SES and ITV testing new FEC settings

timo_w2s

timo_w2s

Retired moderator
My Satellite Setup
Vu+ Duo 4K SE
Dr.HD F15
My Location
Maidenhead, UK & Helsinki, Finland
As you may know, SES and ITV are currently testing some new FEC settings on two DVB-S2 UK spot transponders (ITV 11053H 23.0 3/4 8PSK) and (SES 11464H 23.0 3/4 8PSK). In theory these need about 1dB extra signal to lock compared to similar transponders with a FEC of 2/3. Has anyone with smaller dishes looked at these tests in the fringes and noticed any problems?
 
In western part of Sweden, 11053 is like the other nearby transponders in signal strength but probably closer to the threshold. 11464 is stronger, approx 1-2 dB. I guess it can be due to I'm close to the first null and its higher frequency. So please ITV2 HD etc in FTA here...
 
timo_w2s said:
As you may know, SES and ITV are currently testing some new FEC settings on two DVB-S2 UK spot transponders (ITV 11053H 23.0 3/4 8PSK) and (SES 11464H 23.0 3/4 8PSK). In theory these need about 1dB extra signal to lock compared to similar transponders with a FEC of 2/3. Has anyone with smaller dishes looked at these tests in the fringes and noticed any problems?
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I, for one, was not aware of this, since my 2nd favourite alignment tool is my S1, (the first being my trusty old comwell receiver which is now in sat box heaven) does not have S2 capability, will try to check with the VU+, when wind allows, using the LH110 I set up a few days ago. Please don´t hold your breath as we have high winds forecast for most of the week. Even managed to break the F-type connector for my terrestrial aerial last night, so couldn´t check the weather for today!
 
You'll only have in issue if you're close to the drop off point of the "digital cliff" because you've got an undersized dish or bad weather. Where a current DVB-S2 transponder might get a lock with, say, 6.6dB these new tests should need about 7.9dB before they can lock because there is less error correction in the stream. The signal levels shouldn't change, just the point at which they become useful changes.
 
timo_w2s said:
You'll only have in issue if you're close to the drop off point of the "digital cliff" because you've got an undersized dish or bad weather. Where a current DVB-S2 transponder might get a lock with, say, 6.6dB these new tests should need about 7.9dB before they can lock because there is less error correction in the stream. The signal levels shouldn't change, just the point at which they become useful changes.
Click to expand...

OK TKS for the info. will advise asap, after wind, & tonights Seberano!

H, fixed the light yet?
 
North of Madrid (40.5458 ° N, 3.612 ° W) near Ikea, 94cm antenna.
Norte de Madrid (40.5458°N, 3.612°W) cerca de Ikea, Antena de 94cm.

DreamBox800S-HD 5-11-2014 13:00
11023 = 7.00dB SNR43% AGC99% BER 0 BBC 1 Scot HD
11053 = 8.50dB SNR53% AGC99% BER 40 ITV +1

DreamBox800S-HD 24-1-2015 20:05
11023 = 8.00dB SNR50% AGC99% BER 0 BBC 1 Scot HD
11053 = 9.00dB SNR53% AGC99% BER 0 20700/20701/20735/20780 (carta) Arqiva LMC HD

VU+DUO2 25-1-2015 01:00
11023 = 8.80dB SNR54% AGC69% BER 0 BBC 1 Scot HD
11053 = 9.30dB SNR57% AGC74% BER 0 20700/20701/20735/20780 (carta) Arqiva LMC HD

I can not look at levels far raining, very overcast and some snowflake.
No puedo mirar niveles ahora, lloviendo, muy muy nublado y algun copo de nieve.
DreamBox800S-HD
11023 = 6.50dB SNR40% AGC99% BER245 BBC 1 Scot HD
11053 = 0.00dB SNR00% AGC--% BER --- 20700/20701/20735/20780 (carta) Arqiva LMC
11464H= 0.00dB SNR00% AGC--% BER --- SES Promo
 
TBS 5922 USB DVB-S2 Tuner

20/12/2014 13:39:20
11022.662 Horizontal FEC 2/3 RFLevel -60 dBm SNR 10.4 dB
11052.807 Horizontal FEC 2/3 RFLevel -62 dBm SNR 11.1 dB
11427.246 Horizontal FEC 2/3 RFLevel -87 dBm SNR 4.7 dB

20/01/2015 16:51:34
11023.197 Horizontal FEC 2/3 RFLevel -61 dBm SNR 7.0 dB
11052.703 Horizontal FEC 2/3 RFLevel -68 dBm SNR 7.7 dB
11427.218 Horizontal FEC 2/3 RFLevel -90 dBm SNR 4.7 dB

03/02/2015 20:47:16
11022.857 Horizontal FEC 2/3 RFLevel -61 dBm SNR 9.5 dB
11052.645 Horizontal FEC 3/4 RFLevel -64 dBm SNR 9.5 dB
11427.928 Horizontal FEC 2/3 RFLevel -86 dBm SNR 8.4 dB
 
This is what I get on 11053 H but nothing on 11464H.
upload_2015-2-3_21-26-54.webp
 
Check your FEC for 11464H, it's 3/4, SR23000, DVB-S2 8PSK.
 
I did, but no lock, or luck.
 
Nagusia said:
I did, but no lock, or luck.
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Hmm, not good. Sounds like the null could be shifting closer to you at these higher frequencies or your LNB or tuner isn't as sensitive at that frequency.
 
Tururu said:
I can not look at levels far raining, very overcast and some snowflake.
No puedo mirar niveles ahora, lloviendo, muy muy nublado y algun copo de nieve.
DreamBox800S-HD
11023 = 6.50dB SNR40% AGC99% BER245 BBC 1 Scot HD
11053 = 0.00dB SNR00% AGC--% BER --- 20700/20701/20735/20780 (carta) Arqiva LMC
11464H= 0.00dB SNR00% AGC--% BER --- SES Promo
Click to expand...

Thanks for the report. It looks like you have problems with these new transponders in the bad weather.

Let's hope they don't use this for too many transponders.
 
Unable to check on LH110 yet due to wind, so had a quick look on the 1.8

11053 H 10.7db
11464 H 11.8db

compared to

11097 V 11.3db
10847 V 11.9db
11023 H 11.3db

Only significant thing is 11053 being 0.6db lower than worst other signal on 11097. Will try on LH110 later, wind or not!
 
If of interest to anyone, 11464 H has the strongest signal of all 2F UK up here.
 

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Brian Philpotts said:
Unable to check on LH110 yet due to wind, so had a quick look on the 1.8

11053 H 10.7db
11464 H 11.8db

compared to

11097 V 11.3db
10847 V 11.9db
11023 H 11.3db

Only significant thing is 11053 being 0.6db lower than worst other signal on 11097. Will try on LH110 later, wind or not!
Click to expand...

Yeah, the signal levels themselves shouldn't really be that different (other than the usual differences between transponders at the fringe) as they are still outputting at the same strength, but the way the data is encoded is what is critical, as it is harder for the receiver to decode correctly if the there is less error correction. 11.3dB sounds like you still have some leeway though on that setup. Will be interesting to see how the LH110 performs.
 
4wd said:
If of interest to anyone, 11464 H has the strongest signal of all 2F UK up here.
Click to expand...
I noticed a similar thing in Helsinki (although still way below lock for me!!), looks like the higher frequencies are more favourable for some of us. I assume this is down to the signal null shifting due to the change in frequency?
 
Remember, these are only tests and might not be implemented. Less signal margin = more outage during rain and calls to technical support / viewers switching to channels on stronger transponders. Seems unnecessary when there will be an abundance of over capacity at 28.2 once 2G arrives.
 
DeadHorse800 said:
Remember, these are only tests and might not be implemented. Less signal margin = more outage during rain and calls to technical support / viewers switching to channels on stronger transponders. Seems unnecessary when there will be an abundance of over capacity at 28.2 once 2G arrives.
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Very true, although I don't think capacity will be the main driving force here. I'm sure the likes of ITV and BBC would love to reduce their costs by squeezing in even more channels if they can get away with it. With BBC 1 English HD regions still to come there's quite a few new HD channels needed. Signal levels in the UK have also significantly increased with the new satellites (especially up north) so it's not too surprising they are trying out these new settings.
 
Have just tried on the LH110, but not really fair at the moment because the wind is causing intermittent loss on all 2E and 2F txps at the moment.

Only observation at the moment is that I can get intermittent lock on itv hd on 11097 V and bbc scotland hd on 11023, but nothing on 10847 or the new signals on 11053 or 11464
 
timo_w2s said:
Hmm, not good. Sounds like the null could be shifting closer to you at these higher frequencies or your LNB or tuner isn't as sensitive at that frequency
Click to expand...
I've done a blind scan on 11464 H with a TBS 5922 and there isn't even much of an RF signal. I tried with a Technomate TM 5402 HD and not a sausage either. The nearest TX I can see is 11428 H. Reception on all other channels is pretty good today. I'm going to change my IBU C120 DIY conversion for a Invacom quad one of these days but I can't imagine that will make much difference.
 
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