[sdiy] 9V battery vs. 9V psu power

[Scott Gravenhorst]

"JH." <jhaible at debitel.net> wrote:
>Your transistor's be reverse breakdown voltage ("zener" voltage)
>may be just low enough to work with 9V, but not with something like
>8.8V anymore ...
>Rememeber, the data sheet specifies a minimum voltage here, it may be
>considerably higher.

Aha, so if that is the case, couldn't one connect the diode bias
resistor to -9v instead of ground and increase also it's size?  It's
AC coupled to the opamp input, so this shouldn't cause a problem.

>
>JH.
>
>
>----- Original Message ----- 
>From: "Karl Ekdahl" <elektrodwarf at yahoo.se>
>To: <synth-diy at dropmix.xs4all.nl>
>Sent: Sunday, January 15, 2006 7:27 PM
>Subject: [sdiy] 9V battery vs. 9V psu power
>
>
>> I have a noise source that refuses to work from a dual
>> 9V battery split supply, but that works perfectly with
>> a +-9V psu. I can't for my life figure out what to do
>> to make it work, the only difference i can see is that
>> the batteries will drop in voltage a little after
>> usage. I used this shemo by René Schmitz:
>> (http://www.uni-bonn.de/~uzs159/noise.png)
>>
>> thanks
>>
>> Karl
>>
>

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