FF998JZHHS9ROJ1.LARGE_.jpg (40546Bytes)
TDA2003-10W-Power-Amplifier-for-Car-Audio-System.jpg (18943Bytes)
Hello everyone,I want to build a system so that when I talk over a tiny electret mic,my voice gets amplified and comes out of a speaker (I dont know what are these systems called , Police use them to alert,announcers use them too). All I've done so far is that I've built an electret mic preamp out of BC xxx transistors,and a 10W power amp out of TDA2003 IC. BOTH are running great individually. But whenever I connect the output of the mic to the power amplifire stage,it doesn't work anymore...And in addition to that there are feedback oscillations too. Can any one direct me to any schematics? Is there any way? The thing should be portable and compact.. Thanks for any reply.