On Mar 16, 11:26�pm, "gbowne1" wrote:
Hello! :-)

* I'm interested in homebrewing. *I've been a SWL since 1986, and I'm
a newcomer to amateur radio, although I have been interested in that
since then too, and will be getting my ticket during the course of the
following year.

Excellent!

*I now own a Yaesu FT-757GX which I use as my HF Gen
coverage receiver so I can still listen to SW, and practice code and
then get my ticket, while working on building the rig and slowly
learning still. *Mind you, I also have a Fluke 8050A DMM too that I
bought last year which will help me. (Still learning how to use it)

A good start.

* In an effort to help me learn more about electronics than I already
know, not a whole lot at this point, I am going to build something
with which I can use once I finally get my ticket.

* In search for helpful documentation, I found a book by Randy L.
Henderson, titled
"Build Your Own Intelligent Amateur Radio Transceiver". *While now 10
years old, the book has many outdated components, and other errors in
the book. *While a good design idea, I think it could be improved on
to 2006/2007 standards in many ways.. which I will attempt to do. *The
rig is based on the 80C31 / 8051 family with a 27C64 EPROM in with a
7805 regulator, and 74LS373 on the computer board. *The computer board
also listed as having: a 1N4001, a 1N4148, a 2N2222A, a 2N2907, and
lastly a SK3444. *It also featured a 100,000uF memory backup capacitor
and a 6.2v Zener.

* My basic dimensions for the chassis are 16.1875" W x 6.1875" H x 15"
D.. so that will be the working envelope of whatever design I end up
with. *That's a pretty big space, and I like having space to work
inside.

IMHO:

From what I gather, you don't have much experience with
practical electronics. If I'm wrong about that, please
correct me. Nothing wrong with inexperience, everyone
starts out that way.

The main problem I see with something like the "Intelligent
Transceiver" is that it is a very big thing to do as a first or
even second project. Not that it can't be done, just that I
cannot recommend it as the way to get started. It's just
too big and complex for a beginner.

I recommend that you look around for a simple receiver
or transceiver project to build. There are many designs
on the web, and kits too. Most are single-band projects
built around a handful of parts, yet capable of usable
performance with a decent antenna. You can learn a lot
from building one and getting it to work, and then move on
to something more complex. In some cases ready-made
PC boards are available, but you have to provide the parts
and enclosure.

You will need some tools, test equipment, and a proper
place to work. One of the advantages of kits is that the
required tool kit is greatly reduced, but so is the amount
of creativity and craft you put into the project.

Look around the internet and your Handbook for a simple receiver or
transceiver project to build for a start. It doesn't
have to use the latest technology in order to work and teach
you many things about radio. Note too that many transceiver projects
can be built as receivers by simply leaving the transmit components
out until later.

Another poster here advised you to build a simple regenerative
receiver. This is excellent advice, because
a regen is about the simplest practical SW receiver you
can build that will give useful results. It will also teach you
a lot about construction technique and operating skill. It
will also make you appreciate a superhet!

The advice to study an "All American Five" receiver, OTOH,
is very bad, for a number of reasons:

1) You want to build, not take apart. In theory you could take an AA5
all apart and put it back together again, but
that's not the same as building something new.

2) There is a good chance that if you can find an AA5, it
will need to be fixed to make it work. While you can learn
a lot that way, it's still not the same as building something new.

3) The end result of any such effort is going to be a basic receiver
for AM broadcast. Not a transmitter or transceiver, and not a piece of
amateur radio or SW equipment. If amateur radio/SW is your interest,
it seems to me that your projects should be for amateur radio and SW,
not AM BC.

4) AA5 receivers are of transformerless, "AC-DC" design. Usually one
side of the AC line is directly connected to the chassis. If the plug
is put in the socket one way, the chassis is connected to the neutral
wire, but if it's plugged in the other way the chassis is hot-to-
ground by the line voltage! Such receivers were almost always built in
cabinets of insulating materials such as wood or plastic, and the
chassis made inaccessible, because of the shock hazard. But in order
to work on one, you want it out of the cabinet and powered up.

Working on one requires a lot of extra precautions to avoid getting a
shock. Better to focus on transformer-operated equipment whose
chassis can be directly grounded to minimize the shock hazard.

---

Tubes or transistors? They're both fun, and both have
advantages and disadvantages. Solid state parts are generally more
available new or new-old-stock (NOS), though.

Google my callsign to see some of my homebrew efforts.

And keep asking questions!

73 de Jim, N2EY