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HI – FI Stereo FM Transmitter

L1 – 3.5 Turns Variable Coil BA1404 IC 38KHz Crystal ANT – 30 cm of copper wire Whether you want to create your own radio station, transmit the music around the house, or simply create a wireless link between your iPod and a receiver in your car, this transmitter will let you do these things [...]

Vu Meter For Power Amplifiers

R1=See Text and Picture1 IC1=LM3915 D9=Led Yellow 5mm R2=10 Kohms IC2=LM317T [On Heatsink] D10=Led Red 5mm R3=1.2 Kohms TR1=15 Kohms Multiturn Trimmer S1=2dip Switch R4=8.2 Kohms D1=1N4002 J1=3pin 2.54mm step connector R5=680 ohms[2W] D2….D8=Led Green 5mm R6=270 ohms C2-3-4=100nF 100V MKT 5% C1=100uF 25V C5=22uF 25V

Converter 12V DC to 220V AC 50W

R1=10Mohms C4=10uF 16V IC2=4013 R2=100ohms C5=47uF 16V IC3=4047 R3=1.2Kohms C6=470nF 400V CR1=3.2768 MHZ crystal R4=560Kohms D1=5V6 0.4W T1=220Vac/2X10V 2X2.2A *see text R5-6=2.2Kohms D2-3=47V 1W F1=5A Fuse R7-8=56 ohms 5W Q1-2=BS170 F2=0.25A Fuse CX=22pF trimmed capacitor Q3-4=BD139 L1=1H smoothing choke C1-2=22pF ceramic Q5-6=BD249 C3=8.2nF 100V MKT IC1=4060

TV Transmitter with BC547

Circuit avid Kwaku Celestin – Ghana, West Africa Email :mightycelestin@yahoo.co.uk Description: A VHF band TV transmitter using negative sound modulation and PAL video modulation. This is suitable for countries using TV systems B and G. Notes: The frequency of the transmitter lies within VHF and VLF range on the TV channel, however this circuit has [...]

XR2206 Function Generator

Amplifier 50W

IR Detector

Lead Acid Battery Charger

TV remote control Blocker

Just point this small device at the TV and the remote gets jammed . The circuit is self explanatory . 555 is wired as an astable multivibrator for a frequency of nearly 38 kHz. This is the frequency at which most of the modern TVs receive the IR beam . The transistor acts as a [...]

3 Line Mixer

Power Supply +13.8V 5A with LM338

Many times we needed one relatively powerful supply in order to we supply various appliances with + 13.8V, as transceivers CB, charge lead-acid batteries, etc. The circuit it uses known completed that is capable gives in the his exit, current in continuous operation 5A and 12A peak current. It does not only need few external [...]