Hi JulianJulian said:OK, first post in this section.
Which CB Antenna to buy and how do you use an SWR Meter?
Thanks for any input
Wow you are getting good at this Jon, I could not described it any better.Jon Wildsmith said:Easy to explain in my head LC, not so easy out loud An over simplified explanation is that:
1) the ideal ground plane acts like a guide for radio waves. If you stick your antenna in the middle of a patch of dirt a good deal of the signal will be absorbed by the ground around the antenna because dirt is typicaly not a very good radio wave reflector / guide. A nice big sheet of steel on the other hand reflects / guides the radio wave energy that otherwise might have been absorbed so more of the signal gets into the clear.
2) objects close to the antenna affect its feed point impedance. You don't need to understand impedance in detail just know that the wrong impedance also affects the antenna's efficiency. A mobile antenna will have been designed to work sat in the middle of a decent ground plane, like a sheet of steel and have the right impedance when installed like that. If you don't put the antenna in a position with a good ground plane the impedance won't be what the designers intended and the antenna won't be as efficient as it should be.
A poor impedance match because of poor antenna positioning often shows up as the best SWR you can get still being quite high.
Technically the equipment has to have been certified for use on the CB frequencies to be legal and you won't find a certified amp What you could legaly do is get an amateur radio licence and be able to transmit up to 400 watts legaly on other frequenciesBattered and Blue said:Well, technically adding an amp isn't illegal as long as it doesn't boost output to over 4 watts -ok ok another ridiculous argument. Just that someone may have a 1 watt CB.
I've bought myself a Sirio HP 3000 too, and was told to start by cutting 2" off, if that is necessary why do they make them that long , why would Central Europe make any difference , I haven't used it yet as, like Manuel from Faulty Towers , I know notheeng about CB's and my CB set is buried in the dash and awkward to get at to connect an SWR meter.BIG clean GREEN said:OK so under advice I bought a sirio hp 3000, just fitted it and I'm not happy with the SWR readings, following the advice from 4x4 CB where I bought it from, I cut 2" off the top of the antenna, (due to it not being used in central europe) Advice please chaps Nick.