Transistor as a Switch

Tons of 'em....
What is the load?
What is the input signal to the transistor?
How much voltage can you afford to drop across the transistor? (An FET may be better, there are plenty which will switch from logic levels)
What is your shoe size.
Del

first thank you for the response Del

well here is what I am trying to do. I am building a soft air turret controlled by an analog joystick. I am trying to come up with a way to fire the gun without actually pulling the trigger.

The load I would say is a motor that will take a voltage range of 8.4-9.6V with 1100-1400mA current ( even a max of 2400mA but I am not going to go that high there).

So my thinking was just connecting the power circuit just for the gun with a transistor in the middle. so Vdd would be the above range at a "collector" side and less than Vdd at the "base" which would be provided from my ARM processor. The "emitter" side would just feed back into the GND of the circuit for the gun as if the trigger contact was not there.

David

A picture is worth a thousand words.
A suitable transistor depends on your local supply really, look in the catalogues or online at any of the local suppliers.
Here is a link to 105 (scroll down) which are probably suitable (assuming you don't want surface mount parts).
Del

I may have more questions for my project later

thanks a bunch Del

never mind

Yes, plenty. See Newark or Digi-Key Electronics .

2N3055 springs to mind.....

Unfortunately my browsing time is very ltd so if you don't mind some pointers. TIP120 comes to mind. its Darlington which i believe would be necessary as the output port of the arm micro is ltd (dc current gain of the transistor(hFE) typically 1000 at Ic3A Vce 3V). As to the dc motor it drives pls remember a back emf diode, FET's have them intrinsically built in which is another option IRLR024N comes to mind here. Attention to biasing of the base/gate for cut off and saturation, if not proper you can expect a lot of heat dissipation which may lead to thermal runaway in the transistor, so a suitable heat sink should be applied FET's tend to shut themselves down under high temp conditions but not advised. Sorry so short got to go