source for Toshiba 2SA1316BL transistors

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band_master

Well-known member
Joined
Mar 14, 2011
Messages
68
hey gang,
I have a blown channel on my Sytek mpx-4aii and I think these transistors need to be replaced. Does anyone know of a source? I ordered some from this supplier but they turned out to be the GR version instead of BL.

http://www.futurlec.com/Transistors/2SA1316.shtml

There is a guy on eBay selling them but for $4 each. Just wondering if anyone knows of a cheaper B2C source.

thanks,
BD
 
The difference between the GR and BL suffixes is the hfe of the transistor: GR = 200-400, BL= 350-700

Note that there is a bit of overlap there, so a GR that tests high *could* be used in place of a BL that tests low.  Of course Sytek may have selected theirs for a particular hfe, but it won't hurt anything to try the ones you have.
 
my meter doesn't measure Hfe so i walked down to the shack and picked up one that does. was getting readings of 615 hfe flashing on the GRs I have before the meter would read 0f(?). not sure what that is about but thought I would just pop them in the circuit and see what happens. well, this channel is alive and well now. sounds pretty much the same as channel 2 so...should i be worried about having GR transistors in channel 1 instead of BL? sytek likes to make a big deal about how their transistors are "hand-picked" for blah blah blah. thanks for the advice!

BD
 
If all of the ones you used measured the same or close, I wouldn't worry.  They may have selected for a specific value, lowest noise, or other specs, but if it sounds good it is good!  Just to be safe, measure voltages at all the legs compared to the other channel to make sure there is not still a problem with the circuit which will cause the new transistors to fail.
 
In principle the higher beta parts will have less base current for same collector current so be lower noise. I wouldn't expect the difference between GR and BL to be very apparent in use.  Of course replace them in pairs.

JR

PS: If matching beta it should be done close to the current they will be biased at in use.
 
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