Advertisment: Broadband via satellite
Advertisment: Worldwide satellite services from Ground Control Company

www.satsig.net

Satellite Internet Forum.

Welcome, Guest.        Forum rules.
      Home            Login            Register          
Pages: 1

Any Broadsat Users here?

(Read 7798 times)
Ex Member
Ex Member




Jun 30th, 2008 at 2:29pm  
Hi all,
Broadsat (based in Pisa), switched to a different transponder on W3a Eutelsat last week, ( I switched to the new settings are per their instructions) and since then I have lost the signal.  I know that this is not unique problem that I have, as a friend 10 kilometers from me is on the same system and has the same problem.
The problem is they are not responding to emails or phone calls? My theory is they are either completely inundated with emails or they have ceased trading! Their website just shows the new transponder settings, no mention of major problems.
Just interested to know if anyone else is has experienced a loss of signal since the switch last Tuesday.
Back to top
 
 
IP Logged
 
Ex Member
Ex Member




Reply #1 - Jul 1st, 2008 at 3:46pm  
Just an update,
Broadsat obviously have a problem with the new transponder settings, I still have no signal but I found this (and a BIG thanks to Beyondsl for an explanation),

McD
Back to top
« Last Edit: Feb 19th, 2015 at 8:58pm by Admin1 »  
 
IP Logged
 
Ex Member
Ex Member




Reply #2 - Jul 18th, 2008 at 4:46pm  
Broadsat seemed to have rectified the above “fault” and all their subscribers have the service up and running again.

That is with the odd exception (5 subscribers to be precise if I am to believe their figures).  Unfortunately I, along with the only other subscriber to Broadsat that I know personally, who lives 10 kilometers from me further along the south coast of Cyprus are two of those subscribers who are unable to get a signal with new transponder settings.
 
Broadsat, have in all fairness offered to refund our subscription.  I/We would rather have the internet working.

Prior to 24th June my dish was pointing at Eutelsat W3A on frequency 10262000 symbol rate 27500 Horizontal Polarisation and I had an average Signal Level in excess of 80% and Signal Quality 100%.  (I have screenshots of before and after the changeover).  After the 24th June Broadsat/Eutelat only switched the transponder to W3C5, the only thing that changed was the frequency to 11303000. Now all I can get on the computer is a signal level of 38/50% and no signal quality.

My question is my dish hasn’t moved – I am assuming that neither has the satellite - so the only thing that has changed is the transponder.  So why no signal?  My house is about 4K from the coast flat and level, my friend 10k further east, again about 4-5k from the coast on a hill with a clear unobstructed seaview.  So no obstructions, and we are both well within the satellite footprint (we both have 1 meter dishes), and DVB card/box are still working

I would appreciate if anyone could offer a plausible/technical explanation on what has happened.

Sorry it’s a bit long winded but I tried to include as much information as possible I NEED HELP!!

McD
Back to top
« Last Edit: Feb 19th, 2015 at 8:58pm by Admin1 »  
 
IP Logged
 
Admin1
YaBB Admin
★★★★★
Offline



Posts: 1189
Reply #3 - Jul 18th, 2008 at 5:40pm  
I have not read the other details but my guesses as to plausible explanations:

1. Poor polarisation alignment.  With the old carrier there may have been only low level carrier(s) on the opposite polarisation.  With the new carrier there may be large carrier(s) on the opposite polarisation.   So a dish with poor polarisation setting may have worked fine at the old carrier frequency but not at the new, where you will be getting interference.

Fix the above by fine adjusting the polarisation.

2. Poor pointing/sidelobe/focus.   With the old carrier there may have been low level carriers on the same frequency and polarisation on the adjacent satellites - so no problem.   At the new frequency there may be high level carriers on the adjacent satellites - so if your pointing/sidelobes or focus are poor you will have interference.

Fix the above by a) re-pointing, possibly offsetting slightly one way to get the first null in the antenna pattern aimed at the interfering satellite b) checking dish rim flatness (<1.5mm gap in crossed fishing lines at Ku band) and c) checking dish assembly focus distance of feed to lower edge of dish.  The antenna pattern should have sharp nulls either side of the main beam which indicate it is in focus. A distorted dish due to heavy feed may have a remarkably large beamwidth and 'listen' to the adjacent satellites, as will an out of focus dish (e.g. HughesNet with the wrong slider focus position or side support struts in wrong holes).  The dish size needs to be suitable for the satellite spacing.  Small dishes need widely spaced satellites and it is not a good idea to have the first sidelobes aiming at the adjacent satellites.

Best regards, Eric.
Back to top
« Last Edit: Jul 18th, 2008 at 9:52pm by Admin1 »  
WWW  
IP Logged
 
Ex Member
Ex Member




Reply #4 - Jul 20th, 2008 at 1:08pm  
Eric,
Thanks for the reply, I have spent the last 2 days on the roof (I am using a Lacuna Mk2 satellite meter, and I don’t have a spectrum analyzer), still can’t find the right transponder.  In addition to trying to fine tune polarization (point 1), couldn’t get any improvement.  Regards points 2b).dish rim flatness it was about 2mm, and checked focus 2c) and it was OK.  Even went as far this morning of changing the dish to an older bigger one but still no joy and also replaced the single LNB with a Invacom twin LNB, and I still can’t get a signal on frequency 1130300.  The thing that puzzles me is that on frequency 11513000 I get a signal level of 70% with 100% quality.  So this is the transponder that I am locking onto.
Any suggestions?
Regards

McD
Back to top
 
 
IP Logged
 
Oasis Networks
Senior Member
★★★
Offline



Posts: 232
Reply #5 - Jul 20th, 2008 at 3:28pm  
Are you sure you put the right symbol rate?
Maybe it was altered as well?
Back to top
 

www.oasisnetworks.net - Oasis Networks - Online with you!
IP Logged
 
Eric Johnston
YaBB Moderator
★★★★★
Offline



Posts: 2109
Reply #6 - Jul 20th, 2008 at 4:17pm  
I guess the old frequency was 10762 MHz.

This is what I can see here using https://www.satsig.net/spectrums/satellite-spectrum.htm

Old wanted carrier below Horizontal nominal polarisation. W3A 607 10762 100
...

Vertical (potentially interfering) spectrum at old frequency below W3A 607 10762 100
...

New wanted carrier below  Horizontal nominal polarisation. W3A 607 10762 100
...

Vertical (potentially interfering) spectrum at new frequency below W3A 607 10762 100
...

From the above note that at the new frequency there is similar level traffic on the opposite polarisation, so setting up the polarisation accurately now matters.

Have you set your polarisation adjustment angle? Use this page https://www.satsig.net/maps/lat-long-finder.htm
The procedure is to set the nominal polarisation first. For Horizontal nominal polarisation the broad faces of the rectangular LNB waveguide will be on either side. Then apply the adjustment angle accurately.  Add 3.5 to the calculated result.  For W3A and Cyprus the adjustment required will be about 33.5 deg clockwise while facing towards the satellite.

Now that I have seen the old and new frequencies I note that they are far apart.  Using a 9.75 GHz LO LNB, the IF frequencies are 1012 MHz and 1553 MHz.  Another possible reason for the new frequency failing is that your cable has deteriorated due to moisture and that its attenuation increases rapidly with L band frequency.

Best regards, Eric.
Back to top
« Last Edit: Jul 20th, 2008 at 6:06pm by Eric Johnston »  
 
IP Logged
 
Eric Johnston
YaBB Moderator
★★★★★
Offline



Posts: 2109
Reply #7 - Jul 20th, 2008 at 4:44pm  
Test carrier below  Horizontal nominal polarisation. W3A 607 11513 100
...

Vertical (potentially interfering) spectrum at test frequency below W3A 607 11513 100
...

Looking at the test carrier at 11513 MHz there is cross pol traffic and if you are receivng that OK then your polarisation adjustment should not be the cause of the failure at 11303.

Here is yet another idea.

Satellite tuner automatic frequency control can normally cope with frequency errors of about +/- 1.5 MHz due to DRO type LNBs being off frequency.   Try setting 11302 or 11304 at the start frequency.

Best regards, Eric.
Back to top
« Last Edit: Jul 20th, 2008 at 6:08pm by Eric Johnston »  
 
IP Logged
 
Ex Member
Ex Member




Reply #8 - Jul 21st, 2008 at 9:51am  
Eric,
Thanks for all the information.  This morning I decided to go back to basics with the configuration (ie original dish and LNB).  Everything set up with the Lacuna.  Then I tried your last suggestion first (as it was the easiest!), I changed the frequency to 11302 – nothing - then tried 11304 and immediately I got a signal strength of 65-67% and signal quality of 100%, then I tried 11305 and the strength jumped to 69%?!?  So you/(I) seemed to have found the root of the problem.  Is the LNB at fault here? (I haven’t tried the Invacom twin with the new settings), or is it the satellite?

Regards

McD
Back to top
 
 
IP Logged
 
Eric Johnston
YaBB Moderator
★★★★★
Offline



Posts: 2109
Reply #9 - Jul 21st, 2008 at 4:36pm  
I would not say the LNB was faulty, rather that you have a DRO type LNB will a rather large frequency error.  DRO LNBs have errors up to +/- 2 MHz.  You can get better ones.  If does not matter much if the carriers are big, like 27.5 Msps and the tuners can sweep +/- 2 MHz.

For small SCPC carriers, DRO LNBs are hopeless as the freq error may easily make you miss the carrier or even tune to the wrong one.  You need PLL type LNBs for narrow SCPC or very clever modems (e.g Wegener DR-95) that will search across wrong carriers till they find the right one.  PLL LNBs are also necessary for phase noise reasons with low bit rate carriers.

Regarding your carrier on 11303 MHz I wonder if Eutelsat moved it slightly up, say 500 kHz, to reduce the interference effect when there was interference on the low side.  If so they may have forgotten to move it back.  Shifting a 27.5 Msps carrier by 0.5 MHz will affect only those few sites whose LNBs are already off frequency the wrong way by more than 1.5 MHz (say)

Some modems show frequency error, in terms of the stress in the AFC loop in the modem.  So if the satellite is accurate, the freq error = the LNB error.  It varies with temperature during the day.

My LNB LO is typically 800 kHz low and the L band frequencies in the cable are in error about 800 kHz high.

Best regards, Eric.  
Back to top
« Last Edit: Jul 22nd, 2008 at 10:06am by Eric Johnston »  
 
IP Logged
 
Ex Member
Ex Member




Reply #10 - Jul 22nd, 2008 at 6:37pm  
Eric/All

I passed all the information to Broadsat yesterday and their response was that I quote:
“The same problem had been reported by a few customers in Cyprus and Ireland.
Some of them were able to solve it by fine tuning their dish or by replacing their LNB.  Unfortunately, we are unable to help you any further.”

Customer service/satisfaction not exactly top of their priority!  

I tried the Invacom Twin LNB today and managed to get a signal on the 11303, (but oddly couldn’t get a signal on 11304-5) but couldn’t get it to lock, or a signal strength past 55%.  I do not want to go and spend more money on another new LNB if it is still going to give problems.  I am about to give up - 3-4 hours a day on a roof in temperatures of 35 degrees plus takes its toll!

It would appear I will be looking for a new one-way Internet provider, as Broadsat doesn’t seem  to want to know.  I won’t be recommending them on this forum again!  Then again - Maybe it’s me? I retired from Ireland to here (coincidence)!!

Thanks for the help

McD
Back to top
« Last Edit: Jul 23rd, 2008 at 11:20am by Laurie »  
 
IP Logged
 
Eric Johnston
YaBB Moderator
★★★★★
Offline



Posts: 2109
Reply #11 - Jul 22nd, 2008 at 6:51pm  
The specification for the twin Invacom LNB is here:
https://www.invacom.com/

I note that with temperature the stability is +/- 3 MHz.

So try 11300 11301 11302 11303 11304 11305 11306
etc till it works.  

Test to find the best frequency in cold night and hot day and then choose the average frequency, so the receiver automatic frequency control can swing either way.

35 deg C ambient probably means far higher temperature for the LNB with the sun shining on it.

Try a new cable also.  The very hot day followed by cold night sucks cold damp air into the cable at night and moisture progressively accumulates inside.  It is quite common for an aluminium sheath film to turn to white dust in such circumstances.  Sealing the F connectors is important even in what appear to be hot dry places.

Best regards, Eric.
Back to top
« Last Edit: Feb 19th, 2015 at 8:57pm by Admin1 »  
 
IP Logged
 
Ex Member
Ex Member




Reply #12 - Jul 24th, 2008 at 4:58pm  
Eric/All

Update!!

Reference the frequency testing hot days cold nights NO CHANCE here at this time of the year, hot hot and slightly less hot at night!! On the roof temp in excess of 40 degrees during the day and you are lucky if it drops below about 30 at night (flat roof!!).  I do have all my connectors well sealed so not a problem there. 

As I said in my last post I had “given up” and wrote to Broadsat requesting a refund etc etc.  Which they kindly obliged to do stating that at some time in the future they would be switching from Transponder C5 to an ‘A” transponder, and that they would send me an email/flyer when the new transponder comes on line.

Was out this morning and came home after lunch and an email from Broadsat stating that transponder A12 was up and running with the settings Frequency 10.928 SR 27.5 Polarization Vertical FEC 3/4. 

I put in the new settings and immediately the signal strength and quality were at maximum!!

So problem solved (for the moment).  The mysteries of Satellite communications??

Many thanks for all your help, patience, time and contributions over the last 3-4 weeks.

McD
Back to top
 
 
IP Logged
 
Pages: 1