Posts Tagged ‘RF transmitter’

RF Dual DC Motor Controller

The transmitter circuit consists of WZ-X01 RF module, Holtek HT-640 encoder and 8-bit A/D converter. U1 ADC0804 converts the analog voltage to digital data; U2 encodes that data (D0~D6) along with D6, D7 and transmitting through the RF transmitter module. The potentiometer VR1 varies the voltage to the A/D U1 pin6, since only the lower 6 bits are used; the trim pot VR2 has to adjust so that the maximum input to the U1 will not exceed 1.25V. The S2 (D6) and S3 (D7) are used for controlling the rotation direction of the motors. S1 set the transmitter address; this address has to match with the address of the decoder circuit.

Read More Source:
http://www.wzmicro.com
Thank you.

Related Links
More circuit PWM Speed Motor
More circuit Stepper Motor Driver
More Circuit about Motor Control
More Circuit about dc motor drive
More Circuit about Servo Circut
Stepper Motor Driver using L298 and L297
Stepper Motor Controller by ULN2003
DC Motor Driver with L6203
Touch Motor Control by SCR and Schmitt Trigger
PWM Speed Motor Controller By IC 555
PWM Control Speed Motor 12V By TL494
PWM DC motor control with SG3525
PWM Motor Speed Controller – DC Light Dimmer by IC LM324

TV Transmitter by 2N3904

This circuit from Poptronix allows you to send video to any television in the house. It’s as educational as it is practical. Since it’s from Poptronix, a circuit board layout is included….

Related Links
More circuit RF Transmitter
More circuit TV Transmitter
1 Watt Universal RF Amplifier
VHF Audio Video Transmitter by BF494
TV Signal Amplifier by BFR90, BFR91, BFW92
More about RF circuit

Read More Source:

http://web-ee.com/images/TVTransmitb.pdf

Thank you

3V FM Transmitter for 88MHz to 108MHz by BFR90

The important part of the circuit is formed of the Colpitts type oscillator. C3,C4,C5,C6,CD1-CD2 and L1 determines the frequency. BF982 and dual gate MOSFET are active parts in oscillator. When the input impedance of the MOSFET gate inputs are high, LC tank is not affected. However transistors force the LC tank and cause phase shift. Two driver stages are added to isolate the antenna from oscillator. First stage (BF199) ampifies the low signal of the oscillator and works as a constant load. The second stage (BFR90) amplifies the signal going through the antenna some more. A short copper wire can be used as an antenna here. Attaching a large antenna to this circuit is unnecessary because the output power is low. Notes: 1. Coil 1: Winding wire must be 1 mm thick and isolated. Number of turns: 3.5 . 5mm core must be used and the distance between each turn must be 1mm. 2. You can use BF199 instead of BFR90. 3. If you can’t find the varicap diode, you can use MV104 instead.

Related Links
More circuit about RF
More circuit FM Transmitter
TV Transmitter with BC547
FM Transmitter 4W by 2N3553
FM TRANSMITTER By 2N2222
FM Transmitter with Op-amp LM358
Coil-less FM Transmitter by IC 40106
FM Wireless Microphone
9 Volt FM Transmitter Kit by BC338
FM Beacon Broadcast Transmitter (88-108 MHz)

Read More Source:Link
Thank you.