Remote Control

This encoder can generate up to 19,683 codes from 9 address lines by detecting 1,0, or open circuit. To initiate the transmit sequence, pin 14 should be pulsed low. The encoder will now output on pin 15 a data stream representing the condition on each of the address/data pins in turn and then repeat the operation, so that two complete identical words are transmitted. If pin 14 is held low, the output will be continuous, otherwise two identical words are output for each.....

Views: 1272 | Votes: 44 | Comments: 0 | Rating: 9 | Rank: 10 | Added: Mar 15, 2013 |

A GC Electronics P/N J4-815 transducer is used to receive 40-kHz acoustic remote-control signals...

Views: 17 | Votes: 29 | Comments: 0 | Rating: 2 | Rank: 5 | Added: Feb 18, 2013 |

The circuit is built around the LM567 tone decoder IC that requires about 100 millivolts at its operating frequency. The frequency is set by a 10 K variable resistor and can be between 700 and 1500 He..

Views: 551 | Votes: 109 | Comments: 0 | Rating: 9 | Rank: 5 | Added: Jan 24, 2013 |

A signal from an IR remote control is converted from IR radiation to a frequency pulse that can be transmitted tlirough coaxial TV cable or any other two-conductor wire to another room,..

Views: 15 | Votes: 47 | Comments: 0 | Rating: 3 | Rank: 5 | Added: Dec 27, 2012 |

This circuit can be used to operate a VCR or CD player from another room. It"s really an infrared signal repeater. The s..

Views: 18 | Votes: 15 | Comments: 0 | Rating: 2 | Rank: 5 | Added: Dec 24, 2012 |

This 1-cable system carries composite video (NTSC, PAL, or SECAM), power, and channelselect signals. The interfa..

Views: 24 | Votes: 93 | Comments: 0 | Rating: 4 | Rank: 5 | Added: Nov 8, 2012 |

This transmitter sends an FM signal in the 88-to 108-MHz range, with a tone of 19 kHz. This can be used to activate the FM MPX pilot carrier indicator, which can be interfaced to external devices. L4 is for use with a 15 CM wire antenna. LI is 9 turns of #26 enamelled wire on a 54-W 10-kQ resistor (carbon type), L2 is 2 turns wound over LI. ..

Views: 24 | Votes: 71 | Comments: 0 | Rating: 0 | Rank: 5 | Added: Oct 27, 2012 |

Shown here arc several possible interface circuits that can be used with the remote-control transmitter. The one in A illustrates a typical FM stereo MUX decoder with a load connected directly to the open-collector output of a TA7343 PLL. The circuit in illustrates an optoisolator- coupler output driving a 12-V relay coil via a general-purpose transistor. C shows the gate of an N-channel power MOSFET connected to the output of a 4N33...

Views: 15 | Votes: 74 | Comments: 0 | Rating: 4 | Rank: 5 | Added: Sep 28, 2012 |

The IR Tester circuit lets you know if the button you press on a remote control is working...

Views: 8 | Votes: 105 | Comments: 0 | Rating: 8 | Rank: 5 | Added: Jul 22, 2012 |

A schematic diagram for the remote analyzer is shown. The circuit is powered from a simple 5-V supply, consisting of PL1, SI, Tl, a bridge rectifier (comprised of D1 through D4), capacitor CI, and a common 5-V regulator, Ul. Switch SI is the on/off control and is optional. The power-supply transformer used in the prototype is a 12.6-Vac unit, but any transformer that can supply at least 5.6-Vac will do. The 12.6-V unit was used solely because of its availability. The.....

Views: 10 | Votes: 58 | Comments: 0 | Rating: 0 | Rank: 5 | Added: Jul 10, 2012 |

Using a battery, a phototransistor and a visible-light LED, this simple circuit is a " "go/no go"" tester fo..

Views: 6 | Votes: 80 | Comments: 0 | Rating: 7 | Rank: 5 | Added: Jul 3, 2012 |

This circuit is based on the Sharp GP1U52X IR module and 1NS8048L microprocessor. ..

Views: 21 | Votes: 1 | Comments: 0 | Rating: 5 | Rank: 5 | Added: Jun 29, 2012 |

This transmitter can be used for a variety of purposes. An INS8048L microprocessor generates various codes depending on keypad presses. The codes are modulated on a 40-kHz carrier...

Views: 16 | Votes: 12 | Comments: 0 | Rating: 2 | Rank: 5 | Added: Jun 21, 2012 |

The transmitter is built around two CMOS 555 timer ICs (TLC 555s). The transmitter generates a modulated 35-kHz ..

Views: 18 | Votes: 101 | Comments: 0 | Rating: 0 | Rank: 5 | Added: May 24, 2012 |

A simple and effective receiver for actuating garage doors, alarms, warning systems, etc. The SCR, which has a very low trigger current 30 µ is typical—it requires an input power of only 30 juW to activate the relay. A high Q tuned antenna circuit assures rejection of spurious signals. A whip or wire antenna is adequate up to 100 feet from a low power transistor transmitter. ..

Views: 707 | Votes: 70 | Comments: 0 | Rating: 1 | Rank: 4 | Added: Apr 19, 2012 |

This circuit provides power control without running line-voltage switch leads. The primary of a 6-volt filament transformer is connected between the gate and one of the main terminals of a triac. The secondary is connected to the remote switch through ordinary low-voltage line. With switch open, transformer blocks gate current, prevents the triac from firing and applying power to the equipment..

Views: 5718 | Votes: 89 | Comments: 0 | Rating: 7 | Rank: 5 | Added: Apr 2, 2012 |

The transmitting section of this infrared tx-rx is unusually simple but it works rather well: the infrared LED pulses at a frequency of 160Hz and its range, with its receiver, is between 2 and 4m depending on the transformer used and the setting of the 100k pot. With other receivers it may reach a range of 15m, without any lens but with a perfect alignment between tx and rx. The receiving section uses an infrared phototransistor and an additional infrared emitter is placed.....

These units can be useful as a short-range, single-channel remote-control. When the pushbutton in the transmitter circuit is briefly activated, the LED D1 in the receiver illuminates and an optional beeper or relay can be operated. Circuit operation is based on a non-modulated 35KHz frequency carrier transmitter, and on a high-gain two-stage 35KHz amplifier receiver, followed by a frequency-voltage converter and DC load driver...

This circuitry offers some features that are highly desirable when building a QRP (or ANY) transceiver. It also includes a combination of features that many might not always take the time to include in their projects. Considerable effort has been made to assure that in this design, the RIT (RX frequency offset control) voltage and the TX frequency offset control signals are immune to supply voltage variations. IC1 requires a regulated +6 V voltage for proper operation......

These ultrasonic circuits are all quite old: my notes date them at mid-70s so they don`t use ICs. Nevertheless there are several places where an op-amp would possibly simplify things. Despite their age I hope they are of interest: certainly basic principles don`t change. This transmitter is designed to work with the next circuit as a remote control transmitter/receiver. It is only a single channel and you could once get multi-channel chips for the whole job. However.....