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EXTEND RANGE WITH EXTERNAL ANTENNA
All cards in our eBay store have internal antennas. External antennas will extend the range
Most wireless cards have internal antennas, but these are adequate just for short links: i.e., a few hundred feet, with no obstructions. The addition of an external antenna will boost the range and signal strength very significantly. The range increase is due in part to the fact that external antennas stand upright, while internal antennas in wireless cards lay horizontal. A 7 dBi antenna will increase the gain of a wireless card, typically by a multiple of 3x or 4x (as compared to the gain of the internal antenna of a wireless PCMCIA card for a laptop PC).
Gain of an antenna is a measure of its enhancement of signal strength: Gain is measured by the dBi rating.
Gain of an antenna is a measure of its enhancement of signal strength: Gain is measured by the dBi rating.
Calculating Gain from addition of an antenna: “Rules of 3s and 10s:”
 “3 dB rule": For every 3 dB increase in level, the power is doubled. For every 3 dB decrease, the power is cut in half.
“10 dB rule": Every 10 dB increase in level results in 10 times the power, and every 10 dB decrease in level results in 1/10 the power.
Signal loss in cable: If a cable connects your device to the antenna, take signal-loss in the cable into consideration: See section below. |
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See case study/"how-to" network diagram, photos of network using this booster for large property with outbuildings. Includes equipment list links. | |
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Antennas generally have greater coverage at the expense of range, and greater range at the expense of width of coverage area ("half-power beam width"). Therefore, omni- directional antennas, which radiate the beam in all directions (on a horizontal plane) generally have gains no higher than 12dBi, while directional antennas can have gains up to 30dBi. As a general rule of thumb: The higher the gain, the narrower the beam width (coverage area).
Range:
14dBi antenna:
Range up to eight miles, at 11Mbps. Range is longer at lower transmission speeds such as 1, 2 or 5Mbps.
24dBi antenna: A point-to-point link using two 24dBi antennas pointed at each other, could effectively transmit/receive signal over a distance of 18 miles.
802.11b & g network gear automatically adjusts the rate according to distance / signal quality so that a lower transmission speeds such as 1, 2 or 5Mbps may be selected in long-distance link situations or if the signal is not strong for other reasons.
Half-power beam width is the specification of the antenna's coverage area. It is measured relative to the points at which the antenna's radiation drops to half its peak value.
Directional Antenna Types
Sectoral Antennas
Boost link quality by facing sectoral / directional antenna in direction of signal traffic. Concentration of radiation pattern (signal-strength) in a directional/180-degree pattern provides much better link quality than an omni-directional (360-degree) pattern.
Directional signal traffic situations:
- Access point antenna: To reach clients in a 180-degree pattern (i.e., a room)
- Stationary client/card: Face the antenna toward the access point.
Important note regarding signal loss in antenna cables: It is best to have the shortest cable that will serve your needs, since a small amount of signal strength is lost in the antenna cable. This loss amounts to 1.28dBi per meter. Antennas in our eBay store have cable types LMR100A and LMR200 (depending on length of cable), which is low-loss cable of much higher quality than the more common pigtail cables for small antennas, which are RG174. The higher quality of the cable of this antenna translates into lower loss / better performance.
Important note regarding threaded vs. non-threaded connectors:
Connector types with threaded connectors: RP-SMA, SMA, RP-TNC and N have threads that enable adapters to connectors of all types, as well as extension cables.
We offer four lengths of RP-SMA extension cables and an RP-TNC extension cable (3 meters). These adapters and extension cables are linked within the listings of antennas with RP-SMA & SMA connectors. The use of a threaded RP-SMA or SMA connector with adapter protects small jacks & connectors |
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ANTENNA SELECTION MATRIX
The following table includes only about half of our antenna offerings: This table is from the 2005 version of this page; the links are kept updated and all of the antennas in the table are in stock, but we now have many more antenna types to choose from:
Please see our ANTENNA CATEGORY which has over 16 sub-categories and is a better way to find the right antenna, for most buyers. Each antenna listing is in two sub-categories based on antenna type and connector type. |
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ANTENNA SELECTION MATRIX
In order of connector type. |
Connector
Type |
Compatible cards |
Cable Length |
Extension
cables |
Price |
Direction
Type |
Jack
Protection
(threads) |
dBi
Signal
strength |
802.11
modes |
Stock in: |
|
Magnetic mount: Car-top, boat, metal surfaces |
MC |
Orinoco & others |
2 meters |
No |
$12.99 |
Omni |
No |
7dBi |
B&G |
US, UK, Canada |
| Magnetic mount: Car-top, boat, metal surfaces |
MC |
Orinoco & others |
3 meters |
No |
$14.99 |
Omni |
No |
7dBi |
B&G |
US, UK, Canada |
|
Magnetic mount: Car-top, boat, metal surfaces
Recommended for jack protection |
MC |
Orinoco & others |
1.5 meters |
1M, 2M, 3M, 6M |
$19.99 |
Omni |
Yes |
7dBi |
B&G |
US, UK, Canada |
| Magnetic mount: Car-top, boat, metal surfaces |
MMCX |
Senao, Ubiquiti Engenius, Cisco others |
2 meters |
No |
$13.99 |
Omni |
No |
7dBi |
B&G |
US, UK, Canada |
|
Magnetic mount: Car-top, boat, metal surfaces
Recommended for jack protection |
MMCX |
Senao, Ubiquiti Engenius, Cisco others |
1.5 meters |
1M, 2M, 3M, 6M |
$20.99 |
Omni |
Yes |
7dBi |
B&G |
US, UK, Canada |
|
Mobile, very portable low-profile: Snaps into card. Easily bring in laptop/PDA case for use anywhere |
MMCX |
Senao, Ubiquiti Engenius, Cisco others |
No cable needed |
No |
$4.99 |
Omni |
Yes |
1.5dBi |
B&G |
US, UK, Canada |
| Magnetic mount: Car-top, boat, metal surfaces |
RP-MMCX |
SMC, Zcomaz, Demarc, others |
2 meters |
No |
$13.99 |
Omni |
No |
7dBi |
B&G |
US, UK, Canada |
|
Magnetic mount: Car-top, boat, metal surfaces
Recommended for jack protection |
RP-MMCX |
SMC, Zcomaz, Demarc, others |
1.5 meters |
1M, 2M, 3M, 6M |
$18.99 |
Omni |
Yes |
7dBi |
B&G |
US, UK, Canada |
| Mobile, very portable low-profile: Snaps into card. Easily bring in laptop/PDA case for use anywhere |
RP-MMCX |
SMC, Zcomaz, Demarc, others |
No cable needed |
No |
$4.99 |
Omni |
Yes |
1.5dBi |
B&G |
US, UK, Canada |
| Magnetic mount: Car-top, boat, metal surfaces |
RP-SMA
male |
PCI cards:
See list |
1.5 meters |
1M, 2M, 3M, 6M |
$13.99 |
Omni |
Yes |
7dBi |
B&G |
US, UK, Canada |
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Sectoral, wall-mount directional panel, indoor/outdoor. Adapters to all connectors linked within listing. |
RP-SMA
male |
Adapters to all within listing |
15 CM |
1M, 2M, 3M, 6M |
$7.99 |
Sectoral/
Directional |
Yes |
4dBi |
B&G |
US, UK, Canada |
| Magnetic mount: Car-top, boat, metal surfaces |
RP-TNC female |
LinkSys & Cisco WAP
See list |
1.5 meters |
3M |
$13.99 |
Omni |
Yes |
7dBi |
B&G |
US, UK, Canada |
|
Desktop sectoral: Semi-directional
Stands upright on any smooth surface |
RP-TNC female |
LinkSys & Cisco WAP
See list |
1.5 meters |
3M |
$19.99 |
Sectoral/
Directional |
Yes |
6dBi |
B&G |
US, UK, Canada |
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Sectoral, wall-mount: Swivel to aim directionally
Semi-directional, indoor/outdoor. Low shipping cost. |
SMA female |
See list |
Sold separately |
1M, 2M, 3M, 6M |
$27.99 |
Sectoral/
Directional |
Yes |
10dBi |
B&G |
US, UK, Canada |
|
Sectoral, wall-mount or pole-mount with swivel
Semi-directional, indoor/outdoor |
N female |
See list |
Sold separately |
1M, 2M, 3M, 6M |
$34.99 |
Sectoral/
Directional |
Yes |
12.5dBi |
B&G |
US, UK, Canada | |
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WIFI CARDS * CABLES * ADAPTERS
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Copyright 2004-2008 Data Alliance llc. This page, the contents, website and all listings are protected by copyright law, international treaties, and eBay policies.
Data Alliance llc is registered in Arizona, USA. | |
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