F
FloridaBear1776
Guest
If they used a lower bitrate, and introduced more redundancy, would the signal be more resistant to nighttime interference?
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HD on AM -- would a lower bitrate be more robust at night?
W
westlife
Guest
> If they used a lower bitrate, and introduced more
> redundancy, would the signal be more resistant to nighttime
> interference?
It would, but you're just treating the symptoms, not curing the problem. The better solution would be to eliminate the interference -- which, with the current hybrid IBOC design, can only be done by simply not transmitting IBOC at night, because IBOC causes more interference in the transmitter than it is designed to eliminate in the receiver.
A crude analogy to this would be deaths and injuries caused by careless and inattentive drivers (up to and including drunken driving). One approach to treat this problem would be to make cars bigger, heavier, and safer, so that when an idiot hits you, you're less likely to die or be seriously injured. But another approach would be to make all drivers better-educated, more skilled, and less likely to drive while impaired, so that these collisions are avoided in the first place. Which would you prefer?<P ID="signature">______________
It's a common mistake to not use punctuation in its proper form.
<a target="_blank" href=http://www.cgl.uwaterloo.ca/~csk/its.html>Be kind to your friend, the apostrophe.</a></P>
> redundancy, would the signal be more resistant to nighttime
> interference?
It would, but you're just treating the symptoms, not curing the problem. The better solution would be to eliminate the interference -- which, with the current hybrid IBOC design, can only be done by simply not transmitting IBOC at night, because IBOC causes more interference in the transmitter than it is designed to eliminate in the receiver.
A crude analogy to this would be deaths and injuries caused by careless and inattentive drivers (up to and including drunken driving). One approach to treat this problem would be to make cars bigger, heavier, and safer, so that when an idiot hits you, you're less likely to die or be seriously injured. But another approach would be to make all drivers better-educated, more skilled, and less likely to drive while impaired, so that these collisions are avoided in the first place. Which would you prefer?<P ID="signature">______________
It's a common mistake to not use punctuation in its proper form.
<a target="_blank" href=http://www.cgl.uwaterloo.ca/~csk/its.html>Be kind to your friend, the apostrophe.</a></P>
J
JasonW
Guest
> If they used a lower bitrate, and introduced more
> redundancy, would the signal be more resistant to nighttime
> interference?
In theory that should work. It's analogous to speaking slowly when trying to talk to someone across a noisy room, to ensure that you will be understood.
That is why deep space probes transmit back their data and pictures at low (by terrestrial data transfer standards) bit rates. This allows them to use smaller antennas and lower power transmitters, which reduces the spacecrafts' size and launch weight.
The difference is that unlike digital radio, the spacecraft mission controllers aren't trying to see the images or read the data "live" in real time--they can receive a single picture over hours if need be, collecting the data packets like so many raindrops. HD and DRM digital radio are "near-live," so there is a limit to how low the bit rate can go before it stops working well. If a 20 - 30 second delay would be acceptable (for music programming that shouldn't be an insurmountable problem), quite low bit rates should work. -- Jason
> redundancy, would the signal be more resistant to nighttime
> interference?
In theory that should work. It's analogous to speaking slowly when trying to talk to someone across a noisy room, to ensure that you will be understood.
That is why deep space probes transmit back their data and pictures at low (by terrestrial data transfer standards) bit rates. This allows them to use smaller antennas and lower power transmitters, which reduces the spacecrafts' size and launch weight.
The difference is that unlike digital radio, the spacecraft mission controllers aren't trying to see the images or read the data "live" in real time--they can receive a single picture over hours if need be, collecting the data packets like so many raindrops. HD and DRM digital radio are "near-live," so there is a limit to how low the bit rate can go before it stops working well. If a 20 - 30 second delay would be acceptable (for music programming that shouldn't be an insurmountable problem), quite low bit rates should work. -- Jason
J
JasonW
Guest
Mandating RF emission limits for electronic devices would also help reduce interference (and would help save energy as well).
Germany has such RF emission restrictions for TV sets, computers, dimmer switches, and microwave ovens, and the Long Wave and Medium Wave (AM) bands are relatively noise-free there. -- Jason
> > If they used a lower bitrate, and introduced more
> > redundancy, would the signal be more resistant to
> nighttime
> > interference?
>
> It would, but you're just treating the symptoms, not curing
> the problem. The better solution would be to eliminate the
> interference -- which, with the current hybrid IBOC design,
> can only be done by simply not transmitting IBOC at night,
> because IBOC causes more interference in the transmitter
> than it is designed to eliminate in the receiver.
>
> A crude analogy to this would be deaths and injuries caused
> by careless and inattentive drivers (up to and including
> drunken driving). One approach to treat this problem would
> be to make cars bigger, heavier, and safer, so that when an
> idiot hits you, you're less likely to die or be seriously
> injured. But another approach would be to make all drivers
> better-educated, more skilled, and less likely to drive
> while impaired, so that these collisions are avoided in the
> first place. Which would you prefer?
>
Germany has such RF emission restrictions for TV sets, computers, dimmer switches, and microwave ovens, and the Long Wave and Medium Wave (AM) bands are relatively noise-free there. -- Jason
> > If they used a lower bitrate, and introduced more
> > redundancy, would the signal be more resistant to
> nighttime
> > interference?
>
> It would, but you're just treating the symptoms, not curing
> the problem. The better solution would be to eliminate the
> interference -- which, with the current hybrid IBOC design,
> can only be done by simply not transmitting IBOC at night,
> because IBOC causes more interference in the transmitter
> than it is designed to eliminate in the receiver.
>
> A crude analogy to this would be deaths and injuries caused
> by careless and inattentive drivers (up to and including
> drunken driving). One approach to treat this problem would
> be to make cars bigger, heavier, and safer, so that when an
> idiot hits you, you're less likely to die or be seriously
> injured. But another approach would be to make all drivers
> better-educated, more skilled, and less likely to drive
> while impaired, so that these collisions are avoided in the
> first place. Which would you prefer?
>
> Mandating RF emission limits for electronic devices would
> also help reduce interference (and would help save energy as
> well).
>
> Germany has such RF emission restrictions for TV sets,
> computers, dimmer switches, and microwave ovens, and the
> Long Wave and Medium Wave (AM) bands are relatively
> noise-free there.
If the electric utilities would clean and inspect their lines and insulators on a regular basis, the noise levels would steeply drop in the US. That alone would help AM radio.
> also help reduce interference (and would help save energy as
> well).
>
> Germany has such RF emission restrictions for TV sets,
> computers, dimmer switches, and microwave ovens, and the
> Long Wave and Medium Wave (AM) bands are relatively
> noise-free there.
If the electric utilities would clean and inspect their lines and insulators on a regular basis, the noise levels would steeply drop in the US. That alone would help AM radio.
J
JasonW
Guest
> If the electric utilities would clean and inspect their
> lines and insulators on a regular basis, the noise levels
> would steeply drop in the US. That alone would help AM
> radio.
Good point. The manager of WNWS 790 almost went crazy because of an intermittent sizzling noise he could hear on his car radio within 1/4 mile of the station.
After engaging in much detective work with his engineer, they finally found the culprit--a cracked insulator on a utility pole. -- Jason
> lines and insulators on a regular basis, the noise levels
> would steeply drop in the US. That alone would help AM
> radio.
Good point. The manager of WNWS 790 almost went crazy because of an intermittent sizzling noise he could hear on his car radio within 1/4 mile of the station.
After engaging in much detective work with his engineer, they finally found the culprit--a cracked insulator on a utility pole. -- Jason
I have heard that if the electric utility wont fix a leaky insulator, then you can force the issue with a well placed shot from a .22 long rifle slug. Works all the time.... Names have been changed to protect the guilty
> > If the electric utilities would clean and inspect their
> > lines and insulators on a regular basis, the noise levels
> > would steeply drop in the US. That alone would help AM
> > radio.
>
> Good point. The manager of WNWS 790 almost went crazy
> because of an intermittent sizzling noise he could hear on
> his car radio within 1/4 mile of the station.
>
> After engaging in much detective work with his engineer,
> they finally found the culprit--a cracked insulator on a
> utility pole. -- Jason
>
> > If the electric utilities would clean and inspect their
> > lines and insulators on a regular basis, the noise levels
> > would steeply drop in the US. That alone would help AM
> > radio.
>
> Good point. The manager of WNWS 790 almost went crazy
> because of an intermittent sizzling noise he could hear on
> his car radio within 1/4 mile of the station.
>
> After engaging in much detective work with his engineer,
> they finally found the culprit--a cracked insulator on a
> utility pole. -- Jason
>
>
> Good point. The manager of WNWS 790 almost went crazy
> because of an intermittent sizzling noise he could hear on
> his car radio within 1/4 mile of the station.
>
> After engaging in much detective work with his engineer,
> they finally found the culprit--a cracked insulator on a
> utility pole. -- Jason
>
There is utility pole near my home that wipes out the
entire AM band for about 2 blocks...I have tried since 1983...
that's right...23 years...to get the electric company to
fix it. One service crew told me they would charge me a
$500 service call if I didn't stop bothering them...and added
"why would anyone want to listen to AM radio, anyway?"
> Good point. The manager of WNWS 790 almost went crazy
> because of an intermittent sizzling noise he could hear on
> his car radio within 1/4 mile of the station.
>
> After engaging in much detective work with his engineer,
> they finally found the culprit--a cracked insulator on a
> utility pole. -- Jason
>
There is utility pole near my home that wipes out the
entire AM band for about 2 blocks...I have tried since 1983...
that's right...23 years...to get the electric company to
fix it. One service crew told me they would charge me a
$500 service call if I didn't stop bothering them...and added
"why would anyone want to listen to AM radio, anyway?"
J
JasonW
Guest
> There is utility pole near my home that wipes out the
> entire AM band for about 2 blocks...I have tried since
> 1983...
> that's right...23 years...to get the electric company to
> fix it. One service crew told me they would charge me a
> $500 service call if I didn't stop bothering them...and
> added
> "why would anyone want to listen to AM radio, anyway?"
There are two solutions to this problem. Get a C. Crane Company "Justice Twin-Coil Ferrite Static Killer" AM radio antenna (it can be either directly connected or inductively coupled to *any* AM radio), or...do some backyard "plinking" on the offending utility pole insulator(s) with .22 shorts.
-- Jason
> entire AM band for about 2 blocks...I have tried since
> 1983...
> that's right...23 years...to get the electric company to
> fix it. One service crew told me they would charge me a
> $500 service call if I didn't stop bothering them...and
> added
> "why would anyone want to listen to AM radio, anyway?"
There are two solutions to this problem. Get a C. Crane Company "Justice Twin-Coil Ferrite Static Killer" AM radio antenna (it can be either directly connected or inductively coupled to *any* AM radio), or...do some backyard "plinking" on the offending utility pole insulator(s) with .22 shorts.
-- Jason> > Good point. The manager of WNWS 790 almost went crazy
> > because of an intermittent sizzling noise he could hear on
>
> > his car radio within 1/4 mile of the station.
> >
> > After engaging in much detective work with his engineer,
> > they finally found the culprit--a cracked insulator on a
> > utility pole. -- Jason
>
> There is utility pole near my home that wipes out the
> entire AM band for about 2 blocks...I have tried since
> 1983...
> that's right...23 years...to get the electric company to
> fix it. One service crew told me they would charge me a
> $500 service call if I didn't stop bothering them...and
> added
> "why would anyone want to listen to AM radio, anyway?"
You should tell your utility company that they are required to repair RF interference problems which their equipment and/or wiring is causing and that not only are you NOT going to pay the $500 for their service call to THEIR utility pole but if they don't do something about this immediately you intend to file a complaint with your state's Public Utilities Commission that it has taken 23 years of your reporting this problem for them to do absolutely nothing about it.
Utility companies generally HATE being scrutinized because of a complaint submitted to the "PUC" and often the threat of doing that will bring at least a serious visit by the utility company to the problem site. If necessary, tell them you will meet them at the pole and demonstrate the problem.
Either way... if the problem is being reported, they are required to fix it.
Cal
> > because of an intermittent sizzling noise he could hear on
>
> > his car radio within 1/4 mile of the station.
> >
> > After engaging in much detective work with his engineer,
> > they finally found the culprit--a cracked insulator on a
> > utility pole. -- Jason
>
> There is utility pole near my home that wipes out the
> entire AM band for about 2 blocks...I have tried since
> 1983...
> that's right...23 years...to get the electric company to
> fix it. One service crew told me they would charge me a
> $500 service call if I didn't stop bothering them...and
> added
> "why would anyone want to listen to AM radio, anyway?"
You should tell your utility company that they are required to repair RF interference problems which their equipment and/or wiring is causing and that not only are you NOT going to pay the $500 for their service call to THEIR utility pole but if they don't do something about this immediately you intend to file a complaint with your state's Public Utilities Commission that it has taken 23 years of your reporting this problem for them to do absolutely nothing about it.
Utility companies generally HATE being scrutinized because of a complaint submitted to the "PUC" and often the threat of doing that will bring at least a serious visit by the utility company to the problem site. If necessary, tell them you will meet them at the pole and demonstrate the problem.
Either way... if the problem is being reported, they are required to fix it.
Cal
> There is utility pole near my home that wipes out the
> entire AM band for about 2 blocks...I have tried since
> 1983...
> that's right...23 years...to get the electric company to
> fix it. One service crew told me they would charge me a
> $500 service call if I didn't stop bothering them...and
> added
> "why would anyone want to listen to AM radio, anyway?"
The FCC occasionally fines utility companies that fail to cooperate in repairing noise problems that affect radio amateurs.
I would consider:
- Go to http://www.v-soft.com/ZipSignal/zip_answer.asp , put in your ZIP code, and find the strongest AM station at your location that's affected by this interference.
- Write a concise letter (try to keep it down to a single page) explaining that electrical noise is interfering with WSM (or whatever your strongest AM signal is) , why you believe a utility pole is involved, and that you've received no cooperation from the utility in getting the problem resolved. Avoid anger or threats. (the threat is implied in the next step<grin>!)
- Send copies to:
the utility company
the AM station in question
your state's public service commission
the closest FCC office
Be sure the letter itself lists the addressees - you want the utility
company to *know* that the FCC and PSC are reading this.
I can't vouch for every state or utility company. However, I've found that the Tennessee Regulatory Authority *WILL* act, and promptly, on citizen complaints - and telephone companies, at least, *WILL* snap to attention when they hear from the TRA.
Oh, do you live within, say, 10-15 miles of your city's TV towers? Is over-the-air TV reception affected by this noise? (lower channels are more likely to be affected) If so, you might mention as much.
> entire AM band for about 2 blocks...I have tried since
> 1983...
> that's right...23 years...to get the electric company to
> fix it. One service crew told me they would charge me a
> $500 service call if I didn't stop bothering them...and
> added
> "why would anyone want to listen to AM radio, anyway?"
The FCC occasionally fines utility companies that fail to cooperate in repairing noise problems that affect radio amateurs.
I would consider:
- Go to http://www.v-soft.com/ZipSignal/zip_answer.asp , put in your ZIP code, and find the strongest AM station at your location that's affected by this interference.
- Write a concise letter (try to keep it down to a single page) explaining that electrical noise is interfering with WSM (or whatever your strongest AM signal is) , why you believe a utility pole is involved, and that you've received no cooperation from the utility in getting the problem resolved. Avoid anger or threats. (the threat is implied in the next step<grin>!)
- Send copies to:
the utility company
the AM station in question
your state's public service commission
the closest FCC office
Be sure the letter itself lists the addressees - you want the utility
company to *know* that the FCC and PSC are reading this.
I can't vouch for every state or utility company. However, I've found that the Tennessee Regulatory Authority *WILL* act, and promptly, on citizen complaints - and telephone companies, at least, *WILL* snap to attention when they hear from the TRA.
Oh, do you live within, say, 10-15 miles of your city's TV towers? Is over-the-air TV reception affected by this noise? (lower channels are more likely to be affected) If so, you might mention as much.
- Status