I came across this article from an old edition of "Hands-On Electronics". It's a directional microphone amplifier--using a single resonating tube (4" PVC pipe). The amplifier uses a 3" speaker as a microphone, coupled to a TLC272 as the preamp, then a LM386 as the power amp.
Since TLC272's are getting a little tough to find (but they're on ebay BTW), I think a LM1458 could probably work as well.
The PVC pipe is 42" long. That can probably be cut down also. The mic (speaker) is attached to foam for padding.
Looks like an interesting project!
Since TLC272's are getting a little tough to find (but they're on ebay BTW), I think a LM1458 could probably work as well.
The PVC pipe is 42" long. That can probably be cut down also. The mic (speaker) is attached to foam for padding.
Looks like an interesting project!