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What Frequency Beacon is?
The frequency beacon in my presentation is a small board with Schmitt Trigger, Divider, Counter and a Microprocessor, you can put into your RIG. It counts frequency and generates appropriate telegraphic signal to the audio path telling you, what frequency you are tuned to.
What it is good for?
In direct conversion radios, where we tune the main oscilator frequency, we may get information of position on the scale without looking at it. It is good, when we are outside in fields and are limited with power and light.
How it works?
It is employed in two modes controlled by small push button on the front pannel of the radio. By default it is set to a mode, where going e.g. from a frequency of xy9 kHz to x10 kHz generates "beep-beep"(two "dots"), while in change from x10 kHz down to xy9 kHz only "beep" (one "dot"). By change of frequency you get this information every tenth of kHz. The letter y presents tens, x hundereds.

The frequency beacon also gives you the idea of accurate frequency better than in tenth of kHz. Between the "beacon" frequencies you can get information of exact frequency by short push (shorter than 500msec) and processor will telegraficly play frequency in kHz, e.g. frequency is 7.018kHz, than you will hear ( - .---- ---.. Zero up front of numerics is presented as a dash) By longer push than 500msec you can turn your frequency beacon ON/OFF.
Frequency beacon is simple readout which not only in dark or at night can inform about acurate frequency. It is designed so, that it works up to 36MHz.
Mode Setup
Programming mode you will select by longer push than 500msec. After release the Frequency Beacon will play "R" and you may select the distance between beacon marks. Short push rotates selection from 10 to 5, 2 and 1kHz. Longer push confirms selection by giving you "+" in your headphones. 
You can turn your frequency beacon ON/OFF with different push lenght on the button. Programming mode is indicated by LED ilumination. When it lights, it is active.
Microprocesor program
The Software for the Atmel procesor was written in C language and for easy use is compiled to HEX format. It is ready to be downloaded and than you can program uP through ICP port.  Feel free to download it from here  please click here
Schematic drawing and PCB
On the schematic of a frequency beacon  is shown, how it works.
The oscilator with a single NAND has an external crystal of 10.245MHz. Reference frequency is feeded into the 8 pin microprocessor ATMEL AT90S2343. The NAND GATE amplifies signal comming from the meassured oscilator. The divider by eight follows and feeds it on input PB2.
The push button is connected to PB1. The PB0 is output with audio signal to be tight to audio output.
The board is powered from stabilised +5V. Its current consumption is about 15mA.

The PCB is designed for SMD components.  Top layer and  components silk screen are in pdf format in 1:1 ratio and masks are free to use. Please note, pictures are in the middle of the page.

Building of the Frequency Beacon takes about three hours to put it toghether. If you are not familiar with SMD, do not be bothered. You can ask me for a KIT or for an assembled SMD on the KIT