Uncle Peter wrote:

I always wondered why Motorola (of all peopled) used PNP RF
transistors in the final and two driver stages in their Micor base
station and mobile radios.


Were those perhaps germanium transistors? The first Ge transistors were
PNP, and the first (Ge) audio power transistors I recall seeing in wide
use, in auto radios, were PNP. I'm not sure why PNP was favored in the
early days, whether due to some basic physics reason or some more
practical processing or production considerations.

Roy Lewallen, W7EL