Datasheet BC337 Philips
http://www.datasheetcatalog.org/datasheet/philips/BC337_3.pdf
 
 

250mW audio amplifier
Here is a very simple three transistor audio amplifier circuit that can deliver 250mW to a 8Ohm speaker.
http://www.circuitstoday.com/250mw-audio-amplifier

3-Channel Audio Splitter
This circuit is suitable to amplify and distribute the audio signals.
http://circuits-projects.blogspot.com/2011/05/simple-3-channel-audio-splitter.html

Active light control by LDR and BC337
This is automatic light circuit when be become dark. It by use LED Lamp, be a place gives the light and this circuit has small-sized use volt supply 3V only.
http://www.eleccircuit.com/light-sensitive-switch-with-ldr-2n2926/

Best 12V battery charger circuit using LM311
The best 12 Volt battery charger circuit our this is a charger circuit automatic system, then when the battery voltage is lower than specified, this circuit provides power to the battery immediately and stops charging when the battery is fully only.
http://www.eleccircuit.com/best-12v-battery-charger-circuit-using-lm311/

Electronic siren circuit
This is a compact electronic siren circuit based on three transistors.This circuit is suitable for in corporating with other alarm or siren projects such as burglar alarms, automatic factory sirens etc or a simple push to on alarm.
http://www.circuitstoday.com/electronic-siren-circuit

High Power Siren Circuit
This article is all about a comparatively strong siren circuit useful for any purpose.
http://www.circuitstoday.com/high-power-siren

Light Relay Switch By BC547 & BC337
This circuit is simple form but can be useful various such as The alarm circuit, an more electronic control circuits such as ON-OFF electrical equipment, the flash light control circuit or etc. following with do you want.
http://www.eleccircuit.com/light-relay-switch-by-bc547-bc337/

Powerful Security Siren
This circuit was requested by several correspondents. Its purpose was to obtain more power than the siren circuit already available on this website (One-IC two-tones Siren) and to avoid the use of ICs.
http://circuits-projects.blogspot.com/2012/10/powerful-security-siren.html

Simple Phono Preamplifier Circuit
This simple but efficient circuit devised for cheap moving-magnet cartridges, can be used in connection with the audio power amplifiers shown in these web pages, featuring low noise, good RIAA frequency response curve, low distortion and good high frequency transients behavior due to passive equalization in the 1 to 20 KHz range.
http://circuits-projects.blogspot.com/2012/06/phono-preamplifier-circuit.html

TV Transmitter Circuit
Here's a simple schematic of a TV transmitter circuit or video transmitter circuit which is able to broadcast on VHF between 60 to 200 MHz. The input video can be from any CCD camera and VCR.
http://www.circuitdiagram.org/tv-transmitter-circuit.html