G-Way Microwave / G-Wave PCSHW70A 사용자 설명서

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DIAGNOSTICS GUIDE 
 
The Mini-BDA provides long term, care-free operation and requires no periodic 
maintenance. There are no user-serviceable components inside the Mini-BDA.  
 
This section covers possible problems that may be related to the installation or 
operating environment. 
 
a. Gain Reduction 
Possible causes: Bad RF cables and RF connections to antennas, Damaged 
antennas. 
 
b. Excessive Intermodulation or Spurious 
Possible causes: 
Amplifier oscillation caused by insufficient isolation. The isolation between two 
antennas is given by the equation: 
Isolation = 92.5 + 20 Log (F x D) – Gt – Gr 
Where: 
F = frequency (GHz) 
D = separation (Km) 
Gt = transmit antenna gain (in the direction of the receive antenna). 
Gr = receive antenna gain (in the direction of the transmit antenna). 
 
For the SMR frequencies, the antenna isolation at 100 m separation is about 71 dB 
for omni-directional antennas (0 dB gain). To increase isolation, the antennas should 
have higher directivity and must be pointed away from each other. 
 
c. Occasional Drop-out of some Channels 
Possible causes: One channel with very strong power dominates the RF 
output of the amplifier. 
 
 
 
 
 
 
 
15 Ron’s Edge Road 
Springfield, New Jersey 07081 
Tel. 201-343-3140   Fax 201-343-6390 
sales@gwaverf.com
 
www.gwaverf.com 
 
 
 
 
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