"Fleetie" wrote in message

"Arny Krueger" wrote
"The biggest problem with the amps is poor current haring between
the output triodes. All 4 need to be matched closely to prevent
failures. Initial matching on the bench ensures initial
reliability." A hearty DOOOH! to that!

**** me. It must be a **** design then.

Do you design a transistor circuit making assuptions about h_FE?

Yeah, I presume that h_FE will be all over the map. While Trevor is right
about a given device sample having stable characteristics, that's only true
if the device is operating under tightly-controlled circumstances that are
unrealistic in the real world.

IOW h_FE varies with temperature, current, applied voltage...

And it varies from device to device.