Subject: So You Want to be a Builder, Huh Part 4
Date: Mon, 12 Aug 2002 22:30:09 -0700 From: "Doug Hendricks" <ki6ds@dospalos.org> To: "Low Power Amateur Radio Discussion" <qrp-l@Lehigh.EDU> This is part 4 of a series of articles that I am writing on how to become a builder of
qrp ham radio gear. I plan on going from a rank beginner to advanced projects and giving
suggestions on how to become a good builder. This installment will cover a couple of
projects that are very important station accessories, a set of PC Board Paddles, and the
NorCal BLT Tuner. First the paddles. I have a good friend, Dave Gauding, NF0R, who loves to build simple
gear. He has messed around with building simple paddles for as long as I have known him.
He also has a set of very nice Brown Brothers paddles, yet he continues to experiment
because he likes to build, and it gives him pleasure to build a project and have it turn
out. When Dave saw the PC Board paddles on the NorCal page, he told me that they were the
real deal and worked surprisingly well for such a simple idea. The key to the paddles is
that it uses PC Board for the arm of the paddle, nothing new with that, but the unique
thing is that the board is given more flexibility by drilling a hole in it. Check out the
drawings and pictures on the NorCal page and you will see what I mean. Here is the URL: http://www.fix.net/~jparker/norcal/paddle/nb6m.htm
Wayne McFee, NB6M, designed these single lever paddles, and they work brilliantly. The
NorCal page has a full set of instructions on how to build them, all that you need is some
double sided PC Board and a good iron. I use my soldering station and turn the heat up to
850 degrees and it works fine. You can also use a Weller soldering gun, which will provide
plenty of heat. One of the things that often happens in ham radio is that one guy will
come up with a good idea, and someone else will improve it. That happened in this case.
Carel Mulder, PA0CMU decided to make a set of iambic paddles using Wayne's method, and he
was very successful. Here is the URL to see the double lever iambic paddles. http://www.fix.net/~jparker/norcal/paddle/pa0cmu2.htm
Carel even shows you a simple way to put silver contacts on your paddles. This is a
neat one evening project, and when you finish, you have a nice set of paddles to use with
your station. Seabury Lyon, who lives in the Northeast, showed me a neat trick at
Lobstercon. Seab likes to use something called poster stick, which is also called blue
tack, to hold his paddles on his rig. Gives it a nice solid base, it doesn't move around,
and is always handy. You can buy it at Staples or any office supply store. And, just in
case you are wondering, that is ribbon cable being used as a cord for the paddles. Another
"freebie" and a great idea. The neat thing about this project is that it is
almost free to build. One hint, be sure to use steel wool to polish your pc board before
you solder it. It works a lot better that way. Also, when you have to drill holes in small
pieces it is better to drill the holes first, then cut off the piece from the larger
piece. No kit is available for this one, so you get to scrounge the parts yourself. Ask
around at the next radio meeting for help in finding the parts, or better yet, go to a
swap or flea market and look for old relays and double sided pc board pieces. If you live
near a PC board fabrication shop, ask them for their waste pieces and they will be glad to
give you all that you need. The next project is the NorCal BLT tuner which is a bargain at $25 + $4 shipping and
handling from me. Here is the URL on this project: http://www.norcalqrp.com/blt/blt.htm
This tuner was designed by Charlie Lofgren, W6JJZ, who is the world's leading authority
on Z-Match tuners. I asked Charlie to design a simple tuner that would work on 40 meters
for a talk that I was going to give in Ft. Smith, Arkansas at Arkiecon, and he came
through with the BLT. When it was tested with a 44 ft. doublet, we found that it worked on
40 through 10 meters, not just 40!! What a deal. I designed the case, which comes with the
kit, and the case is one of the reasons that I picked this kit to be part of this series.
You will learn how to build good, solid cases out of PC board material. The parts come
precut, all that you have to do is assemble them. Plus, the kit is not built on a board,
it uses Manhattan style construction, which uses small pads glued to the circuit board as
tie points for the components and the board itself for the ground plane. You just follow
the schematic and build as you go. Very easy to do, and it frees you from having to build
only projects that have a board. The kit goes together easily in one day, and when you
finish, you have a QRP tuner that will handle up to 10 watts. The name BLT stands for
balanced line tuner. This was designed to be fed with twin lead, ladder line, tv lead, any
balanced line. But you can have a long wire and coax tuner too just by doing a simple mod.
Put another BNC connector on the back of the tuner. Place a wire from the center conductor
of the new BNC to one of the binding posts on the back (on the inside of the tuner of
course). Then mount a SPDT switch with one side going to ground, and the other to the
other binding post. Now, when you want to use the coax tuner or a long wire, simply throw
the switch and ground the binding posts. Throw the switch back to use as a balanced line
tuner Plus, the tuner comes with a built in dummy load/SWR Indicator designed by Dan Tayloe,
N7VE. The Indicator uses an LED that will go out when the best match is made and SWR is
lowest. Pretty neat idea, and it works great. Also, the kit comes with a very nice Lexan
cover which were made by Dennis Foster, KK5PY. They really set off the tuner, and I love
the "look" it gives it. You will like to show it off to your friends, and you
won't need to take off the top to show it to them. Neat idea, thanks to Dennis for coming
up with it, and making all of those covers. The two projects in part 4 will give you some more building experience, and teach you
how to mount connectors, solder wires, do point to point building, and gives you a start
on a great, tool, the Manhattan method of building. Hope you enjoy the series, and I
encourage you to keep building and learning. Part 5 will be our first serious rig. It is a
single band transceiver, and it comes with VFO and is a classic kit. You will enjoy it. 72, Doug, KI6DS
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