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How many birds does it take to change the SWR? This is just a bit of fun looking at the very small but consistent changes that a group of swallows make to the Voltage Standing Wave Ratio (SWR) on my home made 20 metre antenna. It’s not a scientific experiment but the results were, not surprisingly, reasonably consistent as it’s a well know fact that you can use capacitive loading to alter the characteristics of an antenna. I did toy with the idea of arranging bird food at the ends of the elements were their capacitive effect would be more noticeable but I didn’t want to encourage the crows as if they decide to land on the beam en masse as I think they would do more damage than just transiently shift the SWR! Thanks for watching, if you’re interested in radio you’ll find some hopefully interesting items amongst my other videos, there’s a No19 set, a Spy Radio, some vintage radios and the construction of the 20 metre beam featured in this video. Kind Regards …Andy gw0jxm
Video Rating: 5 / 5

Antenna Tuner MFJ 941 C Follow us at www.twitter.com See Appalachia where N4USA is located www.floydfolks.org http 1-540-808-2880 All about Voltage Standing Wave Ratio SWR – en.wikipedia.org All the Tuner theory you want to know – en.wikipedia.org MFJ Wikipedia en.wikipedia.org Subscribe to my Channel – www.youtube.com How to use an antenna tuner www.hamuniverse.com David started at age 8 building Using or teaching about electronic devices – that was 65 years ago. It started with a crystal radio then ham license at 14 yrs tinyurl.com , Navy electronics at 17ys , Field Engineer at 21yrs tinyurl.com , teaching ‘Electronics for Scientist’ at Virginia Tech at 29yrs , Director of ‘Foundation for Amateur International Radio Service’ (FAIRS) at 52 yrs and at 73 he is still busy with electronics. Collector of historical Microcomputers tinyurl.com & along the way David has small collection of tuners. This tuner minimizes the VSWR between the transmitter & the tuner- it does not reduce or change the VSWR in the feed line to the antenna, that is done by matching the feed line impedance at the antenna end of feed line. Many antennas have a matching network to couple the feed line to the antenna. A poor antenna & feed line is not improved with the tuner only power transfer is maximized – this works for receive and transmit – using impedance matching is always useful for maximum power transfer. Video produced by the LCF Group, LCF Group consist of David Larsen KK4WW, Gaynell Larsen

linksys TNC 7DBI High Gain Antennas WRT54GS WAP54G BEFW11S4

Specifications:

Model Number: HGA7T
Connector: Reverse TNC
Peak Gain: 7dBi
FrequencyRange: 2.4GHz ~ 2.5GHz
Voltage Standing Wave Ratio (VSWR): 1.92 Max
Polarization: Linear Vertical
Direction: Omni-directional
Impedance: 50 Ohms Nominal
Dimensions (W x H x D): 11.22″ x 0.55″ (285 mm x 14 mm)
Unit Weight: 1.48 oz. (0.04 kg)
Compatible Linksys Products:
All WRT54G Routers except Version 8 (V8 – turn your router over to check the Version/V #)
WR

List Price: $ 13.00

Price: [wpramaprice asin=”B008UN3O48″]

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