1N4739 - Any substitutes that will work in an ADHD build?

[e_man_89]

Missed the designation on the parts list and didn't order any. Just trying to avoid more waiting...

Are there any diodes that would work in its place in this circuit?

Thanks for any info...

 

[wintercept]

What have you got for zener diodes? It’s there to protect the input of the JFET from voltage spikes (like static). It’s more commonly seen on MOSFETs as they’re more susceptible to static and what not. I’ve rarely seen it on JFETs.

The default there is a 9.1v zener, a 12v would work there just fine and provide adequate protection. It will also work without it and I don’t believe it’s that vulnerable for damage. But someone more knowledgeable might want to confirm that.

 

[e_man_89]

Thanks for the info wintercept, I do have a 12v in my stash so I might be good!

I would probably feel better about having something on the board rather than leaving it out.

I just wanted to find out if the 12v would be adequate. Thanks again.

 

[Chuck D. Bones]

Q5 is not nearly as susceptible to ESD as a MOSFET. Wintercept is right it's not absolutely necessary, but the added protections is a plus. Any zener between 4.7V and 15V will be fine.

 

[e_man_89]

Thanks Chuck D., I appreciate your input. Got some pots on order and the pcb is on the way.

I'm looking forward to this build.