rx path imbalance 3 DUG.

**auri_z** · 2012-07-05, 12:10 PM

dear all expert

i facing problem on E// RBS with use 3 DUG

there is alarm path imbalance on DUG 3 slave, VSWR at 1,05.
config on master 4/4/4 and slave1 4/4/4 and slave2 (DUG 3) 4/2 full config is 12/8/10.

what first step to identification this alarm or where wrong so alarm rise.

thank..

**Finetopix** · 2012-07-05 12:10 PM

**Abuelooorl** · 2012-07-05, 02:16 PM

Hi.

Restart the affected DUG. If possible do a power switching. Also check temperature in site.

Did you check the B feeder of the affected sector with an Anritsu or did you get that value from the OMT monitor?

Monitoring VSWR values only checks the A feeders in each DUG. Path imbalance is always VSWR limits on B feeder.

I would recheck that B feeder: connectors, antenna, TMA's and the feeder itself.

Good luck.

**auri_z** · 2012-07-05, 04:21 PM

i check with anritsu site master.nothing on value VSWR suspected because it's 1,05.
feeder,conn was check but nothing particular wrong.all on good condition.
is there possibly with config on site and BSC not match??

this alarm accur after ugrade from 8/8/8 to 12/8/10

**Abuelooorl** · 2012-07-06, 02:23 AM

Hi.

I think that if BTS config differs from the BSC's some TRX will be affected but the VSWR alarm is a diffferent case.

Did you check the VSWR threshold config? Maybe it's lower than the other RUG/RUS... Please also check combiners/diplexers.
And the last thing is the surge arrestors. We saw a pair of sites in which changing them the VSWR alarms dissapeared...

Try to swap the jumpers from A to B and vice-versa including the surge arrestor and rechek for the alarm. Or simply change the surge arrestor from B to A. If the alarm changes to A and can't startup then you've got the problem solved...

BR

**MAZ29** · 2012-07-07, 09:03 AM

connect OMT to DUG 3 and Then Read IDB and then Navigate to { Radio } Tab , Mark on all Check Boxes including {Fault} check box , then you will have the Faulty Connection Marked In RED color , ALSO , You May Have The Y-Link Cable Connected to the Wrong Port In DUG Cause if you have the Y-link Cable connected to the wrong port in both RUS ans DUG you will get that alarm.

**auri_z** · 2012-07-09, 09:22 PM

i will try check again what problem this site.
everything normal on site, but surge arrestor not yet i check.
i will check it's may be my problem will solved.