Regarding “Little Joe”
Wes Hayward, September 9, 2015
An article by Doug DeMaw, W1FB, (SK) in the September 1981
issue of QST featured a simple CW transmitter. The
article was titled “Experimenting for the Beginner” and
talked about some of the things that one might do if he or she had
never built a circuit of any kind. The transmitter
was a variation of one that Doug and I had included in our 1977
book, Solid State Design for the Radio Amateur.
We named the little rig from SSD (p26) a “Universal QRP
Transmitter.” Nowhere in the QST article text, the related
figure captions, or even the references does the term “Little Joe”
appear. Yet this is the popular name that has been
attached to that design. I finally discovered the
reason. The circuit board photo (p45 of the QST, above
figure) reveals the “Little Joe” name, etched into the foil.
This design is very old and suffers from numerous
problems. Yet I continue to receive questions
about it. Folks continue to build it.
Pre-etched circuit boards are rumored to still be available from a
bargain basement source that does not bother to include any road
maps (layout diagrams showing parts placement) with any of the
boards that they sell. Many current builders are using the
on-line copy of the QST article that is available (members only) at
the ARRL web site, but the figure resolution from that copy is
poor. I got permission from the League to put slightly
higher resolution diagrams on my website.
The “road map” and a board photo are shown below. These
were scanned from the original paper QST.
I do NOT recommend this design which is, by now, well over a third
of a century old. Rather, a design that meets FCC
specifications and has numerous operating features was presented in
a recent QST. See “An Updated Universal QRP
Transmitter,” QST, April 2006, pp28-32. A
related note appeared in Technical Correspondence, QST, July 2006,
pp65-66. Errata for the article appear on this web
page at http://w7zoi.net/mark2.html
which includes comments about up to date, available, cheap
transistor types. The updated design appeared in
some recent issues of the ARRL Handbook. The new
design does not have a printed board layout.