"Jim, N2VX" ) writes:
On Fri, 19 Dec 2003 22:11:23 -0000, "Richard"
wrote:

Hi. Anybody developed a nbfm RX project covering the FM band (appx
87.5Mhz-108Mhx).

With digital readout, though I suppose I could just hook up a simple a
frequency counter to read frequency.

TIA. Rich.


If you want to do DX'ing get an existing receiver and put in a
narrower filter. Many of the older tuners are ideal for this. I saw
writeups on this in magazines over 20 years ago and don't remember
what bandwidth filter was recommended.

An interesting project would be mods to the GE SuperRadio II or III.
They are cheap, available and have a tuned RF stage.

73,
Jim

That's a bit misleading. Most FM BCB receivers, now and in the past,
have an RF stage ahead of the mixer, and it is tuned. I once had
a nice Sony stereo receiver that worked well on FM, and it's lack of
an amplifer ahead of the mixer was pretty uncommon (and likely accounted
for it's good overload resistance).

The "TRF" stage in a Superradio is in reference to the AM band,
where in non-car radios, an RF stage is an exception.

Also, while it does seem a bit of work has been done in the design
for better AM reception, that RF stage and the better than average
loopstick, it does not seem like the FM section is anything to write
home about. I gather it's a fairly generic design.

This is part of the mythology of the Superradio. It's not all that
great, just maybe a little bit better than the average portable or
table radio, but people point to it when the concept of "a better
radio" comes up. Once you start spending the money, better to spend it
on a better design. Or better, buy a car radio that will have good
reception, or some used stereo that did have a bit of extra care in it's
design, so it actually won't overload in an urban environment.

Michael VE2BVW