A PIC16x84 processor may be used to generate a PSK31 or FSK31 signal. This could be used for beacon transmissions (as described here) or they may be used for telemetry, experimental, or even QSOs - the latter being true if you are willing to put up with a few `quirks`:-) The PSK transmitter was originally designed back in 1999 - originaly for the now-discontinued PIC16C84,
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but later updated for the PIC16F84 which is still available. Since then, however, a large variety of newer PICs have been released that could be used to significantly expand the capabilibities and performance of this unit - but I`ve not done so. Since the source code is available to all, "porting" it to one of these new chips would be pretty easy. This is the question that I asked myself. While my HF rig is capable operating in the MedFER frequency range, it seemed foolish to tie it up in this fashion, and it would tie up an entire computer/sound card/ect. Having operated beacons in the past, I feel that the lower the "hassle factor" involved in operating the beacon, the more likely it is that you will keep it on the air - and that is the entire purpose of even attempting to operate a beacon. When I decided to put a PSK31 MedFER beacon on the air this time around, I decided to follow my previously-established philosophy: I wanted a beacon that could send a message in PSK31, and just work when plugged in. To generate the PSK31 data, I decided to utilize the now-ubiquitous PIC processor and incorporate it with other fairly simple circuitry. (As for the question of "why operate a beacon, anyway " - I don`t really have a good answer. Take a look at the "CT" Lowfer Beacon archive page for a possible insight as to the psychology of it all. ) Version 1. 0 provided simple beacon operation, simply playing its message out of EEPROM....
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....
Many times for various reasons we forget or can not water the plants that we have in our homes. And many humidity sensors units just notify us with a beeping sound or with a flashing light, that the pot needs watering. But what if we are away from home? This....
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....
The sub-harmonic bass generator is a sound producing unit for guitars. The sound it produces looks very much like that of the bass guitar. The octave generator is sometimes quite unusual since it does not produce any of the usual ways of coloring the sound,....
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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