted to note that for the following reason: while all the common FETs we encounter in stompboxes are symmetrical, there do exist FETs that are asymmetric.

Ok. That makes sense with the arrow off to the side. Some schematics put the arrow in the middle. Hopefully when it matters there will be labeled pins

Thanks
Pb

 

[darwin999]

Some schematics put the arrow in the middle. Hopefully when it matters there will be labeled pins

Absolutely yes!

 

[Feral Feline]

...While I am at it, can a electrolytic be used in C2 (neg towards out)?
...

Yes, an electrolytic could be used, + towards the transistor, negative to out.

At the risk of starting the debate of electrolytics vs tantalum all over again, I'd put a 10µF tantalum in C2, + towards the transistor.

 

[paulbarrette]

Yes, an electrolytic could be used, + towards the transistor, negative to out.

At the risk of starting the debate of electrolytics vs tantalum all over again, I'd put a 10µF tantalum in C2, + towards the transistor.

Interesting. I note that pedalpcb design asks for a 10u mlcc which i had to google. That looks like ceramic. You prefer a tantalum over ceramic as well?

Thanks
Pb

 

[Feral Feline]

Interesting. I note that pedalpcb design asks for a 10u mlcc which i had to google. That looks like ceramic. You prefer a tantalum over ceramic as well?

Thanks
Pb

I just don't have any MLCC that big on hand. For sure I'd use MLCC, too. Whatever is going to make the circuit its best.

I've read that the Tantalum will last much longer and are more reliable than an Electrolytic.

There is open debate as to whether Tantalum sounds better than Electrolytic. Some people can't stand Tants.

 

[paulbarrette]

I just don't have any MLCC that big on hand. For sure I'd use MLCC, too. Whatever is going to make the circuit its best.

I've read that the Tantalum will last much longer and are more reliable than an Electrolytic.

There is open debate as to whether Tantalum sounds better than Electrolytic. Some people can't stand Tants.

I don’t mind electrolytic but i haven’t heard tants or mlcc. My usual part shop doesn’t sell them Nextgenguitars. I will have to try them sometime

Pb