On Thu, 23 Sep 2010, Nikon D3000 wrote:

Some folks just can't leave well alone!

Another way of looking at it is that a commercial receiver makes
a good start at a semi-homebrew project.

I remember one article in QST in the late fifties where someone bought
a Knight Kit receiver and never built it as instructed. He used the
chassis and such and the variable capacitors and tuned circuits but
built up a different receiver. He saved on not having to do the chassis
work.

There were lots of receivers built that way around surplus equipment.

People rebuilt older receivers, pretty much starting from scratch,
either to put in miniature tubes or solid state the receiver. They
even admitted that at that point they might as well have started
from scratch, but the mechanical work in the receiver provided an
advantage.

I was agonizing earlier in the year about buying a Grundig 4000
when they were selling for under a hundred dollars (made more
tempting by having a gift card for the store, and at least at
one point they were tossing in a windup radio). In the end,
I decided it was too frivolous. But, I was tempted precisely
to use it as a project radio. As a portable, any portable for
that matter, there are some disadvantages, and merely putting it
in a bigger case and rearranging the controls, and adding a tuning
knob (it only has up/down switches) would make a fairly great
operational improvement. Add another switch so the IF bandwidth
switch doesn't control whether FM reception is mono or stereo.
Add a preselector for improved front end selectivity. Add an analog
s-meter. Add an RF gain control, or at least multiple levels of
attenuation in the front end. Move the BFO tuning to something
that is easier to use (it's a thumbwheel). Get a ceramic resonator
and add a CW bandwidth selectivity. Get some ceramic filters and
improve selectivity. Maybe add a synchronous detector. Once it's in a
bigger box, it's so much easier to add modifications.

I thought of it as a fun project, get a leap start on building a full
range shortwave receiver, but make it more functional and easier to use.
Even at a hundred dollars, it's almost at the range where people would
consider it throwaway, when it dipped under a hundred dollars it was
even moreso.

The problem was, I already have one, bought at the $100 level last fall,
plus a couple of better Grundigs that I bought at rummage sales for a lot
less. Out of the box those older Grundigs have more features, and if I
realistically, one of them would be a better choice for this sort of work.

So in the end, I didn't pursue the project, because as fun as it would
have been, the end product wasn't necessary to my needs.

Michael VE2BVW