Audio Amplifier using TIP31c

i had built an amplifier mini for my living room. use two TIP31c, in boxcase says it's 30x2 (stereo). need Transformer 3A 25VCT.

Absolute Maximum Ratings Transistor TIP31

VCBO Collector-Base Voltage :
TIP31 40V
TIP31A 60V
TIP31B 80V
TIP31C 100V

Collector-Emitter Voltage :
TIP31 40V
TIP31A 60V
TIP31B 80V
TIP31C 100V

Emitter-Base Voltage 5 V
Collector Current (DC) 3 A
Collector Current (Pulse) 5 A
Base Current 1 A
Collector Dissipation (TC=25 C) 40 W
Collector Dissipation (Ta=25 C) 2 W
Junction Temperature 150 C
Storage Temperature - 65 ~ 150 C

skema bisa dilihat di Afiata

Mosquito Repellant

I find Mosquito Repellant circuit from Graham Maynard.
Consisting of a phase locked loop (CMOS 4047) wired as a 22KHz oscillator,
The output is further amplified by a pair of complimentary output transistors and drives 3.25 inch Piezo.

amplifier scheme

power-amplifier.blogspot.com/

just visit this blog

Elliot Sound Project

http://sound.westhost.com/
Rod Elliot Sound Project, many scheme here, go visit his page.
i copy this link to my blog for personal use only. i will re-design it to fit in my tinybox. the art of electronic is drawing the PCB :-).
so Do It Yourself, buy the parts, heat with ironsolder, and enjoy electronic hobby...

also he has the Notice :

Copyright Notice. This article, including but not limited to all text and diagrams, is the intellectual property of Rod Elliott and National Semiconductor, and is Copyright © 2001. Reproduction or re-publication by any means whatsoever, whether electronic, mechanical or electro-mechanical, is strictly prohibited under International Copyright laws. The author (Rod Elliott) grants the reader the right to use this information for personal use only, and further allows that one (1) copy may be made for reference while constructing the project. Commercial use is prohibited without express written authorisation from Rod Elliott.

4 LED VU meter LM324

Get Inspire from circuit-electronic.blogspot.com by Tom.
thanks provide us scheme electronic circuits. I want make cheaper, small and humble Audio LED VU Meter. I think that scheme is simple.
I bought IC LM324 only 1500rp (if 1USD=10.000rp so it's 0,15 USD ?)

tone control

i search scheme, and i found tone control. nice, i will build it.
http://circuit-electronic.blogspot.com

4 Watt audio Amp TIP41

here another mini amp

repair sanyo 4505 miniamp

I got mini amp from my bro, hmm it is very old stuff. i must re-build again. poor the PCB , cause pre amp part is cut off. hmm.. nevermind, it is become more small. Fit in my box :-) so i must search scheme again to figure the partlist. here the scheme. i got from www.electronica.ro
Thanks.

Volume Control 4066

Replace than old mono Variable Resistor with digital one. yes i wish i can create an digital Volume COntrol. i bought IC 4060 it's Quad Switch. use R2R Ladder to make some Bridge. For example the level is 0000 binary (all switch off) the output are 0% when all switch on (1111 binary) then the output 100%. We need some Count Up and Count DOwn IC to produce 0000..1111 binary counter. Use 40xx family IC, can use in wide voltage 3,6,12V. the PCB must not over 3x3cm (two IC) with two button, 4 LED binarycode id.

Can you figure out? What about that scheme? come on quick design it, create it and get the photo. put on your web site . then notice me on comment page :-)

Tone Control Schematic

Hmm.. after walk around at google, search something like that
tone control ! to complete my 60W Power amplifier.
yeah that and old amplifier that my big bro give 2 me
u can visit other electronic scheme at
www.uashem.com