B1 jfet help .

[early]

Hello all ,

I'm new around here and I'm in the process of ordering up bits to make up the B1 .

Now please forgive me if this is a stupid question but I'm new to playing with these new solid state thingies ( I've much more experience with valve circuits ) and am not that clued up on them .

Here in the UK I'm struggling to find 2SK370 fets in the usual places
RS , Farnell ect .

However Farnell have 2SK3702 is this the same / alternative ? .
Also I can get J310 is that a drop in replacement for 2SK370 or will the circuit need adapting .

Thanks in advance , e .

 

[korben69]

2SJ108 = 2SJ74
2SK370 = 2SK170

BL grade prefered

Have a look there, Spencer provides matched pair and quads :
http://www.diyaudio.com/forums/showthread.php?s=&postid=1902356#post1902356

Cheers !

 

[early]

Thanks Korben ,

I'm still confused , is a 2SK3702 a different grade of 2SK370 ? .

Anyway being the impatient type I've ordered both J310 and 2SK3702
It's not going to break the bank to try them .

Thanks for the link , but 100 of 'em is way too many for me .


Cheers , e .

 

[h_a]

Sorry for the (too) late reply!

2SK370 is a JFet made by Toshiba in a small package.
2SK3702 is a MosFet made by Sanyo and comes in a large package.
J310 is a JFet.

The 2SK3702 is not a replacment for the 2SK370; the J301 is a least a jfet, but unfortunately with a smaller voltage rating and smaller transconductance. I don't know the details of the B1, it might work (maybe modifications needed).

Sorry for the news, but I would recommend getting the original part, even if you have to order it from Dalbani or some other specialist for small signal parts.

Have fun, Hannes

 

[korben69]

2SJ74 and 2SK170 are available in 3 different grades V, GR and BL.
Both are Toshiba JFet.
BL grade is prefered for B1.
Spencer delivers matched sets, there's no need to order 100 units...
Send him a mail for your request, he's very reliable

 

[early]

Thanks for the replies .

I have now built ( well breadboarded ) the B1 , and the J310 works a treat ! .

Just need to sort out some case work now .