Each U.S. (and Canadian, and Mexican) TV station has been assigned a 6MHz chunk of spectrum for their analog signal. They can transmit a single program stream in this spectrum.
More recently, each station in these three countries has also been assigned a second 6MHz chunk for digital operation.
It is possible to transmit more than one program stream in this spectrum.
In the U.S., stations are required to transmit at least one standard-definition program stream in this spectrum. This is what KLEP (the station mentioned in the link) is saying they can't afford to do.
U.S. stations may optionally choose to transmit additional program streams. It's these optional additional streams cable has not been required to carry when they exist.
(I do believe the failure of the FCC to require carraige of the additional streams is a mistake that will make it difficult for many smaller stations to finance digital conversion)
I think the "indecency police" have gone too far, but I don't see any inconsistency in expecting satellite radio and broadcast radio to live by the same rules. (likewise cable and broadcast TV) With well over 80% of homes having cable or satellite, does it accomplish anything to keep Janet's nipple off CBS when it's perfectly legal to show it on MTV?
"In short: greedy broadcasters tricked Congress into giving them free spectrum for a second set of digital channels, so that Americans who bought digital TVs would have something to watch. Then they did nothing with them. "
This spectrum was hardly free, and it's very much not true that stations aren't doing anything with the second channels.
The station I work for had to:
Install a temporary transmitting antenna for the analog signal.
Remove the original analog antenna.
Chop off the top 30m of the tower. (so that when the new antenna was added the total height of the structure wouldn't be any greater)
Fasten the original analog antenna to the top of a new digital antenna, and hoist the whole thing to the top of the tower.
Remodel a room in the transmitter building to accept the new digital transmitter.
Buy and install a second transmitter for the digital signal.
Purchase and install various ancillary equipment - an upconverter so we can transmit our local programs over the digital transmitter when the network isn't offering high-definition programs; switching equipment to go between the network and upconverted local material; monitoring gear; fiber-optic equipment to send programming from the studio to the transmitter, etc., etc.
Not cheap. And we lucked out by drawing RF channel 10, meaning we could run 42 kilowatts of power as opposed to our competitors who need 1000 kilowatts to achieve the same coverage. I don't want to know about their electric utility bills!
This is an expense imposed on these stations. Even if your business plan doesn't have room for high-definition. Even if your business plan depends on multicasting. (multiple programs over the same transmitter -- the FCC has decided cable is not required to carry the additional programs, making multicasting economically impractical.)
The stations' other alternative: do nothing with their second channel, and know that at some future point, they will be forced to surrender their license and go out of business. (At least one station already has.(scroll down to "1993+"))
"Meantime, cops and firefighters and EMTs are (literally) dying for some of that squat-upon spectrum so that they can coordinate their rescue efforts."
IMHO there is no shortage of available public-safety spectrum. The two-way radio manufacturers know that each time a new chunk of public-safety spectrum is opened, they'll sell thousands if not millions of new radios. The old 150MHz and 460MHz bands are being abandoned in droves - but are perfectly suited for public-safety work. (the old 40MHz band has been so fully abandoned that the FCC feels safe in allowing special temporary use for a FM broadcast station commemorating Armstrong's original FM experiments in New York City...)
If we were talking about £100 ($190) or something I'd be more inclined to agree with you...
That $190 figure is pretty close to accurate, for what the least-expensive set-top box is selling for in the States.
It seems some viewers are pretty sensitive to MPEG artifacts; others (me!) don't notice them unless they're serious. Personally I think the improvement in quality is indeed pretty dramatic, even on a standard-definition display.
It's not entirely clear whether Congress meant for this 85% figure to include people who are watching digital programs on analog recievers after having them downconverted by their cable/satellite company. Some argue that it doesn't, in which case the 85% figure will likely never be met.
(even if cable/satellite subscribers are included, subscribership varies wildly from place to place with some cities having as much as 30% off-air viewership.)
Virtually nobody actually believes analog will shut down in 2006.
" Hardy acknowledged, however, that the indices are not complete. "The FBI does not index every name in its files," Hardy told the court. Other than the subject, suspects and victims, names in FBI files are indexed at the discretion of the investigating agent and supervisors if they are "considered pertinent, relevant or essential for future retrieval." "
If a deficient index makes it impossible to answer FOIA requests from outside personnel... doesn't it also make it impossible to answer internal requests from the FBI's own agents? What happens if the investigating agent misjudges the relevance of a name to future investigations?
It may be possible to observe the radio effects of the meteor shower without being a ham or having an extensive station.
Regular FM radio and TV broadcasts are also reflected by the ionized trails.
Try tuning to an empty channel, as low on the dial as possible. Of course, for TV you'll need a set with a regular antenna, not cable or satellite. For FM, your car radio is probably the best radio you own for this purpose.
Sit there and listen/watch. You should see/hear brief bursts of signal. If you're really lucky, you'll hear something that will allow you to identify the station you saw/heard.
Might be something interesting to listen to while you're waiting for visible meteors -- or for the clouds to go away...
I have numerous passwords imposed from outside. Let's see:
Root on two Linux boxes
Administrative accounts on the above boxes (for when work requires more permission than an ordinary user but doesn't require root. Several other people share responsibility for these accounts.)
My regular user account on these systems.
Corporate domain account, into which I must login to access the machine on my desk
Local administrator password on Windows XP desktops, necessary as I'm responsible for occasionally installing software. Corporate changes this every 60 days, but sometimes it doesn't work so you're never too sure when you may need to use an old password - and which one
Four additional server systems, administered by various vendors and each requiring its own password.
My machine at home
My Earthlink account password
My ATM PIN code
etc.....
Point is, many users don't have only one set of passwords to remember - they have many. Some at work, some at home.
Demanding regular changes to securely-chosen passwords is simply not humanly possible. If you were to steal my wallet, you'd find at least three of my passwords... (no, not my ATM PIN!)
...must pay $25,000
and put an end to the practice,...
(emphasis mine)
I guess that means if he decides to spam again, Massachusetts can reopen the case and seek more damages.
I wonder (not being a lawyer) whether a contempt citation and jail time would be an option if one were to repeatedly refuse to live up to a settlement?
Digital satellite and cable are considerably more compressed than most OTA digital TV.
That said, some people seem far more sensitive to MPEG artifacts than others. (just like some people think MP3s have unlistenable distortion, while others can't tell the difference from the uncompressed source)
...which couldn't be done as well at the higher frequencies to which the TV networks are being moved. (I believe that has to do with the better penetration capability of the lower frequencies, while the relatively immobile TV receiver can use an exertnal antenna. But I'm not certain of this.)
Basically, television is being compressed into a smaller chunk of spectrum.
Under the old rules, TV used channels 2-69. When the digital conversion is complete, channels 52-69 will be removed from TV service. Four of those channels will be used for public safety; the rest will be auctioned.
I suppose on average, TV is being moved to *lower* frequencies. However, in many cases individual stations are moving *higher*. This is usually because when a new station is built, it prefers to use the lowest available channel. (oversimplification but reasonable) So, when time came to allocate second channels for digital, the channels that were most likely to be available were higher channels.
After analog is closed, stations will be allowed to move their digital operations to their current analog channels. The Nashville PBS station that currently operates on digital channel 46 will be allowed to move its digital operation to their current analog channel 8.
Higher frequencies penetrate buildings better, while lower ones cover a greater distance for a given amount of transmitter power. Lower frequencies also require larger antennas. (not good for, say, the handheld radio on a police officer's belt!)
Subchannels are a mixed blessing. Programming is VERY expensive to produce. In many cases it may be impossible to raise enough extra revenue by carrying two extra games to cover the cost of the rights to those games.
The area over which a radio transmission causes interference is far larger than the area over which it provides useful service. For example, according to the FCC, WSM-FM in Nashville provides service over a radius of 79km around their tower. WSM-FM would interfere with another station on the same frequency within 182km of the tower.
It's far worse on AM. Authorizing a station on 1210AM in Michigan to operate at high power at night [0] would not only interfere with the Philadelphia station in Michigan - it would also cause interference in Pennsylvania.
[0] Actually, there's already a station operating on 1210 in Michigan. However, this station is not allowed to operate at night, when it could interfere with the Philadelphia outlet.
- The data rate and modem tones used are non-standard. (though public knowledge) One could build one's own encoder, but you won't do it easily with off-the-shelf parts.
- Stations are only required to forward EAN ("we're about to be nuked"), EAT ("OK, I guess we *aren't* going to get nuked"), and RMT. (monthly test) Many stations don't relay any other alert. (then again, many do)
- Stations are not required to automatically forward *anything*. They may hold even EAN/EAT/RMT for a few minutes, long enough to not relay if it's an obvious hoax. (then again, many stations *do* automatically forward everything)
- The larger the station, the less likely it will forward an alert without reviewing it for validity.
- Stations are required to monitor at least two sources of EAS data. To spoof a manned station, you'd need at least two transmitters.
Most programs are already archived. They have value (or at least, so the producers hope!) for later syndication (rerun) and/or sale on VHS/DVD.
Archiving of live broadcasts, such as newscasts, is a lot spottier. Most are recorded, but the tapes are reused after a week or so.
In the days before DVD recorders, storage costs were an issue. A few years worth of VHS tapes would easily fill a room. Then there's the need to dub all that material when the old recording format becomes obsolete... (many stations have archives of particularly historic material -- on 16mm film or 2" video tape -- and nothing that will play them...)
Even with DVD recorders, there's the issue of indexing - determining what's on which disk.
In fact many stations do record their programming. Probably more so that they can prove your commercial aired...
It could be a serious burden to smaller stations though. (you could comply with a cheap radio, three VHS machines in 8-hour mode, and a stack of tapes -- but that's a financial burden to a small standalone AM station...)
Canadian stations are already required to record their programming. Stations have been admonished (though I've never seen any more serious sanctions) for being unable to provide "logger tapes".
The USA Constitution prohibits the government from forcing one to provide evidence against oneself. I guess the justification here is that nobody is forced to take out a broadcasting license - and that available frequencies are scarce.
These two reasons are valid, but I think there's one more.
The cellular system depends on channel reuse. My phone call here in Cheatham County uses a particular channel - and other calls in Clarksville and downtown Nashville can use the same channel. Without interference, because my phone is running very low power and an antenna maybe 5 feet off the ground.
Bring that antenna 20,000 feet up in an airplane, and it becomes visible to a lot more base stations! (probably, every one in Middle Tennessee..) Now, "my" channel is unavailable for reuse over a very wide area.
One guy calling from an airplane isn't a big deal. A few hundred, and we run the risk of running out of channels.
Re:why ham radio isn't popular
on
Field Day 2004
·
· Score: 5, Insightful
That's long been a tension within the hobby. Are we about the medium, or about the message?
A large part of the hobby is about the medium. We really don't care what information is sent - we're interested in the method used to send that information.
Isn't that essentially the same motivation that drives kernel hackers? Who don't really care about what computing gets done, just that it can be done on a kernel they built themselves...
Re:Going the way of the dinosaurs
on
Field Day 2004
·
· Score: 2, Informative
(good luck!)
As the other post says, encryption is acceptable for authentication, but not for the message contents. Whether that addresses your concern is a good question(grin)...
The prohibitions on music and commercial traffic date back to the 1920s, and commercial stations' fear of competitions. Many of the earliest broadcast stations were hams transmitting music - once it became obvious broadcasting would be popular there was a fear that the ham bands would be filled with low-power broadcasters.
Commercial point-to-point radio using Morse Code existed at the time. In many foreign countries the commercial stations were operated by the government. (remember what they say about governments & competition(grin)!)
I think most hams haven't even thought about what the regulations do to the usability of ham radio for data communications. Removing the limits on commercial traffic altogether runs the risk of overwhelming experimental traffic with businesses looking for a cheap comms system. (I'd bet the common carriers wouldn't stand for it) You could safely come partway though.
We use the Chipcorder at work for our music-on-hold. It runs for months without attention. Jameco is one of many distributors of these chips.
They'll directly drive a speaker, though not very loud. (it'll work in a quiet place; you'll need an external amplifier if there's noise) There's very few parts needed besides the chip.
We had a lot of grief with this one last night. (I'm going to be rich next Friday, after seven hours of overtime. I'd rather have had seven hours of sleep.)
It seems to have some effects not attributed to Blaster - it appears to have flooded some of our own machines. (we're not windowsupdate.com!) For example, causing two SQL servers to reboot spontaneously at random intervals until we cut our connection to corporate HQ.
We then got to spend several hours trying to figure out how to get a couple of mission-critical applications working when they connect to outside vendors on "strange" ports - and corporate has decided to cut off any ports they're not familiar with. Thank God for saving obsolete satellite receivers and a few hundred feet of RS-232 cable.
A problem we had was proprietary applications whose vendors haven't qualified the patches. ----- As for home users not patching...
It's easy to belittle those who don't keep their systems patched to the latest revision. IIRC the appropriate patches for this one run to roughly 10MB. For dialup users, that's the better part of an hour of downloading. Often, tying up one's only phone for that period.
IMHO there are some fundamental structural issues in Windows. At least, it should NEVER be possible for software to be installed on a system without the user's consent. It should NEVER be possible to add items to the startup sequence without the user's consent. Sure, fixing that won't stop worms (there are plenty of users who say "Yes" to anything...) but it'd sure help.
...but in many more instances it was equipment manufacturers (especially Motorola and Ericsson) who convinced local agencies to buy complicated and failure-prone trunked radio systems. These systems were often (though not always) solutions in search of problems,...
(failure-prone: read this... It's by no means the only such incident...)
And, I might add, to a considerable degree the fault for the problem lies with these equipment manufacturers. They knew (or certainly should have!) that there would be commercial two-way communications in the channels adjacent to the public-safety channels, but they sold equipment that could be overloaded by such adjacent-channel operation.
Cell towers are relatively low-powered. If those adjacent channels had been assigned to regular two-way radio (or worse, for pagers), there would have been fewer transmitting sites but those sites would have been much more powerful.
=====
With regard to the transfer of the 700MHz band from television... Only four channels (24MHz) of this band are planned for transfer to public-safety communications. The rest will be auctioned for commercial use. I suppose the transfer of four 6MHz blocks, rather than various channels spread among the commercial users, will make 700MHz public-safety comms less susceptible to this kind of problem.
Of course, we (the taxpayers...) will have to buy another new set of equipment...
This unfortunately doesn't work to stop the postal spam. On the other hand, it does ensure that the spammer pays the cost of disposing of their garbage, not you. Your property taxes should pay for the disposal of the garbage you generate - let the spammers pay the taxes to dispose of their garbage.
I don't bother waiting for prepaid envelopes to show up - any garbage postal spammers dump in my mailbox immediately gets "RETURN TO SENDER" written on it & dumped back in the mailbox. You need to mark out your address and the bar code first, otherwise the USPS's automatic sorting equipment will return it to *you* instead of the sender.
When I *do* get prepaid envelopes though, I do use them. Often I'll get a bunch at once - one of the mass coupon mailings - use the prepaid envelopes & cards from some of the offenders to return the crap of the others.
Incidentially, as a demonstration of the (non-)value of voluntary opt-out lists... I'm signed up for the DMA's Mail Preference List and registered with all three credit bureaus as not allowing my address to be sold to marketers. I *still* get about a pound of junk mail a week. The credit-card solicitations have pretty much stopped but I had to directly write Capital One and one other issuer whose name I've forgotten to get to that point.
IMHO the credit bureaus owe me $1.85 (five stamps) but they've made it clear they have no intention of paying their bill...
Imagine that FEMA is unable to test their equipment or run practice/training drills when there's no emergency.
What are the chances there will be undiagnosed equipment problems? Operators who aren't familiar with the gear? Operators who aren't familiar with proper operating procedure? (locations where they can't hear anything because there's some other interference source that had been buried under the BPL noise?)
Alternatively, do you want to have a broadband provider that stops working for a few hours a week so FEMA can run drills? (then add in the Army, the FAA, the Navy, CIA,...)
Actually, frequency+10.7MHz. (and for AM, frequency+455KHz) That keeps down the range of frequencies the oscillator must tune across, as a percentage of the operating frequency. Which makes the oscillator easier to build.
Besides the jamming plans, you could foil such a system by using a different intermediate frequency, which would cause the oscillator to be on the "wrong" frequency for what the board expects. For example, with a 10.7MHz IF, when tuned to dance music station 102.5 The Party, my oscillator would be on 113.2MHz. If I changed the IF to 9.9MHz, my oscillator would be on 113.2 when I was listening to country station 103.3 KDF. Many car radios already use alternative intermediate frequencies for AM. (for different reasons)
It *is* possible to build a radio that doesn't use an oscillator at all. Many early (1920s) radios used such circuits. It's far more difficult to build a FM radio with such a circuit but it has been done.
Sometimes, you can hear other people's oscillators. Tune your car radio to a weak station that's 10.6 or 10.8MHz higher in frequency than a popular local station. Drive in heavy traffic. On occasion, your radio will go silent - the weak station is being swamped by the oscillator in a nearby car.
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The station I work for uses GPS time.
The programs start late on purpose.
(I guess if you're in management it makes sense.....)
I think you're confusing two concepts.
Each U.S. (and Canadian, and Mexican) TV station has been assigned a 6MHz chunk of spectrum for their analog signal. They can transmit a single program stream in this spectrum.
More recently, each station in these three countries has also been assigned a second 6MHz chunk for digital operation.
It is possible to transmit more than one program stream in this spectrum.
In the U.S., stations are required to transmit at least one standard-definition program stream in this spectrum. This is what KLEP (the station mentioned in the link) is saying they can't afford to do.
U.S. stations may optionally choose to transmit additional program streams. It's these optional additional streams cable has not been required to carry when they exist.
(I do believe the failure of the FCC to require carraige of the additional streams is a mistake that will make it difficult for many smaller stations to finance digital conversion)
I think the "indecency police" have gone too far, but I don't see any inconsistency in expecting satellite radio and broadcast radio to live by the same rules. (likewise cable and broadcast TV) With well over 80% of homes having cable or satellite, does it accomplish anything to keep Janet's nipple off CBS when it's perfectly legal to show it on MTV?
This spectrum was hardly free, and it's very much not true that stations aren't doing anything with the second channels.
The station I work for had to:
Not cheap. And we lucked out by drawing RF channel 10, meaning we could run 42 kilowatts of power as opposed to our competitors who need 1000 kilowatts to achieve the same coverage. I don't want to know about their electric utility bills!
This is an expense imposed on these stations. Even if your business plan doesn't have room for high-definition. Even if your business plan depends on multicasting. (multiple programs over the same transmitter -- the FCC has decided cable is not required to carry the additional programs, making multicasting economically impractical.)
The stations' other alternative: do nothing with their second channel, and know that at some future point, they will be forced to surrender their license and go out of business. (At least one station already has.(scroll down to "1993+"))
IMHO there is no shortage of available public-safety spectrum. The two-way radio manufacturers know that each time a new chunk of public-safety spectrum is opened, they'll sell thousands if not millions of new radios. The old 150MHz and 460MHz bands are being abandoned in droves - but are perfectly suited for public-safety work. (the old 40MHz band has been so fully abandoned that the FCC feels safe in allowing special temporary use for a FM broadcast station commemorating Armstrong's original FM experiments in New York City...)
That $190 figure is pretty close to accurate, for what the least-expensive set-top box is selling for in the States.
It seems some viewers are pretty sensitive to MPEG artifacts; others (me!) don't notice them unless they're serious. Personally I think the improvement in quality is indeed pretty dramatic, even on a standard-definition display.
The law already contains an "out". If less than 85% of homes are able to receive DTV programs, the deadline may be extended.
It's not entirely clear whether Congress meant for this 85% figure to include people who are watching digital programs on analog recievers after having them downconverted by their cable/satellite company. Some argue that it doesn't, in which case the 85% figure will likely never be met.
(even if cable/satellite subscribers are included, subscribership varies wildly from place to place with some cities having as much as 30% off-air viewership.)
Virtually nobody actually believes analog will shut down in 2006.Does this quote bother anyone else?:
" Hardy acknowledged, however, that the indices are not complete. "The FBI does not index every name in its files," Hardy told the court. Other than the subject, suspects and victims, names in FBI files are indexed at the discretion of the investigating agent and supervisors if they are "considered pertinent, relevant or essential for future retrieval." "
If a deficient index makes it impossible to answer FOIA requests from outside personnel... doesn't it also make it impossible to answer internal requests from the FBI's own agents? What happens if the investigating agent misjudges the relevance of a name to future investigations?
It may be possible to observe the radio effects of the meteor shower without being a ham or having an extensive station.
Regular FM radio and TV broadcasts are also reflected by the ionized trails.
Try tuning to an empty channel, as low on the dial as possible. Of course, for TV you'll need a set with a regular antenna, not cable or satellite. For FM, your car radio is probably the best radio you own for this purpose.
Sit there and listen/watch. You should see/hear brief bursts of signal. If you're really lucky, you'll hear something that will allow you to identify the station you saw/heard.
Might be something interesting to listen to while you're waiting for visible meteors -- or for the clouds to go away...
I have numerous passwords imposed from outside. Let's see:
Point is, many users don't have only one set of passwords to remember - they have many. Some at work, some at home.
Demanding regular changes to securely-chosen passwords is simply not humanly possible. If you were to steal my wallet, you'd find at least three of my passwords... (no, not my ATM PIN!)
(emphasis mine)
I guess that means if he decides to spam again, Massachusetts can reopen the case and seek more damages.
I wonder (not being a lawyer) whether a contempt citation and jail time would be an option if one were to repeatedly refuse to live up to a settlement?
Digital satellite and cable are considerably more compressed than most OTA digital TV.
That said, some people seem far more sensitive to MPEG artifacts than others. (just like some people think MP3s have unlistenable distortion, while others can't tell the difference from the uncompressed source)
Basically, television is being compressed into a smaller chunk of spectrum.
Under the old rules, TV used channels 2-69. When the digital conversion is complete, channels 52-69 will be removed from TV service. Four of those channels will be used for public safety; the rest will be auctioned.
I suppose on average, TV is being moved to *lower* frequencies. However, in many cases individual stations are moving *higher*. This is usually because when a new station is built, it prefers to use the lowest available channel. (oversimplification but reasonable) So, when time came to allocate second channels for digital, the channels that were most likely to be available were higher channels.
After analog is closed, stations will be allowed to move their digital operations to their current analog channels. The Nashville PBS station that currently operates on digital channel 46 will be allowed to move its digital operation to their current analog channel 8.
Higher frequencies penetrate buildings better, while lower ones cover a greater distance for a given amount of transmitter power. Lower frequencies also require larger antennas. (not good for, say, the handheld radio on a police officer's belt!)
Subchannels are a mixed blessing. Programming is VERY expensive to produce. In many cases it may be impossible to raise enough extra revenue by carrying two extra games to cover the cost of the rights to those games.
The area over which a radio transmission causes interference is far larger than the area over which it provides useful service. For example, according to the FCC, WSM-FM in Nashville provides service over a radius of 79km around their tower. WSM-FM would interfere with another station on the same frequency within 182km of the tower.
It's far worse on AM. Authorizing a station on 1210AM in Michigan to operate at high power at night [0] would not only interfere with the Philadelphia station in Michigan - it would also cause interference in Pennsylvania.
[0] Actually, there's already a station operating on 1210 in Michigan. However, this station is not allowed to operate at night, when it could interfere with the Philadelphia outlet.
- The data rate and modem tones used are non-standard. (though public knowledge) One could build one's own encoder, but you won't do it easily with off-the-shelf parts.
- Stations are only required to forward EAN ("we're about to be nuked"), EAT ("OK, I guess we *aren't* going to get nuked"), and RMT. (monthly test) Many stations don't relay any other alert. (then again, many do)
- Stations are not required to automatically forward *anything*. They may hold even EAN/EAT/RMT for a few minutes, long enough to not relay if it's an obvious hoax. (then again, many stations *do* automatically forward everything)
- The larger the station, the less likely it will forward an alert without reviewing it for validity.
- Stations are required to monitor at least two sources of EAS data. To spoof a manned station, you'd need at least two transmitters.
Most programs are already archived. They have value (or at least, so the producers hope!) for later syndication (rerun) and/or sale on VHS/DVD.
Archiving of live broadcasts, such as newscasts, is a lot spottier. Most are recorded, but the tapes are reused after a week or so.
In the days before DVD recorders, storage costs were an issue. A few years worth of VHS tapes would easily fill a room. Then there's the need to dub all that material when the old recording format becomes obsolete... (many stations have archives of particularly historic material -- on 16mm film or 2" video tape -- and nothing that will play them...)
Even with DVD recorders, there's the issue of indexing - determining what's on which disk.
In fact many stations do record their programming. Probably more so that they can prove your commercial aired...
It could be a serious burden to smaller stations though. (you could comply with a cheap radio, three VHS machines in 8-hour mode, and a stack of tapes -- but that's a financial burden to a small standalone AM station...)
Canadian stations are already required to record their programming. Stations have been admonished (though I've never seen any more serious sanctions) for being unable to provide "logger tapes".
The USA Constitution prohibits the government from forcing one to provide evidence against oneself. I guess the justification here is that nobody is forced to take out a broadcasting license - and that available frequencies are scarce.
These two reasons are valid, but I think there's one more.
The cellular system depends on channel reuse. My phone call here in Cheatham County uses a particular channel - and other calls in Clarksville and downtown Nashville can use the same channel. Without interference, because my phone is running very low power and an antenna maybe 5 feet off the ground.
Bring that antenna 20,000 feet up in an airplane, and it becomes visible to a lot more base stations! (probably, every one in Middle Tennessee..) Now, "my" channel is unavailable for reuse over a very wide area.
One guy calling from an airplane isn't a big deal. A few hundred, and we run the risk of running out of channels.
That's long been a tension within the hobby. Are we about the medium, or about the message?
A large part of the hobby is about the medium. We really don't care what information is sent - we're interested in the method used to send that information.
Isn't that essentially the same motivation that drives kernel hackers? Who don't really care about what computing gets done, just that it can be done on a kernel they built themselves...
(good luck!)
As the other post says, encryption is acceptable for authentication, but not for the message contents. Whether that addresses your concern is a good question(grin)...
The prohibitions on music and commercial traffic date back to the 1920s, and commercial stations' fear of competitions. Many of the earliest broadcast stations were hams transmitting music - once it became obvious broadcasting would be popular there was a fear that the ham bands would be filled with low-power broadcasters.
Commercial point-to-point radio using Morse Code existed at the time. In many foreign countries the commercial stations were operated by the government. (remember what they say about governments & competition(grin)!)
I think most hams haven't even thought about what the regulations do to the usability of ham radio for data communications. Removing the limits on commercial traffic altogether runs the risk of overwhelming experimental traffic with businesses looking for a cheap comms system. (I'd bet the common carriers wouldn't stand for it) You could safely come partway though.
We use the Chipcorder at work for our music-on-hold. It runs for months without attention. Jameco is one of many distributors of these chips.
They'll directly drive a speaker, though not very loud. (it'll work in a quiet place; you'll need an external amplifier if there's noise) There's very few parts needed besides the chip.
Yeah, thanks a whole lot...
We had a lot of grief with this one last night. (I'm going to be rich next Friday, after seven hours of overtime. I'd rather have had seven hours of sleep.)
It seems to have some effects not attributed to Blaster - it appears to have flooded some of our own machines. (we're not windowsupdate.com!) For example, causing two SQL servers to reboot spontaneously at random intervals until we cut our connection to corporate HQ.
We then got to spend several hours trying to figure out how to get a couple of mission-critical applications working when they connect to outside vendors on "strange" ports - and corporate has decided to cut off any ports they're not familiar with. Thank God for saving obsolete satellite receivers and a few hundred feet of RS-232 cable.
A problem we had was proprietary applications whose vendors haven't qualified the patches.
-----
As for home users not patching...
It's easy to belittle those who don't keep their systems patched to the latest revision. IIRC the appropriate patches for this one run to roughly 10MB. For dialup users, that's the better part of an hour of downloading. Often, tying up one's only phone for that period.
IMHO there are some fundamental structural issues in Windows. At least, it should NEVER be possible for software to be installed on a system without the user's consent. It should NEVER be possible to add items to the startup sequence without the user's consent. Sure, fixing that won't stop worms (there are plenty of users who say "Yes" to anything...) but it'd sure help.
(failure-prone: read this... It's by no means the only such incident...)
And, I might add, to a considerable degree the fault for the problem lies with these equipment manufacturers. They knew (or certainly should have!) that there would be commercial two-way communications in the channels adjacent to the public-safety channels, but they sold equipment that could be overloaded by such adjacent-channel operation.
Cell towers are relatively low-powered. If those adjacent channels had been assigned to regular two-way radio (or worse, for pagers), there would have been fewer transmitting sites but those sites would have been much more powerful.
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With regard to the transfer of the 700MHz band from television... Only four channels (24MHz) of this band are planned for transfer to public-safety communications. The rest will be auctioned for commercial use. I suppose the transfer of four 6MHz blocks, rather than various channels spread among the commercial users, will make 700MHz public-safety comms less susceptible to this kind of problem.
Of course, we (the taxpayers...) will have to buy another new set of equipment...
This unfortunately doesn't work to stop the postal spam. On the other hand, it does ensure that the spammer pays the cost of disposing of their garbage, not you. Your property taxes should pay for the disposal of the garbage you generate - let the spammers pay the taxes to dispose of their garbage.
I don't bother waiting for prepaid envelopes to show up - any garbage postal spammers dump in my mailbox immediately gets "RETURN TO SENDER" written on it & dumped back in the mailbox. You need to mark out your address and the bar code first, otherwise the USPS's automatic sorting equipment will return it to *you* instead of the sender.
When I *do* get prepaid envelopes though, I do use them. Often I'll get a bunch at once - one of the mass coupon mailings - use the prepaid envelopes & cards from some of the offenders to return the crap of the others.
Incidentially, as a demonstration of the (non-)value of voluntary opt-out lists... I'm signed up for the DMA's Mail Preference List and registered with all three credit bureaus as not allowing my address to be sold to marketers. I *still* get about a pound of junk mail a week. The credit-card solicitations have pretty much stopped but I had to directly write Capital One and one other issuer whose name I've forgotten to get to that point.
IMHO the credit bureaus owe me $1.85 (five stamps) but they've made it clear they have no intention of paying their bill...
"The spasm of activity is aimed at attracting voluntary subscribers to the lawmakers' e-mail lists, "
Voluntary, my *ss...
After writing my representatives via email a few months back, one of my Senators (Lamar Alexander (TN)) saw fit to add me to his mailing list.
I guess if you choose to express your opinion on the issues, you're opting in to be spammed.
One might add, this doesn't apply only to hams.
Imagine that FEMA is unable to test their equipment or run practice/training drills when there's no emergency.
What are the chances there will be undiagnosed equipment problems? Operators who aren't familiar with the gear? Operators who aren't familiar with proper operating procedure? (locations where they can't hear anything because there's some other interference source that had been buried under the BPL noise?)
Alternatively, do you want to have a broadband provider that stops working for a few hours a week so FEMA can run drills? (then add in the Army, the FAA, the Navy, CIA,...)
Actually, frequency+10.7MHz. (and for AM, frequency+455KHz) That keeps down the range of frequencies the oscillator must tune across, as a percentage of the operating frequency. Which makes the oscillator easier to build.
Besides the jamming plans, you could foil such a system by using a different intermediate frequency, which would cause the oscillator to be on the "wrong" frequency for what the board expects. For example, with a 10.7MHz IF, when tuned to dance music station 102.5 The Party, my oscillator would be on 113.2MHz. If I changed the IF to 9.9MHz, my oscillator would be on 113.2 when I was listening to country station 103.3 KDF. Many car radios already use alternative intermediate frequencies for AM. (for different reasons)
It *is* possible to build a radio that doesn't use an oscillator at all. Many early (1920s) radios used such circuits. It's far more difficult to build a FM radio with such a circuit but it has been done.
Sometimes, you can hear other people's oscillators. Tune your car radio to a weak station that's 10.6 or 10.8MHz higher in frequency than a popular local station. Drive in heavy traffic. On occasion, your radio will go silent - the weak station is being swamped by the oscillator in a nearby car.