VSWR

[RF-MAN]

i didn't use dummy load ........

i use site master with conector that joined with feeder .....

please say to me application of dummy load?????

[justdream]

"When you connect the dummy load all the energy absorb in the load. So if there is a fault you can see the reflected signal from it. But if you measure it with antenna connected, some energy reflected, and interfere with the reflected signal from the fault so if it's a weak signal you will not be able to see it. Using load in a sort of way increase the accuracy of your test"

[RF-MAN]

all your words are true but if antenna has problem and faulty maybe when we measure vswr by site master meet with above graph ???

i want know that antenna doesn't have problem???

feeder has problem or antenna ?


thanks a lot dear justdream

[qwertry]

Hi,

Based on my experience with VSWR measurements i can give you following advises:
1. Calibrate Anritsu Site Master together with Anritsu jumper before to start to measure.
2. Set valid RF band (GSM900 890.0–915.0/935.0–960.0), check that all RF component have same RF band, specially antenna, surge arestors and TMA.
3. If you have Xpol antenna, disconnect both ports from BTS/RBS.
4. Good feeder path together with antenna have VSWR below 1.5
5. Check DTF, select your feeder model from list in Site Master, set expected length, highest value (peek) must be in end of feeder line (in antenna).

From attached picture i can say that you have problem on feeder line close to BTS (may be RF connector), or you have surge arestor on feeder line and your Site Master settings are incorrect. Visit Anritsu web site there you will find very useful docs how to measure VSWR.

BR