idss of Toshiba J fets....

[chromenuts]

I think the comment has more to do with the fact that they are 6 idss matched 2sk170/j74 GR, which is at the top of the GR range. GR overlaps with the BL idss range around 6. Most info I remember reading stated GR fets have an idss measurement that is too low to be used in the FW designs effectively. I was lucky enough to get some matched GR with a usable idss a while ago at a sane price.

Thanks for the information about the turbo F5 boards Dennis and 6L6.

P.S. I’ve only ever mounted dodofets close to the board on one project (it was my first)...a phono amp. I ended up having a problem with some 2sk170GR and had to de-solder and replace them (most likely due to overheating) ...what a PITA! Ever since I’ve been mounting them at full leg length in my projects.

 

[grimberg]

Has anyone tried socketing in the jfets so they can be easily removed for reuse?

Like this? That amplifier has been used daily for over a year without any issues.

 

[Dennis Hui]

Yes, I was thinking of something like that. Thanks.

 

[chromenuts]

Do you have a part number/source for the socket? I was trying to do something similar in the ACAs I built when I decided to try some Semisouth in them. I ended up hacking something out of a Radio Shack 18 pin IC socket.

 

[chede]

I have socketed the 2SJ74 / 2Sk170 in my M2 as well, no issues so far.

To cut off the number I need when socketing something I use something like this:

MPE 006-1-050: Precision socket strip 2.54 mm, 50-pin at reichelt elektronik

For the J-FETs, it's more like this:

MPE 006-1-003: Prazision-Sockelstreifen RM 2,54 3-pol. bei reichelt elektronik


😉
Best regards,
Claas

 

[grimberg]

This is the one I use. It comes in a 20 position strip which is notched and easy to cut with a utility blade.

310-87-120-41-001101 Preci-dip | Mouser

 

[astromo]

Regarding a socket, what thoughts do forum goers have to this sort of deal?
6 Pin Socket
I'm thinking this could do well for an Aleph J, where the JFETs bump heads to keep each other warm.

 

[Stanislav]

Has anyone tried socketing in the jfets so they can be easily removed for reuse?
If that's a bad idea, maybe leaving the leads long when you solder them?


Dennis

Yes, my Pearl I phono pre, using 2SK369 instead is entirely socketed.
Been playing glorious vinyl for quite some time.

Remember Revox R2Rs had all their semis on sockets (not to mention the plug-in cards).