- Nov 19, 2010
- Reaction score
WELCOME TO MELODYWORLD .
WIFI QUALITY PRODUCTS
AT SUPER VALUE !!
BRAND NEW MODEL NOV 2010 !!
AMY YAGI 18Dbi VERSION !!
(Pre-Order item ..delivery approx 2-5 days)
Brand: AMY brand
Model No.: AMY-2400-18
BESST PRICE = RM 85
Poslaju RM 5
= Rm 90 incl poslaju
Delivery : 2-5 days approx.
Brief AMY background:
AMY is a technology company with R&D department and manufacturing arm based in China. The company claimed that producing a "true 18dbi yagi" requires 3 fold times that being needed to produce a tradisional 16dbi yagi, therefore the supply of 18dbi yagi won't be as much as 16dbi yagi in same production time frame.
Reason (1) of getting AMY product: AMY stessed that they DO NOT simply add 2 director to a tradisional 16dbi yagi and claim it having 18dbi without going through R&D and complete tuning process. Some china factories's 18dbi yagi are not real 18dbi!!!
18dbi Yagi Directional Antenna ~ also brand AMY, NOT TDJ!
Insist AMY® = Insist on Quality Antenna (unless don concerned quality...)
Reason (2) of getting AMY product: just browse following AMY quality finished good pictures:
this is brand AMY yagi antenna (AMY-2400-18), NOT those TDJ brand (model no. TDJ-xxx).
They are different in quality and AMY product cost higher! Pls distinguish different stocks, don't compare price directly..
Applications: attach antenna to wifi devices through coaxial cable, use the bundled clips to clip and hold the antenna firm to someplace.
Q: many users ask for longer antenna's coaxial cable such as 5 meter....
A: Best use with 1 meter RG58 come along from manufacturer to minimise cable-length signal-loss problem.
Bcoz 1 meter cable RG58 would cause ~0.7dbi loss in the transmission.
If using 5 meter RG58, means 0.7dbi x5 = 3.5dbi loss!
18dbi panel + 5 meter RG58 = 18dbi - 3.5dbi = 14.5dbi remaining! this is serious!
Why buy high gain antenna but loss in cable transmission? not worth.
Recommended alternative ways to do 'extension':
a) if using with usb wifi adapter, get 5 meter usb extension cable, that not cause dbi loss.
b) if using with router/ap, get power extension or POE, that not cause dbi loss.
If after trying above methods, still absolutely necessary to extend antenna's coaxial cable:
a) for 4 meter or below, still can use RG58 cable type (if u can compromise).
b) for 5 meter to 10 meter, pls use high grade low loss cable LLC200 type.
c) for over 10 meter, pls spend money to get highest grade low loss cable LLC400 type.
Reason (3) of getting AMY product: Critical feature by AMY yagi:
adjustable up/down direction ~ this is most critical part of using yagi antenna which got narrow direction beamwidth,
one need flexbility to point sharply by adjusting direction up/down and left/right.
Cable: RG-58 1 meter
Includes: 2 clips
Frequency Range–MHz 2400～2483
Horizontal Beamwidth -° 18
Vertical Beamwidth -° 18
F/B ratio-dB ≥18
Input Impedance -Ω 50
Polarization Vertical or Horizontal
Maximum Power -W 100
Mast Diameter-mm Ф40～50
1, 30 degrees vertically adjustable fixture, scanning more wider zone to increase signal strength with quite a bit
2, Good performance on electromagnetic shielding, a more low-loss coaxial cable
3, Utilize more precise manufacture process
1. Some of cooperation partners: Why not do a longer line, according to industry data, 50-3 lines: Copper containing SYV-50-3/RG58U
Line, 2.4g frequency of more than 0.7db attenuation per meter, is not as long as possible, rational point of people see at a glance.
2. Gain Description:
The gain is that the so-called line loss excluding the gain, the value from the test chamber, non-users with the use of "Network
Stumbler "" WirelessMon "to test the accuracy, antenna test requires no interference, no refraction of the signal to test out. Feeder longer
Greater attenuation for the project users, can not be tolerated even if 0.5db attenuation, attenuation means that shorten the distance firing!
3. Through the wall it can improve?
In fact, each block of cement brick general attenuation of signal is 10 ~ 15dbm, if it is reinforced concrete structure, the wall did not approach, equal to the total
Shield! If there are signals that the environment can only be understood as the reflection of electromagnetic waves, so do not expect the antenna a few walls for you to wear, it is of extreme
Real! If your device is 100MW, converted into dbm value is 20dbm, then the value is 16db with the antenna, then, is equivalent to 36dbm, ideal point
, This antenna with the device can be worn 3 block walls, the more popular interpretation of it.
Yagi Antenna Scope of application:
1. Point to Point Network Engineering (2km ~ 3km)
2.2.4g use of terminal equipment, such as wireless LAN and ap
3. Rural area wireless coverage receiver antenna
4.2.4g wireless location devices