On Thu, 19 May 2011 09:02:42 -0500, "Dave" wrote:
"Dave" wrote in message
news
Am trying to bias the JFET in the attached schematic to feed signal to the
following BJTs while keeping Vgs very near Pinch-Off. Works fine as long
as the batteries are fresh, but as they begin to wane Vgs surpasses
Pinch-Off (which is 4.0 volts for the JFET I am using, while I try to hold
it at 3.95 VDC.) It has been suggested that I use a BJT (configured for
Common Emitter) to do this, but I am in the dark as to how this might be
accomplished. ANY help would be greatly appreciated...
Thanks,
Dave
Forgot to mention or specify: Id is limited to 3 mA for the NTE451. Thus
the note about Vs being 9.6 VDC in the schematic.
Dave
Let's back up a bit and ask a few questions...
Is the object to firmly set NTE451 Id bias at 3mA?
What is the useful range of battery (17V) voltage?
...Jim Thompson
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