Biasing a low voltage Mu Amp [?]

[petemoore]

With the success of 1.5v-3v operation of a couple of gain stages, thanks to Jack Ormans new AMZ article, I'm curious to find out about trying this with a Mu Amp, reasons why I shouldn't be, or just to try it.
 Anyone with suggestions as to biasing a Mu Amp to a Low Voltage supply are welcomed !!1

[Tim Escobedo]

The way I do them, they work at low voltage.

[amz-fx]

I'm curious to find out about trying this with a Mu Amp, reasons why I shouldn't be, or just to try it.

Just crank back on the voltage to the  mini-booster...  it will work down to quite low voltages and is self biasing to some degree.  The only change is that the source resistor should be decreased to about 100 - 150 ohms.

regards, Jack

[R.G.]

The mu-amp - or its more useful version, the SRPP - works to low voltages *if* you build it with a low Vp JFET. The J201 qualifies, so most of the J201 versions work. But don't expect a MPF102 version to work from 1.5V.

[puretube]

here`s the hivolt version (the original, the first one)...
http://l2.espacenet.com/espacenet/bnsviewer?CY=de&LG=de&DB=EPD&PN=US2310342&ID=US+++2310342A1+I+

from 65 years ago  

[Alpha579]

The mu-amp - or its more useful version, the SRPP - works to low voltages *if* you build it with a low Vp JFET. The J201 qualifies, so most of the J201 versions work. But don't expect a MPF102 version to work from 1.5V.

sorry RG, but whats the SRPP?

[puretube]

sorry- I haven`t been asked explicitly - , but nevertheless:
http://www.tubecad.com/may2000/
http://www.tubecad.com/june2000/