Bob's DIY Homebrew Projects
do like to build stuff. I also like to share project details and
give away finished projects (like kits and coasters for use as door
prizes at our club meetings, for example). And, in the true sense
of open source, I like to benefit from those before me and pass on
information to those that follow. So, for anyone who is the least
bit interested, here is a starting point for a collection of projects
that I have done. Enjoy!
AD-8307 Power Meter
use this little power meter in series with a 5 Watt 30 dB attenuator to
measure final output power on HTs, QRP rigs, and the like. The
noise power sits at about -70
dBm and the maximum input power is about +17 dBm, not a bad dynamic
range for a unit in an Altoids box! The board layout is done
using the free version of Eagle (cadsoft.de) on my Linux box; files for the board, schematic, photograph, and a reference to the design article from QST follow below.
(Note: the label on the photo above should read AD8307 and not ~97)
little circuit is used with an oscilloscope to find fault locations in
long transmission lines. This was just another fun little project
the happens to fit in an Altoids tin. The relevant files are
linked in below.
If you have never taken a look at the web site of Paul Wade, W1GHZ, located at http://www.w1ghz.org/small_proj/small_proj.htm then you are missing out on some great information. I built the electronic load he documents at http://www.w1ghz.org/small_proj/ps_load.zip
and have been using it ever since. Thanks, Paul! Here's a
photograph and the document I generated for our local club, NFARL, that
describes the project: DIY_elec_load_02.pdf.
Low-Cost Paddle for the FT-817
designed a little paddle for use with the FT-817. When used with
the internal keyer, this little gadget works just fine. The idea
here is to simplify, simplify, simplify -- by doing this the parts are
cheap and the function is straightforward. Paddle pieces are cut
from a single piece of single-sided paper-epoxy circuit board.
This board material is much easier on the 0.040 inch end mill
used to cut out the pieces than is a glass-epoxy board. This
project is done on the CNC minimill, of course -- it even cuts the
mounting holes. A piece of Corian is machined to mount the paddle
to the 817 using the carrying strap holes -- and, you can still use the
strap. Here are some photographs of the paddle.