The beacon controller is intended to be operated for telemetering data available on board of the VUSAT in Morse code so that the ham radio operator can decode the info without any costly and complex equipment. The design strictly follows the KISS concept. It uses low cost, easily available components through out the design. A block diagram of the
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beacon controller is as shown: The controller can accept 16 single ended data channels of which the dc level represents the parameter to be telemetered. These channels are selected one by one (multiplexed) by using 2 number of CD 4051 (analog MUX). Voltage from selected channel is given to the ADC chip for converting this voltage to its digital equivalent. A channel counter (4-bit binary counter) controls the channel selection. This counter counts every clock pulse given to it and thus gives a 4 bit binary output. This binary is given to the analog mux as address of the channel to be selected. For every clock pulse to the counter, successive channels are selected. The channel select clock is derived from the end of message signal (EOM), which will be explained later. ADC chip used is AD7574. This chip is an eight bit Successive Approximation type ADC made by `Analog Devices`. This ADC starts converting the analogue voltage input when the RD! signal goes low and the digital value is available at the output pins approximately 15 microseconds later. RD! signal is derived from the "EOM" signal available from the EPROM. Eight-bit Binary output from ADC is given as the address of 8 most significant bits of the EPROM through two nos. of quad 2 input multiplexer chips. This two chips form an 8 bit 2 input multiplexer, one input is being the 8 bit binary from ADC and the other being the channel address (4 LSBs the upper nibble are...
This project fits more for custom made battery casing that can have more space to hide things inside. This switch with few alterations can be used for any other project as well but is designed based on e-bike needs! This project use a clever functionality of....
The circuit described here uses ultrasonic oscillations and operates based on the propagation velocity of these oscillations in the air. Thus, we can easily determine the distance of two points if the time within which the wave travels this distance is....
Sometimes the precious metals are hidden too deep and are not detected except with complicated devices. In many cases, however, small pieces of precious metal buried near the surface can be detected by relatively simple means. Everyone is very attractive to....
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The principle behind a metal detector is really very simple. Proof of this is the circuit that follows, in which it proves that the construction of a metal detector can be done in the minute, with few components that we find very easily everywhere. With the....
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In the past the sounding (sea bottom measurement) was done with the "bullet", that is, with a heavy lead object that the seamen plucked into the sea hung from a calibrated rope. As soon as the "bullet" reached the bottom, the depth appeared directly from the....
This Amplifier was designed to have the following specifications: Distortion less than 0.1% at full power of 100W even at 20KHz. Power has to be attributed to an extended bandwidth. The output transistors must be protected against short circuits. The power....
A series of LEDs serve to alert the gardener when plants need water. Using two conventional digital integrated LEDs and a series of LEDs, we make a very useful device for gardening. The device detects the amount of water in the pot and alerts the grower.....
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