Page 1 of 1

PIC FreqOut to a speaker

Posted: Wed Apr 21, 2010 11:09 am
by Yerry
Kids have their Parallax PIC playing the Chicken Dance. Oh Joy. Fortunately, with the transducer included in the kit, it's barely audible. Well, they want it amplified somehow.

WHAT AM I ASKING?!?!?!?! Is there a simple way to hook up a transistor like a 3904, 2222, or 4401 (which I have) withy one or more cheap speakers (perhaps in series to get the impedance up and load down) without having to mail order amp chips and wait, wait, wait?

Re: PIC FreqOut to a speaker

Posted: Wed Apr 21, 2010 3:14 pm
by CeaSaR
Yerry wrote:Kids have their Parallax PIC playing the Chicken Dance. Oh Joy. Fortunately, with the transducer included in the kit, it's barely audible. Well, they want it amplified somehow.

WHAT AM I ASKING?!?!?!?! Is there a simple way to hook up a transistor like a 3904, 2222, or 4401 (which I have) withy one or more cheap speakers (perhaps in series to get the impedance up and load down) without having to mail order amp chips and wait, wait, wait?
Read this thread. I think you can find something there you can use. As a matter of fact, the initial linked design
can get more audible if you push the impedance up to 32 or 64 ohms. And it runs on 3 volts. If you want any
changes, let me know. I can change things pretty quick (voltage changes, etc.), but the final design wants at
least 9V to work properly. I could steer you to other designs from Bob and Robert, but they require opamps to
work. If you have to order them, you might as well order some LM386's to play with instead (for the kids, that is :mrgreen: ).

CeaSaR

Re: PIC FreqOut to a speaker

Posted: Thu Apr 22, 2010 7:47 pm
by dacflyer
the 386 amp is a great cheap idea, very little parts needed to get it going. and you can get it at radio shack. , easily runs on 9 volts , and most any small speaker.
have a look at this.. says it can work as low as 4 volts
www.tzywen.com/modules.php?name=News&file=art...

and or this... http://www.national.com/ds/LM/LM386.pdf

good luck.

Re: PIC FreqOut to a speaker

Posted: Tue May 04, 2010 7:53 pm
by Yerry
FINAL RESULTS!!!!!

State Tournament was this past Saturday (May 1). They had found a 100-ohm speaker, and had serout drive a 2N2222 transistor. Worked great. Gotta admit, it was the crowd favorite. There was a 6-way (or more; still waiting on factual details) tie for first, and when broken, my kids had a 4th. One of my team's better efforts by far, result-wise.

Re: PIC FreqOut to a speaker

Posted: Tue May 04, 2010 8:59 pm
by CeaSaR
Excellent! Got any photos or schematics of the final setup? Would love to see how you put it together.

Next year, 1st place!

CeaSaR