Freeview PSB2 Macroblocking

[Pixelz]

All the channels on the PSB2 Mux (ITV4, Reality Xtra, London Live, etc) are displayed with macroblocking when received using my TBS 6284 quad tuner card.
This occurs over the top third of the display whenever there is a camera pan or zoom.
I am confident this is not a signal strength issue as other tuners are unaffected.
I wonder if PSB2 is using an encoder which is not fully supported by the TBS 6284, even with the latest drivers, but I've been unable to get support from TBSDTV.com

Anyone else in the UK had this problem?

[CyberSimian]

All the channels on the PSB2 Mux (ITV4, Reality Xtra, London Live, etc) are displayed with macroblocking when received using my TBS 6284 quad tuner card. This occurs over the top third of the display whenever there is a camera pan or zoom. I am confident this is not a signal strength issue as other tuners are unaffected.

I have a TBS 6284 quad tuner card which I use with MediaPortal on Windows 7. I am watching ITV4 (Tour de France) at this moment, but I see no defects other than the low resolution of standard definition broadcasts.

Possibly it is a transmitter problem? I am receiving from the Rowridge (Isle of Wight) transmitter, but I guess that you are receiving from Crystal Palace?

-- from CyberSimian in the UK

[Pixelz]

Thanks for the reply. Yes, I am on Crystal Palace but this has been a problem for over a year now and I'm not sure a transmitter problem would have persisted this long. Maybe I should look at my ATI Radeon graphics configuration as you're unaffected.

On an unrelated issue, I've noticed 7MC can't handle the MHEG data being transmitted on some channels now. In the worst case I've found Together TV and its +1 channel appear as a blank screen. Do you have this problem too?

[CyberSimian]

Yes, I am on Crystal Palace but this has been a problem for over a year now and I'm not sure a transmitter problem would have persisted this long.

Are you sure that this is not a signal strength problem? You said that "other tuners" are OK, but are these PC tuners, or TV sets? The tuners for PCs are generally less sensitive than those found in TV sets.

I have three different tuners available to me: a Sony TV, the TBS 6284, and a Pinnacle 2000i. The Rowridge transmitter broadcasts MUXes with three different power levels: 200 kW, 50 kW, and 20 kW.

- The Sony TV can receive all MUXes, albeit with occasional pixelation on the 20 kW MUX.
- The TBS can receive the 50 kW and 200 kW MUXes, but the 20 kW MUX is unwatchable (too much pixelation).
- The Pinnacle 2000i can receive only the 200 kW MUXes -- there is no sign of the 50 kW or 20 kW MUXes when a scan is performed.

I use a loft aerial, and I suspect that these reception problems could be eliminated if I had an external aerial installed.

If your other tuners are PC tuners that do not encounter this problem, it is possible that one or more of the TBS tuners has developed a fault. One change that I made to my TBS 6284 was to peel off the label on the tuner boxes on the card. The tuner box has ventilation holes in the lid, but these are completely blocked by the TBS label, which might risk overheating.

Do you have a spare PC tuner card that you can use to replace the TBS to check if the fault persists? USB tuners seem to be reasonably priced these days, but I don't know how reliable they are.

On an unrelated issue, I've noticed 7MC can't handle the MHEG data being transmitted on some channels now. In the worst case I've found Together TV and its +1 channel appear as a blank screen. Do you have this problem too?

I cannot help here as I do not "do" any internet TV or radio or music streaming. When "Together TV" reduced their Freeview hours to almost nothing, I deleted them from my EPG.

-- from CyberSimian in the UK

[Pixelz]

Thanks for the tip regarding ventilation on the TBS card - I'll give it a try.
I only have the one PCIe tuner since my BlackGold card failed, so I can't prove it's not signal strength. But my problem is not apparent on static scenes (when the camera's not moving). Nor does it happen with letterboxed wide-screen content (where the top part of the screen is unchanging).
If it's not a ventilation issue I might have to live with it, but thanks again for your time.

[IT Troll]

I’m running the TBS 6285 in the UK. I do find it is more sensitive to signal issues than my TV. I had to get 5G filter added after some channels moved to a MUX which was experiencing interference.