Help with Tooway install

Hi
Encouraged by Cambrian's success with his Tooway self-install, I took the opportunity to purchase the Tooway hardware from a previous Tariam customer.
The dish, TRIA, Modem & miles of coax cable arrived from the vendor and I set about installing it on the front of the house.
I then signed up for the basic account with Bentley Walker. connected it all up but alas no satellite lock. I telephoned BW and spoke to a technician who informed me that I needed a better C/N ratio (I only got about 9.3db). At this point I decided to put the dish on a chimney mast well clear of any obstacles . I borrowed a 'cherry picker' from a friend and duly sited and aligned the dish about 500mm above an Astra 2D dish. Using a Promax Prolink-2 spectrum analyzer, these are the results at the dish.

C/N Referenced:   10.4 dB

Video Carrier
Frequency:      1377.75 MHz
Level:            73.9  dBuV

Noise
Frequency:      1443.5 MHz
Power:            63.5 dBuV
Channel BW:       30.0 MHz

These levels are attenuated aprox 6dBuV by the coax down lead to the modem location.

The modem acquires a signal but alas still no lock.

Extract of the event log:-
THU JAN 01 01:03:49 1970      DS Scan: 1375.636353 [MHz]
THU JAN 01 01:03:42 1970      DS Scan: 1380.000000 [MHz]
THU JAN 01 01:03:40 1970      DS NAPA: Success
THU JAN 01 01:03:39 1970      DS Acquire: 1375.574951 [MHz], 30.00 [Msps], 10.00 [dB], MR
THU JAN 01 01:03:33 1970      DS Scan: 1375.574951 [MHz]
THU JAN 01 01:03:26 1970      DS Scan: 1370.000000 [MHz]
THU JAN 01 01:03:06 1970      US Scan: 2144.399902 [MHz], Channel 5
THU JAN 01 01:02:11 1970      US Scan: 2140.800049 [MHz], Channel 8
THU JAN 01 01:01:39 1970      US Scan: 2148.400146 [MHz], Channel 3
THU JAN 01 01:01:37 1970      DS NAPA: Success
THU JAN 01 01:01:36 1970      DS Acquire: 1375.625488 [MHz], 30.00 [Msps], 11.00 [dB], MR
THU JAN 01 01:01:30 1970      DS Scan: 1375.625488 [MHz]
THU JAN 01 01:01:23 1970      DS Scan: 1360.000000 [MHz]
THU JAN 01 01:01:18 1970      DS Scan: 1350.000000 [MHz]
THU JAN 01 01:01:13 1970      DS Scan: 1340.000000 [MHz]
THU JAN 01 01:01:08 1970      DS Scan: 1330.000000 [MHz]

Do I need to hunt around for a different location or is there a possible fault in the TRIA or modem.

Any advise will be most appreciated.
Regards
Wil

I am located in North Wales at approx latitude = 52.9, longitude = -4.4
My initial settings were thus
Dish elevation= 27.4
Azimuth= 163.5 M
Polarisation= -12.7+3.5=-9.2
There seems to have been some debate about the +3.5 degrees added to the skew; I went with it because of ‘Figure 8 : Polarisation Angle Chart for the 13°East Orbital’ in Eutelsat’s document ‘Annex A The Hot Bird™ Satellite’ https://www.eutelsat.com/satellites/pdf/tvservices/annex_a_HOTBIRD_sat_sys.pdf
The assembly seemed visually ok when I installed it. Unfortunately I do not have access to the dish until early next week to double check the physical condition of the dish & TRIA.
In the meantime I have uploaded a photo of the spectrum analyser

taken at the indoor end of the 25m coax which is quite similar to the one published by El Molino :-
https://www.europe-satellite.com/EMS/pdf_files/sat_info/hotbird6_sa_info01.pdf


BW only required the MAC address of the modem, which they received when I subscribed to the basic package.
Many thanks for all your help and advice.
Wil

Hi Wil,

I am some way south of you but my settings are:-
elevation 31.5deg. (I believe the scale is not quite right on the dish). Skew is 80.7 deg and azimuth set by compass at around 163/164 deg.

It is VERY misty, lots of water droplets in the air, and it is raining hard also but my system is working fairly well this morning.

Hope this helps.

Best regards,

Tony

I've spoken with Scott at Bentley Walker about your site.
You need to call him on 023 9231 1118 to activate your site.

Best regards, Eric.

Wil, Tony

Site activation:
BW indicated that the modem was from previous service provider where it had been de-registered.  A new activation configuration and process was needed, that maybe involved getting Skylogic to transfer the modem in their database and a new customer PIN being issued.

Polarisation:
If there is a carrier on the opposite polarisation then some small polarisation movement, say 10 deg, will make a noticable difference.

If there is no cross-pol carrier then you will need an error of +/- 45 deg to get a 3 dB reduction.  If you can measure the angle at these exact -3.0 dB points then you can half the angle between them.

If there is no cross-pol carrier and you have a spectrum analyser and turn the polarisation boldly approx 90 deg the wrong way you will find the narrow sharp null where the wanted carrier disappears.  It is fairly easy to identify either side of this deep null and note the centre angle. Then turn the system exactly 90 deg for the optimum angle.

Attempting to peak up the quality by small adjustments of polarisation, in the absence of a steady high power cross-pol interferer, is not practically possible.

I am anxious to verify the polarisation angle calculation on page Tooway satellite antenna pointing and maybe even resolve if the +3.5 deg offset applies to the Ka band beam as well as Ku band beams on Hotbird.

Some people seem to agree with the calculator, others get peaked up results at different angles. No idea why as the downlink beam is a single all-Europe coverage.

My understanding is that rotating the dish anticlockwise, as for sites in the UK aimed at 13 deg east orbit position, increases the scale reading from 90 (i.e. direction towards 100).  Such polarisation adjustments are negative, like -10 deg. Anticlockwise as seen facing towards the satellite.  

Best regards, Eric.

We are all trying to help you.

I think your site receive quality is fine with 11dB C/N.   I've seen documents refering to sites with minimum of C/N=5 dB..

My opinion is that the skew scale should be about 100, i.e. about 10 deg anticlockwise from the start position. Anticlockwise as viewed with you behind the dish and facing towards the satellite in the sky.

Please tell us how you get on.  If BW need to get Skylogic to do something don't expect instant results !  Reconfiguring a previously blocked site with a different service provider and getting it restarted is a bit more complicated than setting up a new out-of-the-box modem.

Best regards, Eric.

Quote:

There is just one broad downlink beam for all Europe.  You are measuring the downlink signal.  All sites should have adjustment angle settings based on one method of calculation.

The satellite is dual polarisation and if Eutelsat have put similar carriers on the opposite polarisation then it will be difficult to find a null using a spectrum analyser.  You need to be bold about the dish rotation.  If you turn the dish all the way through 360 deg you should see the two different polarisation spectrums, appear and disappear alternately, at 90 deg intervals, with very broad peaks and sharp nulls when each spectrum disappears.

The Tooway antenna design is such that beam should remain aimed at the satellite as the polarisation is rotated. If the feed support arm is sagging down (loose or not rigid enough) then this will not apply.

My opinion is that your adjustment angle should be -12.7 or -9.3 deg anticlockwise, as viewed from behind the dish and facing towards the satellite in the sky, starting with the arm at the bottom centre position.

Best regards, Eric.

Well done.

I'll take that as one vote that this calculation page Tooway satellite antenna pointing is giving correct results.

Regarding the LED displays I would have thought that anything above 5 dB would show signs of good receive operation and 10 dB certainly so (once the modem has spent time scanning, looking fo the caririer).

The table of LED lights on some older Surfbeam modems used in Ku band was like this:

I don't know if recent modems show the same results.

If your modem is stuck in the fast blink state I guess that it is Skylogic yet to transfer the site in their hub database to the new service provider. I think you may need a pin number at some stage.

Best regards, Eric.