Fender Blues Junior Question

[J Luth]

Can the Q1 JFET on a Fender Blues Junior be substituted with either a J112 or a J113? I’ll admit it, I don’t know much about them.
I can’t source a J11 locally. I can get it from Mouser but I really don’t want to order 1 - JFET. I am placing an order from Antique Electronic but all they is J112 or J113

Page 2 and 3 on the schematic.

[Jon Snell]

These obsolete JugFETs, (as is their original name by description), are basically the same so any will do the job of switching.

[Jon Snell]

J111, 112 & 113 are similar but the knee point varies.
Why not purchase original parts from Mouser; https://www.mouser.co.uk/c/?q=J111
They are obsolete but it looks like they have a few thousand left in stock.

[loudthud]

If you don't know much about them, how do you know it's bad ?

Many people assume JFETs are bad when they see the Rds(on) in an Ohm check. It is normal to see this resistance when checking with a DVM.

J111 Rds(on) = 30 Ohms max
J112 Rds(on) = 50 Ohms max
J113 Rds(on) = 100 Ohms max

You really need the J111.

See my comments in this thread: https://music-electronics-forum.com/...tremolo-issues

Also see what I posted in this thread: https://music-electronics-forum.com/...el-ss-amp-hiss

[J Luth]

If you don't know much about them, how do you know it's bad ?

Many people assume JFETs are bad when they see the Rds(on) in an Ohm check. It is normal to see this resistance when checking with a DVM.

J111 Rds(on) = 30 Ohms max
J112 Rds(on) = 50 Ohms max
J113 Rds(on) = 100 Ohms max

You really need the J111.

See my comments in this thread: https://music-electronics-forum.com/...tremolo-issues

Also see what I posted in this thread: https://music-electronics-forum.com/...el-ss-amp-hiss

It has a broken pin.

I'll get it from Mouser if he is willing to pay the shipping. I don't need anything else from Mouser right now. If I did I would add it to an order.

[nevetslab]

Ah, rats! Yet another common part gone obsolete and requiring buying up inventory so I have spares. At least this is something I can do while being laid up with my broken leg. I too don’t have additional parts I need to lessen the pain of shipping cost. Thanks for the update!

[Jon Snell]

The J111 is still being manufactured as an MMBFJ111
SMD type but simple to fit on the exixting lands for the still well stocked but obsolete J111.
They are made by OnSemi and Fairchild. As was the J111.

[J Luth]

Thanks for the help. This has taken a turn for the worse. I be starting a different thread about the amp.