From: John De Armond
Newsgroups: rec.outdoors.rv-travel
Subject: Re: Traveling  and AM Radio.
Date: Mon, 16 Jul 2001 22:59:19 -0400

ben hogland wrote:
>
> A friend at work got one a few weeks ago for use at his new Cabin in Glacier
> near Mt. Baker. He initially borrowed mine for a weekend just to make sure
> it worked for his situation. Like you, he wanted it for Baseball Games.. He
> was very happy with how it worked so decided to buy one. Better yet, he was
> able to get one on eBay for 31 bucks.  Shop around, you can find them
> cheaper then what C.Cran is asking. The best thing would be to borrow one
> for a weekend to see if it works as you expect it should. C.Cran does have
> an excellent return policy but you'll pay the price for buying from them.

I get that slimy, nasty feeling every time I see C.Crane mentioned,
probably because of his close association with that nutcase, Art
Bell.

Anyway, the cheap and more effective way to extend AM radio range is
to string some wire outside the RV (from one end to the other, for
example), bring the wire inside, wrap several (5-10-15 turns -
experiment) turns of wire around the ferrite antenna stick of the AM
radio, then connect the other end of the wire through a "BC" tuning
variable capacitor (radio shack) to the RV chassis.  Set the radio
on the station and then tune the capacitor for best reception.
Total cost is < $5.

Cheap and effective method #2.  Get a good AM/FM car radio from the
junk yard (I've had good experience using the one from a Geo
Metro).  Pay no more than $30, preferably no more than $20.  Mount
it in the RV, making sure it is well grounded to the RV frame.
Install an external car antenna on the outside of the RV.  Connect
it to the radio.  Find the AM radio "peaking" adjustment on the
radio - usually a recessed screw near the antenna connector.  Tune
your favorite station and then adjust the peaking adjustment for the
best signal.  This adjustment is a small capacitor that does the
same thing as the "BC" cap above.  Optionally for even better signal
strength, string some wire from the antenna, keeping it insulated
from ground.  Re-tune the radio using the peaking adjustment.
reorient the wire for best reception.  Generally, the longer the
wire the better.

In my limited experience, I find that the cheaper non-stereo car
radios tend to have the best AM receivers for some reason.  I'd love
to find a comparison of AM radio sensitivity and selectivity
somewhere.  Lots of magazines, etc, review the FM and stereo
sections but none seem to pay any attention to AM.

From: John De Armond
Newsgroups: rec.outdoors.rv-travel
Subject: Re: Traveling  and AM Radio.
Date: Tue, 17 Jul 2001 01:08:51 -0400

JPSJPS wrote:

> John - Sensitivity at AM frequencies is not critical since the
> atmospheric noise picked up by the antenna is much higher than the noise
> generated by any decent receiver front end.  You can verify this by
> disconnecting the antenna and the receiver output noise drops.

Well, that's the simplistic textbook answer.  In the real world, the
receiver quality matters.  A lot.  I fought the battle for a long
time to receive WSB 750 AM from Atlanta here.  Same antenna, same
power supply, same speakers.  Trying a wide variety of auto radios
from the junkyard, I found the Geo metro to perform the best.  By a
large margin.

> How many people listen to AM any more?

Lots.

> Probably not many except those in
> the boonies where no FM is available.

Talk radio (rush, etc) has done wonders to resurrect AM.  As of the
last time I cared enough to keep track (coinciding with the last
time I bought radio spots), talk radio is the fastest growing
segment on radio.  AM is tracking right along.

> Probably not a big concern for > today's radio manufacturers.

Probably true.  Which is probably why the original radio (with every
RF stage permeability tuned) in my 68 Fury receives AM better than
any modern radio I've ever tested.

John

From: John De Armond
Newsgroups: rec.outdoors.rv-travel
Subject: Re: OT: (sorta)  AM DXing
Date: Tue, 14 Aug 2001 01:48:31 -0400

ben hogland wrote:
>
> "Chris Bryant" <BryantRV-02@cfl.rr.com> wrote in message
> news:pt3dntclu5h60mu8aif42psdourecqhm86@4ax.com...
>
> > One of my favorites for AM DXing is to find a Delco radio from
> > a '60's automobile- some of these had *very* good reception, and can
> > often be found for peanuts.
>
> I've heard other people remark about those old Delco Radio's too..  It seems
> they don't build them like they use to. But for an all around good portable
> AM/FM radio currently in production, the Superadio III is probably the best
> in it's price range. I guess I'm not SMS enough to get one of those early
> Delco's and mod it into a portable table radio. :-)

Some of the modern mobile radios are good too.  They have to be to
survive in the RF environment in and around a car.

I spent some time at the junque yard testing radios and found the
one from a mid-90s Geo Metro to have a quite good AM receiver.  My
quest is to be able to hear WSB-750 AM out of Atlanta all day.
Especially so now that they've eviscerated their internet presence.
This radio does a pretty good job with an outside mounted car
antenna.  My next step which should solve my problem with WSB will
be a long Beverage antenna aimed at Atlanta.

It takes almost nothing to use one of these at home.  A 12 volt
power supply (a storage battery and a trickle charger if you're
cheap, a 12 volt power supply from Rat Shack or Flying J if you're
not), a speaker or two, some 92 ohm coax and an outside antenna.  I
paid $10 for my radio, had a power supply, speaker and coax and paid
about $3 for the car antenna.

My next step is going to be to hook this thing to one of the Ramsey
Electronics FM transmitters so I can receive it all over my property
with a Walkman radio.

John