Comments for Antenna Magus blog http://www.antennamagus.com/blog Find out what is cooking inside Magus. Mon, 30 Aug 2010 08:44:49 +0200 http://wordpress.org/?v=2.8.4 hourly 1 Comment on Introducing the new !Phone by Robert Kellerman http://www.antennamagus.com/blog/?p=613&cpage=1#comment-2797 Robert Kellerman Mon, 30 Aug 2010 08:44:49 +0000 http://www.antennamagus.com/blog/?p=613#comment-2797 Hi Joe Thanks for the comment and for pointing that out. I think the problem with excluding the hand is that in reality the peak SAR value is likely to be in the hand tissue seeing that the tendency is to move the antennas far away from the ear or head. Higher SAR values is probably less risky in the hand than in the head though. Hi Joe

Thanks for the comment and for pointing that out. I think the problem with excluding the hand is that in reality the peak SAR value is likely to be in the hand tissue seeing that the tendency is to move the antennas far away from the ear or head. Higher SAR values is probably less risky in the hand than in the head though.

]]> Comment on Introducing the new !Phone by Joe Stevens http://www.antennamagus.com/blog/?p=613&cpage=1#comment-2682 Joe Stevens Fri, 27 Aug 2010 05:21:46 +0000 http://www.antennamagus.com/blog/?p=613#comment-2682 Quoting the above: "The SAR value that is printed in a device’s user manual needs to be minimized to keep the public happy in spite of the fact that SAR in the hand is ignored during measurements. In practical situations more power needs to be radiated to compensate for signal loss due to the vicinity of the hand – increasing the actual SAR and reducing the phone’s battery life." The phones are tested for SAR at maximum power. If more power is required to maintain the link, the phone cannot increase the power, just the radio link will suffer. So the effect of the hand actually lowers the sar, because the efficiency would decrease. Hence, the test method is actually worst case. Quoting the above:

“The SAR value that is printed in a device’s user manual needs to be minimized to keep the public happy in spite of the fact that SAR in the hand is ignored during measurements. In practical situations more power needs to be radiated to compensate for signal loss due to the vicinity of the hand – increasing the actual SAR and reducing the phone’s battery life.”

The phones are tested for SAR at maximum power. If more power is required to maintain the link, the phone cannot increase the power, just the radio link will suffer. So the effect of the hand actually lowers the sar, because the efficiency would decrease. Hence, the test method is actually worst case.

]]> Comment on Making your own Bi-Quad (Wi-Fi) antenna by Neilen Marais http://www.antennamagus.com/blog/?p=216&cpage=1#comment-1797 Neilen Marais Mon, 26 Jul 2010 07:31:45 +0000 http://www.antennamagus.com/blog/?p=216#comment-1797 Well, I think you're asking what to connect your biquad antenna to ;) What you want is a wifi router that has an external antenna port. The software on the router should be able to tell you the relative signal strength (usually through a local web-page served by the router). If you have a wifi card/usb dongle that has external antenna port, you would need some software. I'm not sure what to use, although a quick google http://www.google.co.za/search?q=check+wifi+signal+strength+software+windows Seems to yield useful stuff like http://download.cnet.com/WIFI-Signal-Strength/3000-2085_4-10663562.html Well, I think you’re asking what to connect your biquad antenna to ;) What you want is a wifi router that has an external antenna port. The software on the router should be able to tell you the relative signal strength (usually through a local web-page served by the router). If you have a wifi card/usb dongle that has external antenna port, you would need some software. I’m not sure what to use, although a quick google http://www.google.co.za/search?q=check+wifi+signal+strength+software+windows
Seems to yield useful stuff like http://download.cnet.com/WIFI-Signal-Strength/3000-2085_4-10663562.html

]]> Comment on Making your own Bi-Quad (Wi-Fi) antenna by yusuf http://www.antennamagus.com/blog/?p=216&cpage=1#comment-1734 yusuf Fri, 23 Jul 2010 13:07:29 +0000 http://www.antennamagus.com/blog/?p=216#comment-1734 sir i have some confution that provider provided adsl(not in use now) is it work as router?N i saw so many biquad antena but nobody is telling in pc which software require to chek signal n wifi.plz provide me full theary so plz clarify coz i m new in this n i m learning fully with on internet. my id yusmusuf@yahoo.com plz reply in advance i m very thankful to u. sir
i have some confution that provider provided adsl(not in use now) is it work as router?N i saw so many biquad antena but nobody is telling in pc which software require to chek signal n wifi.plz provide me full theary
so plz clarify coz i m new in this n i m learning fully with on internet.
my id yusmusuf@yahoo.com
plz reply in advance i m very thankful to u.

]]> Comment on Cylindrical dipole antenna with quarter-wave balun feed by admin http://www.antennamagus.com/blog/?p=166&cpage=1#comment-1468 admin Fri, 09 Jul 2010 13:38:06 +0000 http://www.antennamagus.com/blog/?p=166#comment-1468 Hi I think the comment box removed the spaces in your ASCII sketch. I added a sketch below the last image of this blog (see above), which should help to illustrate what I meant in my previous response. Hi I think the comment box removed the spaces in your ASCII sketch. I added a sketch below the last image of this blog (see above), which should help to illustrate what I meant in my previous response.

]]> Comment on Cylindrical dipole antenna with quarter-wave balun feed by ka http://www.antennamagus.com/blog/?p=166&cpage=1#comment-1460 ka Thu, 08 Jul 2010 22:44:37 +0000 http://www.antennamagus.com/blog/?p=166#comment-1460 Thx for answering. but is that something like this? ------------------ i i --- ---- i i i i i i i i i i i i i i i i i i i i i i i i hollow tube tube w/coax inside Thx for answering. but is that something like this?
——————
i i
— —-
i i i i i i
i i i i i i
i i i i i i
i i i i i i
hollow tube tube w/coax inside

]]> Comment on Cylindrical dipole antenna with quarter-wave balun feed by admin http://www.antennamagus.com/blog/?p=166&cpage=1#comment-1417 admin Mon, 05 Jul 2010 09:23:04 +0000 http://www.antennamagus.com/blog/?p=166#comment-1417 Hi, one of the vertical tubes has a piece of semi-rigid on the inside. The outer of the semi rigid is grounded at the bottom and top of the vertical tube and the inner is connected to the feed pin of the SMA connector and extended through the top of the vertical tube with a bent wire which is connected to the adjacent copper tube (as shown on the image.) Hi, one of the vertical tubes has a piece of semi-rigid on the inside. The outer of the semi rigid is grounded at the bottom and top of the vertical tube and the inner is connected to the feed pin of the SMA connector and extended through the top of the vertical tube with a bent wire which is connected to the adjacent copper tube (as shown on the image.)

]]> Comment on Cylindrical dipole antenna with quarter-wave balun feed by kabukicho2001 http://www.antennamagus.com/blog/?p=166&cpage=1#comment-1386 kabukicho2001 Fri, 02 Jul 2010 22:16:50 +0000 http://www.antennamagus.com/blog/?p=166#comment-1386 Hi, what's inside the vertical tube? is it the same as the printed dipole one? Hi, what’s inside the vertical tube? is it the same as the printed dipole one?

]]> Comment on Making your own Bi-Quad (Wi-Fi) antenna by ka http://www.antennamagus.com/blog/?p=216&cpage=1#comment-1128 ka Sun, 13 Jun 2010 01:52:56 +0000 http://www.antennamagus.com/blog/?p=216#comment-1128 Hello: Many people use h=18 mm. why 30mm for biquad antennas? Hello: Many people use h=18 mm. why 30mm for biquad antennas?

]]> Comment on Building a Cantenna from a Pringles can by Neilen http://www.antennamagus.com/blog/?p=564&cpage=1#comment-1123 Neilen Sat, 12 Jun 2010 09:01:55 +0000 http://www.antennamagus.com/blog/?p=564#comment-1123 Aah, yes, I always had in the back of my mind that a Pringles can isn't quite the right dimensions for a WiFi antenna. Neat trick for getting around the waxy coating though! Amazing that such lo-fi construction techniques can yield a pretty decently working antenna. I do wonder, though, if one could not tweak the antenna to work at 2.45 GHz. Longer feed pin perhaps? Or is it below cut-off of the circular waveguide mode? Aah, yes, I always had in the back of my mind that a Pringles can isn’t quite the right dimensions for a WiFi antenna. Neat trick for getting around the waxy coating though! Amazing that such lo-fi construction techniques can yield a pretty decently working antenna.

I do wonder, though, if one could not tweak the antenna to work at 2.45 GHz. Longer feed pin perhaps? Or is it below cut-off of the circular waveguide mode?

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