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  1. Standard member sonhouse
    Fast and Curious
    18 Jan '13 18:02
    http://phys.org/news/2013-01-ieee-80211ad-marketplace-wigig.html

    Mixed regular wifi signals with a 60 ghz frequency which allows 7 ghz data.

    To make an antenna for 60 ghz, a wavelength of 2.5 cm (one inch) a dipole would be two 1/4 inch sections, total width, 1/2 inch! A yagi at 0.2 wavelength element spacing would yield a 20 element antenna less than 4 inches long 10 cm!
  2. 18 Jan '13 19:14
    Originally posted by sonhouse
    http://phys.org/news/2013-01-ieee-80211ad-marketplace-wigig.html

    Mixed regular wifi signals with a 60 ghz frequency which allows 7 ghz data.

    To make an antenna for 60 ghz, a wavelength of 2.5 cm (one inch) a dipole would be two 1/4 inch sections, total width, 1/2 inch! A yagi at 0.2 wavelength element spacing would yield a 20 element antenna less than 4 inches long 10 cm!
    I have a yagi now that is about 2.5 feet. Be nice to cut that down to 4 inches.
  3. 18 Jan '13 19:28
    7 000 000 000/s^2?
  4. Standard member sonhouse
    Fast and Curious
    21 Jan '13 02:22
    Originally posted by Vartiovuori
    7 000 000 000/s^2?
    A quick note: 300 megahertz is equal to exactly 1 meter. Well very close anyway.

    300 gigahertz would have a wavelength of 1 millimeter. So 60 ghz has a wavelength of 5 mm. A half wave dipole would be 2.5 mm wide at 60 Ghz. About 1/10th of an inch.

    I think I made a mistake. A yagi wants to have element separation of 0.2 wavelength which at 60 ghz is a wavelength of 5 mm so the spacing would be 1 mm. So a 20 element yagi would be 19 mm long and 2.5 mm wide. A bit smaller! That's not exact since some elements would be longer and some a bit shorter but that is a good approximation.
  5. 22 Jan '13 22:01
    Originally posted by sonhouse
    A quick note: 300 megahertz is equal to exactly 1 meter. Well very close anyway.

    300 gigahertz would have a wavelength of 1 millimeter. So 60 ghz has a wavelength of 5 mm. A half wave dipole would be 2.5 mm wide at 60 Ghz. About 1/10th of an inch.

    I think I made a mistake. A yagi wants to have element separation of 0.2 wavelength which at 60 ghz is a ...[text shortened]... ct since some elements would be longer and some a bit shorter but that is a good approximation.
    I think he was questioning your typo where you were giving data rates in ghz/s where you meant Gbps.
  6. Standard member menace71
    Can't win a game of
    24 Jan '13 03:47
    My dad was a HAM radio operator as a matter of fact his call sign was WA6ANR I think he transmitted at Max 50 watts and I believe one of the bands he could operate on was 40 meters ? (I think that is right? not sure?) He built his own antenna I remember it being in the shape of an H but one side had and extra thing sticking out. I believe it was somewhat directional in that sense. At night he would turn it west for some reason? I remember him saying he could receive off the back side of the antenna. He would let me listen at times and it picked up all kinds of other bands even part of the radio AM band. He could only transmit on certain bands. It was very cool

    Manny
  7. Standard member sonhouse
    Fast and Curious
    24 Jan '13 11:13 / 1 edit
    Originally posted by menace71
    My dad was a HAM radio operator as a matter of fact his call sign was WA6ANR I think he transmitted at Max 50 watts and I believe one of the bands he could operate on was 40 meters ? (I think that is right? not sure?) He built his own antenna I remember it being in the shape of an H but one side had and extra thing sticking out. I believe it was somewhat d ...[text shortened]... part of the radio AM band. He could only transmit on certain bands. It was very cool

    Manny
    The extra thing sticking out was undoubtedly a 'gamma match', a section of antenna a few inches separated from the main antenna of a certain length and it allowed the impedance of the feedline and transmitter to match the antenna which meant the transmitter's energy went out the antenna in the form of radiation rather than just bouncing back to the transmitter where it contributes to overheating and burning out parts and such. Do you remember if the H was vertically oriented? If it was horizontal it was probably a beam antenna on a tower of some kind turned with a rotor.

    My call is AI3N, started out with a K6 call, K6QDT, also from California. I just use dipoles, I have a tower ready to go up but right now the individual sections are just on the ground.

    It looks like your dad is a silent key. RIP.
  8. Standard member menace71
    Can't win a game of
    27 Jan '13 00:42
    Originally posted by sonhouse
    The extra thing sticking out was undoubtedly a 'gamma match', a section of antenna a few inches separated from the main antenna of a certain length and it allowed the impedance of the feedline and transmitter to match the antenna which meant the transmitter's energy went out the antenna in the form of radiation rather than just bouncing back to the transmi ...[text shortened]... e individual sections are just on the ground.

    It looks like your dad is a silent key. RIP.
    It was horizontal the antenna. He turned it by hand though and had a thing that locked it's position but it was mechanically moved. I can't remember the height but may be 30' or 40' max I remember him working different stations all over the world. He would receive these cards from the stations he worked. He had regulars too that he would chat with. I do remember that the system had to be matched or tuned as you said or as he said it could burn up the radio. I think it was a Yaesu but it was called a Tempo 1 or something like that. This was in the 1980's He bought a bunch of filtering stuff for the neighbors so he would not interfere with their T.V. LOL The guy across the street was pissed at my dad at first. He was into CB's too he would shoot skip but he said CB was getting crappy LOL

    Manny
  9. Standard member menace71
    Can't win a game of
    27 Jan '13 00:43
    Originally posted by sonhouse
    The extra thing sticking out was undoubtedly a 'gamma match', a section of antenna a few inches separated from the main antenna of a certain length and it allowed the impedance of the feedline and transmitter to match the antenna which meant the transmitter's energy went out the antenna in the form of radiation rather than just bouncing back to the transmi ...[text shortened]... e individual sections are just on the ground.

    It looks like your dad is a silent key. RIP.
    Keep it up



    Manny
  10. 30 Jan '13 20:01
    Originally posted by sonhouse
    http://phys.org/news/2013-01-ieee-80211ad-marketplace-wigig.html

    Mixed regular wifi signals with a 60 ghz frequency which allows 7 ghz data.

    To make an antenna for 60 ghz, a wavelength of 2.5 cm (one inch) a dipole would be two 1/4 inch sections, total width, 1/2 inch! A yagi at 0.2 wavelength element spacing would yield a 20 element antenna less than 4 inches long 10 cm!
    Does it stop you downloading viruses?
  11. Standard member menace71
    Can't win a game of
    05 Feb '13 03:10
    Originally posted by divegeester
    Does it stop you downloading viruses?
    the only way to prevent that is don't look at porn LOL




    Manny