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https://www.satsig.net/cgi-bin/yabb/YaBB.pl VSAT technology and installation >> iDirect Forum: hubs and terminals >> Symbol offset https://www.satsig.net/cgi-bin/yabb/YaBB.pl?num=1238483992 Message started by smlt_vsat on Mar 31^st, 2009 at 8:19am

Title: Symbol offset
Post by smlt_vsat on Mar 31^st, 2009 at 8:19am

Hi

What is symbol offset low means . i can see this condition in imoniotr

Title: Re: Symbol offset
Post by smlt_vsat on Mar 31^st, 2009 at 9:42am

Hello ALL

Whats the error tells "Symbol offset below " . is it something bad on RX side ? what we have to check ?

Title: Re: Symbol offset
Post by TDMAMike on Mar 31^st, 2009 at 12:14pm

Symbol offset (as observed thru iMonitor) is a timing correction value issued by the hub (to the remote) as the spacecraft moves in its station box. �It is normally a low number (around 5-10 up to 200-300). The hub literally monitors every burst from the remote and issues offsets to ensure that the remote remains centered in it�s time slot. �Adjustments are made (by the network) to the symbol offset every 20 seconds through the UCP (Uplink Control Process) in an effort to keep the burst centered. �For reference, SO = � Acquisition Aperture.

If you are getting SO warnings, there is a timing issue. �

Title: Re: Symbol offset
Post by smlt_vsat on Apr 6^th, 2009 at 4:41pm

if there is any warning , what we have to check ?

Title: Re: Symbol offset
Post by TDMAMike on Apr 6^th, 2009 at 5:04pm

How is it being observed? Single remote or several?

Title: Re: Symbol offset
Post by smlt_vsat on Apr 6^th, 2009 at 7:19pm

just single remote

Title: Re: Symbol offset
Post by TDMAMike on Apr 6^th, 2009 at 11:26pm

Do you have access to the TAC?

Title: Re: Symbol offset
Post by smlt_vsat on Apr 7^th, 2009 at 6:36pm

ya sure

Title: Re: Symbol offset
Post by TDMAMike on Apr 7^th, 2009 at 8:54pm

I would start with re-confirming the exact geo coordinates for the remotes location. �Since your other remotes are not reporting this warning, it appears to be isolated to the single node so re-confirming the Hubs geo coordinates is not needed. �Have the remote pinpoint its location in lat/long DMS. �Make sure it is as accurate as possible and add the digits to iBuilder (GEO TAB) and reset the remote (tcp)

M