[linux-dvb] Re : Re : No lock possible at some DVB-S2 channels with TT S2-3200/linux

Ales Jurik ajurik at quick.cz
Sat Jun 21 15:52:41 CEST 2008


Hi,

on the frequency you've mentioned I didn't have any problem (never). But at 
lyngsat it is reported as 11914MHz. I never used freq. shifting (only 
tested), it was not reasonable for me.

Problems I have are at transponders with 8PSK modulation. 

Thanks and Best Regards,

Ales


On Saturday 21 of June 2008, Dominik Kuhlen wrote:
> Hi
>
> ------snip----
>
> > > Could you please try the attached patch if this fixes the problem with
> > > nominal frequency/symbolrate settings?
> >
> > Many thanks, but I don't see any improvement. Minimum time after I've
> > lock is 150s.
>
> Could you please check whether the reported frequency is sane:
> Example: 19.2°E 11915MHz H 27500 DVB-S2
>
> Test1: use the nominal frequency:
>  ./simpledvbtune -f 11915 -d 2
> dvbfe setparams :  delsys=4 1315.000MHz / Rate : 27500kSPS
> Status: 1b: Signal Carrier Sync Lock
> SNR: 0 44 (0x2c) (4.4dB)
> BER: 0 0 0 0 (0x0)
> Signal: 5 170 (0x5aa) 1450 (145.0dBm)
> Frontend: if=1313.627 MHz
>
> Test2: set positive offset (+3MHz):
> ./simpledvbtune -f 11918 -d 2
> dvbfe setparams :  delsys=4 1318.000MHz / Rate : 27500kSPS
> Frontend: if=1313.660 MHz
> The frontend does automatically locks on the correct frequency
>
> Test3: set negative offset (-4MHz):
> ./simpledvbtune -f 11911 -d 2
> dvbfe setparams :  delsys=4 1311.000MHz / Rate : 27500kSPS
> Frontend: if=1313.650 MHz
>
> Find lower limit:
> ./simpledvbtune -f 11896 -d 2  (does not work)
> ./simpledvbtune -f 11897 -d 2 (works 100%)
> dvbfe setparams :  delsys=4 1297.000MHz / Rate : 27500kSPS
> Frontend: if=1313.654 MHz
>
> Find upper limit:
> ./simpledvbtune -f 11930 -d 2 (does not work)
> ./simpledvbtune -f 11929 -d 2 (works 100%)
> dvbfe setparams :  delsys=4 1329.000MHz / Rate : 27500kSPS
> Frontend: if=1313.645 MHz
>
> Which means:
>  - I can specify any frequency from 11896MHz to 11929MHz and get 100% lock
> success - and the Frontend (actually the derotator) reports the real
> frequency (e.g. for auto correcting the channels list)
>
> Cards I have tested so far:
> - pctv452e
> - mantis (Multimedia controller [0480]: Twinhan Technology Co. Ltd Mantis
> DTV PCI Bridge Controller [Ver 1.0] [1822:4e35] (rev 01) Subsystem: Twinhan
> Technology Co. Ltd Unknown device [1822:0031])
>
> Unfortunately I'm trapped behind a single-cable installation and have only
> access to 19.2°E Highband Horizontal
>
>
> Dominik





More information about the linux-dvb mailing list