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Saving AM Radio

I can attest to this to an extent.

For example, KCBS sounds pretty bad in the car (muffled and difficult to hear if we're driving on a noisy road), but I can tune it in on my Sony SRF-A100, and even in DX/narrow mode, it sounds quite a bit better (it sounds fantastic in local/wideband mode, of course).

So with a decent receiver, stations can still sound OK. Even the less good sounding ones can sound better.


In practice, yes.

Under "laboratory" conditions, though, I've found that, again, in wideband stereo mode on my SRF-A100, my Part 15 actually sounds really good. Almost as good as FM, in my opinion (it helps that I have taken great pains to ensure that my processing sounds as good and as transparent as it can, which has taken much trial and error because I learned as I went). I also broadcast in stereo, so that makes a difference too (everything sounds better in S-T-E-R-E-O!!! 😛).

On my car's radio? It sounds about as muffled and indecipherable as KCBS does, so is all that time and effort spent on processing (and transmitting in stereo) a waste? Maybe so, but not to the one or two other people who might care to listen in on a decent receiver.

c
It's so sad that so many who think that AM always sounds bad, have probably never in their life heard it through a hi-fi receiver, such as the Sony you mentioned. (I have one too). In the past I remember someone on this forum state, as if it were established fact, that "anyone who thinks that AM sounds anywhere near as good as FM, needs to have their hearing checked". People who say this should try to get a Sony-A100 or the Walkman version or maybe a Sansui TU-D99AMX tuner and plug it into their sound system, if they have one. Or buy a good GE-Superradio model that has dual bandwidth and hear what you've been missing!

BTW, I concur with your thoughts on KCBS. I live in SoCal. At night when KCBS is strong through that Superradio, KCBS sounds like the studio might be in the next room! I might go so far as to say they sound a bit better than LA's KNX News 97.1, which I believe is due to their processing. KNX 1070 has never sounded as good as KCBS 740. KNX's FM sounds like it gets the same processing that the AM does.
 
The AM section in late model GM vehicles actually does a fine job in regards to dynamically adjusting the bandwidth. The ACG characteristics do a good job as well. I was just in the car a minute ago listening to KNX and KFI several hundred miles away, and it really was pleasant.
 
It's so sad that so many who think that AM always sounds bad, have probably never in their life heard it through a hi-fi receiver, such as the Sony you mentioned. (I have one too).
Yes, definitely. The SRF-A100 is a very nice little radio that sounds fantastic in wideband and stereo mode (it sounds average in normal mode, but even that sounds better than most newer stuff). I also have the boombox version, the CFS-6000. It uses the same tuner circuitry as the A100, as it has the same feature set and sounds similarly good, maybe a little better, even. It also has a cassette recorder that I fixed up so I can be record stations I'm listening to the old fashioned way (I have a bunch of NOS 120 minute tapes I bought for that very reason!)

Anyway, what this has shown me is that, given the current state of affairs, there was once a time in the not-too-distant past where at least some radio manufacturers actually tried to make at least some of their radios sound good on all bands.

I heard someone being interviewed on KCBS today (on AM, of course :) ) who said that the companies that supply drug stores with the generics that they put their own branding on don't really care much about quality anymore, instead putting money first. This, he claimed, was a significant reason why statisics show that the generic, house brand products have a higher recall rate than their name-brand counterparts.

I'd argue that this metality (putting profits before quality) has become quite prevalent over the past 5 or so years, and is making everything seem worse.

In other words, we're paying more for mediocrity.

c
 
At least with the DSP-based radios, I've found that reducing the bandwidth ameliorates the weird behavior with some AM stations. Often a station that sounds bad with a 6 kHz bandwidth will sound just fine at 3 or 3.5 kHz.
On my Tecsun PL-310ET on KNBR it's going Faded in & Out, But when I set the Bandwidth at 3 KHz it's Normal
 
Under "laboratory" conditions, though, I've found that, again, in wideband stereo mode on my SRF-A100, my Part 15 actually sounds really good. Almost as good as FM, in my opinion (it helps that I have taken great pains to ensure that my processing sounds as good and as transparent as it can, which has taken much trial and error because I learned as I went). I also broadcast in stereo, so that makes a difference too (everything sounds better in S-T-E-R-E-O!!! 😛).
I'm sorry, but that's such a B.S. argument. We don't live in a 'laboratory environment' where there is no noise, no bandwidth limits, and no need to compress and clip the crap out of the audio. In other words, you're doing nothing more than comparing what amounts to fantasy land, versus real.
 
On my Tecsun PL-310ET on KNBR it's going Faded in & Out, But when I set the Bandwidth at 3 KHz it's Normal
I've been told that the KNBR (680) antenna system can't pass much more bandwidth than a normal frequency response. And it's true that KNBR never ran IBOC HD on AM, which would have required a wider frequency response, even though its co-owned station KTCT ("KNBR 1050") did. So that relatively narrow-banded performance could have something to do with it.
 
I've been told that the KNBR (680) antenna system can't pass much more bandwidth than a normal frequency response. And it's true that KNBR never ran IBOC HD on AM, which would have required a wider frequency response, even though its co-owned station KTCT ("KNBR 1050") did. So that relatively narrow-banded performance could have something to do with it.
Does KTCT duplicate the programming of KNBR? 680 seems to have a pretty good coverage map all it's own.
 
I'm sorry, but that's such a B.S. argument. We don't live in a 'laboratory environment' where there is no noise, no bandwidth limits, and no need to compress and clip the crap out of the audio. In other words, you're doing nothing more than comparing what amounts to fantasy land, versus real.
I know that!

I'm just pointing out that AM technology can sound good under very unlikely ideal conditions. Fantasy? Probably, but I know that real-world conditions are never even remotely that good, so my expectations are realistic.

c
 
Does KTCT duplicate the programming of KNBR? 680 seems to have a pretty good coverage map all it's own.
KNBR (680) is a class-A station, what was once referred to as a clear-channel station. KTCT (1050) is 50 kw but directional at night. It exists primarily for overflow events - i.e. the San Francisco Giants always take precedence on KNBR, so if there's another event that KNBR would otherwise carry but conflicts with the Giants, the other event goes on KTCT - and to clear syndicated sports talk shows.
 
On my Tecsun PL-310ET on KNBR it's going Faded in & Out, But when I set the Bandwidth at 3 KHz it's Normal
If you have it at a higher bandwidth to begin with, the radio will be a little less sensitive. Narrower bandwidth = better sensitivity. My Tecson PL-398 does the same thing. On AM I usually have it set at 3 kHz or 2 kHz.
 
If you have it at a higher bandwidth to begin with, the radio will be a little less sensitive. Narrower bandwidth = better sensitivity. My Tecson PL-398 does the same thing. On AM I usually have it set at 3 kHz or 2 kHz.
You make a great point that's been completely missed on this thread. Certainly, nobody would be interested in doing so at this stage in time, but given the increase in noise on the MW band, narrow-banding transmissions would add an advantage to what's left of AM reception. In other words, put all the energy transmitted into a single sideband and narrow the filters in modern SDR receivers to receive in SSB. Like SSB everywhere else, I'd bet reception would improve by 25-30% on average. It would still sound like poo, but for voice grade, which is most of what the AM band features anyway.
Leonard Kahn did something like this back in the late 80's with what was left of his AM stereo exciters. He modified a few to modulate one sideband more than the other and called it the "Powerside". KOA in Denver, CO. was his test mule. I checked it out back in the day, and KOA was more receivable at the fringes with asymmetrical sidebands than when operating symmetrically. The problem was it required a capacitive slide-rule tuning radio. Modern digital SDRs that tune to the center won't work.
 
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Powerside worked quite well for many stations. Synchronous detectors work well. DSP and SDR really do magic. There are some AM stations out there that really do sound good, but many do not. And I wish folks would spend a little time rectifying the poor audio some of these stations are transmitting.
 
You make a great point that's been completely missed on this thread. Certainly, nobody would be interested in doing so at this stage in time, but given the increase in noise on the MW band, narrow-banding transmissions would add an advantage to what's left of AM reception. In other words, put all the energy transmitted into a single sideband and narrow the filters in modern SDR receivers to receive in SSB. Like SSB everywhere else, I'd bet reception would improve by 25-30% on average. It would still sound like poo, but for voice grade, which is most of what the AM band features anyway.
Leonard Kahn did something like this back in the late 80's with what was left of his AM stereo exciters. He modified a few to modulate one sideband more than the other and called it the "Powerside". KOA in Denver, CO. was his test mule. I checked it out back in the day, and KOA was more receivable at the fringes with asymmetrical sidebands than when operating symmetrically. The problem was it required a capacitive slide-rule tuning radio. Modern digital SDRs that tune to the center won't work.
This sounds a lot like AM compatible SSB, which was used by some shortwave broadcasters in the 1990s. Transmit only one sideband and slightly reduce the carrier. Apparently sounded great on receivers with synchronous detection capabilities. Radio Netherlands did this on one of its North American beam frequencies from Bonaire for a few years. On a regular receiver spoken word sounded fine but music would occasionally be a bit rough. RN eventually dropped this transmission mode, not sure why…might have been more of a prof of concept experiment.
 
Allow 1000w stations to go to 5kw.
Allow 5000w stations to go to 25kw.
Turn off the HD signals. They don't improve the sound enough to bother and most people don't even know it's there and most importantly....the interference caused by the digital side bands is unjustified.
 
Allow 1000w stations to go to 5kw.
Allow 5000w stations to go to 25kw.
The problem is that such a move would cause immense interference at night when higher powered stations would chew up any increased coverage of other co-channel stations.
Turn off the HD signals. They don't improve the sound enough to bother and most people don't even know it's there and most importantly....the interference caused by the digital side bands is unjustified.
There are now less than 100 AM stations using AM HD out of over 4000 licensed AM stations in total. Turning them off won't help anything.
 
The problem is that such a move would cause immense interference at night when higher powered stations would chew up any increased coverage of other co-channel stations.

There are now less than 100 AM stations using AM HD out of over 4000 licensed AM stations in total. Turning them off won't help anything.
The poster is from the Hartford area. Is WTIC still splattering 1090 and 1070 with its IBOC hash?
 
Allow 1000w stations to go to 5kw.
Allow 5000w stations to go to 25kw.

The problem is that such a move would cause immense interference at night when higher powered stations would chew up any increased coverage of other co-channel stations.

Which would then make it more necessary to take more AM stations permanently silent. Be careful what you wish for?
 


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