[Amps] Regulated AB Bias schematic

[G3rzp@aol.com]

There was quite a good one in the old RCA app notes. The problem is that  you 
need a zero impedance supply pushing a constant base current into the  
devices, possibly even reducing slightly, as the temperature goes up  and the Vbe 
goes down, while the Hfe goes up. The best practical  approach is a constant 
voltage supply that decreases as temperature goes up and  so tracks the drop in 
Vbe.
 
73
 
Peter G3RZP