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PDXPLT
join:2003-12-04
Banks, OR | reply to rf_engineer
Re: No "Distant TV" and "Service Contour" have specific defintions in FCC Rules, with both regulatory and technical implications.
Every broadcast station has a specific coverage area in which they are assigned to operate. "Distant TV" are stations whose coverage area is outside the receiver's location. Under the FCC OTARD Rule, your Homeonwers' Association or landlord can't prevent you from installing a TV antenna to receive local TV, but they can prevent you from installing one exclusively for receiving distant TV. The SHVA Act allows satellite providers to rebroadcast local TV, but not Distant TV.
Technical rules for TV are contained in Part 73. Each TV station has a "Service Contour" defined, a rough approximation of its coverage area. It's determined by transmitter EIRP, TX antenna directionality and HAAT, assumed receive antenna height (30 ft), receive antenna gain (different for VHF-low, VHF-high, and UHF), assumed receiver noise figure, reguired received SNR (e.g., 15 dB for DTV), and propagation curves in Part 73. For analog TV, there were actually two contours, Grade A and Grade B. Grade A required a higher SNR had resulted in a better pciture, but the coverage area extended out to the Grade B contour.
Within the Service Contour, the Longley-Rice propagation model is applied to account for detailed geographic features, and to arrive at the actual coverage area. Locations within the coverage area are considered "served" by that station. Interference from other sources are not permitted. A DBS provider may not provide a distant network feed into that area. A good engineering introduction into these calculations can be found on the FCC Office of Engineering Technology website in document OET69, "Longley-Rice Methodology for Evaluating TV Coverage and Interference", if you want all the gory details. 
Locations outside the coverage area are considered "unserved" by the TV station. Any interference from an unlicensed device would not be considered harmful interference under Part 15. You can't "seriously degrade, obstruct, or interrupt" a radiocommunications service, if the interruption occurs outside the service's licensed service area. | |
| said by PDXPLT: Under the FCC OTARD Rule, your Homeonwers' Association or landlord can't prevent you from installing a TV antenna to receive local TV, but they can prevent you from installing one exclusively for receiving distant TV. Where's the language supporting this? I don't see it, skimming 47CFR1.4000.
Locations outside the coverage area are considered "unserved" by the TV station. Any interference from an unlicensed device would not be considered harmful interference under Part 15. You can't "seriously degrade, obstruct, or interrupt" a radiocommunications service, if the interruption occurs outside the service's licensed service area.
Locations outside the coverage area are considered unserved, but only for the purposes of determining interference from other licensees. I don't think the service contours are applicable in regards to Part 15.
I skimmed over Part 73; looking at 73.612 they don't provide protection from other Part 73 licensed stations:
Permittees and licensees of TV broadcast stations are not protected from any interference which may be caused by the grant of a new station or of authority to modify the facilities of an existing station in accordance with the provisions of this subpart
Part 15 is a different animal and can't interfere regardless. I don't think the service contours are applicable to Part 15 harmful interference. Part 15 doesn't define a radiocommunications service as being limited to just its contour area, it merely says it can't harmfully interfere with a radiocommunications service. Of course the FCC could get loopy and play with the meaning of "harmful" (like they did with BPL). | |
| reply to rf_engineer
it doesn't matter if i post my callsign or not.you still would not know it was mine.I dont have to prove anything to anyone especially anyone on a stupid forum board that doesn't mean anything
as for the testing on hf.I saw all of it,and didn't see test done in the same areas before bbl was up and running just after.which didn't tell me anything as you know interference can come from many different things | |
1 edit | said by pissed :
it doesn't matter if i post my callsign or not.you still would not know it was mine.I dont have to prove anything to anyone especially anyone on a stupid forum board that doesn't mean anything Quite true. Even if you did post a callsign, you've shown with your posts that you're not very experienced as an amateur.
as for the testing on hf.I saw all of it,and didn't see test done in the same areas before bbl was up and running just after.which didn't tell me anything as you know interference can come from many different things
This is the "HF interference can come from many things" defense and was used several times by utilities and debunked (the most notable was from a utility in PA that claimed neon signs made the interference....in a residential neighborhood). Somehow it was just coincidence that all the OFDM-based BPL systems had carriers neatly spaced 1.2 kHz apart all over the HF bands, and spread-spectrum based BPL systems happened to have hash all over the HF bands and the signal levels increased near BPL feedpoints. It's all documented (read the numerous FCC NPRM and NOI filings) and you're bit late with your capitalization-challenged revisionist claims. | | |
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PDXPLT
join:2003-12-04
Banks, OR | reply to rf_engineer
said by rf_engineer:said by PDXPLT: Under the FCC OTARD Rule, your Homeonwers' Association or landlord can't prevent you from installing a TV antenna to receive local TV, but they can prevent you from installing one exclusively for receiving distant TV. Where's the language supporting this? I don't see it, skimming 47CFR1.4000. See »www.fcc.gov/mb/facts/otard.html
Locations outside the coverage area are considered "unserved" by the TV station. Any interference from an unlicensed device would not be considered harmful interference under Part 15. You can't "seriously degrade, obstruct, or interrupt" a radiocommunications service, if the interruption occurs outside the service's licensed service area.
Locations outside the coverage area are considered unserved, but only for the purposes of determining interference from other licensees. I don't think the service contours are applicable in regards to Part 15.
I skimmed over Part 73; looking at 73.612 they don't provide protection from other Part 73 licensed stations:
Permittees and licensees of TV broadcast stations are not protected from any interference which may be caused by the grant of a new station or of authority to modify the facilities of an existing station in accordance with the provisions of this subpart
Part 15 is a different animal and can't interfere regardless. No where in Part 15 does it state that Part 15 devices may not interfere with licensed stations. Unfortunately this seems to be a common misbelief among Hams. Hams that live and breath regulatory stuff like Ed Hare of ARRL get this right, but the rank and file often does not.
Part 15 explicitly says that the interference may not rise to the level of "harmful interference". It does not say that there must be no interference whatsoever. Harmful interference, in the case of a broadcast station, is that which "seriously degrade, obstruct, or interrupt" a service, which you can't do if the interruption is outside the service area. There's no ambiguity in this: go read the FCC White Space NPRM. The requires are all defined around protecting station operation within its coverage area If you're saying that no unlicensed device can ever interfere with any reception of any licensed signal, anywhere, under any circumstances, you're making up new law. We'll have to outlaw flourescent light bulbs, brush motors, and lots of other things. | |
PDXPLT
join:2003-12-04
Banks, OR | reply to MrMoody
It appears you are unfamilar with the White Space NPRM, Part 15, Part 73, and Part 74.
said by MrMoody:Does matter. When I say 'distant' I don't mean out of contour, I mean any station over about 25 miles away, and there are plenty of contours which go a lot farther than that. As I explianed below, "distant TV" and "Service Contour" have specific meanings when talking about FCC Rules.
All those unlicensed devices you name (legal and illegal) are operating at very low power with a range measured in feet, and are subject to Part 15 rules; if someone complains you must correct the interference or stop using the device. So would the white space devices. The NPRM proposes that that be defined in Part 15.244. The "personal/portable" class of devices (the one the NAB claims they're the most worried about), would operate at the same low power levels as the other Part 15 devices you refer to.
Most so-called "UHF" devices, including remotes and portable phones, are in the used-for-little-else 902-928 MHz amateur band, or many older ones (pre 1990 or so) were in the 450-470 MHz shared commercial band. The highest UHF TV channel is 801 MHz (693 MHz after Feb.) and the lowest is 471 MHz. These devices don't interfere with TV because they are outside the TV band. This is not correct; you're combining several different classes of Part 15 devices. Cordless phones operate under 15.233 in the ~48 MHz band, and under 15.247 in the 902-928, 2.4 GHz, and 5 GHz ISM bands. In contrast, UHF remotes operate under 15.231, at 40 MHz, and any frequency above 70 MHz (only brief pushbutton remotes; e.g., RC toys aren't permitted).
Wireless microphones (the high end ones requiring licensing) aren't generally being operated for any amount of time in residential areas either. walk into any music store, or any online muscian supply website, and almost all of wireless microphones for sale operate in the TV bands. They are what is used by the kids in the garage band next door, in the church down the street, and in the grade school auditorium.
Show me one device, in common household use, outside of license-required microphones, that operates in the UHF TV bands of 470-608 & 614-806 MHz, which IS EXACTLY where the white space boxes will be (up to the new end at 698 MHz anyway). No guessing, show the frequency. Analog TVs are VERY sensitive to this sort of thing, so these bands weren't used for this sort of thing.
GO read the FCC white space NPRM document, where it states that unlicensed remotes, and medical telemetry equipment, are already operating in the TV bands. | |
| reply to PDXPLT
said by PDXPLT:said by rf_engineer:said by PDXPLT: Under the FCC OTARD Rule, your Homeonwers' Association or landlord can't prevent you from installing a TV antenna to receive local TV, but they can prevent you from installing one exclusively for receiving distant TV. Where's the language supporting this? I don't see it, skimming 47CFR1.4000. See » www.fcc.gov/mb/facts/otard.html That's an FAQ. They mention "local TV", however there's no definition of local that I can see. In any case 47CFR1.4000 is authoritative, not an FAQ. There's no language there supporting this, that I can find.
Locations outside the coverage area are considered "unserved" by the TV station. Any interference from an unlicensed device would not be considered harmful interference under Part 15. You can't "seriously degrade, obstruct, or interrupt" a radiocommunications service, if the interruption occurs outside the service's licensed service area.
Locations outside the coverage area are considered unserved, but only for the purposes of determining interference from other licensees. I don't think the service contours are applicable in regards to Part 15. This is alien concept for Hams, since their hobby is not a broadcast service. the whole point of DX'ing is to receive distant stations, and their licenses entitle them to operate anywhere, even internationally with appropriate reciprocal agreements. In contrast, a broadcast license gives a station use of the spectrum over only a certain geographic area. Outside that area, the spectrum is allocated for other users as the FCC/NTIA sees fit. | |
 MrMoodyFree range slavePremium
join:2002-09-03
Smithfield, NC
1 edit | reply to PDXPLT
said by PDXPLT:walk into any music store, or any online muscian supply website, and almost all of wireless microphones for sale operate in the TV bands. They are what is used by the kids in the garage band next door, in the church down the street, and in the grade school auditorium. All illegal, unprotected and unlicenseable uses. You sound like you work for someone who will benefit from this. These are $500+ professional items, garage kids are unlikely to have them when much cheaper alternatives are available.
Also, they can be set to a channel known to the user to be unused in the area. This worked until DTV came along; now the average Joe doesn't know what channels are used any more, and a LOT more are used. No doubt there are a few out there with an incorrect channel choice causing problematic interference for a few nearby DTV users, who have no clue where it's coming from.
GO read the FCC white space NPRM document, where it states that unlicensed remotes, and medical telemetry equipment, are already operating in the TV bands.
I knew this couldn't be right so I researched it. A TV remote operating in the UHF-TV band would make visible effects on a rabbit-ear TV in the same room. The analog TV picture signal has virtually no immunity to stray signals. Even if it was permitted, no manufacturer in their right mind would do this.
They wouldn't lie or make a mistake in an NPRM would they?
quote:
PART 15_RADIO FREQUENCY DEVICES
Subpart C_Intentional Radiators
Sec. 15.242 Operation in the bands 174-216 MHz and 470-668 MHz.
(a) The marketing and operation of intentional radiators under the provisions of this section is restricted to biomedical telemetry devices employed solely on the premises of health care facilities.
No part 15 intentional radiators are allowed to operate in the TV bands except medical telemetry.
I'm telling you, there are NO CONSUMER REMOTES that operate in the UHF TV bands. Every one I could find specs on works in the amateur 420-450 MHz band. Find one that does, or quote the rule that allows the exception to the above.
So that leaves expensive microphones, which I've covered, and medical telemetry.
Medical telemetry is even more rare than the pro wireless microphones AND they are no longer a part 15 device but a part 95 device with their own allocated bands, and new medical devices using the TV bands under part 15 have not been approved since 2002. Even your holy NPRM (i.e. glorified sales presentation) refers to this.
quote:
PART 15_RADIO FREQUENCY DEVICES
Subpart A_General
Sec. 15.37 Transition provisions for compliance with the rules.
Equipment may be authorized, manufactured and imported under the rules in effect prior to June 23, 1989, in accordance with the following schedules:
(a) For all intentional and unintentional radiators, except for receivers: Radio frequency equipment verified by the responsible party or for which an application for a grant of equipment authorization is submitted to the Commission on or after June 23, 1992, shall comply with the regulations specified in this part. Radio frequency equipment that is manufactured or imported on or after June 23, 1994, shall comply with the regulations specified in this part.
(i) Effective October 16, 2002, an equipment approval may no longer be obtained for medical telemetry equipment operating under the provisions of Sec. 15.241 or Sec. 15.242 [operation in the TV bands]. The requirements for
obtaining an approval for medical telemetry equipment after this date are found in Subpart H of Part 95 of this chapter.
All that said, I did see where one of the proposals is to use a "beacon" system where the allowable frequencies for the area are broadcast from a beacon transmitter. This could work acceptably IF the beacons' data is maintained properly AND the devices CANNOT be made to transmit without receiving the beacon. This would result in the devices being inoperable in certain places, and might make working ones become inoperable later if their channels get licensed away.
However, again, this is not going to be the magic broadband for everyone no matter what they promise, for obvious reasons I've already explained.
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Electile Dysfunction: the inability to become aroused over the choice for President put forth by either party. | |
| reply to rf_engineer
I don't know much about it,but I do have friends that use UHF and vhf ham repeaters,and all i have seen them do is talk BS to each other,and occasionally talk about the weather,and half of them don't even know what the hell they are talking about.
I can get better information of the weather channel.I also understand hf is used for long distance so tell me what good is ham radio.IM my opinion every American deserves affordable broadband more than we need amateur radio,also not one fire,police,or EMS departments use ham radio they have their own repeaters | |
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