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A large number of factory-optioned HD-capable radios are only available as part of a VERY pricey entertainment and navigation package. In Mercedes-Benz cars the HD-included bundle runs from $3500 to $8000. In Jaguar it's over 3K. Even Ford's HD bundle approaches $1K.
The Ford Sync system, OTOH, is a really cool and capable option. It does a lot of thing very well, and very intuitively, seamlessly melding cell tech, internet access and music from a variety of sources including radio. Given the choice most consumers will opt for Sync in vast preference to an additional expenditure for weakly-performing, interference-addled HD.
The Ford Sync system, OTOH, is a really cool and capable option. It does a lot of thing very well, and very intuitively, seamlessly melding cell tech, internet access and music from a variety of sources including radio. Given the choice most consumers will opt for Sync in vast preference to an additional expenditure for weakly-performing, interference-addled HD.
Don Juannn said:Nope. It works fine. And after the power increase it will work even finer. ;-)
Well, it works fine under certain conditions. You need a specific threshold to get above the noise level, and the blanket "so many db below the carrier" doesn't cut it. Consider two stations, both with theoretically the same Analog coverage. One is 50,000 watts at 500 feet. The other is 4,000 watts at 1580 feet. These are two real stations, both running HD. Their injection level is -20 dbc. The station with the lower elevation is running HD at an RMS carrier power of 500 watts. It provides an effective HD signal, locking in most vehicles, out to about 30 miles in flat terrain. The station with the higher elevation, however, has superior FM multipath performance in analog mode and can easily be heard on car radios 50 miles away. The HD signal, at 40 watts, drops below the noise threshold of the average HD receiver just a few miles from the transmitter. It's physics, and the signal diminishes as 1/r-squared. So even though the higher transmitter is still line-of-sight to the receiver the HD signal is gone.
So bring on a power increase. Yes, that can help. But the average signal variation in a moving vehicle is on the order of 20 db (we've all noticed bad reception at a stoplight, and you move forward a foot & the signal is good, right?) So even with a full 10 db increase that only brings the high-transmitter signal up to 400 watts, and the HD coverage approaches that of the lower-elevation transmitter. Now, realistically the increase will be 4 db because nobody in those sparsely-populated areas (where they can go up 10 db) is going to shell out the $$ for the high-powered transmitter just so the prairie dogs can hear HD.
Consider also the development of receivers. The new Lexus sports an FM Diversity radio with an unbelievable noise figure. It's actually two radios in one, connected to two antennas. It samples the noise around the pilot carrier and switches to whichever antenna is receiving the best signal. No more stoplight fades. I rode in one last weekend to Lake Tahoe and we listened to KVMR (Nevada City, CA - check out the theoretical coverage map) from Stockton, CA to Kirkwood along highway 88. This is WAY out of their predicted contour and in mountainous terrain, yet the signal was clean for pretty much the entire trip. There's strong stations on 89.7 (in Lodi) and 89.3 (in the hills East of Stockton) but the Lexus radio didn't care.
Interestingly enough, KVMR can't be heard clearly much closer to their transmitter in Sacramento, because there's a station on 89.3 running HD. It's now seven years since HD first appeared in the San Francisco market, and the number of listeners deprived of signals due to interference still far exceeds the number of listeners capable of hearing HD. It was a noble effort, but let's face it - digital needs a new radio band.
Dave B.
D
Don Juannn
Guest
Savage said:A large number of factory-optioned HD-capable radios are only available as part of a VERY pricey entertainment and navigation package.
Same way FM came into being a stock item.
Don Juannn said:Savage said:A large number of factory-optioned HD-capable radios are only available as part of a VERY pricey entertainment and navigation package.
Same way FM came into being a stock item.
The main issue with FM was the licensing fee, and ironically the Armstrong patent ran out about the exact same time that the FCC mandated separate programming for AM & FM. So manufacturers could add FM for a couple of bucks, where before it cost a lot more.
Savage said:I suppose so. If you choose to ignore all the lying. And all the destructive interference to undeserving neighbor-broadcasters.
Good point, although I think most of the deceit and desperation came after Ibiquity realized that their system didn't really work as advertised, but they had to do something to protect their investment. When I first heard the phrase "in band on channel" I thought that's what it actually was - embedded within the assigned channel along with the analog audio. They do it with WiFi, why not radio, right? Boy, was I wrong.
Dave B.
According to TheBigA (in Reply # 84, on 11/17/2010):
Actually, Armstrong’s patents on wideband FM and the circuits to implement it were filed in 1933, and expired in 1950. He began filing infringement suits in 1951, and these would only allow him to collect royalties and damages for infringements during the last six years that the patents were still in force. Several were settled before his death—but for royalties only—because the smaller companies knew the patents were valid.
My first point here is that, from 1951 on, patent royalties were no obstacle to the growth of FM.
But my second point, no less important, is that the “50/50 rule” was established only in 1967, which was when the first “baby boomers” were coming of age and turning away from Top 40 to “album rock.”
And let’s not forget that it was also in 1967 the major record labels decided to stop issuing new releases in mono. And FM, like the turntable, offered stereo.
Still, lots of teenagers at home and college students in dorm rooms could only listen to small mono FM radios—though they all wanted component stereo systems, not the stereo consoles (“fruitwood boxes”) in their parent’s living rooms. But it’s just as well that those in the outlying susburbs were listening in mono, because the weaker signals that some of the groundbreaking stations had in those days would have been too noisy in stereo twenty miles away from the transmitter.
Why? Because the system adopted in 1961 uses an AM (actually DSBSC) subcarrier for the stereo difference. An FM subcarrier would yield far better performance. Armstrong himself said this:
The triangular noise spectrum of FM yields a lot of noise in the range used by the stereo difference signal—far too much noise for an AM signal when the main carrier is weak. An FM subcarrier system, which can use limiters to suppress such noise, is much better.
So, too, is a digital subcarrier system. That’s why FM Extra is so superior to Iniquity’s “HD” radio system!
The main issue with FM was the licensing fee, and ironically the Armstrong patent ran out about the exact same time that the FCC mandated separate programming for AM & FM. So manufacturers could add FM for a couple of bucks, where before it cost a lot more.
Actually, Armstrong’s patents on wideband FM and the circuits to implement it were filed in 1933, and expired in 1950. He began filing infringement suits in 1951, and these would only allow him to collect royalties and damages for infringements during the last six years that the patents were still in force. Several were settled before his death—but for royalties only—because the smaller companies knew the patents were valid.
My first point here is that, from 1951 on, patent royalties were no obstacle to the growth of FM.
But my second point, no less important, is that the “50/50 rule” was established only in 1967, which was when the first “baby boomers” were coming of age and turning away from Top 40 to “album rock.”
And let’s not forget that it was also in 1967 the major record labels decided to stop issuing new releases in mono. And FM, like the turntable, offered stereo.
Still, lots of teenagers at home and college students in dorm rooms could only listen to small mono FM radios—though they all wanted component stereo systems, not the stereo consoles (“fruitwood boxes”) in their parent’s living rooms. But it’s just as well that those in the outlying susburbs were listening in mono, because the weaker signals that some of the groundbreaking stations had in those days would have been too noisy in stereo twenty miles away from the transmitter.
Why? Because the system adopted in 1961 uses an AM (actually DSBSC) subcarrier for the stereo difference. An FM subcarrier would yield far better performance. Armstrong himself said this:
“This latter method of multiplexing [with an FM subcarrier] has obvious advantages in the reduction of cross modulation between the channels and in the fact that the deviation of the transmitted wave produced by the second channel is constant in extent, an advantage being gained thereby which is somewhat akin to that obtained by frequency, as compared to amplitude, modulation in simplex operation.”
From “A Method of Reducing Disturbances in Radio Signaling by a System of Frequency Modulation,” by Edwin H. Armstrong, Department of Electrical Engineering, Columbia University. Proceedings of the Institute of Radio Engineers, Volume 24, Number 5 (May 1936).
The triangular noise spectrum of FM yields a lot of noise in the range used by the stereo difference signal—far too much noise for an AM signal when the main carrier is weak. An FM subcarrier system, which can use limiters to suppress such noise, is much better.
So, too, is a digital subcarrier system. That’s why FM Extra is so superior to Iniquity’s “HD” radio system!
radioskeptic said:My first point here is that, from 1951 on, patent royalties were no obstacle to the growth of FM.
His widow continued to pursue legal challenges until 1967. Until that time, other major manufacturers stayed away.
I remember trying to listen to WBCN 104.1 FM in 1968 on my friend's parents console when I was 15, (yes in the living room) it was the first "underground" station on FM at that time, before that there was only very boring lite symphonic stuff on FM, boring for us kids anyway. The reason FM starting taking off was because programming was put on for the kids and hippies and wanna be hippies of that time which was not available anywhere else, no other reason no matter what anyone here says. The gradual conversion to FM was driven by a cultural revolution. Even my local rock n roll AM station, WORC 1310 starting playing stuff like The canned Heat in 1968 with a lead in jingle that said "Worcestertown Underground". Of course that would be followed by something like Engelbert Humperdinck. FM didn't have to try to gradually change to the new styles, it didn't have an audience that had to be spoon fed the new styles like AM was now burdened with. I started buying FM equipment just to listen to this burgeoning revolution on FM. Anyway it didn't come in well here at approx 35 miles from the transmitter. Of course it came in better than HD comes in now on MUCH better receivers.
KB1OKL said:The reason FM starting taking off was because programming was put on for the kids and hippies and wanna be hippies of that time which was not available anywhere else, no other reason no matter what anyone here says. The gradual conversion to FM was driven by a cultural revolution.
So what you're saying is that all HD has to do is play obscure music that a small minority likes, and it'll take off just like FM?
I said, “My first point here is that, from 1951 on, patent royalties were no obstacle to the growth of FM.”
And TheBig A replied, “His widow continued to pursue legal challenges until 1967. Until that time, other major manufacturers stayed away.”
Yes, the estate continued to pursue back royalties (as well as punitive damages) for equipment manufactured prior to the 1950 expiration of the patents. I know of no cases extending into the 1960’s. (Can you cite any? I didn’t think so.) But that was no obstacle to the marketing of new FM receivers after the patents expired.
And the suit against RCA, which had been filed in 1948, was settled within a year of Armstrong’s death. (I was referring above to the suits against other, smaller infringing firms that Armstrong began filing in 1951, but those were only for infringements prior to the 1950 expiration of his patents.)
The suit against RCA, which had been filed in 1948, was settled within a year of Armstrong’s death. In a previous post, I was referring to the suits against other, smaller infringing firms that Armstrong began filing in 1951; but those, too, were only for infringements prior to the 1950 expiration of his patents.
Yes, the estate continued to pursue back royalties (as well as punitive damages) against a few other companies for equipment manufactured prior to the 1950 expiration of the patents. I know of no cases extending into the 1960’s. (Can you cite any? I didn’t think so.) But royalties couldn’t be charged for newer radios, so those lawsuits presented no obstacle to the marketing of new FM receivers after the patents expired.
And TheBig A replied, “His widow continued to pursue legal challenges until 1967. Until that time, other major manufacturers stayed away.”
Yes, the estate continued to pursue back royalties (as well as punitive damages) for equipment manufactured prior to the 1950 expiration of the patents. I know of no cases extending into the 1960’s. (Can you cite any? I didn’t think so.) But that was no obstacle to the marketing of new FM receivers after the patents expired.
And the suit against RCA, which had been filed in 1948, was settled within a year of Armstrong’s death. (I was referring above to the suits against other, smaller infringing firms that Armstrong began filing in 1951, but those were only for infringements prior to the 1950 expiration of his patents.)
The suit against RCA, which had been filed in 1948, was settled within a year of Armstrong’s death. In a previous post, I was referring to the suits against other, smaller infringing firms that Armstrong began filing in 1951; but those, too, were only for infringements prior to the 1950 expiration of his patents.
Yes, the estate continued to pursue back royalties (as well as punitive damages) against a few other companies for equipment manufactured prior to the 1950 expiration of the patents. I know of no cases extending into the 1960’s. (Can you cite any? I didn’t think so.) But royalties couldn’t be charged for newer radios, so those lawsuits presented no obstacle to the marketing of new FM receivers after the patents expired.
TheBigA said:KB1OKL said:The reason FM starting taking off was because programming was put on for the kids and hippies and wanna be hippies of that time which was not available anywhere else, no other reason no matter what anyone here says. The gradual conversion to FM was driven by a cultural revolution.
So what you're saying is that all HD has to do is play obscure music that a small minority likes, and it'll take off just like FM?
No for two reasons: FM worked and we were not a small minority.
KB1OKL said:No for two reasons: FM worked and we were not a small minority.
The ratings say otherwise.
TheBigA said:KB1OKL said:No for two reasons: FM worked and we were not a small minority.
The ratings say otherwise.
I don't care about ratings, were you there?
KB1OKL said:I don't care about ratings, were you there?
If you're going to say "we were not a minority," then you need to care about ratings.
The fact was that these progressive rock stations didn't get any ratings until they became more mainstream in the mid-70s.
So to say stations like WBCN is why FM took off ignores the fact that the vast majority of people didn't listen to the station.
If you're going to identify programming as a reason for the success of FM, I'd suggest WBZ-FM or WRKO-FM.
I have to completely agree with OKL. On the technical side FM analog works, HD doesn't. On the programming side, the coming-of-age of the baby boomers, the advent of progressive/underground/album rock, a cultural revolution brought on by the Vietnam War, and a bunch of underutilized FM stations (that worked) sitting in the wings made for the perfect storm. The HD content of today is no better than that of FM analog (in most cases identical), and in most of the HD2/3/4 cases it's worse. Anyway, discussing the relative merits of content on HD is an exercise in futility because HD is an abject technical failure. Great content can't flow through a pipe that is both plugged (poor coverage and bandwidth) and leaky (interference) -- not to mention expensive.
And, OKL, I noticed your question went unanswered by BigA! By the way, I was there -- 20 years old and a junior at a major university in 1968.
And, OKL, I noticed your question went unanswered by BigA! By the way, I was there -- 20 years old and a junior at a major university in 1968.
radioskeptic said:I know of no cases extending into the 1960’s. (Can you cite any? I didn’t think so.)
Their lawyer says the lawsuits continued until 1967. They won 20 of the 21.
radioskeptic said:But that was no obstacle to the marketing of new FM receivers after the patents expired.
Apparently it was, because few major manufacturers, especially American owned companies, included it. What changed everything was when Japanese companies began including FM in their portables. That happened in the mid 60s. I imagine part of that was because of the international market.
I read somewhere that RCA continued to refuse to add FM to its radios until after Sarnoff retired in 1970.
local oscillator said:I have to completely agree with OKL. On the technical side FM analog works, HD doesn't. On the programming side, the coming-of-age of the baby boomers, the advent of progressive/underground/album rock, a cultural revolution brought on by the Vietnam War, and a bunch of underutilized FM stations (that worked) sitting in the wings made for the perfect storm.
You can agree all you want. The fact is that underground music wasn't popular. Thus the name "underground."
It wasn't until mainstream music moved to FM, which was the early 70s, that FM started to take off.
TheBigA said:KB1OKL said:I don't care about ratings, were you there?
If you're going to say "we were not a minority," then you need to care about ratings.
The fact was that these progressive rock stations didn't get any ratings until they became more mainstream in the mid-70s.
So to say stations like WBCN is why FM took off ignores the fact that the vast majority of people didn't listen to the station.
If you're going to identify programming as a reason for the success of FM, I'd suggest WBZ-FM or WRKO-FM.
I had written "started" in case you missed it, it was all downhill from there.
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