... still not quite gone on holiday.
Wife several days gone.
Texts and calls from the Far North beckon.
Sleep but a distant memory ....
This better work first time ... :-)

...
> I'm working on a "HV" H-bridge for driving EL "stuff" from a micro,
> and while I fully expect to drive the bases with the typical 5-10mA
> in the base circuit, I expect the HV current to less than that most
> of the time.  Even driving a 12V relay with a transistor would
> involve very low betas (what; 20-50mA @ 12V from 5-10mA base 
> current?)

Yes. WhenVce > V_base-drive low Beta is valid as I mentioned.
In my case it's all low voltage. In fact both base and collector 
current are sourced from the same supply so not only Beta but also 
power ratios are 0.5:1. I could say what's happening (and somebody has 
been reading my mind)(and someone else utterly failed to) BUT this is 
producing such a diverse range of useful and interesting comment that 
I'll leave it a while longer - or until I come back if I ever get 
away. Today ... .
Looks at airline schedules. Decides MR2 will fly there about as fast 
and cheaper and more fun and more convenience.



        R zzzzzzzzzzzz M
        (Yes, I'll sleep a bit b4 I drive/fly)




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