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In this page you may find some homebrewing projects proposals.
I hope it will be possible to add other projects, mostly relying on the co-operation of all the interested people.
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cwdec2_qst.jpg (269280 byte) Although designed primarily for learning CW, new and experienced CW ops are sure to like this simple and inexpensive CW decoder.
It makes use of a  PIC16F84 microprocessor and a NE567 PLL as analog interface. The software automatically adapts itself to the incoming CW at speeds between 5 and 30 WPM.
It has been published on QST and gained the cover here reproduced.


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A PIC16F84 based programmable micro-counter, the ideal complement for your last QRP transceiver. It may read frequencies over 40 MHz and needs only 15 mA of power supply. It is also possible to connect a prescaler, in a word.... it should be a pity not to build it 

PIC_FREQ (PDF FILE - 60 Kbytes)

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qrp1_40.jpg (33655 byte) A simple CW QRP Transceiver for the 40 meters band. The TX and RX sections are independent modules and may be built separately. Among the main features are :
5 W output power, Full break-in,  superetherodyne receiver, four crystals ladder filter, full coverage of the band with a varicap controlled VFO and SSB reception capability.

QRP 40 m (PDF FILE - 100 Kbytes)

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qrp20_1.jpg (37232 byte) A 20 meters CW QRP Transceiver.
Only a little more complex RIG, but  you'll find  again RX and TX independent modules.
Main features :  5 W output power, Full break-in, superetherodyne receiver with Mosfet RF and mixer stages, four crystals ladder filter, AGC and CW band coverage with   a conversion varicap controlled VFO.

QRP 20 m (PDF FILE - 100 Kbytes)

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dds.jpg (212136 byte) A 'last generation' VFO wich makes use of the DDS technology. It is equipped with an AD7008 DDS from Analog Device and an  ST62 microprocessor from Thomson, the frequency and the tuning step are showed on an LCD display. An ideal gear for your next professional transceiver.

VFO DDS (PDF FILE - 300 Kbytes)

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A "partial synthesis" VFO using the PLL technique, if you want to abandon the classic "free" VFO, but without excessive troubles, this project is for you.

PLL VFO (PDF FILE - 100 Kbytes)

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A simple frequency reader you may employ with a classic conversion VFO or to replace the mechanical tuning in some old RIG

CMOS Reader (PDF FILE - 120 Kbytes)

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designed by Francesco Morgantini IK3OIL