Hardware Problem?

[Derrick]

I've noticed some serious problems with my TBS6925 when analyzing very high bitrate transponders (e.g. 23,E 12645H, 12685H, 12725H all DVB-S2, 30000, 8psk, 8/9)

Though SNR seems to be good the BER sporadically jumps to bad values. This results in ts_packet discontinuities and wrong ts_packets. Another card (Prof 7500) doesn't count any errors at al. The BER always stays at 0.

Can somebody check these transponders? I suspect a possible hardware fault.

[sotos65]

Are those on Astra 3A or 3B?

[Derrick]

http://www.lyngsat.com/astra23.html

it's almost certain hardware related cos it's worse in the beginning after the PC was started

[sotos65]

Ok, European (so called) beam, quite low (and not lockable) signal here. If those were on the pan-european beam they would give very strong signal...

Btw, the problem can be software related as well, how can you tell?

[crazycat]

Monitoring SNR,BER while IQScan in progress or streaming active in CrazyScan not reliable, because used I2C-acess from user-space application via specific driver calls for I2C-access. Latest beta drivers 1.0.1.7 improve I2C-access from user-space (maybe reduced delays), so test it.

If possible, need continous monitor transport stream integrity and level/quality from driver. Some users also report me about sporadical picture artefacts on 6925 V2 with BDA2-module for AltDVB (which work via BDA-driver).

[steven]

Hi

Thanks for crazycat's explanation,yes 1.0.1.7 have improve I2C-access speed.This should be better than before

Thanks

[Derrick]

Monitoring SNR,BER while IQScan in progress or streaming active in CrazyScan not reliable, because used I2C-acess from user-space application via specific driver calls for I2C-access. Latest beta drivers 1.0.1.7 improve I2C-access from user-space (maybe reduced delays), so test it.

If possible, need continous monitor transport stream integrity and level/quality from driver. Some users also report me about sporadical picture artefacts on 6925 V2 with BDA2-module for AltDVB (which work via BDA-driver).

1.0.1.7 was used. I don't take crazyscan as a professional measurement tool but there is a clear correlation between BER_peaks and continuity counters in tsreader.

Here's another test without crazyscan. Simultaneous analyzing the same transponder received with TBS6925 on the the left and with TBS9821 on the right. To exclude cable problems the tests were repeated with swapped cables. Same result

[satesco]

1.0.1.7 was used.

If this can help you to make a correct diagnosis with the last driver beta TBS6925 card, here's a picture of the frequency 12658 H, 30000,8/9 with TS Analyzer,the same tool you used.My OS is Windows 7 64 bit :

[steven]

Hi Derrick

Is this problem occured before?
and would you mind try to test 1.0.1.8 driver.
here is the linker:
http://hotfile.com/dl/128569329/54f430f ... 8.rar.html

Thanks

[Derrick]

Is this problem occured before?
and would you mind try to test 1.0.1.8 driver.

..thx @steven but no improvement with the new driver. The problem is new, at least I've never noticed this before.

I seems that the performance is getting worse. Even DVB-S2 transponders with much lower muxrates now show massive errors. Crazyscan doesn't lock the high rate transponders any more and ony shows the constellation diagram. Thus the IQ tuner output is still ok but the DVB-S2 demod seems to be broken.

Also thx to @satesco for the test. I guess I have to get a ticket for replacement..