[HomeBrew] Any builders?

[Chris Trask]

>
> >
> >Isn't anyone homebrewing anymore? I see no posts here.
> >
> >Loren  WA7SKT
> >
>
> ***
> I know!
>
> There's not much a person can do any more. At least me.
> #1, It's all been done before
>

    Not necessarily true.  A good number of designs that I see, both
solid-state and tube, tend to be a bit too complicated to gain the interest
of entry-level homebrewers.  There is a bit too much emphasis on multi-band
and/or multi-function receivers and transmitters.  The older handbooks had
plenty of simple one-band rigs that used parts that were readily available
at the time.  The challenge now is to build similar equipment using parts
that are presently available.

    Just because a rig is "simple" does not mean that it has to have less
than adequate performance.  In the days of yore, AM transmitters relied
heavily on plate modulation of the final stage, and mostly this was due to
the lack of suitable linear amplifiers.  Simple feedback techniques exist
now that will allow builders to make small, low-power AM and SSB
transmitters (aka exciters) with good performance that can be later followed
by power amplifiers that achieve cleaner, more efficient operation without
resorting to elaborate parts or techniques.

    However, many articles I see place a lot of unnecessary emphasis on lots
of whiz-bangy microprocessor controlled synthesizers and DDS signal
generators.  That's not to say that advancing the state of the art should be
shunned, but rather entry-level projects, or even weekend "fun" projects
should be kept simple, using parts that are readily available from mainline
sources such as Digi-Key and Mouser.

>
> b) they have an ability to program computers or PIC chips, or
> c) have $$ to invest in PIC programmers, PC board making, printed circuit
> board runs of 100+, and etc., etc., etc.
>

    Which is part of the point I'm trying to make.  Very worthwhile projects
can be devised that do not require this stuff.  Even solid-state projects
using discrete transistors and point-to-point wiring can have very usable
performance.

    Projects that showed up in hobby magazines such as Popular Electronics
in the 60's were generally very simple.  True, they migrated to items that
had PC boards available, but they still had plenty to offer that could be
made on vector board.  I recently saw a web page where a fellow had come up
with a wonderful multi-band solid-state receiver that was built entirely on
vector board with buss wire for the long conductor runs.  Nothing wrong with
that at all.

>
> Our hobby has changed a great deal since radio glowed in the dark. Since I
> was winding transformers from scratch and using a Greenlee chassis punch
> to mount the tube sockets for 6x4's, 12AU7's, 1625's, and 304TL's.
>

    Lucky you.  When I was in high school, my shop tools for tubes consisted
of a hand drill, a set of files, and an Adel nibbling tool.  I would glue a
sheet of paper on the chassis, draw my large holes with draughting
templates, then drill a series of 1/4" holes and finish it off with the
nibbler and the files.  It wasn't until I became interested in designing
with tubes in the past ten years that I ever owned a Greenlee punch.

Chris

     ,----------------------.       High Performance Mixers and
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   \  _______,--------------'           Chris Trask / N7ZWY
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