Re: EUTMETCast DVB-S2 Unable to lock


Quentin P.A. Leroy
 

Thank you very much everyone!
Your help has been very useful and instructive.

I played around with the azimuth, with the tuner set at 1512.500MHz, to see what signal I could get.
The receiver locked on 4 different satellites. I could easily observe distinctive peaks of signal power around each location.
I swept about 60 degrees around South. Three were on the edges of that angle window, one was close to the theoretical direction estimated via www.dishpointer.com + landscape reference.
This method is a good start, but I found it difficult to visualize a central axe on the dish to aim at those references in one view.
So I assumed it was reasonable to end up with a couple a degrees off (5-10) to the actual observed power peak with signal lock.

The fact this "locking" position is a bit to the right of the supposed Hotbird 13°E position corroborate my idea that I found the correct satellite.

With this on field observation, I am now thinking that I would probably not see a significant power drop between Eutelsat  9A and Eutelsat  10A considering they are 1° apart from each other and there was clearly no such signal peak at this frequency in a 15° angle window around.

Here is my new signal lock:
RX1: Active, Locked
 EUMETCast DVB-S2 T1 1512.500 MHz, DVB-S2 8PSK 3/4, 29.996 Msps, CCM, 11.8 dB

RX Status 1, Configuration 2
============================
1. Tuner Status                                  Locked
2. Demodulator Status                        Locked
3. Transport Status                             Not Locked
4. Demodulator Frequency Offset      2348 KHz
5. Demodulator Es/N0                        11.7 dB
6. Signal Input Level                           -28.0 dBm
7. Demodulator BER                           0.00 e-7
8. Bad Frame Count                           0
9. Bad Packet Count                          0
A. Demodulator Link Margin               3.5 dB
B. Modulation Order and Code Rate      DVB-S2 8PSK 3/4
C. Link Adaptation                            CCM
D. Pilots                                            On
E. Frame Type                                  Normal
F. Roll Off                                          35%
G. FPGA                                           Loaded

Although I realized afterward the 22KHz was ON during my azimuth scan, with a tuner frequency set at 1512.500MHz, I saw the demodulator frequency offset dropping when I desabled the 22KHz, SNR increased, and the signal status remained on "locked". So I guess this is not a problem.

Transmission Standard is correct (DVB-S2), modulation is correct (8PSK), code rate not exactly (3/4 instead of 3/5), but it was varying a lot in the beginning.
I believe I am now very closely pointing at Eutelsat 9 or 10.

Unfortunately, as you can see the Transport Status is still Not Locked, while I do receive some packets.

RX1 Transport Statistics
=======================
No.           MPEG           MPE       MAC Mismatch    MPE CRC Errors

  1.        110522          49138             45634              3504
  2.        3384              3382               3362                20
  3.        23900533      23900533       0                      23900538
  4.        5134              5129               5099                30
  5.        13                  0                     0                      0
  6.        17                  43                   0                      5
  7.        1752              1743               1740                3
  8.        1493180        8950                0                     8948

RX Transport Filter Table
=========================

Slot.    PID     Ethernet Address           Status      IP Multicast
   1.    100    CC-F6-7A-04-CA-B8          Enabled            Pass
   2.    300    CC-F6-7A-04-CA-B8          Enabled            Pass
   3.    301    CC-F6-7A-04-CA-B8          Enabled            Pass
   4.    500    CC-F6-7A-04-CA-B8          Enabled            Pass
   5.    509    CC-F6-7A-04-CA-B8          Enabled            Pass
   6.    511    CC-F6-7A-04-CA-B8          Enabled            Pass
   7.    600    CC-F6-7A-04-CA-B8          Enabled            Pass
   8.    601    CC-F6-7A-04-CA-B8          Enabled            Pass

What does the Transport Status actually means?

Greetings,
Quentin

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