BF244A's from small bear...sub for BF245A??

[vacuumdust]

HI...NOTHING BAD TO SAY ABOUT SMALL BEAR  but I've received BF244A's twice now from small bear when I actually ordered 245's.  Can the 244's be subbed for 245's (maestro FSH-1 build).  My guess is that small bear is out of 245's so they gave me a substitute??  Thanks for any help.

[petemoore]

  Well the main difference that'd matter would be polarity of the diode [PNP or NPN], and that you want the right way [for a Neg OR Pos gnd] circuit, and make sure the pinout matches.
  Otherwise it's a gain call, and maybe either stock # has gain Hfe's/leakage numbers which fall where they fall...it's more about the 'individual actual' readings than stock part #'s.
  Short answer is if they're the right type of transistor, say PNP, yes the numbers probably matter not at all about actual leakage and gain.
  Guessing they're "right", I always double check diode polarity before applying power...by sticking them in the DMM's Hfe meter finds the pinout.   

[vacuumdust]

Well, the pinouts don't match but I suppose I could twist the leads around.   The specs seem similiar with the exception of the Gate Source Voltage...the bf245a is 30 and and the bf244a is  negative 30.  Unfortunately I only ordered one transistor socket for the "noise" transistor in the circuit.  bummer   

[Gus]

First they are fets  The parts numbers are for pinout, case style and selection for the same Process #

Both are Process 50 fets IDSS 2ma to 6.5ma spread from looking at the PDFS Look at the other specs

Looks to be just a different pinout

Go to the fairchild site and look up the JFETS

[Gus]

vacuumdust

Did you understand my post?

[vacuumdust]

Yes, and thank you.  I'm finishing the build this afternoon.  I'll post later whether it works or not.  I have built this one (FSH-1) before...the first time I built it the result was flawless.  Worked perfectly...absolutely no noise issues.  I sold it on Ebay thinking I would just build another...HAHA...now I've had nothing but problems with ticking and whining and just plain failure.  In fact it's the only project i've ever given up on...threw the pcb away after stomping on it...got a new pcb from GGG and i'm about ready to finish it up.