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Log-Periodic Antenna Design
Jim Lux wrote:
Cecil Moore wrote: http://ieeexplore.ieee.org/Xplore/lo...number=1610336 If you are a member of IEEE, you can access this paper: Multiband behavior of wideband Sierpinski fractal bow-tie antenna Yamini, A.H.; Soleimani, M. Microwave Conference, 2005 European Volume 3, Issue , 4-6 Oct. 2005 Page(s): 4 pp. - Digital Object Identifier 10.1109/EUMC.2005.1610336 interesting paper.. The big benefit (from a cursory reading).. is that you have a more consistent antenna pattern over the frequency range, which the vanilla bowtie does not. And a somewhat wider match bandwidth. (mostly extending it to higher frequencies) There is apparently a "big benefit" for some applications contrary to the nay-sayers on this newsgroup. Apparently, the self-symmetry of fractals leads to some predictability as far as wide-band response goes. Nothing magic, though. Don't remember anyone saying that fractals were magic. They certainly obey Maxwell's laws. I suspect their advantages, like their straight-wire cousins, lie in the predictability of their mathematical models. -- 73, Cecil http://www.w5dxp.com |
Log-Periodic Antenna Design
Cecil Moore wrote:
Jim Lux wrote: Cecil Moore wrote: http://ieeexplore.ieee.org/Xplore/lo...number=1610336 If you are a member of IEEE, you can access this paper: Multiband behavior of wideband Sierpinski fractal bow-tie antenna Yamini, A.H.; Soleimani, M. Microwave Conference, 2005 European Volume 3, Issue , 4-6 Oct. 2005 Page(s): 4 pp. - Digital Object Identifier 10.1109/EUMC.2005.1610336 interesting paper.. The big benefit (from a cursory reading).. is that you have a more consistent antenna pattern over the frequency range, which the vanilla bowtie does not. And a somewhat wider match bandwidth. (mostly extending it to higher frequencies) There is apparently a "big benefit" for some applications contrary to the nay-sayers on this newsgroup. Apparently, the self-symmetry of fractals leads to some predictability as far as wide-band response goes. As opposed to randomly trying other shapes, I guess.. So fractals fit in the "handy design approach" category |
Log-Periodic Antenna Design
On Mon, 24 Nov 2008 14:02:10 -0600, Cecil Moore
wrote: predictability predictability I dare say the Yea-sayers cannot predict any specific, practical, fractal characteristic when given fractal mathematical models. For the inverse (starting with the practical instead of the mathematical model) one very simple test: give the mathematical model for a single fractal antenna specifically resonant on each frequency: 1.85MHz; 3.8MHz; 7.15MHz; 10.13MHz; 14.15MHz; 18.11MHz; 21.2MHz; 24.93MHz; 28.5MHz, to within the margins of any Ham band represented by the single frequency offered. Solution: Biconical; LPDA (barring, of course, no one can give the fractal mathematical models). Of course, the joke here is that these are neither very gainful, nor small - the presumed boon of fractal invention. Yet no other "fractal" can describe this antenna above. Those "fractals" that come close (maybe covering 3 of the 9 bands) aren't small or gainful either. Sometimes you just can't win for trying either. Going to specifics, what is the mathematical model (not just a word salad description) for a Sierpinksi Gasket? Using that mathematical model (what students call plug-n-chug for solving an equation), show the free space best gain at its sixth iteration, fourth resonance (the 30M band of the description above). What is the greatest physical dimension of this 9 band antenna? What would be its greatest physical dimension if implemented in a fourth iteration Triadic Cantor (if, in fact, one were possible to support these resonances)? So, a specific fractal antenna, a specific implementation, a specific characteristic - and years before anyone here will offer a demonstration of -dare I say it?- predictability. Hasn't happened from any other correspondents here to this board in the entire history of the topic. In that same history, not one other scribbler has offered a link to someone who can do their work for them. Fractals, always amusing. |
Log-Periodic Antenna Design
On Nov 24, 4:02*pm, Richard Clark wrote:
On Mon, 24 Nov 2008 14:02:10 -0600, Cecil Moore wrote: predictability predictability I dare say the Yea-sayers cannot predict any specific, practical, fractal characteristic when given fractal mathematical models. For the inverse (starting with the practical instead of the mathematical model) one very simple test: * * * * give the *mathematical model for a single fractal * * * * antenna specifically resonant on each frequency: * * * * 1.85MHz; * * * * 3.8MHz; * * * * 7.15MHz; * * * * 10.13MHz; * * * * 14.15MHz; * * * * 18.11MHz; * * * * 21.2MHz; * * * * 24.93MHz; * * * * 28.5MHz, to within the margins of any Ham band represented by the single frequency offered. Solution: * * * * Biconical; * * * * LPDA (barring, of course, no one can give the fractal mathematical models). Of course, the joke here is that these are neither very gainful, nor small - the presumed boon of fractal invention. *Yet no other "fractal" can describe this antenna above. *Those "fractals" that come close (maybe covering 3 of the 9 bands) aren't small or gainful either. *Sometimes you just can't win for trying either. Going to specifics, what is the *mathematical model (not just a word salad description) for a Sierpinksi Gasket? *Using that mathematical model (what students call plug-n-chug for solving an equation), show the free space best gain at its sixth iteration, fourth resonance (the 30M band of the description above). What is the greatest physical dimension of this 9 band antenna? *What would be its greatest physical dimension if implemented in a fourth iteration Triadic Cantor (if, in fact, one were possible to support these resonances)? So, a specific fractal antenna, a specific implementation, a specific characteristic - and years before anyone here will offer a demonstration of -dare I say it?- *predictability. *Hasn't happened from any other correspondents here to this board in the entire history of the topic. *In that same history, not one other scribbler has offered a link to someone who can do their work for them. Fractals, always amusing. Fractal design may prove as good of a way of shrinking an antenna as any other. Its just pure BS to think it is going to let you make a smaller antenna with the same gain as the full size antenna it was derived from. It is Mega BS to think that you are going to shrink the antenna and achive gain because of anything the fractals will contribute. Jimmie |
Log-Periodic Antenna Design
Richard Clark wrote:
For the inverse (starting with the practical instead of the mathematical model) one very simple test: give the mathematical model for a single fractal antenna specifically resonant on each frequency: 1.85MHz; 3.8MHz; 7.15MHz; 10.13MHz; 14.15MHz; 18.11MHz; 21.2MHz; 24.93MHz; 28.5MHz, to within the margins of any Ham band represented by the single frequency offered. Since fractal antennas are finding practical applications when etched on a PC board, your discussion is about as moot at a 160m rotatable Yagi proving that rotatable Yagis are not feasible. -- 73, Cecil http://www.w5dxp.com |
Log-Periodic Antenna Design
On Mon, 24 Nov 2008 17:10:00 -0600, Cecil Moore
wrote: Since fractal antennas are finding practical applications when etched on a PC board Like I said - nothing predictable, no math model, etc. etc. etc. Imagine, an antenna on a PC board - the miracle of the 3rd Millennium! |
Log-Periodic Antenna Design
"Rich Grise" wrote in message ... Or, does anyone have a UHF-TV log-periodic design that they'd share? :-) Thanks, Rich Lo and behold, here is one http://tinyurl.com/665r5a but it's a throw-back to a simpler time when the HP42S calculator was an engineer's prized tool. If you have a 42S, punch it in and use it. Otherwise, this is mainly a learning tool to show how simple the calculations are. I think this design could be put onto a Lotus123 calculating spread sheet where all the output data windows would suddenly by filled up upon entering the needed input data. |
Log-Periodic Antenna Design
Jim Lux wrote:
. . . http://ieeexplore.ieee.org/Xplore/lo...number=1610336 If you are a member of IEEE, you can access this paper: Multiband behavior of wideband Sierpinski fractal bow-tie antenna Yamini, A.H.; Soleimani, M. Microwave Conference, 2005 European Volume 3, Issue , 4-6 Oct. 2005 Page(s): 4 pp. - Digital Object Identifier 10.1109/EUMC.2005.1610336 interesting paper.. . . . I think you have to be a member of the Microwave Theory & Techniques Society to it. I'm a member of the IEEE and several of its Societies, but not that one, and I'm denied access to the paper. Too bad it wasn't published in Ant & Prop. Roy Lewallen, W7EL |
Log-Periodic Antenna Design
"Chuck Olson" wrote in message ... "Rich Grise" wrote in message ... Or, does anyone have a UHF-TV log-periodic design that they'd share? :-) Thanks, Rich Lo and behold, here is one http://tinyurl.com/665r5a but it's a throw-back to a simpler time when the HP42S calculator was an engineer's prized tool. If you have a 42S, punch it in and use it. Otherwise, this is mainly a learning tool to show how simple the calculations are. I think this design could be put onto a Lotus123 calculating spread sheet where all the output data windows would suddenly by filled up upon entering the needed input data. Sorry I didn't fully describe how to get the file. It's a Word document, so the URL above takes you to a page where you can choose "download", and then you can open it with Microsoft Word. Chuck W6PKP |
Log-Periodic Antenna Design
"Chuck Olson" wrote in message ... "Rich Grise" wrote in message ... Or, does anyone have a UHF-TV log-periodic design that they'd share? :-) Thanks, Rich Lo and behold, here is one http://tinyurl.com/665r5a but it's a throw-back to a simpler time when the HP42S calculator was an engineer's prized tool. If you have a 42S, punch it in and use it. Otherwise, this is mainly a learning tool to show how simple the calculations are. I think this design could be put onto a Lotus123 calculating spread sheet where all the output data windows would suddenly by filled up upon entering the needed input data. I'm really disappointed in the comcast customer's website - - I tried to access the program later in the evening and found it required I sign in - - even though I specified the file to be "public". Let me know if you have trouble getting the file. I would appreciate any recommendation for a better way to access the Word document than the use of this comcast facility. |
Log-Periodic Antenna Design
In article ,
"Ralph Mowery" wrote: "Rich Grise" wrote in message ... My current UHF antenna is a 14" Radio Shack clip lead clipped from the center of my coax to the venetian blind. I have to hand-adjust it for the channel, weather conditions, phase of the moon, etc. I can do this because I can _see_ an indication of signal strength. Well, with this new Fascist "No More Free TV" crap, I'm gonna need a real UHF antenna. My budget is exceedingly limited, but I have a supply of materials (GTAW filler rod, with some coppery-colored coating, so it solders like a dream, and is as stiff as piano wire) to build an antenna with. It may not take too much antenna. I picked up one of the converter boxes and hooked it to a 432 mhz beam at 70 feet and got 21 stations on the auto tune. Then to a 9 element M2 2 meter bem and it picked up 29 stations. This was at the end of about 130 feet of low loss rg-8 size coax and then 25 feet of rg-6. Several of the stations were the same transmitter,but differant chanels on the TV. no more free tv?? where do you live? here in the usa over the air tv is , was and shall remain free in feb it will switch to digital however shall still be free |
No More Free TV (was Log-Periodic Antenna Design)
ml wrote:
In article , "Ralph Mowery" wrote: "Rich Grise" wrote in message ... My current UHF antenna is a 14" Radio Shack clip lead clipped from the center of my coax to the venetian blind. I have to hand-adjust it for the channel, weather conditions, phase of the moon, etc. I can do this because I can _see_ an indication of signal strength. Well, with this new Fascist "No More Free TV" crap, I'm gonna need a real UHF antenna. My budget is exceedingly limited, but I have a supply of materials (GTAW filler rod, with some coppery-colored coating, so it solders like a dream, and is as stiff as piano wire) to build an antenna with. It may not take too much antenna. I picked up one of the converter boxes and hooked it to a 432 mhz beam at 70 feet and got 21 stations on the auto tune. Then to a 9 element M2 2 meter bem and it picked up 29 stations. This was at the end of about 130 feet of low loss rg-8 size coax and then 25 feet of rg-6. Several of the stations were the same transmitter,but differant chanels on the TV. no more free tv?? where do you live? here in the usa over the air tv is , was and shall remain free in feb it will switch to digital however shall still be free Digital is a major step toward "conditional access". |
No More Free TV (was Log-Periodic Antenna Design)
"Dave" wrote in message ... Digital is a major step toward "conditional access". So is analog. If you don't have the proper reciever, you can't pick it up. Just a different format. |
No More Free TV (was Log-Periodic Antenna Design)
On Tue, 25 Nov 2008 13:51:24 +0000, Dave wrote:
Digital is a major step toward "conditional access". And the 80 year old method of modulation, a combination of pulse, FM, and analog was just as much a restriction to specialized equipment. If you tried to get TV on your XTAL radio, it would be like listening to an encrypted secure network. If you stood out in a field and tried to listen to AM radio waves (without even the boon of that XTAL radio), you would still suffer "conditional access." So, what is the big deal? 73's Richard Clark, KB7QHC |
Log-Periodic Antenna Design
On Tue, 25 Nov 2008 05:23:33 -0500, ml wrote:
in feb it will switch to digital however shall still be free Until you get to the requirement to line the pockets of the converter hawkers. Thanks, Rich |
No More Free TV (was Log-Periodic Antenna Design)
On Tue, 25 Nov 2008 07:26:28 -0800, CW wrote:
"Dave" wrote in message Digital is a major step toward "conditional access". So is analog. If you don't have the proper reciever, you can't pick it up. Just a different format. Even they used to be free, if you knew where to dumpster-dive. ;-) Cheers! Rich |
No More Free TV (was Log-Periodic Antenna Design)
On Tue, 25 Nov 2008 10:17:44 -0800, Richard Clark wrote:
So, what is the big deal? Being required to turn over my hard-earned cash to further enrich the rich fat white executives. Thanks, Rich |
Log-Periodic Antenna Design
On Mon, 24 Nov 2008 16:07:35 -0800, Chuck Olson wrote:
"Rich Grise" wrote in message Or, does anyone have a UHF-TV log-periodic design that they'd share? :-) Lo and behold, here is one http://tinyurl.com/665r5a but it's a throw-back to a simpler time when the HP42S calculator was an engineer's prized tool. If you have a 42S, punch it in and use it. Otherwise, this is mainly a learning tool to show how simple the calculations are. I think this design could be put onto a Lotus123 calculating spread sheet where all the output data windows would suddenly by filled up upon entering the needed input data. Too late! I've already built the 4-bay bowtie: http://www.youtube.com/watch?v=EWQhlmJTMzw But I used ER70S-2 1/16 weld filler rod (stiffer than a coathanger, and copper-plated; solders like a dream): http://mysite.verizon.net/richgrise/...QuadBowTie.jpg And it works just spiffy! I had to go to Whittier Electronics to get the balun, since RS seems to have dropped them from their line-up: http://www.whittierelectronics.com/ It was $2.99; the rest of the antenna was free. :-) (yes, I'm really that broke. )-; ) Thanks, Rich |
Log-Periodic Antenna Design
In article , ml wrote:
no more free tv?? where do you live? here in the usa over the air tv is , was and shall remain free in feb it will switch to digital however shall still be free The current situation is somewhat analogous to what happened, decades ago, when television in the U.S. moved from VHF-only to VHF-plus-UHF. Everybody who wanted to receive the full set of channels, had to either buy a new TV, or buy a UHF block converter so that they could downshift the UHF frequencies to a VHF frequency that their existing TV set could receive. The television signal is, and will remain, free to receive (or, rather, its transmission is funded by advertising). There is no fee on the user to receive the TV signal. The equipment needed to receive TV signals in the U.S. is not, and never has been free. This is a somewhat bigger switch-over, technology-wise, than the expansion to UHF some years ago. Whether it's a Good Thing or a Bad Thing is, I think, much more of a personal conclusion than anything that can be decided objectively. -- Dave Platt AE6EO Friends of Jade Warrior home page: http://www.radagast.org/jade-warrior I do _not_ wish to receive unsolicited commercial email, and I will boycott any company which has the gall to send me such ads! |
No More Free TV (was Log-Periodic Antenna Design)
In rec.radio.amateur.antenna Richard The Dreaded Libertarian wrote:
On Tue, 25 Nov 2008 10:17:44 -0800, Richard Clark wrote: So, what is the big deal? Being required to turn over my hard-earned cash to further enrich the rich fat white executives. A converter box can be had for about the same amount of cash as a cup of coffee after using the coupon, so that arguement is moot. What "rich fat white executives" do you think are getting enriched by the switch since almost all the converter boxes are made in China? -- Jim Pennino Remove .spam.sux to reply. |
Log-Periodic Antenna Design
In rec.radio.amateur.antenna Richard The Dreaded Libertarian wrote:
On Tue, 25 Nov 2008 05:23:33 -0500, ml wrote: in feb it will switch to digital however shall still be free Until you get to the requirement to line the pockets of the converter hawkers. Thanks, Rich The converter boxes are essentially free with the coupon and you get two of them. -- Jim Pennino Remove .spam.sux to reply. |
No More Free TV (was Log-Periodic Antenna Design)
Richard The Dreaded Libertarian wrote:
On Tue, 25 Nov 2008 10:17:44 -0800, Richard Clark wrote: So, what is the big deal? Being required to turn over my hard-earned cash to further enrich the rich fat white executives. After the $40 free coupon, the DTV converter box costs $10. If you skip three Whoppers, you've got the money and are a healthier human being to boot. :-) -- 73, Cecil http://www.w5dxp.com |
FCC TV Band Devices
"Dave" wrote in message
... The FCC and the TV broadcasters looked the other way because there is no evidence that such activity has ever caused any interference. I can get 6 microphones to work in an occupied analog TV channel and neither notices the other. OK. I don't have a big problem with folks using frequencies they're not assigned when there isn't an interference issue, although I also don't have a whole lot of sympathy for those same folks if one day they *are* interfered with by assigned users. The TV Band Devices the FCC has recently begun the process of authorizing are way more damaging than a 50 mW 65 kHz deviation FM signal. What are the power levels? Presumably the occupied spectrum is potentially many tens of MHz? Luckily, these devices will not be allowed anywhere near where I work. The FCC has banned them from the 13 biggest cities, and from within a kilometer of a venue or stadium using wireless microphones. The proposed rules do not require a Part 74 license for these protections. If these are consumer-type devices, realistically how will the FCC stop their use in those 13 cities? It'll be like GMRS where technically everyone's supposed to be licensed yet, in actuality, I imagine that well under 1% of the actual users a If the consumer can buy a radio off-the-shop at Wal*Mart, there'll use it wherever they want, regardless of what FCC rules say. ---Joel |
No More Free TV (was Log-Periodic Antenna Design)
Is someone holding a gun on you? It's no different than "being forced" to
buy a TV. You can always do what I do and don't watch. TV is the greatest time waster invented by man. "Richard The Dreaded Libertarian" wrote in message ... On Tue, 25 Nov 2008 10:17:44 -0800, Richard Clark wrote: So, what is the big deal? Being required to turn over my hard-earned cash to further enrich the rich fat white executives. Thanks, Rich |
No More Free TV (was Log-Periodic Antenna Design)
In rec.radio.amateur.antenna Cecil Moore wrote:
Richard The Dreaded Libertarian wrote: On Tue, 25 Nov 2008 10:17:44 -0800, Richard Clark wrote: So, what is the big deal? Being required to turn over my hard-earned cash to further enrich the rich fat white executives. After the $40 free coupon, the DTV converter box costs $10. If you skip three Whoppers, you've got the money and are a healthier human being to boot. :-) There are several outfits with converter boxes for $40.01, which makes your cost 1 cent. -- Jim Pennino Remove .spam.sux to reply. |
Log-Periodic Antenna Design
"Rich Grise" wrote in message ... On Mon, 24 Nov 2008 16:07:35 -0800, Chuck Olson wrote: "Rich Grise" wrote in message Or, does anyone have a UHF-TV log-periodic design that they'd share? :-) Lo and behold, here is one http://tinyurl.com/665r5a but it's a throw-back to a simpler time when the HP42S calculator was an engineer's prized tool. If you have a 42S, punch it in and use it. Otherwise, this is mainly a learning tool to show how simple the calculations are. I think this design could be put onto a Lotus123 calculating spread sheet where all the output data windows would suddenly by filled up upon entering the needed input data. Too late! I've already built the 4-bay bowtie: http://www.youtube.com/watch?v=EWQhlmJTMzw But I used ER70S-2 1/16 weld filler rod (stiffer than a coathanger, and copper-plated; solders like a dream): http://mysite.verizon.net/richgrise/...QuadBowTie.jpg And it works just spiffy! I had to go to Whittier Electronics to get the balun, since RS seems to have dropped them from their line-up: http://www.whittierelectronics.com/ It was $2.99; the rest of the antenna was free. :-) (yes, I'm really that broke. )-; ) Thanks, Rich Thanks, Rich - - it looks great. I'm going to try putting one together, too - - the phased quad bow-tie is very popular so it must be a good performer. And the price is right. Chuck |
No More Free TV (was Log-Periodic Antenna Design)
On Tue, 25 Nov 2008 20:15:01 +0000, jimp wrote:
There are several outfits with converter boxes for $40.01, which makes your cost 1 cent. WHERE???????????!!! Thanks, Rich |
No More Free TV (was Log-Periodic Antenna Design)
On Tue, 25 Nov 2008 12:06:45 -0800, CW wrote:
Is someone holding a gun on you? It's no different than "being forced" to buy a TV. You don't have to if you know where to dumpster-dive. You can always do what I do and don't watch. I hate self-righteous peopoe almost as much as I hate rap. Thanks, Rich |
No More Free TV (was Log-Periodic Antenna Design)
On Tue, 25 Nov 2008 18:49:26 GMT, Richard The Dreaded Libertarian
wrote: On Tue, 25 Nov 2008 10:17:44 -0800, Richard Clark wrote: So, what is the big deal? Being required to turn over my hard-earned cash to further enrich the rich fat white executives. Required? You've been lined up against the wall for a shakedown so you can watch TV? With porn free on the Internet, the only successful economic model is they pay you to watch Digital TV for FREE! And they DO! I think Madison avenue would have those rich fat white executives gutted (too slow to move anyway - are you talking about AIG or the Paleolithic RNC?) before their hooves clattered halfway down the alley you've been suckered into. 73's Richard Clark, KB7QHC |
No More Free TV (was Log-Periodic Antenna Design)
In rec.radio.amateur.antenna Rich Grise wrote:
On Tue, 25 Nov 2008 20:15:01 +0000, jimp wrote: There are several outfits with converter boxes for $40.01, which makes your cost 1 cent. WHERE???????????!!! Thanks, Rich Google search for HDTV converter leads to sites with price comparisons. My coupons are due any day and I was price shopping. -- Jim Pennino Remove .spam.sux to reply. |
No More Free TV (was Log-Periodic Antenna Design)
Richard The Dreaded Libertarian wrote: On Tue, 25 Nov 2008 10:17:44 -0800, Richard Clark wrote: So, what is the big deal? Being required to turn over my hard-earned cash to further enrich the rich fat white executives. There are no rich fat black executives ? Graham |
Log-Periodic Antenna Design
Rich Grise wrote:
Where I'm sitting here in Whittier, KABC 7 is so strong I can get it without even a cable plugged in! It's 50, 56, and 58 I worry about; 2-13 and 28 are covered; I'm looking forward to seeing if my new bowtie (from that youtube video, but with ER708-2 x 1/16 filler rod) will pick up PAX on 30. They have some nice oldies sometimes. Frequency re-allocations were mentioned up the thread in I'm surprized no one has mentioned http://www.tvfool.com Here's what you can expect to get in one part of Whittier with a 20' mast: http://www.tvfool.com/?option=com_wr...d%3dea7348065e (The results are a graphical representation of the data so it's not searchable with a text search utility.) 8-( Here's the version that isn't scrunched into the middle of the screen: (Right-click; Show only this frame) http://www.tvfool.com/modeling/?id=ea7348065e (Your exact zip code and elevation may give different results.) The lowest commercial channel you will get is the faith-healer/preachy-movie channel reallocated from 40 to 23. The *all will move below 52* statement in Platt's wasn't accurate. While KDOC56 will move to 32, KLCS58 will move to 41, and KOCE50 will move to 48, **KCOP13 will move to 66 and KCET28 will move to 59**. |
Log-Periodic Antenna Design
"JeffM" wrote in message ... snip The *all will move below 52* statement in Platt's wasn't accurate. While KDOC56 will move to 32, KLCS58 will move to 41, and KOCE50 will move to 48, **KCOP13 will move to 66 and KCET28 will move to 59**. Careful. The channels you mention as "will move" are already operating digital on the "will move to" channels. Some will stay where they are. At Transition, the four LA stations on analog VHF-HI channels, 7, 9, 11 and 13, will secure their digital UHF transmitters and initiate digital transmissions on their historic (analog) channels. After Transition, no so-called "regular TV" will be on channels 52 and above. Other services have won bids for those channels. Qualcomm has channel 55 for MediFLO mobile TV, etc. Pls see http://www.rabbitears.info/dtr.php and scroll downpage past New York to Los Angeles (they're in market-size order). See the fourth, fifth and sixth columns for each station's FCC assignments: analog, interim digital and final digital. It's all there. I hope this helps. |
No More Free TV (was Log-Periodic Antenna Design)
CW wrote:
"Dave" wrote in message ... Digital is a major step toward "conditional access". So is analog. If you don't have the proper reciever, you can't pick it up. Just a different format. That's not what conditional access means. |
FCC TV Band Devices
Joel Koltner wrote:
"Dave" wrote in message ... The FCC and the TV broadcasters looked the other way because there is no evidence that such activity has ever caused any interference. I can get 6 microphones to work in an occupied analog TV channel and neither notices the other. OK. I don't have a big problem with folks using frequencies they're not assigned when there isn't an interference issue, although I also don't have a whole lot of sympathy for those same folks if one day they *are* interfered with by assigned users. The TV Band Devices the FCC has recently begun the process of authorizing are way more damaging than a 50 mW 65 kHz deviation FM signal. What are the power levels? Presumably the occupied spectrum is potentially many tens of MHz? Luckily, these devices will not be allowed anywhere near where I work. The FCC has banned them from the 13 biggest cities, and from within a kilometer of a venue or stadium using wireless microphones. The proposed rules do not require a Part 74 license for these protections. If these are consumer-type devices, realistically how will the FCC stop their use in those 13 cities? It'll be like GMRS where technically everyone's supposed to be licensed yet, in actuality, I imagine that well under 1% of the actual users a If the consumer can buy a radio off-the-shop at Wal*Mart, there'll use it wherever they want, regardless of what FCC rules say. ---Joel Each TVBD will be addressable and can be shut off when it consults the database. The top 13 cities thing is probably an oversight, but it's in the proposed law. The proposed power for a portable device is 100 mW, except on a first-adjacent to a DTV station, which is 40 mW. This makes no sense because the 2nd adjacent channel is more likely to interfere. |
FCC TV Band Devices
Thanks for the information, Dave.
"Dave" wrote in message ... Each TVBD will be addressable and can be shut off when it consults the database. The database is internal to the TVBD and indexed by a built-in GPS receiver telling the TVBD where it is? ---Joel |
FCC TV Band Devices
Joel Koltner wrote:
Thanks for the information, Dave. "Dave" wrote in message ... Each TVBD will be addressable and can be shut off when it consults the database. The database is internal to the TVBD and indexed by a built-in GPS receiver telling the TVBD where it is? ---Joel The database will be on the internet. How the device will connect to the internet is not stated in the ruling, but if the device cannot transmit until it has consulted the database it won't be by talking to another TVBD. |
No More Free TV (was Log-Periodic Antenna Design)
"Dave" wrote in message ... CW wrote: "Dave" wrote in message ... Digital is a major step toward "conditional access". So is analog. If you don't have the proper reciever, you can't pick it up. Just a different format. That's not what conditional access means. Conditional access has been done with analog -- but not well. I sucessfully defeated analog scrambling with two different home-brew devices but I never tried digital. Too hard. It's much easier to hard-code C/A with digital. Just my two cents. |
Log-Periodic Antenna Design
On Nov 19, 3:45*pm, Rich Grise wrote:
My current UHF antenna is a 14" Radio Shack clip lead clipped from the center of my coax to the venetian blind. I have to hand-adjust it for the channel, weather conditions, phase of the moon, etc. I can do this because I can _see_ an indication of signal strength. Well, with this new Fascist "No More Free TV" crap, I'm gonna need a real UHF antenna. My budget is exceedingly limited, but I have a supply of materials (GTAW filler rod, with some coppery-colored coating, so it solders like a dream, and is as stiff as piano wire) to build an antenna with. But I've been searching the web for some weeks now, and I can't seem to find any kind of formula, except there was this program I downloaded - LPDA.EXE, which runs on DOS. Unfortunately, it's in Russian or Polish or Uzbekistani - one of those East Yurp languages. Here's a screen snap:http://mysite.verizon.net/richgrise/...rog-Output.gif Which I went through pretty much by-guess-and-by-gosh - can anybody read that stuff? There are a lot of factors I don't know about, like "Tau", and all of the specific designs on the web are flat - something is telling me I want one of those pyramid-shaped ones, but I really don't know the difference (between that and flat) - it's probably something to do with bandwidth or F/B ratio or whatever. My local library has no ARRL Antenna Book (!), and did I mention I have a seriously limited budget? So, how do I pursue this? It'd be nice to have a program that will calculate the whole thing for me, but am I dreaming? If I want to send myself to Log-Periodic School, where should I start? Or, does anyone have a UHF-TV log-periodic design that they'd share? :-) Thanks, Rich I suspect Rich is Virginia Newbon, she's using at least 40 male aliases in most newsgroups existant. Literally, that's hundreds if not a thousand. |
No More Free TV (was Log-Periodic Antenna Design)
TV has never been 'free'. you pay for it with every product you purchase
that is advertised on tv. and of course you pay for it in taxes, and also in product purchases from sponsors, for 'public' tv channels. tanstaafl! |
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