wrote in message

Direct conversion (DC) won't be effective on this
application for reasons of the civil aviation band
being AM with no pilot carrier or other reference.

SNIP - [lots of good information]

VOR (Very high frequency Omnidirectional radio Range)
was designed only for aircraft obtaining bearing
information to a fixed ground station. That's a
limited application although extremely important to
pilots. A half century ago it was a quantum leap
above older raw-DF-style radionavigation. GPS it
ain't, nor never was...



Well, that was certainly a very informative and well thought
out response! But GEEZ, Len, you're starting to take all the
fun out of this by insisting on injecting reality!!!....8-)

Here I was - with soldering iron warmed up and pile of odd
looking components (SA-614, MC1350, NE567, inductors,
IF transformers and all kinds of other "stuff" that's unfamiliar)
and now my hopes are dashed............

I even checked Mouser, Digikey et. al. - and they're fresh out
of goniometers - so there goes *that* approach...8-(

But seriously - let's look at the potential utility of a fairly "mindless"
NAV receiver as it might apply to the non-instrumented-rated,
day-VFR "Sport" or "Recreational" pilot. First off, these guys
believe that GPS coupled to a simple moving map display represents
not only the holy grail - but they'd be willing (foolishly) to bet their
lives on this sole-source nav capability (never mind simple "dead
reckoning" or other elementary - e.g. "follow roads" forms of
navigation). If the batteries run out on the GPS - or the guys at
Cheyenne Mountain pull the big red lever marked "scramble GPS"
for whatever reason - they're in big trouble. Standard VOR-based
equipment would give them a way out - but they don't have it ('cause
it costs too much) and they wouldn't know how to effectively use it
anyway ('cause they aren't instrument rated). Some form of relatively
simple (albeit far from accurate) NAV capability would at least give
them a last chance to drag out the sectional and try to determine roughly
where they are - hopefully close enough to find a place to put down.

My ridiculous little experimental project is to try and come up with a
"poor man's" (and perhaps "stupid man's 8-) nav capability based on
VORs which is inexpensive and SIMPLE. There's no OBS nor any
other "normal" features (e.g. ability to drive a CDI) - but it kicks out
enough info relative to a few nearby VORs so that you can at least
determine what planet you're on 8-).... and provide a few hints as to
*where* you are on that planet...

GPS replacement? Absolutely not. TSO'd NAV receiver replacement?
Nope - not that either. Inexpensive (enough so that you might actually
install one) and simple (enough so that you could derive some useful info
with little training) - that would be the goal.

In the meantime, it's really a personal educational and entertainment
toy to play with, and nothing more ("amateur", "homebrew", etc. - so
it's relevent here, right?)......8-)

I appreciate your thoughts and comments, Len! You obviously have a
wealth of experience to draw upon and I thank you for sharing it. Despite
more than 25 years in product development, most of this is new territory
for me (and I'm enjoying the learning experience!). I've never done an
RF design - well - at least not "deliberately"!!!

Regards,
Bill