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Old 5th Sep 2010, 12:22 pm   #4
Mr Moose
Heptode
 
Join Date: Jul 2008
Location: Gloucestershire, UK.
Posts: 971
Default Re: Transistor Choice in radio project

Hello,
Towers gives the minimum Hfe (Common emitter current gain) for each type as follows:-

OC71 30 (minimum) @ 5mA bias

OC81 50 (minimum) @ 100mA bias

OC81D 20 (minimum) @ 5mA bias

I think there can be quite a variation in gain with different transistors of the same type.

Yours, Richard

Last edited by Mr Moose; 5th Sep 2010 at 12:32 pm.
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