ON3JT

First I tried to build a Cobwebb antenna. It is a small antenna and rather easy to build. I used cheap fishing rods, costing 4 to 5 euro each, from a known sports hardware shop. The funny thing was when I asked the sales person if the rods contain carbon fibers he mentioned that I’m not the first asking. He says = “Some people use them to make antennas…”. Big smile when I replied to do the same. Bought speakerwire and started cutting and soldering. Finally the first dipole was attached to the big cross. Added in total 4 dipoles when I wanted to test it. It was a small disapointment. Only 400 kHz usable bandwidth on 10m. The 12m and 17m were usable. But 15m also lacked the necessary bandwidth. That, the mechanical instability and difficulties (more…)

My homebrew HF multiband antenna tipped over during a storm in december 2007. Not a real surprise because the mount was too small to handle the antenna, despite the weight of 8 concrete tiles. I remember that during that evening I was listening to some PSK31 signals on 20m and suddenly they disappeared. A quick SWR check learned me that the antenna was no longer in a vertical position.

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A cantenna is a directional waveguide antenna for long-range Wi-Fi used to increase the range of (or snoop on) a wireless network. Although the original design was based on a Pringles potato chip can, a cantenna can be made from various cans/bottles. These include antennas on both the ground and antennas heightened by means of a pole. While cantennas are useful for extending a wireless local area network (WLAN), the tiny design makes them ideal for mobile applications such as wardriving. The design of the cantenna is so simple that it is often the first antenna WiFi experimenters learn to build.
Retrieved from “http://en.wikipedia.org/wiki/Cantenna”

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I bought my Diamond X200n antenna on a local ham fleamarket in october 2006. It was brand new and never used before. The antenna was mounted on the first of august.
There is about 21m of H500 coax between the transceiver and the antenna. The antenna performs well on 70cm with a very low SWR curve. On 2m however the SWR is not what I expected.
On 146.000 MHz the SWR is 2,3:1 dropping to 1,8:1 on 144.000 MHz. That could be better. My neighbour and amateur ON5NV has the same antenna, so we replaced mine to see if the problem still occurs. It may be the connector or something with the coax.
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