2 o'clock in the morning, far away AM signal

Mike Dennis · From: Stevens Point WI.

It's generally a country song drifting in and out of the air waves from some far off location... and it's the steel guitar that sticks out in the mix through all the static.

Curt Olsen · From: St. Paul,Mn USA

I come upon stations like that now and then going home from the playing job. If I do, it never fails that when the steel ride starts, it fades out or I go under a bridge and loose
the signal.

Marty Pollard · Posted 19 Feb 2000 8:20 am

I used to drive a '64 Chevy stepside PU to and from all the gigs. It had a tube AM radio and, man, that thing pulled in signals from Monterey to Toronto and from Denver to Tallahassee at three in the morning. Too cool!

Mike Dennis · From: Stevens Point WI.

I spent many a weekend night driving back from a gig that was two to three hours from home.

Nothing like being out on the open road in the early morn and picking up those far off stations... fadin' in and out....

and the occasional Northern Lights display was an added bonus too...
and if the gig was far enough away... the early dawn.

C Dixon · From: Duluth, GA USA

Marty,

I love ya man, but gotta jump in on this one. The ability to receive far and long distance AM stations at night is not a funcion of what kind of radio.

It has to do with a phenomenon that occurs when the sun no longer heats up the ionosphere which of course is at night.

AM waves being longer than FM waves will bounce off the ionosphere layer when the sun is not hitting it.

So, if when these AM waves bounce off, and your area is right under the reflected wave, it is no different than if you were in the same city as where it is transmitted. As a matter of fact it can even be stronger because it is coming straight at you from above and not obstructed by terrain and/or bldgs.

The reason it fades is caused by the fact that the Ionosphere is not consistently thick. It has holes in it. Since the earth is revolving with respect to it, If you get under one of these holes the radio waves will go right thru it and it will not reflect down to you. In just a few moments when the earth has revolved just a bit more the ionosphere again is thick, you will again get the signal loud and clear.

Go with God,

carl

BDBassett · From: Rimrock AZ

Long long ago, I was married to a DiscJockette who hosted the all night show on KMPS AM in Seattle. She received a letter one day from a fellow in Austrailia, an amature radio buff, who had been able to pick up the show more than half way 'round the world because of the phenomina of Ionic Skip. Pretty cool eh?
He described what kind on antenna he was using and all sorts of other technical stuff.
The station engineer just ate it up. BTW, she's on the air in Las Vegas these days. Maybe Tony Davis can listen in to Susan Falconer.

Rich Paton · From: Santa Maria, CA.,

"it's the steel guitar that sticks out in the
mix through all the static."

Mike, about five years ago I was eating dinner at a Chinese restaurant, and had background muzak at a very low level.
I could tell it had a PSG player imitating twangy oriental instrument they play their melodies on.
At one point something about a song kept really bugging the heck out of me, and then I realized that the melody was "Autumn Leaves", a tune I had just worked up with a Steel player (I'm a lowly 6-stringer)not more than two weeks earlier.
That PSG cut right through the muddy mix.

I still picture the guy playing that kind of music, wearing a cowboy hat! :>)

BTW, don't you just hate it when you catch a tune on the radio, really dig it, and the title & artist aren't mentioned? :>(

Is it just me, or does it seem that the quality of reception is always inversely proportional to the style of music you want to hear (or can stand)?

Marty Pollard · Posted 19 Feb 2000 10:58 pm

I had a loose grasp of the behavior of amplitude modulated signals but your information helped me to understand it better, thank you. What about the phenomenon of tube radios seeming to capture the AM signal better than the new solid state radios (ok, they're not all that new)? Is that just my imagination or is there something to that?

Mike Dennis · From: Stevens Point WI.

You can't beat the sound of those old tube radios

Rich... just last Friday afternoon I heard a great song by a female vocalist that really caught my attention... the song sounded like it was by the early 70's Fleetwood Mac...it had that sound but this was definitely country...

I cranked up the radio to catch the name of the artist..

all I got was..

WDUX AM 800 Classic Country..

now I'll most likely never know who it was.

I'm still waiting to hear a song that I once heard back in 1974, and never heard again.

C Dixon · From: Duluth, GA USA

Marty, in the early days of AM radio manufacturing, they often used an RF (radio frequency) amplifier as the first stage after the antenna's input. Automobile radio's did this a lot.

When one has one of these radios, you will pick up stations impossible to receive when they do not have that RF amplifer.

However, there would be NO difference in a tube's vs a transistor's ability to capture. If, both had the subject RF stage of amplification.

With the advent of FM and TV, most manufacturers dropped the idea of an RF stage, because it's pupose was rarely used by the masses. Hope this helps in understanding a little better, the mysterious world of "radio probagation".

Go with our Lord,

carl

Mike Dennis · From: Stevens Point WI.

One thing I don't like about the new digital tuners for car radios...

there are times when an AM signal comes in muted... with the old knob style tuner... you could tune in just off center of the frequency to add clarity and treble... This is especially important when trying to tune in late night stations.

On some radios today... you can't do that anymore... the tuner automatically searches for the next station.

Buddy Carter · From: Spring Grove (Chicago), IL

C Dixon:
I was wondering, would a better antenae take the place of the RF amp? Seems, either way, gain is gain, so if the antenae is better it should be like another gain stage. Am I close in my thinking?
bOb:
sorry; didn't mean to make this an electronic
tech thread in the wrong section.

Tim Rowley · From: Pinconning, MI, USA

Gotta add my $.02 here. Ever since I was a young kid, I've always been a listener to late-night AM skip, unlike nearly everyone else I know. Back in the days of all-tube radios with big speakers and RF stages, we got to town about once a week for church on Sundays and that was about it. But on one of those rare Friday evenings when we went to town (stores in the little farm communities used to stay open until 9:00 PM on Friday nights in the summertime) I walked over to the Gambles store and spent some of my hard-earned produce-stand money for 50 feet of 14 gauge wire. I subsequently installed a longwire antenna in the upstairs of our big old farmhouse which could be connected to the external antenna clip on "the radio". Boy would that thing ever bring in those 50,000 watt clear channels at night. I mean most all of 'em! I still have access to my mother's old pre-war tabletop Setchel-Carlson which plays good and maybe someday I'll hook that up to a longwire (or a wire fence) and listen to WBAP, WWL, some of those stations whose call letters start with "K", and some of the great Canadian stations as well. To me, nothing else sounds like a classic country or western swing tune coming out of the speaker of an old tube radio--and yes, the steel guitar always cuts thru the mix! Thanks Mike, Carl, and everyone else for this thread.

C Dixon · From: Duluth, GA USA

Buddy Carter,

Very interesting question.

Best answered this way. NO amplifier can amplify something that is not there. So what you are saying is true to this extent;

If one can devise or install an antenna that can capture more signal than another device, then yes that is very important in getting more signal.

Having said that though, in most practical applications, a better antenna is NO match for an RF amplifier if there is any signal at all with the "lessor" antenna.

Here is an example: A 3 to 10 DB gain which is about the best one can hope for in a given antenna over another antenna is about it.

An RF amplifier can have typically as much as 20 to 30 DB gain (or more!). Now remember in terms of voltage only, (we are not talking about power) each 6 Db gain or loss multiplies or divides by 2 (into 75 ohms).

So a better antenna helps yes, but nothing takes the place of an RF amplifier and a decent antenna.

There is another very, very important thing in what the final result is at the speaker of any electronic receiving device. And that is noise. Many people including some missinformed technicians believe that the noise one hears in the background of weak signal stations comes from the air. NOT so! (lighting excepted).

It comes from the converter stage, which is the FIRST stage on a tuner be it AM, FM or SSB, if it does not have an RF amplifier stage.

A good example of this is on a TV. Tune to a chanel that has nothing on it and look at the "snow" (noise)on the screen. Over 99% of this noise comes from the converter stage of the TV's tuner. That is why on a TV, an RF stage is absolutely critical. Because a human's eyes are many times more sensitive than our ears.

Now back to AM. With no RF stage, weak stations are particularly hampered because the noise generated by the converter stage takes precedent. Increasing the volume does increase the music BUT the noise ALSO increases.

IF one can install an RF amplifier ahead of the converter, it will increase drastically the signal to noise ratio and now even weak staions can sound very clear even at louder volumes.

As such, all "ham radios" have at least 1 stage of RF amplification and some have 2 or even 3!

Take care and God Bless you always,

carl

Gaylon Mathews · From: Jasper, Georgia

Can a person by an after market RF stage for an AM radio these days?

------------------
Gaylon's Homepage
www.geocities.com/nashville/1064

C Dixon · From: Duluth, GA USA

Gaylon,

I doubt it. I have never seen one. It would be great for listening to "clear channel" stations at night. IF they still have clear channel stations. I am not sure that is still the case.

For those of you that don't know what is meant by "clear Channel", back in the early days of radio transmission our federal government set up a system whereby some stations in the US could operate on a designated frequency that NO other radio station in the US could use.

WSM in Nashville was one of these. I don't recall how many statons were allowed this, but it was not many. That is why WSM has always been listened to by soo many. One other thing the FCC did was to make all stations, except these "CC" stations reduce their power about the time the sun goes down in that station's area. Then resume to full power about the time the sun comes up the next morning. If they did not do this, listening to AM at night would be one garbled mess indeed.

A thought my preciuos friend Gaylon: if you want to listen to WSM at night, do this: Go to junk yards and pawn shops and try and find an old automobile radio that is still working. See if you can take it back if it does not have an RF stage. Then take it to a reputable radio/TV repairman to ascertain that it does in fact have an RF stage.

Then buy a 12 volt DC power supply from radio shack. Ask that repairmen to show you how to hook it up so the radio will work. Hook up a spkr to it.

Then buy an old fasshioned car radio antenna and plug it into the antenna jack on the car radio.

For even clearer reception. Get about 80 -100 feet of braided copper wire and hang it between trees if you have them near your house. and attach it to the antenna you bought.

WARNING: if you do this. Diconnect that thing if there is EVER even a hint of lightning near your home. So I strongly suggest a "disconnect" of some sort on the outside.

I believe Radio shack sells a kit that includes an AM radio antenna kit. But increase its length if it is not at least 80 feet long.

It is permissable and in some cases desirable to have one 90 degree bend in the wire. and a lead or drop wire into your house is also ok.

Love ya man,

carl

Tom Olson · From: Spokane, WA

I guess this phenomenon of "ionic skip" is why all the trucker's radio shows are on the AM channels and are on late at night. When I was a kid in Minnesota in the early 70's, I used to listen to the Charlie Douglas Road Gang show out of New Orleans just about every night -- I think it was WWL.

Steve B · From: Garland Texas

Tuning in AM radio in the middle of the night is a great way to find some old country music, or some good talk radio, and also is a great way to irritate every one else in the van. My problem is, that when our drummer takes his turn behind the wheel, I get to hear his really bad sound quality tapes of Neil Young.

Mike Dennis · From: Stevens Point WI.

Our drummer use to cruise with me in the equipment van... he was a real hyper dude...

always on the way home he would have to buy a mountain dew and big bag of doritos... then he'd eat the who bag ( ranch salt ) and guzzle the dew... turn my radio to some heavy metal station and crank it... and the speaker was on the drivers side..

I'd wear my ear plugs....

Generally he would pass out after awhile... and then I could tune in my favorite late night music... old country.