The top circuit board, above, is the receiver section from Part I of my latest project which is aimed at those who are new to Ham Radio or new to "homebrewing' their own radios. The complete project is in a two part article, the first of which appears in the Spring 2011 Issue of QRP Quarterly and covers the building of the receiver plus some of the test equipment necessary to get it up and running. Part II is the transmitter portion and is also shown above.
Basically when the project is finished you will have a 5 Watt, 40M QRP CW Transceiver that is VXO controlled, has a narrow crystal filter and tunes 30 KHz of the 40M CW band including the two popular QRP frequencies. The cicruit is comprised of well proven building blocks and the method employed in the article is to build and test as you go. This provides a means to identify, isolate and correct a problem before proceeding onto the next stage. Great pains were taken to insure that all of the detail is covered so that the build will be successful from the outset. Part II is slated for publication in the Fall 2011 Issue of QRP Quarterly published by QRP ARCI (www.qrparci.org)
There were several goals in the development of this project. One of them was cost so that no single part would cost more than $2. With the exception of two parts that goal was achieved. Second was that it would offer high performance without the use of arcane and mystery circuits. Third was ease of construction so the one didn't need an advanced degree in solid state physics just to build a receiver.
For those who would like to see the detail of the design process for this project I have documented the various steps and design considerations. You can download that document here.
This page has been set up so that more detail of the schematics can be seen than might be available in the printed article and also includes two parts lists. One list is set up so that all of the parts for a specific buidling block complete with the part numbers and the identified supplier are available to the builder. The QRP Quarterly editor asked me to limit the parts acquisition to just a few suppliers so that shipping charges could be minimized. I did that. A second cut of the parts list is to identify all parts associated with a specific supplier. Since these lists are in Excel format --it will be possible to cut and paste the list right into the supplier's order forms.
The real build information is in the article so you will need to join QRPARCI and get a subscription to the QRP Quarterly so that you can read the step by step build and alignment processes.
73's de Pete, N6QW, May 2011