December 09, 2009

Homebrew PLL for HF Band

This is a PLL design that have been tried and works well for HF bands,
based on this design can be developed more PLL for frequency other band

1. Because this PLL works at 100 Hz step, it created the first reference frequency 100 Hz. Circuit that handles it is UNIT CLARIFIER, IC2, IC3, IC4 and IC5 is fed to the Comparator pin3. CLARIFIER produce 6144 MHz frequency changed by a digital signal IC2, IC3 divided by 4069 and divided again by 15 by IC4 thus obtained frequency 100Hz.
2. PLL design is the issue of output 5.5 MHz to 6 MHz.Output of VCO strengthened in addition to output, some output is inserted into IC1 Pin 4 to be mixed with the xtal oscillator frequency. The results of this mixing the difference is taken and converted into digital signals by the IC2 and fed to the IC19 (4059) called programmable DEVIDER.
3. In this project we design so that it is in the ON PLL's output frequency
5.7MHz. (Please design something different). The output of the mixer IC1 Pin6 is 6144 - 4440 = 5.7 Hz, which is then fed to the PROGRAMMABLE IC10 DEVIDER Pin1 for 4440 divided by the number 100 to get the results hz on pin 13. The output from IC 10 pin 13 is fed to the IC Comparator 5. Because IC5 receive 2 same frequency 100Hz then the IC 10 will be LOCK marked with LED flame. Pin output of Comparator 13 is a a constant DC voltage and fed to the varicap diode at 209 MV VCO. Thus the PLL out will also be constant or stable at 5.7MHz to Comparator LOCK, so that the output of IC5 is a DC voltage a constant and flat. This DC voltage is fed to the VCO so that the PLL stable at 5.7MHz frequency.
4. To program the IC 10 to divide the 4440, conducted via UP / DOWN
consisting of counter IC6, IC7, IC8 and IC9, which each have Pin 4, 12, 13 and 3, which is used to enter the program. If PIN2 is given 9-volt voltage will have a weight like a table in the schema, while the foot that the weighted ground ZERO.
5. In this project programmed IC 6 weight 4, then 4000, weighing 7 IC 4 means
400, IC 8 weighted 4, means 40 are IC9 weighted 0, so the value of the program is = 4000 + 400 + 40 + 0 = 4440. (try it with other programs)
6. Dial Encoder with all its components to move the value of the program
which is the UP / DWN counter so that the PLL to walk up / down.

Reff. Supardi yb3dd.

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