Communicator | Electronic Project Circuits

Posts Tagged ‘Communicator’

Ultrasonic Pest Repellent by CD4013

It is well know that pests like rats, mice etc are repelled by ultrasonic frequency in the range of 30 kHz to 50 kHz. Human beings canâ€™t hear these high-frequency sounds. Unfortunately, all pests do not react at the same ultrasonic frequency. While some pests get repelled at 35 kHz, some others get repelled at 38 to 40 kHz. Thus to increase the effectiveness, frequency of ultrasonic oscillator has to be continuously varied between certain limits. By using this circuit design, frequency of emission of ultrasonic sound is continuously varied step-by-step automatically.

Original source:http://www.radioland.net.ua/electronic-circuit-id-29.html

Be the first to comment - What do you think? Posted by admin - October 27, 2008 at 6:10 am

Categories: Digital, Electronic Control Tags: Communicator, IC 4013, Ultrasonic

LED Tone Generator by IC LM555

This circuit use test waves light receiver signal pulse change LED1. For R1 and C1 be formed control the rate pulse of the circuit. Besides equipment all value in the circuit will give the rate pulse about 600Hz. Other detail see add in the circuit.

Be the first to comment - What do you think? Posted by admin - August 15, 2008 at 9:32 am

Categories: LED Flasher, Lighting Tags: Communicator, LM555, Tone Generator

RF Modem by XR2211 – XR2206

This is a project based on the above chips , details of which were sent to me by VU3CRJ. I have designed a PCB for the same but unfortunately I have not tried it out. It is to be used with the Baycom Software for Packet Radio. The software is available at the homepage of Harry Lythall. Earlier I have successfully built and sold Amateur Radio Modem using the AM7910/1 to local HAMs but unfortunately the chips went out of circulation. The above combination of XR2211 / XR2206 turns out to be much more cheaper and simpler. The circuit diagram of the project is shown below.