BD140 I/o 9610 in Aleph type front end?

[kasey197]

I compared the BD140 vs the 9610 on a curve tracer and noted the dramatically higher transconductance on the BJT compared to the MOSFET. I don't have much experience with BJTs but they look like a nice upgrade to the 9610s on this front - before I go about making a complete *** of myself - can I just sub them into a aleph type diff pair front end ? Am I missing something obvious ?

 

[Zen Mod]

just try

be sure to have enough emiter degeneration - you really don't need all that OLG

 

[kasey197]

You mean just slot them in ?

 

[Zen Mod]

yup

say 22R for Re are good for start

though , I'll toss at least 100mA through LTP , these days , whatever is choice of biguns for it

decreasing Rd(Rc) accordingly

 

[kasey197]

Oooo 100ma thru an input LTP ? That at least 5 times more than has ever been done afaik but maybe you're onto something there zm ....

 

[Zen Mod]

I'm always onto something