Big Hair's CB Base Antennas:
Antenna Comparison Tool- Click on a specific CB Base Antenna on the left side of screen, to learn more
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Antennas modeled, using precise NEC Antenna modeling:
From my testing range, all of my CB base antennas beat both an Antron and IMAX 2000 and other 11
meter CB antennas in performance, (even the 0db claimed gain of my vertical dipole). You have to realize
that antenna manufactures claim ridiculous gain figures, just to sell antennas, without telling you what
they are comparing those gain figures to.. Meaning, if they claim their 1/2 wavelength 18' lossy CB base
antennas claim a whooping 10db of gain (which is impossible for a 1/2 wave or even a 5/8th wave
antenna), you have to question whether that gain in reference to a dummy load, or a "true" reference
antenna?? This is the reason I am very "conservative" with my gain numbers, as it represents "true" gain,
over typical 5/8 wave antennas.
If you take the time to closely review the specs, you'll notice that no antenna is perfect, and they all have
their pros and cons, however once you get more advanced with antennas and the more you manipulate
them to gain something, it often happens that you'll also lose something in return. For example, its
obvious that the collinear has the highest low angle gain, but it also has the "narrowest" beamwidth.
Another example, is that 1/2 wave CB base antennas when connected at the bottom have a wide SWR
bandwidth and some decent gain, however it also has a very high impedance, and the only "efficient" way
to match its impedance from 3,000 ohms to 50 ohms is to use whats known as the parallel optimum
matching technique where "both" a shunt inductor and capacitor are involved. If only an inductor were
used for matching this antenna, its Q-factor would be lowered, and its efficiency would be degraded. A
capacitor often has over a 1200 Q-factor (the average inductor has only a 200 Q-factor), however its nearly
impossible to find an affordable transmitting capacitor that will handle over 5kw of power. However, for
most purposes and for most C.B.ers, I think 5kw is probably enough. Where a capacitor isn't needed, I
can obviously make the other antennas handle 30kw plus, as I beef all my CB Antennas up with heavy
duty gauged conductors/inductors.
The Collinear CB Antenna is actually two x 5/8 wave antennas vertically stacked and phased together, to
double their low takeoff angle gain. This is the reason the antenna is nearly 50' tall!
meter CB antennas in performance, (even the 0db claimed gain of my vertical dipole). You have to realize
that antenna manufactures claim ridiculous gain figures, just to sell antennas, without telling you what
they are comparing those gain figures to.. Meaning, if they claim their 1/2 wavelength 18' lossy CB base
antennas claim a whooping 10db of gain (which is impossible for a 1/2 wave or even a 5/8th wave
antenna), you have to question whether that gain in reference to a dummy load, or a "true" reference
antenna?? This is the reason I am very "conservative" with my gain numbers, as it represents "true" gain,
over typical 5/8 wave antennas.
If you take the time to closely review the specs, you'll notice that no antenna is perfect, and they all have
their pros and cons, however once you get more advanced with antennas and the more you manipulate
them to gain something, it often happens that you'll also lose something in return. For example, its
obvious that the collinear has the highest low angle gain, but it also has the "narrowest" beamwidth.
Another example, is that 1/2 wave CB base antennas when connected at the bottom have a wide SWR
bandwidth and some decent gain, however it also has a very high impedance, and the only "efficient" way
to match its impedance from 3,000 ohms to 50 ohms is to use whats known as the parallel optimum
matching technique where "both" a shunt inductor and capacitor are involved. If only an inductor were
used for matching this antenna, its Q-factor would be lowered, and its efficiency would be degraded. A
capacitor often has over a 1200 Q-factor (the average inductor has only a 200 Q-factor), however its nearly
impossible to find an affordable transmitting capacitor that will handle over 5kw of power. However, for
most purposes and for most C.B.ers, I think 5kw is probably enough. Where a capacitor isn't needed, I
can obviously make the other antennas handle 30kw plus, as I beef all my CB Antennas up with heavy
duty gauged conductors/inductors.
The Collinear CB Antenna is actually two x 5/8 wave antennas vertically stacked and phased together, to
double their low takeoff angle gain. This is the reason the antenna is nearly 50' tall!
Click here to see a Big Hair and IMAX 2000 Antenna Comparison:
CB Base Antennas
Click Photos below to see full page:
Our high gain 50 foot
collinear CB fiberglass
antenna (the only
omni-directional CB
antenna that rivals
beam performance!
collinear CB fiberglass
antenna (the only
omni-directional CB
antenna that rivals
beam performance!
You cannot simply make an antenna longer and longer to improve its low angle gain. A 5/8 wave is about as long
as you can make an element (or .64 wavelength to be more accurate), without losing antenna performance.
Typically for antennas this translates approx to 22' 6" at 27Mhz. Many CB base antennas are 24' in physical length,
because the bottom 18" or so is actually below the coil, and this bottom below the coil is usually an aluminum
coupler that doubles as both as a mast mounting assembly, and housing the coax that connects to the coil used for
matching the antenna.
This is the reason the collinear base antennas have such high low angle gain, is because they are not electrically a
50' long antenna, but rather two 5/8 wave CB base antennas stacked on top of each other.. There is actually a
middle phasing section, the brings both 5/8 wave elements in phase electrically.. This both doubles the collinear's
gain and improves the antennas pattern with an improved low angle of radiation.
Click here to learn more info about CB Antennas.
as you can make an element (or .64 wavelength to be more accurate), without losing antenna performance.
Typically for antennas this translates approx to 22' 6" at 27Mhz. Many CB base antennas are 24' in physical length,
because the bottom 18" or so is actually below the coil, and this bottom below the coil is usually an aluminum
coupler that doubles as both as a mast mounting assembly, and housing the coax that connects to the coil used for
matching the antenna.
This is the reason the collinear base antennas have such high low angle gain, is because they are not electrically a
50' long antenna, but rather two 5/8 wave CB base antennas stacked on top of each other.. There is actually a
middle phasing section, the brings both 5/8 wave elements in phase electrically.. This both doubles the collinear's
gain and improves the antennas pattern with an improved low angle of radiation.
Click here to learn more info about CB Antennas.
Go back to Big Hair's CB Antennas Homepage.
5/8 wave tree mounted
Big Hair's 1/2 wave
"over" a true quarter
wave CB Base Antenna
"over" a true quarter
wave CB Base Antenna
Big Hair's big mama, 50'
Collinear Antenna- a 5/8
wave over another 5/8
wave, followed by a
quarterwave ground
plane kit
Collinear Antenna- a 5/8
wave over another 5/8
wave, followed by a
quarterwave ground
plane kit
known as 600 in skip
land, and "Broken
Crank" by the ladies)
"Flag Pole" Antenna
land, and "Broken
Crank" by the ladies)
"Flag Pole" Antenna
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