Canadian AM Broadcast audio?

[WA1LGQ]

Does anyone know what the audio standards are for Canadian AM broadcast stations? Are they like the US restrictions?
Thanks........Larry

[KM1H]

Dont know but the ones I listen to such as AM 740 sure sound better.

Carl

[k4kyv]

The political windbags that dominate US AM stations could just as well be on slopbucket, for what difference audio quality would make.

[flintstone mop]

The political windbags that dominate US AM stations could just as well be on slopbucket, for what difference audio quality would make.

I don't think Don listens to AM very much
EXCEPT for 1.885 or 3.880

[Steve - K4HX]

It has nothing to do with Daylight Savings Time.

[KM1H]

I find very little politics on AM in this area, its the bible thumpers who are out of control on the BCB and SW. Next on the overkill meter is the sports talk shows.

More and more are going to music formats from 50's to 80's. One I listen to is a complete independent with their own library. I switch to Internet listening when the power drops to 3W.
http://www.1540wxex.com/

I was listening on LW the other night as conditions were excellent and tuning across French rap was a laugh! OTOH another had a few hours of 60's rock.

[kb3ouk]

Carl,
I've noticed this with AM 740's audio that it has a really unique hum to it, i can usually  hear the hum all day when conditions are good even if i can't hear any audio, and its not jst something unique to one of my receivers i can hear it on all of them. I will try to get a recording of it sometime and post. I just wondered if you noticed the same thing.
shelby

[kb3ouk]

ok didnt have my odd hum on AM 740's signal tonight but here is a comparison of canadian am to american am the first part of the recording is AM740 the second part is 1530 out of Cinncinatti i think. these were received on a Philco 53-958.

[K2PG]

As far as I know, the Canadians do not use the NRSC spectrum mask, which the FCC forced on U.S. broadcasters some 25 years ago. The NRSC mask limits the bandwidth of the audio that AM stations in this country are allowed to transmit, then requires pre-emphasis of the high end to "compensate" for using a "brick wall" filter to knock out anything above 7500 Hz. Canadian stations, on the other hand, can broadcast clean, open audio. The Canadian stations are also not limited to 125% positive peak modulation, unlike their U.S. counterparts.

What makes the American regulations downright hypocritical is that U.S. stations broadcasting IBOC (the so-called "HD Radio") can occupy a 30 kHz wide channel with their digital sidebands, multiple OFDM carriers beyond the audio passband. This causes hash interference to stations on adjacent channels. To add insult to injury, IBOC AM stations generally limit their audio frequency response to 5 kHz to prevent the analog component from interfering with the digital carriers.

KB3OUK: Was the "odd hum" a 60 cycle power line hum or did it sound more like a hiss or insect noises? The 740 kHz channel frequently receives interference from one or more U.S. IBOC stations. That noise sounds like a high-pitched hiss or like cicadas buzzing on a hot summer day. I can hear that 20 kHz on either side of KYW, 1060 kHz in Philadelphia.

[WA3VJB]

The co-channel digital overlay has been completely discontinued during daytime hours on the AM band in the Baltimore-DC area, based on my scanning through the frequencies multiple times recently.

Let's hope it is a trend nationwide. It was a marketing strategy not based on practical considerations.

[W2ZE]

Let's hope it is a trend nationwide. It was a marketing strategy not based on practical considerations.

Sorry to inform you, WCAO 600 in Baltimore is still on, and the chief for WTEM 980 (a personal friend of mine) says he has repaired his exciter and will have it back on sometime soon. Dancing on our grave might be a little premature.

[longle SWL]

I listen to Toronto 740AM almost every night and have never heard a hum. However, even though they continue to insist that nothing changes at 10PM, the signal always looses strength at that time, for what ever reason.

[KM1H]

Ive never heard a hum on Toronto either and listen on many different radios from boatanchors, consoles, to a radio on a chip.

WJIB 740 in Cambridge MA runs 250W day, 5W night and 40-109W PSRA to a 280' tower and is good copy here daytime before the band starts shifting in late afternoon. Its another independent station with their own library. I get bored real fast with the canned playlist stations.

http://www.wjib740.com/

Carl

[k4kyv]

Not much audible on the AM band here that is not canned content.  Exceptions include WSM, Nashville, CJBC and CFZM in Toronto, and KRSN in Los Alamos, NM.  Except for WSM I get the others via streaming audio; I discovered CJBC 860 over the air back in the 60s, but now they are rarely entertainment quality here any more. CFZM is masked by some other station with a K callsign.

Most of what I hear when I scan the AM band at night is talk; primarily politics, sports and an occasional bible beater (all pretty much the same thing to me), and you can usually hear the same program on 5 or 6 different frequencies when tuning across the band, indicating that the stations have essentially turned into satellite repeaters. Sometimes while driving across the country I hear a few little local stations with somewhat hokey local programming, which can be interesting and entertaining for a brief  listen while passing through. I occasionally hear music, largely country and a  few rock oldies.  Rarely anything like jazz or classical.

The FM band is not much better.  Maybe a little more music and variety, but usually from a limited play list that runs over and over and over again, so that it gets tiring to listen to after about an hour.  And of course, plenty of endless strings of commercials in between the sets of a few songs.

I used to take refuge on short wave, but most of the good SWBC stations are now gone as well.  So about the only BC radio I listen to are a few non-commercials (the local NPR outlet and a couple of independent university stations). Even those may be falling by the wayside.  Vanderbilt University is considering selling their 60 y.o. FM outlet and going 100% streaming audio (not that it is actually costing them too much to run the station; they are looking at the revenue they would gain from the sale), while a small group of politicians are currently trying their damnedest to get rid of NPR.

WJIB (ex-WCAS) is taking an interesting approach.  I wish them continued success, although not my preferred music format.

http://www.wjib740.com/2.html

Some informative (cut-and-paste) links here
http://www.wjib740.com/3.html

[flintstone mop]

ok didnt have my odd hum on AM 740's signal tonight but here is a comparison of canadian am to american am the first part of the recording is AM740 the second part is 1530 out of Cinncinatti i think. these were received on a Philco 53-958.

Ouch that hurts my ears!!
Was that a microphone recording near the speaker??? Or direct out through an interface to a computer recording the audio?? Nothing but a midrange sound no lows at all.
Carl the link to the 1540 station sounded really nice.

And W2ZE my apologies for negativity toward HD BC. It's too bad the USA has to have this 'compatible crap' that we have these sideband issues with digital vs the analog in the same spectrum BUT once my HD radio locks in on the one AMer in my market it is simply beautiful audio. And surprisingly no drop outs for the entire 30 mi ride to work............they talk about jocks no music.
The FM HD stations we have near Western Pa. DO sound like great CD audio. Extra bass the 30 hz stuff in the Katy Parry type music just rumbles through and the high end is really smooth. The stereo is fantastic!!!! Sorry to drift off the subject.
I'll try to tune in on my FLEX tonight for the "air sound" of 1540 and 740
Fred

[flintstone mop]

9PM Friday night
I'm listening to 740 AM from Toronto. Nice smooth audio. Reminds me of the 60's. Very nice bass and the high end is real. The bass is equalized for the sound from the 60's. The rumbling low end we hear from today's stuff wasn't invented during that time.
Looks really nice on the 'scope.
Not the squashed squeezed crappy 5KC audio from USA AM stations.

[W4AAB]

Wish I could null KRMG in Tulsa so I could get Toronto better. Most of my listening to broadcast radio is in the vehicle. With few exceptions, radio is a vast wasteland. Used to not be that way.
                                                   Joe W4AAB

[steve_qix]

I'm pretty sure the Canadian regulations don't limit bandwidth.  740 is CONSTANTLY interfered with by another Canadial station on 730 - and 730 is W I D E !!!!  Sometimes the sidebands from 730 render 740 completely unlistenable (is that a word?)..

[W2PFY]

unlistenable

 It's a word as far as  Dictionary.com is concerned

http://dictionary.reference.com/browse/unlistenable

[k4kyv]

I'm pretty sure the Canadian regulations don't limit bandwidth.  740 is CONSTANTLY interfered with by another Canadial station on 730 - and 730 is W I D E !!!! 

OTOH, the Canadian regulations DO regulate bandwith of amateur signals.  Supposedly, an AM signal is limited to a maximum of 6 kc/s occupied bandwidth.  But I have never heard of a Canadian ham being cited or harassed for running excessive bandwidth when transmitting a normal AM transmitter with normal audio.  I think most Canadians who run AM don't use any kind of special low-pass audio filter in the audio chain.

[kb3ouk]

Fred, the recording was made with a mic placed near the radios speaker(no way to directly  connect a 50's table top am?fm set to a computer). second, the hum i noticed on am740 is most likely IbOC, the night i made the recordings i heard the same kind of hum on WABCbut didnt heard it on AM740.

[W1AEX]

I have never paid much attention to 740 - AM but when I dialed them up last night they were quite strong into CT. It's a very pleasant music format for those of us who grew up in the 50's and 60's. 

At any rate, the BC band was rolling in and out and they came right up in the clear at around 11:30 PM. I caught a short station ID in the 12 second audio sample attached. The receiver was using the synch detector and the bandwidth was set to 16 kc. It actually sounded noticeably crisper when listening with a bandwidth of 20 kc, but the stations on 730 and 750 were strong enough to trash things, so that was not practical.

There are two local stations that play music in my area, but they don't come anywhere close to the sound produced by the transmitter at 740 AM. Sounds like they do it right!

[W2PFY]

Yes, that MP-3 station ID was honking!!! Almost sounded like a sixties jukebox Probably tube audio from the microphone to the PA    

[flintstone mop]

Not much audible on the AM band here that is not canned content.  Exceptions include WSM, Nashville, CJBC and CFZM in Toronto, and KRSN in Los Alamos, NM.  Except for WSM I get the others via streaming audio; I discovered CJBC 860 over the air back in the 60s, but now they are rarely entertainment quality here any more. CFZM is masked by some other station with a K callsign.

Most of what I hear when I scan the AM band at night is talk; primarily politics, sports and an occasional bible beater (all pretty much the same thing to me), and you can usually hear the same program on 5 or 6 different frequencies when tuning across the band, indicating that the stations have essentially turned into satellite repeaters. Sometimes while driving across the country I hear a few little local stations with somewhat hokey local programming, which can be interesting and entertaining for a brief  listen while passing through. I occasionally hear music, largely country and a  few rock oldies.  Rarely anything like jazz or classical.

The FM band is not much better.  Maybe a little more music and variety, but usually from a limited play list that runs over and over and over again, so that it gets tiring to listen to after about an hour.  And of course, plenty of endless strings of commercials in between the sets of a few songs.

I used to take refuge on short wave, but most of the good SWBC stations are now gone as well.  So about the only BC radio I listen to are a few non-commercials (the local NPR outlet and a couple of independent university stations). Even those may be falling by the wayside.  Vanderbilt University is considering selling their 60 y.o. FM outlet and going 100% streaming audio (not that it is actually costing them too much to run the station; they are looking at the revenue they would gain from the sale), while a small group of politicians are currently trying their damnedest to get rid of NPR.

WJIB (ex-WCAS) is taking an interesting approach.  I wish them continued success, although not my preferred music format.

http://www.wjib740.com/2.html

Some informative (cut-and-paste) links here
http://www.wjib740.com/3.html

On a similar thought of 'flipping' a radio license for profit was around 1980 in Washington DC. Georgetown University owned an FM license for their mismanaged 90.1 freq WGTB FM. Georgetown gave the license away to the University of The District of Columbia for $1, and the University of DC SOLD the very same license 2 yrs later to C-SPAN for $1.5 million. And the FECES granted a power increase to 50kw ERP.