27 Dec 2016

TBS 6903

Submitted by drhans

Some time ago I tested a couple of DVB-S PC tuners (read here) but TBS 6903 was not included. The winner of that test was a cheap TT-budget S2-4100, mainly thanks to blazing fast and accurate blindscan. Since then, I've added TBS 6903 to my collection.

This is a PCI-e based dual DVB-S2 tuner, packed with premium features, such as multistream support, 16/32 APSK modulation or high SR support. It's not the most recent model, therefore DVB-S2X is not supported.

After testing the tuner for some time, I'd say it works as expected, given the price tag, but it's not really a breakthrough. It's just a very handy tuner card, combining the best features out there. Still, the price of 230 Euro seems justified, especially since this is a dual tuner.

As usual, my tests focused only on those features that I really care for because those make the real difference when it comes to DX satellite reception, which requires fast and accurate satellite scanning. This means the speed and accuracy of RF Scan and Blind scan are the most important benchmark parameters.

A good RF scan can alone reveal transponder changes and new channels so it's important that the scan is not only fast but it also must show a meaningful graphical representation of what's going on, which is something that works well with TBS 6903 but the scans aren't as pretty and optically pleasing as those I could get with TT S2 4100 or TBS5925, but it's good. The RF scan speed is lacking behind most of the other tested tuners but it's not really as bad to make scanning uncomfortable.

Next important benchmark is the blind scan speed. With TBS 6903, the speed is as good as it can get, almost as fast as the TT S2 4100. The blind scan is faster when BLScan2 is used. However, using BLScan2 will render the online transponder analyzer not working in EBSPro, which means it's not possible to get the transponder content while performing blind scan. With BLScan, this works, but another issue comes up where CrazyScan won't find many channels. Despite BLScan2 having some limitations, it's pretty much worth it because it's fast and it's possible to see even the not locked transponders in the scan results, which is pretty cool.

The blind scan results are very satisfying: usually all transponders will be found and the SNR values reported in the scan result by EBS Pro or CrazyScan seem to be very accurate. On the other hand, the symbol rate reported for some transponders is not what other DVB tuners report so it's hard to tell when the SR reported by TBS 6903 is correct or not. TBS 6903 seems to be 1-6 KS off.

Here are the test results:

RF Scan: 24.9 s (20 pt)

BLScan2: 28.3 s (45 pt)

Locking with blindscan speed: 800 ms (35 pt)

Manual locking speed: 1100 ms (15 pt)

Blind scan accuracy: 5/5 (50 pt)

SNR accuracy: good (30 pt)

Total: 195 points = 85 %

And with 195 points, this makes the TBS6903 the highest scoring tuner so far!