The Mud Pit > General
new CB and antenna
reg:
--- Quote from: HOT-ROD on February 16, 2008, 05:32:28 AM ---ah you know what, i have the radio crack version, and that may be why i didnt have to tune mine. DUH!!!
--- End quote ---
ok... look. the antenna has a screww at the top that wil lengthen or shorten the antenna. the antenna needs to be tuned to 1. what radio you have and 2. how long a cable you are running. the swr meter is a great tool that i wish i had. te onboard ones are nice.
Erik:
So far, everyone is close.
Radio doesn't matter. Length of cable doesn't matter. Whether the cable is coiled, rolled or in a mess, it doesn't matter. Length of antenna doesn't matter.
What does matter? A good ground for the radio. A good ground for the antenna. A good SWR.
SWR is Standing Wave Ratio. It the ratio of power that being transmitted versus the amount that is being reflected back towards the radio from a bad impedance match.
Theoretically, a ratio of 1:1 is ideal, but is unachievable. A SWR of 3:1 or less is what you are looking for. This is what we tried to achieve on the boat when transmitting via HF at 1000 Watts.
An external SWR meter is needed. The ones in the radio are ok, but not very reliable.
reg:
copied and pasted ;D
--- Quote ---Setting the SWR
All CB antennas are tunable. Antennas that have an easy, often mechanical, tuning device are referred to as a "tunable antenna". Accordingly, lots of people think the other antennas are not tunable and so they make no attempt to have the antenna tuned. This is a critical mistake.
Wire-wound antennas without mechanical tuners, that test electrically long (higher SWR on ch 40), can be tuned by removing wire from the top. Remove the antenna cap, remove one wrap of wire and cut it off. Recheck the SWR again. As long as the SWR is higher on channel 40 continue to cut. Do not cut more than one wrap at a time. If SWR testing indicates the antenna is electrically short (higher SWR on ch 1), the coils at the top of the antenna can be separated and spaced further apart or accessories that increase the physical length of the antennas (springs, quick disconnects) can be added.
Solid fiberglass antennas (straight or helical wire impregnated in fiberglass resins) that are electrically too long (higher SWR on ch 40) can be cut shorter with a hacksaw or grinder. Cut only 1/4 of on inch at the most at one time. If the SWR test on one of these antennas indicates that it is electrically short (higher SWR on ch 1), the addition of a spring or quick disconnect (or both) is the only way to correct for the short condition.
Base loaded antennas with wire whips have a set screw (or two) just below the area that the whip is inserted into the loading coil. By loosening up the set screw(s) you are able to slide the whip up or down as required. If the SWR is higher on ch 40 slide the whip down, If the SWR is higher on ch 1 raise the whip.
--- End quote ---
HOT-ROD:
ok way too much for me to understand.......
plug and play is my style.
moosin:
ive got a firestik with tunable end and it works fine for now just wanted to make sure i was getting everything out of it that i could. i knew i neede a meter just wasnt sure if anybody already had one thanx.
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