Rechargeable 9v as power source?

[Scottyzedinosaur]

Hey everyone, quick question.
I have a phr and rkcstr microdrive v3 ive set at 120mA.
I've heard 9v batteries suck as power sources. Would a rechargeable 9v work?... It's 170mAh. Which isn't great, but I'm on a pretty tight budget, and can't afford a flashlight host. I'm using a project box. If this won't work, any other suggestions?

Any help is appreciated, sorry about ze noob questions. It's my first build. Thanks

 

[jenner6989]

im having the same prob. i have a phr labby and it had a 9.6v 1700ma i think and it took a shit. wont hold a charge. i ws thinkink about an rc recgargeable 9.6 v. but idk what ma?

 

[Pontiacg5]

A 9V rechargeable will not last very long at all. You should get a 6 cell AA battery holder if you can't get lithium batteries. They are like 3 dollars at radioshack.

The RC rechargeable 9.6V will work. Those are usually a pain to charge though.

Make sure you reset the driver current if you increase the input voltage when using a linear driver!

 

[chipdouglas]

well look at it like this.... if you have a 9 v battery that is 170mah it will last for approx over an hour of continuous use. not too bad but not great.

michael

 

[Eudaimonium]

Make sure you reset the driver current if you increase the input voltage when using a linear driver!

What?!

:tsk::tsk:

Output current is NOT affected by input voltage. Evar.

Could you be connecting your linears in oppsite polarity? Negative batt on In pin?

Resembles the problem.

No matter how many volts you put in, you still have same output milliamps.
Difference is heat-up on main IC. Extra voltage is burned off as heat.

 

[Scottyzedinosaur]

well, i double checked my driver anyway. it said 120^^ and yeah, they take forever to charge. but i bought 2, so ill have one on the charger and one in the laser.

 

[Scottyzedinosaur]

Plus, this laser won't be seeing heavy use. It'll be just a show-off laser. Like "hey, I built this." If I really want to burn, I'll just whip out ze infrared or ze red