Bulgarian channels 23.5E or 39E in Bahrain

[dzmei]

I got 5.3dB on 12524V, but couldn't get "locked" on the meter. I have noticed the BER was fluctuating from 0.3E-02 to 1.0E-05. Do you think the high BER was the reason?

Could someone tell me why I couldn't get "locked" on 12524V with 5.3dB on First Strike FS1 meter.

 

[Captain Jack]

5.3dB is a very marginal level for a lock. Lyngsat reckons you need a C/N of at least 5.5dB for DVB-S with FEC 3/4... but you should be able to get away with this a 5dB really. Have you tried locking this TP on any receivers?

 

[Huevos]

Lyngsat reckons you need a C/N of at least 5.5dB for DVB-S with FEC 3/4... but you should be able to get away with this a 5dB really.

No way. Lyngsat states the theoretical minimum. Even with 2/3 error correction you would struggle with a 5.5dB signal. But really all this depends on if it is a pro-grade meter that is properly calibrated. And I'd say if you are scoping for a 7/8 signal you really want a signal in the 9dB range as absolute minimum.

The 14dB signal on 11503 is going to be plenty for the CM 1.8 dish, but the others are going to need you to go up 4 or 5 dish sizes, so maybe something in the 3-4m range might just about be enough.

 

[BlindFaith]

12524 H went up to 3.7dB and in fact I care only about the H transponders where Bulsatcom is.

12525H is a DVB-S2 data transponder with 8PSK, 5/6 ;)

12525V is from SatelliteBG. It's DVB-S 27500, 3/4
minimum requirement for quasi error free reception are 5,5dB

 

[dzmei]

12525H is a DVB-S2 data transponder with 8PSK, 5/6 ;)
12525V is from SatelliteBG. It's DVB-S 27500, 3/4
minimum requirement for quasi error free reception are 5,5dB

Yep, we are talking about Hellas now at 39e. If the admins decide they can move it to a new thread.

 

[Analoguesat]

Ive altered the title so the posts can stay where they are

 

[BlindFaith]

That's better, I'd missed the switch to 39E ;)

@dzmei you can find the C/N requirements in the DVB-S(2) ETSI standards:

DVB-S -> EN 300 421

5 Error performance requirements
The modem, connected in the IF loop, shall meet the BER versus Eb/No performance requirements given in table 3.
Table 3: IF-Loop performance of the System
Inner code rate
Required Eb/No for
BER = 2 ´ 10-4 after Viterbi
QEF after Reed-Solomon
1/2 4,5
2/3 5,0
3/4 5,5
5/6 6,0
7/8 6,4
NOTE 1: The figures of Eb/No refer to the useful bit-rate before RS coding and include a modem implementation
margin of 0,8 dB and the noise bandwidth increase due to the outer code (10 log 188/204 = 0,36 d.
NOTE 2: Quasi-Error-Free (QEF) means less than one uncorrected error event per hour, corresponding to
BER = 10-10 to 10-11 at the input of the MPEG-2 demultiplexer.
Indicative figures of the System performance by satellite are given in annex D.

 

[Captain Jack]

Interesting. I can lock and watch with occasional break the Russian C band stuff on 11W at just 1.9db! The FEC there is 1/2.

 

[BlindFaith]

at just 1.9db!

..that only proves that the reading is wrong

 

[Captain Jack]

Probably - that's the reading on the Dr HD F15 receiver.

 

[<THOR>]

dzmei, why don't you try to receive the Vivacom package on Intelsat 12 @45E? Check the signal from 11632 V 30000 DVB-S2 8PSK 3/4.

 

[dzmei]

I tried some months ago, but didn't have the meter then... I thought the frequency duplication with the indian beam at 45e would make it "hard to get". No imagination at all from Intelsat :-)


P.S.
In the next few days I'll try to see what the meter reads.

 

[dzmei]

Some new results tonight from Hellas. The 1.6m offset completely outperformed the 2.4m prime focus. The signal is 3 to 4 db stronger on the 1.6m on all frequencies. I used Triax TTW 004 twin lnb. There are some trees in this direction and scattered clouds tonight.



P.S.

From Intelsat 12 at 45°e (Vivacom) I got 1.5db on 11468 V 30000 3/4 and 11550 V 30000 3/4 on all other transponders the signal is zero. I think bulsatcom looks more realistic. Just need bigger dish.

 

[dzmei]

Did some tests on Hellas sat 2 with Inverto Black Ultra Quad today. I got 7db on 12524 V - a bit better than the Triax twin, but all other frequencies are worse. 12524 H 5 db (6 db with the Triax), 12565 H 1.8 db ( 2.9 db with the Triax), 12565 V 2.4 db (same as the Triax), 12606 H DVB-S2 0 db (1.5 db with the Triax) 12647H 3.5 db ( 4.5 Triax ), 12688 H 4.8 db ( 5.8 Triax). All this on 1.6 m offset. Not very impressed with the black ultra quad. Both lnbs are brand new. I can post pictures later.

 

[<THOR>]

I have other idea. The Neterra's brand new bulgarian digital platform on 1W. Try 11881 and 11958/V/30000 DVB-S2 8PSK fec 3/4.
http://www.flysat.com/neterra.php

 

[Captain Jack]

Strange. I have never had an LNB better than the Black Ultra. They have quite a long neck and is very good for adjusting the focal point.

 

[Captain Jack]

Thor footprints don't seem to reach that far down..

 

[hexah]

Did some tests on Hellas sat 2 with Inverto Black Ultra Quad today. I got 7db on 12524 V - a bit better than the Triax twin, but all other frequencies are worse. 12524 H 5 db (6 db with the Triax), 12565 H 1.8 db ( 2.9 db with the Triax), 12565 V 2.4 db (same as the Triax), 12606 H DVB-S2 0 db (1.5 db with the Triax) 12647H 3.5 db ( 4.5 Triax ), 12688 H 4.8 db ( 5.8 Triax). All this on 1.6 m offset. Not very impressed with the black ultra quad. Both lnbs are brand new. I can post pictures later.

A proper seperate feedhorn like the Channel Master feedhorn a.k.a Andrews or Raven feedhoorn (the Invacom ADF-120 is not as good) and a C120 Invacom LNB should work best on the 1,65m dish. The right feedhorn makes a huge difference, it will get the weakest signals to the LNB.

The 2.4m dish looks like a Fortec Star dish and the common opinion is that it may as well be made of toilet paper. It is not suprising the 1.65m is better, holding an LNB in front of a wet towel would probably give a stronger signal than the Fortec Star.

 

[dzmei]

The 2.4m dish looks like a Fortec Star dish and the common opinion is that it may as well be made of toilet paper. It is not suprising the 1.65m is better, holding an LNB in front of a wet towel would probably give a stronger signal than the Fortec Star.

I can't agree more on that :-) ! I can strongly advise one not to waste money on this piece of j**k unless he only wants to use it's shade on a hot summer day.

The CM feedhorn is just a matter of time as a part of my upgrade project which includes a bigger dish too. As for the Black Ultra I can say for two days testing now on my antenna and 39°e, that it roughly adds 1db on the vertical transponders and takes down 1 db on the horizontal ones ( and I mainly care about them) compared to the mentioned Triax twin lnb. The black ultra is a top class lnb with no doubt, but IMO the Triax( both quad and twin) are the best LNBs I've ever had. I have no idea why they are not so popular. Maybe I was just lucky with them or a bit unlucky with this particular black ultra for the H tps.

 

[hexah]

Years ago when I had my big dish up I noticed on sunny days in the afternoon marginal channels would develop sparklies. Investigating the connections I found the metal LNB was warm to the touch so I painted the C120 LNB white to match the previously used LNB which was white. That cured the problem as the LNB was obviously cooking in the direct sunlight and the reflected sunlight from the 2m white dish.

The LNB is more than 20 years old and as you can see in my photo the paint has become a bit discoloured in storage.



Imagine how much more intense the sun is in Bahrain. A million times more intense that here I think. Anything black coloured will be cooking. So the white plastic of the Triax LNB will be giving it an unfair advantage.

Try covering up the white cap of the Black Ultra and tape up the f connection and spray it with 2 to 3 coats of white plastikote paint or similar.

(It will look far better than my crap attempts at painting, I didn't bother taking it off the dish. :-per)

See if that improves its performance.

Also the Black Ultra should hold on to the weak signal longer than the Triax, so the dB figure may be a bit misleading.