you got to see read e ham " 40 meters what are you doing "

[flintstone mop]

Just an exercise - If we were to to consider eliminating AM from the VHF aircraft band, what phone mode would we institute there?

There's a real good reason for A.M. on the Aircraft band. Anybody want to take a good technical guess, why???

Fred

[W1ATR]

Just an off guess, but does it have to do with the capture effect FM xmitters on the same frequency will have with each other if they're close in sig strength? AM wouldn't suffer from this and multiple xmitters can be heard at the same time even if they're close in sig strength.

[W1AEX]

There's a real good reason for A.M. on the Aircraft band. Anybody want to take a good technical guess, why???
Fred

Yup. Any instances of doubling will be evident by the beating of the two signals. An indication that complete information might not have made it to the party that needs it, which is kind of important with tons of steel hurtling in many directions at high speeds in a small area.

I live within 5 miles of Bradley International and occasionally hear some funny stuff. One of my favorites went something like this:

Tower:  Proceed inbound on track 101 descending to 2000 feet. Commence level base turn left to intercept localizer, inbound track 270 Deg at 2000 feet. Descend on glide path to runway 6.

Aircraft:  What?

Tower:  Seriously?

Aircraft:  Nah, just kidding, I got it.

The corporate frequencies for the various airlines are always fun to listen to late at night. Lots of good-natured bantering going on between the flight crews and the staff.

[Sam KS2AM]

There's a real good reason for A.M. on the Aircraft band. Anybody want to take a good technical guess, why???

Fred

Because there ain't a slopbucket in North America that can bother it ?

[K1JJ]

Tower:  Proceed inbound on track 101 descending to 2000 feet. Commence level base turn left to intercept localizer, inbound track 270 Deg at 2000 feet. Descend on glide path to runway 6.
Aircraft:  What?
Tower:  Seriously?
Aircraft:  Nah, just kidding, I got it.

    Good one!

Another one: 


Tower: "Piper Arrow N1444X-ray, I have you 3 miles out with pattern traffic at 1000 feet - what are your intentions?"

Pilot:  "My intentions are to to land this crate and get drunk at the airport bar - wanna join me?"




(BTW, those were the neat call letters on my airplane years ago... what a lucky break)
Here it is for sale for $78K: 
http://www.aviatorshotline.com/avsearch.cfm?template=detail&AID=33825

[Steve - WB3HUZ]

I was on a plane once where the radio traffic went like this, as we landed.

Tower:  Is it cold in there?

Pilot: Damn cold!


The emergency exit door had blown off at 5000 feet over the Chesapeake Bay. We stacked up traffic at BWI for an emergency landing. Fun stuff.

[K1JJ]

I was on a plane once where the radio traffic went like this, as we landed.
Tower:  Is it cold in there?
Pilot: Damn cold!
The emergency exit door had blown off at 5000 feet over the Chesapeake Bay. We stacked up traffic at BWI for an emergency landing. Fun stuff.

If you were quick, you coulda saved some time by grabbing the handle and kite-boarding your way down, caw mawn.

(In addition to becoming vely, vely famous amongst the lugers and base jumpers)   

[KB1OKL]

The SSB'ers that hate AM say that AM is obsolete.

Back on page 1 I posed a question on what mode would you pick today for the VHF AM aircraft band, ignoring the totally impractical switchover mess.

Looking at all the voice modes including the new digital modes, listing all the quirks, advantages and disadvantages of each mode, you still come up with AM. 

Consider a total change to the AM broadcast band, same thing, you wind up with AM. 

Obsolete?  Fundamental.  How can fundamentals become obsolete?  Ignorance is never obsolete either.

Do you really believe that a viable and proven mode is immune to the current
thinking in Wa$hington???  Honestly?

http://tinyurl.com/cbw8zs

Considering what happened with the HD debacle here and the DAB debacle in Europe I wouldn't be worrying about that too much.

[KB1OKL]

Regarding the AM broadcast band, there has been a proposal by some in the industry to convert TV channel 6 into an extended FM band once the digital transition is complete, and allow AM daytimers and those with severely restricted night time power to move to the expanded portion, either using FM or digital-only. 

There is no movement to convert the AM BCB to digital, all there is is a stillborn effort by some of the big boy AM broadcasters to pollute the BCB with 50 KHz of hash in a 10 KHz space called IBOC. It is going over like a lead balloon and has been for about 5 years now (try to find a receiver). Digital FM has been enjoying about the same success rate.
Using channels 5 and 6 for BCB broadcasting has been brought up by those in the industry but it seems like a no go.

[k4kyv]

There is no movement to convert the AM BCB to digital, all there is is a stillborn effort by some of the big boy AM broadcasters to pollute the BCB with 50 KHz of hash in a 10 KHz space called IBOC. It is going over like a lead balloon and has been for about 5 years now (try to find a receiver).   Digital FM has been enjoying about the same success rate.

Just like AM stereo.

The vast majority of the public doesn't give a damn about audio quality, and besides, the rubbish that dominates the AM band these days could just as well be on slopbucket.

If people were very concerned about audio quality, the MP-3 format, like the old hissette tape format, never would have gained such wide acceptance.

The only thing about IBOC-FM that might possibly be a real selling point is the subcarrier  channels.  But there's not much worth listening to even on the main channel, and that is interrupted every 5 or 10 minutes with an endless string of commercials.  If "HD-FM Radio" really offers "CD quality", the improvement over the audio quality of a good solid analogue FM stereo signal would still be too subtle for the average Joe Bloe to even perceive, let alone to entice him to spend hundreds of bucks for a receiver while he can purchase a somewhat decent quality analogue set for $20.

Using channels 5 and 6 for BCB broadcasting has been brought up by those in the industry but it seems like a no go.

That's about the only "new" idea to come along to broadcasting lately that might actually improve the service.  The local and "graveyard" channels on the AM band could be moved to the expanded FM band, and actually see their coverage area increased both day and night.  That would free up the AM band for what it does best, regional broadcasting during the day and nationwide coverage at night via skywave.  The remaining AM stations could be spread far enough apart that sidebands from adjacent channels wouldn't overlap, giving everyone clear-channel coverage.

Remember how well the measly 1 kw nighttime signal from the station in Elizabeth, NJ covered half the continent with entertainment quality on 1660 kHz or thereabouts, while it was the first and only expanded-band AM signal on the air? Of course, this would work only if those remaining AM stations had original programming with local flavour, like WWL used to have and WSM still does to a certain extent.

But this whole idea makes too much sense from a technical standpoint and from a public-interest perspective, to be acceptable to FCC bureaucrats and corporate bean counters, so the idea was probably dead in the water from the outset.

[KA1ZGC]

Well, it's not like FM Stereo was ever "CD quality" anyway.

Pardon me, while I get out my Rabbit Maul. 

FM broadcast audio is brickwalled at about 15 kHz. Not only that, that's only your monoaural (L+R) product. Both exciters and receivers exhibit that characteristic, or you'd hear a nasty 19 kHz squeal on FM Stereo stations. 19 kHz is the stereo pilot tone, but at 38 kHz is the L-R subcarrier.

A CD can recreate actual stereo to 22 kHz, FM broadcast can only manage composite stereo out to 15 kHz. Still, you're right, the difference wouldn't really be noticed.

Anyway, transitioning to IBOC FM doesn't give you much more subchanneling ability than you already have. That was Muzak's primary means of distribution for years, they'd pay for a 50 to 68 kHz subcarrier on a big FM in a given metro. Other non-broadcast services have done the same. Sattelite and internet take care of that now.

Still, in this day and age, the greatest percentage of FM music listeners over any given hour are listening in their car. Few listen at home, and those listening at work never outnumber those on the road.

For the most part, that's a high-noise environment, which is why so many of those FMs compress as hard as they do. There are artists and producers in every genre that like to take full advantage of the 90+ dB SNR of a CD, which an FM channel can't match, and a car makes worse. Some stations way overdo it, I know.

The point is that IBOC is a solution looking for a problem. There's really no reason for stations to do it. For the most part, the improvements in audio will be unnoticed or inaudible, and you can't be picked up on any old AM/FM radio kicking around, which is what you want the most if you're a broadcast station. Their income is dictated by the number of ears on 'em, caw mawn.

When they find a way to make it more lucrative than the current system, it'll happen. That's just not the case now.

[Pete, WA2CWA]

The only thing about IBOC-FM that might possibly be a real selling point is the subcarrier  channels.  But there's not much worth listening to even on the main channel, and that is interrupted every 5 or 10 minutes with an endless string of commercials.  If "HD-FM Radio" really offers "CD quality", the improvement over the audio quality of a good solid analogue FM stereo signal would still be too subtle for the average Joe Bloe to even perceive, let alone to entice him to spend hundreds of bucks for a receiver while he can purchase a somewhat decent quality analogue set for $20.

Most of the HD FM sub-channels I listen to, have little to no commercials. The perceived audio quality is as good as a CD. On the main channel, I can manually switch between HD and regular signals and I hear a perceived difference in quality. How much, or how much better audio response there is, I don't really care. It sounds better in HD. Pricing for a typical home AM/FM HD tuner starts around $100. One of the great things I like, is that station with several sub-channels can have a wide assortment of programming (all rock, all country, all jazz, etc.) without having to tune up and down the band looking for it. Sensitivity also seems to be much better with a HD-type tuner. With only a small loop antenna for AM, during the evening  hours, 740 in Canada comes in like a NY station. AM stations in Chicago, Memphis, Denver sound also like locals. If you like AM DX'ing, you need one of these types of tuners. Blows the socks off the R-390A as far as AM in the broadcast band.

[WB2YGF]

Most of the HD FM sub-channels I listen to, have little to no commercials. The perceived audio quality is as good as a CD. On the main channel, I can manually switch between HD and regular signals and I hear a perceived difference in quality. How much, or how much better audio response there is, I don't really care. It sounds better in HD. Pricing for a typical home AM/FM HD tuner starts around $100. One of the great things I like, is that station with several sub-channels can have a wide assortment of programming (all rock, all country, all jazz, etc.) without having to tune up and down the band looking for it. Sensitivity also seems to be much better with a HD-type tuner. With only a small loop antenna for AM, during the evening  hours, 740 in Canada comes in like a NY station. AM stations in Chicago, Memphis, Denver sound also like locals. If you like AM DX'ing, you need one of these types of tuners. Blows the socks off the R-390A as far as AM in the broadcast band.

Agree with everything you say Pete but the sensitivity.  Like, HDTV, if I don't have a good signal, the HD cuts in and out, or I get nothing at all.  That said, my HD radio is a bedside clock radio not a professional tuner.  I enjoy the commercial free jazz from WWFM HD2.  It's enough value-added for me to justify the cost.

[Pete, WA2CWA]

Agree with everything you say Pete but the sensitivity.  Like, HDTV, if I don't have a good signal, the HD cuts in and out, or I get nothing at all.  That said, my HD radio is a bedside clock radio not a professional tuner.  I enjoy the commercial free jazz from WWFM HD2.  It's enough value-added for me to justify the cost.

Ah, but I have Sangean HDT-1X, besides the Sony XDR-S3HD table radio, that allows me to switch between analog and digital. Running the HDT-1X through the 70's 4 channel amplifier really rocks the basement better then 3885.

[KA1ZGC]

Since you're obviously familiar with the available product choices, how would you say the price compares with standard AM/FM tuners and tabletops that are otherwise similarly equipped?

Just curious what the differential is.

[W2ZE]

Since you're obviously familiar with the available product choices, how would you say the price compares with standard AM/FM tuners and tabletops that are otherwise similarly equipped?

Just curious what the differential is.

Alright, call me stupid, but I'll bite.

Right now there are 101 radio's being manufactured today by various manufacturer's. Distribution points include Best Buy, Wal-mart, Target, and before they crapped out Circuit City. Also radio's are being sold in smaller regional retailers. Many radio's are the after market car radio's, and also home theatre A/V systems.
The price point of many of these radio's is much higher than buying a comparable analog model, no doubt. It costs right now about 5 dollars to make an analog tuner with its chipset installed. An HD tuner costs anywhere from 13 to 17 dollars with chipset, and consumes about 50% more power. When the first HD tabletop tuner was introduced, it cost 27 dollars for the tuner and consumed double the power. As time marches on, the cost is reduced and power consumption will decrease. This I can tell you for certain is why you do not see a large proliferation of HD tuners in cars already installed from the factory. It costs alot of money to install, and needs to be tested and certified for proper operation; not only the tuner, but the chipset manufactured by the major chip makers (TI, Samsung, ST, SiPort). You may say to yourself, we'll 14 bux, thats not a big deal vs. 5 bux. Times 500,000 units sold, this adds up. This is why the big pushback when it was proposed that HD radio be installed in every Sat radio made after the XM sirius merger. It had nothing to do with HD itself, just the cost of manufacuring units. This would have prompted many auto makers to not install Sirius or XM as being cost prohibitive.
As far as products/applications are concerned: There are new chips being tested that are smaller and cheaper than ever before. Obviously, I cannot devulge what and who, but cost will be almost down to single digits, power lowered even more, and smaller tuners. devices are now being introduced built in to PND's (personal navi. dveices), and at the recent NAB, an armband radio that will cost around 40 dollars. The evil empire that is Clear Channel is seeing revenue from the iTunes tagging for iPod. to implement tagging, it cost them nothing but labor to enter the info.
A solution looking for a problem: Yes and no. There are still many issues needed to be worked out on the broadcaster side as well as the radio side, but as far as implementation, many big broadcasters have already installed HD Radio, and as seen at the NAB, smaller broadcasters are seeing the benefit as well. For as many vocal distracters we have , we have as amny silent supporters. Many people have come out and said that we need to goto a different solution or abandon the digital altoghter. FM eXtra is truly a solution looking for a problem, and having only 1 radio that isn't even commercially available. The recent NAB is evidence that there are many competeing factors to radio including mobile DTV introduced at the show. If radio dies a slow natural death, then so be it. I am going to go down swinging, rather than P&M about this, that and the other.
 If if 's and but's were candies and nuts, the we all would have a good xmas.

Mike, W2ZE

[AF9J]

Actually, TS-830S was also manufactured as the TS-830M (for non U.S. sales) that included AM. And, there was an optional board that could be purchased from Kenwood Parts that allowed AM (in the "Wide CW" mode switch position) in the TS-830S. An optional 6 KHZ AM filter could also be purchased and installed in the 830S when the AM board was installed. I believe only the 520, 530, 820, 830 series of rigs did not include AM as a standard offering. The Yaesu and, I believe, most of the Icom HF rigs included AM in their rigs. Domestically, Ten-Tec was a hold-out for a long time in not including AM in their rigs.

Yep, that's true Pete.  I have the FT-101's "evil twin" the FT-301, and it has AM.  As a matter of fact, in spite of being a solid state rig, it uses high level modulation in the form of collector modulation, completely bypassing the SSB & CW signal chain in the process.  It also has 6 kHz AM receive bandwidth too.  It'll do 30W of carrier.  I tried it for a laugh on 10m AM last year, and was surprised to get good reports on it's transmit audio (Tom, WA3KLR, was one of the guys I worked last year on 10m AM).  So much so, that it has become my high band AM rig, due to its frequency agility tuneupwise (I only have to peak up a preselector, and I'm good to go).

[Pete, WA2CWA]

There's nothing like listening to In-A-Gadda-Da-Vida, the long version, on HD Radio. Running it through the 4 channel decoder in the 4 channel amplifier with the volume cranked up. Drives the wife and dogs nuts.

With the Sony Radio pictured in my previous post, last year, Best Buy stores were clearing out their store stock. I was told they wanted to only carry their house brand version. Some stores cleared them out from a low of $39.95 to about $115 depending on the store. A quick Google search shows similar type models going for about $100 retail.

[k4kyv]

The price point of many of these radio's is much higher than buying a comparable analog model, no doubt. It costs right now about 5 dollars to make an analog tuner with its chipset installed. An HD tuner costs anywhere from 13 to 17 dollars with chipset...

Plus how much more to cover Ibiquity's licence fee?

[Opcom]

Regarding the AM broadcast band, there has been a proposal by some in the industry to convert TV channel 6 into an extended FM band once the digital transition is complete, and allow AM daytimers and those with severely restricted night time power to move to the expanded portion, either using FM or digital-only. 

There is no movement to convert the AM BCB to digital, all there is is a stillborn effort by some of the big boy AM broadcasters to pollute the BCB with 50 KHz of hash in a 10 KHz space called IBOC. It is going over like a lead balloon and has been for about 5 years now (try to find a receiver). Digital FM has been enjoying about the same success rate.
Using channels 5 and 6 for BCB broadcasting has been brought up by those in the industry but it seems like a no go.

I hate the IBOC on AM. I hear the digital hash from 4 to 5 KC like a fine tooth comb on my good Stromberg-carlson tube tuner when I listen to the oldies station. So now I do not listen to the station. I use the FM section and listen to WRR the classical station. The tuner was never bothered by the old QAM AM signal. Fortunately for the AM station, most of their listeners do not have top grade analog AM tuners. I would consider a IBOC receiver, but WTH? some of those old records were never in stereo, yet the station has "stereo-ized" them and ruined it, and done it is such a way that you can't combine the IBOC channels back to one without it sounding weird, and turning the IBOC off renders the radio too narrow and dull, as the basic receiver part is less than 4KC wide somewhere in there, so the hash is not heard when IBOC is turned off. What I might be interested in is an outboard IBOC demodulator to try and use with my good tuner, but that's a nogo, since the whole decoder thing is licensed and patented etc.

[Tom WA3KLR]

I've been listening across the BC band late night.  What a shame the IBOC signals are trashing reception.

[Pete, WA2CWA]

I've been listening across the BC band late night.  What a shame the IBOC signals are trashing reception.

Don't seem to have that problem with the HD receiver.

[Opcom]

when you don't have this problem, is the IBOC being received, or not being received 9due to night time power cutbacks)?