Hey Jeff, what u think the dBi is for this?
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From: John Navas on 6 Aug 2010 20:24 On Sat, 7 Aug 2010 00:11:49 +0000 (UTC), in <i3i8c4$7pa$1(a)speranza.aioe.org>, dakid <dakid(a)nospam.org> wrote: >http://www.hawkingtech.com/products/productlist.php?CatID=33 >&FamID=58&ProdID=374 > >They say 2-12? so they don't really know? or what? >Any idea what it is likely to be from indoors apartment >building? Price is kinda high. <http://goo.gl/EhEF>
From: John Navas on 6 Aug 2010 20:27 On Fri, 06 Aug 2010 17:24:46 -0700, in <at9p56piceha1tvtu4nfl7ghf8m0gsjtpv(a)4ax.com>, John Navas <spamfilter1(a)navasgroup.com> wrote: >On Sat, 7 Aug 2010 00:11:49 +0000 (UTC), in ><i3i8c4$7pa$1(a)speranza.aioe.org>, dakid <dakid(a)nospam.org> wrote: > >>http://www.hawkingtech.com/products/productlist.php?CatID=33 >>&FamID=58&ProdID=374 >> >>They say 2-12? so they don't really know? or what? >>Any idea what it is likely to be from indoors apartment >>building? Price is kinda high. > ><http://goo.gl/EhEF> They actually say: The HA12W Window Antenna boosts the antenna power of standard antennas from a minimal 2dBi to a more potent 12dBi. In other words, 12 dBi, not a range. Price looks not unreasonable to me. -- John FAQ for Wireless Internet: <http://wireless.navas.us> FAQ for Wi-Fi: <http://wireless.navas.us/wiki/Wi-Fi> Wi-Fi How To: <http://wireless.navas.us/wiki/Wi-Fi_HowTo> Fixes to Wi-Fi Problems: <http://wireless.navas.us/wiki/Wi-Fi_Fixes>
From: George on 7 Aug 2010 09:52 On 8/6/2010 8:11 PM, dakid wrote: > http://www.hawkingtech.com/products/productlist.php?CatID=33 > &FamID=58&ProdID=374 > > They say 2-12? so they don't really know? or what? > Any idea what it is likely to be from indoors apartment > building? Price is kinda high. Not Jeff, it is stated a little clumsily "The HA12W Window Antenna boosts the antenna power of standard antennas from a minimal 2dBi to a more potent 12dBi." They are saying their antenna is 12dbi compared to a "standard antenna". $50 is not an unusual price for an antenna.
From: Jeff Liebermann on 7 Aug 2010 13:08 On Sat, 7 Aug 2010 00:11:49 +0000 (UTC), dakid <dakid(a)nospam.org> wrote: >http://www.hawkingtech.com/products/productlist.php?CatID=33&FamID=58&ProdID=374 > >They say 2-12? so they don't really know? or what? >Any idea what it is likely to be from indoors apartment >building? Price is kinda high. Note that it's a "legacy product" which is a nice term for possible difficulties finding one to purchase. The PDF data sheet at the bottom of the web page is a little better. ... Gain: 12dBi ... Radiation: Directional ... Polorization: Linear, Vertical ... H-Plane: 84 deg ... E-Plane: 23 deg ... Dimensions: 327mm x 80mm x 22mm I was going to check what's inside by searching the FCC ID database, but it's a weekend, when the FCC servers usually prefer to crash. Error Executing Database Query. weblogic.common.resourcepool.ResourceDisabledException: Pool OETDataSource is disabled, cannot allocate resources to applications.. The error occurred on line 26. Sigh... Maybe some stimulus money will help. Judging by the size, and the beam widths, I would guess(tm) that the guts might be a colinear vertical or Franklin antenna. Something like this: <http://802.11junk.com/jeffl/antennas/AMOS-5/index.html> but with only 3 elements instead of 5. There are many mutations of this design so I can't build a model without clues as to what's inside. I can make a really bad guess as to the gain, by starting with a flat plate reflector and a dipole. See: <http://802.11junk.com/jeffl/antennas/FullWavePlateReflector/index.html> That's 8dBi gain, with an 80 degree beamwidth in both axes. If I cut the beam width in half, the gain increases about 2 dB. The horizontal beamwidth is about 80 degrees, so I can leave that alone. Cutting the vertical (E-Plane) in half, twice adds 4dB gain for a total of 8dBi + 4dB = 12dBi gain Yeah, I would say it's possible that it has 12dBi gain. Again, this is guesswork, not a calculation, or an endorsement. Another sanity check is the length. 327mm / 125mm = 3 wavelengths The gain of a half wave dipole is about 2dBi. Double the length, and the gain increases by 3dB. So, 1 wavelength (with phasing stubs) will be 5dBi, 2 wavelengths yield 8dBi, and another wavelength will bring it up to about 9dBi. A reflector will double the signal for an additional 3dB gain, thus yielding the required 12dBi. Yep, it's possible. -- Jeff Liebermann jeffl(a)cruzio.com 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558
From: Jeff Liebermann on 7 Aug 2010 13:49
On Sat, 7 Aug 2010 00:11:49 +0000 (UTC), dakid <dakid(a)nospam.org> wrote: >http://www.hawkingtech.com/products/productlist.php?CatID=33&FamID=58&ProdID=374 Or, just build your own: <http://pe2er.nl/wifisector/> <http://yu1aw.ba-karlsruhe.de/amos_antennas.htm> Typical photo: <http://yu1aw.ba-karlsruhe.de/Amos%20at%20work.jpg> Hmmm.... looking at the characteristics for the AMOS-3 (3 element Franklin) at: <http://yu1aw.ba-karlsruhe.de/amos_antennas.htm> it has only 10 or 11dBi max gain. Close, but not the rated 12dBi for the Hawking Tech antenna. In the inverted AMOS-3, the 85 degree horizontal is right, but with only 10 degrees of vertical beamwidth, it's probably NOT the same as whatever is inside the Hawking Tech antenna. Oh well... bad guess(tm). -- Jeff Liebermann jeffl(a)cruzio.com 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558 |