TBSDTV Community Forum

thanks for the useful information, there are some other 16APSK transponders over Europe except the one on Hotbird 13E satellite for example on 5W, 12.5W and 32APSK for example on 21.6E

Hello,

i had in last days email discussion with one italy guy who talked some time ago with mediaset engineer and he told him that mediaset freqs 13e/12.5w are in 8PSK. Constellation diagram of these freqs are differnet from normal 8PSK signals constellation diagrams, so we thought that it could be 16APSK: 1) fullring of clusters (16 clusters) but 16APSK has 12 + 4 in middle in diagram, so this was confusing and 2) mostly DVB-S2 receivers and pci card couldn't lock this mediaset freqs (some better like Prof card can, but with unstable notation) and 3) there is in using multistreaming on the mediaset freqs, what is typical for 16APSK (two transponders capacity in one) - screenshots are on EnoSat wepage. So since yesterday i saw 16APSK diagram on 31°E (EnoSat messaged you), where you really can see that missing 4 clusters in the middle and 12 in full ring we deduct that mediaset is running on one of the ACM or VCM DVB-S2 concept. Normal DVB-S2 freqs uses CCM (constant coding and modulation), but mediaset freqs must be running on ACM (adaptive coding and modulation) or VCM (variable coding and modulation), but not in 16APSK but 8PSK. VCM concept gives +28 % of increase in efficiency than mostly used concept CCM. That's what we dedcut.

Cody, what satellites (Ku/C band) you are receiving signals, we can try found for you some other UNKNONW/16APSK/32APSK signals/freqs with correct Symbol Rates, but without correct FEC.

PS: for example nice one 32APSK is on 37.5°W ku band, or i hope its still there, didn't check it few weeks

Regards,
DeEmEx

hello DeEmEx,

thank you for all the useful information and to EnoSat too. i believe we can use this forum thread to build some list of "strange" DVB-S2 transponders over Europe (and not only) and try to figure out what settings they are using. i agree that there is something more about Mediaset transponders. i should be able to receive most satellite that cover Europe, but i'm in our Shenzhen office now - i will be back in about one month.

regards,
cody

Hello,

good idea to collect here a list of unknown/apsk signals.
Receiving signals from 90°E - 45°W Ku band and 90°E - 37.5°W C band.

Regards,
DeEmEx

I have 1,1meter (at short axis) dish on h-h motor 103E-30W Ku and near Ku and C circular LNBs, but I have no 16APSK card yet (I hope yet).

Hi,

49°E - C Band:

found two 16APSK freqs:
- 3520 - L - 14400
- 4066 - L - 33400 (ex SatGate ISP provider freq)

Constellation diagrams (MODE/FEC telemann can't recognize right):

DeEmEx
Great work. You have found 4066 lost by me
May be Mediaset's signal is Turbo-coded 8PSK? Or Turbo-coded 8PSK is the same as ACM or VCM?

cody
What program support of TBS6925 plans: modules for AltDVB, DVBDream, drivers for WinXP, Win7x64?

Hi,

I haven't seen yet Turbo-coded 8PSK (dish netw. version) constellation diagram, so can't tell exactly what the hell it is what uses mediaset, i added how looks mediasat constellation diagram in my meter in picture below, so you can compare diferences between other modulations. Another deduction eliminating VCM concept, because VCM gives +28% increase of efficiency than normal 8PSK CCM concept, but in mediaset case you can see +100% increase of efficiency. There is yet ACM concept, but i don't have any informations about how many +% of efficiency increase is there related to CCM concept.

I searched more about ACM, and I think it can be excluded, it's seem impossible to implement in our case (Mediaset and Telecom "strange DVB-S2"). We are talking about the transportation of Digital Terrestrial multiplexes, ACM could works with one or few receivers, not thousands like in our case, and that is confirmed in this doc at page 7: "Distribution of multiple MPEG multiplexes to DTT transmitters [...] Adaptive coding and modulation is not considered, since multiple stations have to receive the same signals."

About those weird frequencies, I post here for everybody a link that I've already send to DeEmEx, it's the case study from Newtech about the DVB-S2 Multistream used by TIMB (Telecom Italia Media Broadcasting): http://www.newtec.eu/fileadmin/mailings ... -02-25.pdf

They are transmitting on Atlantic Bird 1 (12,5°W) frequency 12725H - SR 36.500, 4 Multiplex at 22,4 Mbps each. It's the same technique used by Mediaset, with the same problems to tune it by consumer receivers and PCI cards.

From EnoSat:
- 16APSK
- 31°E
- 11914 Mhz
- Horisontal
- SR 26400

strong signal: