Rongge

Make a line follower robot can be done with two transistors. Line Follower Robot series is one of the two transistors contor robot line follower circuit is in Bagun with two NPN transistor and the motor driver as well as processing of sensor signals. In the circuit of line follower robot consists of two parts of the same, only different functions for the motor driver the right and left. Sensor circuit of line follower robot uses the LDR and LED. LDR sensor sensitivity can be set with the VR 10 is mounted in series with the LDR. For more details, see the following figure. Line Follower Robot series 2 Transistor The working principle of the motor driver circuit between the right and left together, when the LDR get the reflection of light from the LED LDR resistance will decrease and make the transistor saturation and motor gets supply and rotates so that the robot moves forward. So at the moment is not the case then the motor did not get a supply, for example, only one sensor is exposed ...

POWER TRANSISTOR Power transistors have controlled turn-on and turn-off characteristics. The power transistors are mostly used in the switching mode. In fact, their applications in motor control circuits are becoming more and more popular. The transistors when used as switching elements, are operated in SATURATION REGION, resulting in a small on-state voltage drop. Power transistors are becoming a viable alternative to thyristors. When power transistors conduct an appreciable Current, the forward voltage drop is in the region of 0.3 to 0.8V. Therefore the power loss in a power transistors is lower than that of thyristors. The switching speed of modern transistors are much higher than that of thyristors and are extensively used in dc-ac and dc-dc converters, with inverse parallel connected diodes to provide bidirectional Current flow. However, the voltage and current ratings of power transistors Available at present are not as high as those of thyristors and Therefore, transistors are ...

Warning: Take care with transmitter circuits. It is illegal in most countries to operate radio transmitters without a license. Although only low power this circuit may be tuned to operate over the range 87-108MHz with a range of 20 or 30 metres. Circuit Diagram  Notes I have used a pair of BC548 transistors in this circuit. Although not strictly RF transistors, they still give good results. I have used an ECM Mic insert from Maplin Electronics, order code FS43W. It is a two terminal ECM, but ordinary dynamic mic inserts can also be used, simply omit the front 10k resistor. The coil L1 was again from Maplin, part no. UF68Y and consists of 7 turns on a quarter inch plastic former with a tuning slug. The tuning slug is adjusted to tune the transmitter. Actual range on my prototype tuned from 70MHz to around 120MHz. The aerial is a few inches of wire. Lengths of wire greater than 2 feet may damp oscillations and not allow the circuit to work. Although RF circuits are best constructed o...

OPERATING MODES OF TRANSISTOR Commonly a Transistor has two junctions (Emitter-Base and Collector-Base Junctions), and each of these two junctions may be either Forward Biased or Reverse Biased . Therefore, there are Four Possible configurations can be made to bias these Junctions . Accordingly transistor may operate in different conditions. It is easy to understand the various configurations of Transistors and the region of operation by take a look on the Tubular Column. sl.no. Biasing Condition Emitter Base Junction Collector Base Junction Operation Region 1 Forward-Reverse Forward Biased Reverse Biased Active 2 Forward-Forward Forward Biased Forward Biased Saturation 3 Reverse-Reverse Reverse Biased Reverse Biased Cut-off 4 Reverse-Forward Reverse Biased Forward Biased Inverted 1. Forward-Reverse Biasing It is the normal biasing of a transistor in which the EMITTER-BASE Junction is Forward Biased and the COLLECTOR-BASE Junction is Reverse Biased. This ...

This is a unique flasher circuit employing a single driver transistor that takes its flash-rate from a flashing LED. The flasher within the photo is 3mm. An ordinary LED won't work. The flash rate can not be altered by the brightness of the high-bright white LED will be adjusted by altering the 1k resistor across the 100u electrolytic to 4k7 or 10k. The 1k resistor discharges the 100u in order that when the transistor activates, the charging current into the 100u illuminates the white LED. If a 10k discharge resistor is used, the 100u isn't absolutely discharged and therefore the LED doesn't flash as bright. All the components within the photo are within the same places as within the circuit diagram to make it simple to envision how the components are connected. The circuit uses a flashing LED to flash a super-bright 20,000mcd white LED