Covert Overdrive JFET question

[Guybrush]

Hi all

I'm struggling to find the through hole MPF4393s JFETs (or the SMD equivalent) needed for the Covert Overdrive.

I've previously built this circuit using a different board which listed J201s instead of the MPFs. I have fortunately got a few J201s in my parts box so I would just like to know if I can use these inplace of the MPF4393s using the Covert Overdrive board.

All guidance gratefully received.

Thanks

 

[Flying]

I hope you don't mind if I tack a question on to yours.

I have previously bought some SMD MMBF4393 which now appear to be a discontinued line, replaced by MMBF4393LT1G, I have no idea what the ‘LT1G’ suffix means, but hoping these are basically the new version of the MMBF4393 and the difference being that they are Pb−Free, RoHS Compliant etc.

Can any one shed any light on the new version and if it’s a direct replacement of the original.

 

[jjjimi84]

Hi all

I'm struggling to find the through hole MPF4393s JFETs (or the SMD equivalent) needed for the Covert Overdrive.

I've previously built this circuit using a different board which listed J201s instead of the MPFs. I have fortunately got a few J201s in my parts box so I would just like to know if I can use these inplace of the MPF4393s using the Covert Overdrive board.

All guidance gratefully received.

Thanks

The pinout is the same, although you may need to adjust bias to get them within range.

I hope you don't mind if I tack a question on to yours.

I have previously bought some SMD MMBF4393 which now appear to be a discontinued line, replaced by MMBF4393LT1G, I have no idea what the ‘LT1G’ suffix means, but hoping these are basically the new version of the MMBF4393 and the difference being that they are Pb−Free, RoHS Compliant etc.

Can any one shed any light on the new version and if it’s a direct replacement of the original.

Should be fine

 

[music6000]

Hi all

I'm struggling to find the through hole MPF4393s JFETs (or the SMD equivalent) needed for the Covert Overdrive.

I've previously built this circuit using a different board which listed J201s instead of the MPFs. I have fortunately got a few J201s in my parts box so I would just like to know if I can use these inplace of the MPF4393s using the Covert Overdrive board.

All guidance gratefully received.

Thanks

Look for PN4393, Same Transistor!
I used these in my PedalPCB Sabbath build :

 

[Chuck D. Bones]

Covert uses Mu-Amp configuration and as such is very forgiving of which JFET you use. If Vp is around 2V, you're good to go. Socketing JFETs is probably a good idea if you haven't tested them.

 

[okstateblues]

https://www.mouser.com/ProductDetail/Central-Semiconductor/PN4393-PBFREE?qs=OlC7AqGiEDnlEKOM7U%2FSaw%3D%3D

Here are the ones I used on a tweedman build that called for those. Hope it helps.

 

[Chuck D. Bones]

Good to know that xx4393 JFETs are still in production. Not a bad price, especially when purchased in bulk.