On Sun, Aug 23, 2015 at 7:24 PM, Dominique Dumont domi.dumont@free.fr wrote:
On Sunday 23 August 2015 20:14:18 Dominique Dumont wrote:
When the input is 0, the transistor emitter is driven to ~ 0.3V which should switch off the transistor.
Even better, the emitter can be driven to 0 V bby putting the 100k resistor before the 10k. (attached png)
Hope this helps
yeay :)
ok so i looked up the datasheet for the 2N3904: http://www.mouser.com/ds/2/149/2N3904-82270.pdf
collector-to-emitter is ~0.3 volts, base-to-emitter is 0.65 maybe as high as 0.95 volts.
i'm horribly confused, now. i thought i knew how transistors worked!
this circuit (in the section "serial") looks much more obvious, to me. and the Rds(ON) for low current is reported to be around 0.09v. http://people.physics.anu.edu.au/~dxt103/472/wspr_tx/
l.