> This results in a transistor with low beta - but I'm not sure if it 
> is
less than 1.

In my case it's a "forced Beta" of less than one.

Forced Beta is where you purposefully drive the base harder than it 
may need to ensure the transistor is turned on as hard as it can be. 
eg for many power transistors you see Vcesat (CE voltage when fully 
on) specified for a base current of 10% of the collector current. ie a 
forced beta of 10. It MAY be that the transistor would turn on just as 
hard if Ic/Ib was 20 or 30 or 50:1 but the 10:1 spec usually ensures 
it is well and truly hard fully on.

In my case the collector current is about 0.5 mA and the base current 
is about 1 mA so forced Beta = 0.5/1 = 0.5 :-)

Most unusual.

> I have used this arrangement [[reverse C & E]] in the past to reduce 
> the sensitivity of
a "SCR" type circuit made up of an NPN and a PNP transistor. ...

> Makes people scratch their heads when they check the circuit 
> however.

Indeed :-)

But you need to watch Vce (or Vec in this case :-) ?) breakdown when 
C&E are reversed. Many traansistors break down into a really nicely 
noisy and not very sharp zener around 8-12 volts when reverse biase 
with base open. People use this configuration as a noise generator. .



        RM

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