The Electrical Contractor Network

ECN Electrical Forum
Discussion Forums for Electricians, Inspectors and Related Professionals

Books, Tools and Test Equipment for Electrical and Construction Trades

Register Now!

Register Now!

We want your input!

Featured:
   

2017 NEC and Related
2017 NEC
Now Available!

   
Recent Posts
Sprinklered equipment 26-008
by bigpapa
Yesterday at 04:24 PM
On Delay Relay with Auto Reset
by Potseal
12/01/16 09:59 AM
Wow, that was close!
by jraef
11/28/16 07:06 PM
Earthquake in New Zeeland
by RODALCO
11/27/16 11:25 PM
Calling all Non-US members!! (Non-US only)
by Tjia1981
11/27/16 06:33 AM
New in the Gallery:
12.5A through 0.75mm˛ flex (just out of curiosity)
Shout Box

Top Posters (30 Days)
gfretwell 15
HotLine1 10
Trumpy 8
Texas_Ranger 8
sparkyinak 7
Who's Online
1 registered (gfretwell), 218 Guests and 4 Spiders online.
Key: Admin, Global Mod, Mod
Page 1 of 3 1 2 3 >
Topic Options
Rate This Topic
#21247 - 01/29/03 08:56 PM AM Radio?
Trumpy Offline

Member

Registered: 07/05/02
Posts: 8540
Loc: SI,New Zealand
How much is AM radio used in the US these days?.
Has it lost it's appeal to FM radio?, just being a poor cousin, because of static and other Electro-magnetic Interference?.
Please put your 2 cents worth in-
_________________________
Let's face it, these days if you're not young, you're old - Red Green grin

Top
Work Gear for Electricians and the Trades

Work Gear for Electricians and the Trades
Work Gear for Electricians and the Trades
Arc Flash Clothing, Gloves, KneePads, Tool Belts, Pouches, Tool Carriers, etc. etc....

#21248 - 01/29/03 09:01 PM Re: AM Radio?
Wirenuttt Offline
Member

Registered: 11/10/02
Posts: 267
Loc: Massachusetts
FMs for music, AMs for talk, politics, weather and traffic reports.

Top
#21249 - 01/29/03 09:08 PM Re: AM Radio?
Bill Addiss Offline
Member

Registered: 10/07/00
Posts: 4196
Loc: NY, USA
Trumpy,

AM still has it's following. I think mostly among the 40+ crowd. My dad didn't even realize that his car radio did not get FM for years.

Bill

Top
#21250 - 01/29/03 10:07 PM Re: AM Radio?
Bjarney Offline
Moderator

Registered: 04/10/02
Posts: 2561
Loc: West-Southern Inner-Northeast ...
MP3 {internet} broadcasting and recording are becoming serious competitors to conventional radio.

And now there's the XM satellite stuff, too.

Top
#21251 - 01/30/03 05:20 AM Re: AM Radio?
SvenNYC Offline
Member

Registered: 08/19/02
Posts: 1685
Loc: New York City
The bulk of listening is on FM -- about 80 percent of the listening audience listens to FM. The remaining 20 percent listen to AM.

If you look at the ratings for most American cities, you'll find one AM - usually a high powered one near the top of the general 12-plus ratings - with a non-music type format (news/talk/sports).

AM is more and more turning into the home of specialty programming: "foreign" language stations (Chinese, Korean, Spanish), leased access (pay for your air slot) and religion.

Top
#21252 - 01/30/03 04:48 PM Re: AM Radio?
ThinkGood Offline
Member

Registered: 08/07/02
Posts: 1084
Loc: Milwaukee, WI
Gosh, I remember when KYW (note the K callsign) in Philadelphia, PA went to AM Stereo.

I never did understand what all the hype was about. They are an all-news station

There is plenty of AM in use here in Northern NJ. Until I put Cat-5 in at home, the RF interference was louder than the other party asking "Do you have the radio on?"

Have a look at the US stations via: http://svartifoss2.fcc.gov/reports/state_rs.cfm

Top
#21253 - 01/30/03 06:47 PM Re: AM Radio?
SvenNYC Offline
Member

Registered: 08/19/02
Posts: 1685
Loc: New York City
Thinkgood:

That's cuz all the NYC AM stations have their transmitters in your back yard!!

Serioursly...for example if you take a trip out to Giants Stadium you will see the three towers that make up WEVD-1050 AM's array.

Since it's marshy water and open ground, it's perfect for AM.

The AM station's tower you seeis only half of the antenna. The other half is underground and consists of long copper radials, buried into the bog.

Thieves have been known to dig them up and sell the copper. This happened some decades ago to WCBS/WFAN's tower out on High Island, off the coast of The Bronx (here in New York).

Top
#21254 - 01/30/03 07:21 PM Re: AM Radio?
ga.sparky56 Offline
Member

Registered: 11/24/02
Posts: 582
Loc: young harris georgia usa
I remember WLS in Chicago was a very powerful am station in the late 60's and early 70's, 89 on the dial I think.Anybody else ever listen to rock and roll from there?

Top
#21255 - 01/30/03 09:11 PM Re: AM Radio?
Scott35 Offline

Broom Pusher and
Member

Registered: 10/19/00
Posts: 2724
Loc: Anaheim, CA. USA
Oh ya, Awful... I mean Amplitude Modulation is still a widely used format here in So. California.

Not so much music, but many talk stations!

One certain station - with the pilot frequency of 640 kHz, will always be around (it is an alternate for some type of tracking signal, or something like that!).
It is also the station heard on POTS lines when something is screwed up - like poor connections or water damage.

Read awhile back about experimental Digital AM stuff, which would give similar results found on VHF FM broadcasts.

The typical VHF FM channel is 200 kHz wide, and normally includes Stereophonic info (also Quad!).
The HF AM channel is 10 kHz wide, so to get something nice for music inside this envelope, it would need to be compressed someway.
Also sending Digital Packets would reduce the Atmospheric noise that gets included when the audio info gets extracted from the carrier, and sent to the power amp.
(the crackles that are heard).

Scott35 S.E.T.
_________________________
Scott " 35 " Thompson
Just Say NO To Green Eggs And Ham!

Top
#21256 - 01/31/03 06:05 AM Re: AM Radio?
pauluk Offline
Member

Registered: 08/11/01
Posts: 7693
Loc: Norfolk, England
AM was still going strong in rural Nebraska when I left there in '96. A lot of talk/news stations, parts of the public radio network with some quite interesting shows from time to time.

There were also plenty of oldies and country AM stations when I was in the South a couple of years before. (Completely unjust in my view that so many stations playing decent music go on AM while the FM band is full of the "Top 40" trash!)

Trumpy,
ThinkGood mentioned KYW in Philadelphia. Just in case you're not aware of this, in general U.S. stations have W callsigns east of the Mississippi River and K callsigns west of it. There are exceptions though, such as the old-time KDKA.

Another AM broadcast difference is that in the Americas stations are on a 10kHz channel spacing, whereas elsewhere in the world we are on 9kHz (e.g. 1152, 1161, 1170 etc.)

Scott,
In the U.K. AM broadcasts have always been constrained to a 4.5kHz audio bandwidth by the 9kHz channel spacing, but I seem to recall reading a few years ago that the FCC authorized some U.S. AM stations to broadcast a wider bandwidth signal, presumably only where it was deemed that the wider sidebands would not interfere with adjacent channels.

It struck me as rather odd at the time, as it would be of no benefit unless AM receivers were also designed for the wider bandwidth, in which case they'd be wide open to adjacent channel interference when tuned to weaker "normal" stations.

I have a feeling that the piece I read was in error, but can you confirm this?


[This message has been edited by pauluk (edited 01-31-2003).]

Top
Page 1 of 3 1 2 3 >



ECN Electrical Forums - sponsored by Electrical Contractor Network - Electrical and Code Related Discussion for Electrical Contractors, Electricians, Inspectors, Instructors, Engineers and other related Professionals