that modulator circuit is pretty sweet! considering that it wont take too much space either... There's always gonna be a problem with battery placement though.. i might use an old cell phone battery since they are rechargeable, compact, light weight and last long... plus if it is a considerably new battery from an old used phone, you can pretty much call that free.

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transistance is futile...

 

Charge the lithium battery properly so it doesn't catch on fire. Add a low voltage disconnect circuit because if it is discharged too low then it is destroyed.

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Uncle $crooge

 

thank youuu.. finally