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Green screen

Passive HDMI switches simply connect one HDMI output to one of several inputs. Active switches (such as matrix switches) are powered units containing proper HDMI interfaces which break the handshaking between the source and the destination - the matrix switch is an active HDMI input as far as the source is concerned, and recreates an HDMI link to whatever is on the output (the TV or surround sound amp or projector).

The switch I bought can send the same input to two outputs, or separate inputs to the two outputs. I got it so I can feed my projector and/or the TV from the same selection of sources without fiddling with HDMI leads - my LG TV had no problems with Humax sync.

Some people route the HDMI through an AV receiver and then on to the TV - this is another means to break up the handshake chain. Imposing another device in the link (switch or amp) could resolve handshake issues as the TV might be happy with the switch's handshake.
 
Captain Clegg said:
Would this sort of thing do the trick?
Click to expand...
I suppose it might. "Supports up to 25m cable lengths each side" - neat trick if they can pull it off, AFAIK the HDMI spec bottoms out at 10m. The unit must be regenerating the HDMI signals to achieve that, but not necessarily re-handshaking (which is what you need). Handy that it is line powered.
 
I emailed the suppliers and they are not sure it will solve the problem, I know it is fairly cheap but switching off at the wall is cheaper.

MartinLiddle said:
Have you asked Humax?
Click to expand...

I have had lengthy email conversations, to no avail, they just seemed to stop replying. it is all very frustrating.

I guess I might even try removing the HDMI cable at night and replacing it when we want to watch something, a bit of a pain though, I'm also researching other boxes.
 
I have several items connected to one HDMI input on my TV via a Yamaha AV amp. I get handshake problems occasionally with one of them (an Acer Revo HTPC) and have found that I can get my picture back by switching the TV away from that particular HDMI input and then back again. Works every time. I've never had to power off the TV.
 
The other thing I have noticed recently is that when viewing through the hummy, the picture pixelates quite a lot, if watching through the TV then it is ok-is my hummy on the way out or this a common occurrence?
 
Captain Clegg said:
The other thing I have noticed recently is that when viewing through the hummy, the picture pixelates quite a lot, if watching through the TV then it is ok-is my hummy on the way out or this a common occurrence?
Click to expand...
What is the signal strength and quality as reported by the Humax when a) the picture quality is good and b) when it is pixellating?
 
Scouring the web I found this piece of information, I'm not sure how true it is though:

In the case of the Humax PVR, it's system chip doesn't even support 1080/50p, because the best it can ever output is 1080/50i, which is all we get broadcast and all we need. However the marketing for Full 1080p HD is so great, and buyers perceptions are the bigger number the better, Humax spent extra money adding a couple of chips that take the 1080/50i and de-interlace it to 1080/50p so they too could play the numbers game and say "it's full HD 1080p". Crazy, but that's marketing for you. It's also the addition of this extra HDMI de-interlacer chip which is probably responsible for the HDMI sync issues, and why they haven't added an auto switching option as switching between resolutions is a lot slower due to the extra chip in line of the HDMI signal.

From here:

http://forums.digitalspy.co.uk/showthread.php?t=1485720

If this is true, then there is no easy fix for this problem!:(:frantic:
 
Your HumaxPVR link points to this :- Humax HB-1000S Freesat+ which is a satellite receiver. It's true that the BCM7405 SOC used in the HDR-T2 only outputs 480i/480p/576i/576p/720p/1080i but as to whether the 'other' chips are causing the HDMI problems I'm not sure.
BTW
The broadcasters do now transmit 1080P and 1080i since that article was written, they even switch between them during the same programme
 
Captain Clegg said:
Would this sort of thing do the trick?

Neet© - 3 Port HDMI AUTO SWITCH 3x1 Mini Hub Box (3 way input 1 output) 1080p Full HD v1.3b HDMI Switcher

http://www.amazon.co.uk/Neet©-SWITCH-input-output-Switcher/dp/B001DAHS5Q/ref=sr_1_6?s=electronics&ie=UTF8&qid=1382356395&sr=1-6&keywords=hdmi matrix switch

Anything more expensive would probably not be worthwhile-I would just continue to power off at the socket.

No fixes from Humax yet?-surprising they haven't commented.
Click to expand...


I used to use a NEET 4 into one switch and encountered the same problems. Also, new ones. It was supposed to be auto-switching, but failed to switch if the Humax box was recording when it came on as the new input. I abandoned it long ago. It had an IR remote too, to manually switch, but that was also unreliable. The only reliable way was the push button on the switch, buried away behind the TV stand.
 
Captain Clegg said:
Scouring the web I found this piece of information, I'm not sure how true it is though:

In the case of the Humax PVR, it's system chip doesn't even support 1080/50p, because the best it can ever output is 1080/50i, which is all we get broadcast and all we need. However the marketing for Full 1080p HD is so great, and buyers perceptions are the bigger number the better, Humax spent extra money adding a couple of chips that take the 1080/50i and de-interlace it to 1080/50p so they too could play the numbers game and say "it's full HD 1080p". Crazy, but that's marketing for you. It's also the addition of this extra HDMI de-interlacer chip which is probably responsible for the HDMI sync issues, and why they haven't added an auto switching option as switching between resolutions is a lot slower due to the extra chip in line of the HDMI signal.

From here:

http://forums.digitalspy.co.uk/showthread.php?t=1485720

If this is true, then there is no easy fix for this problem!:(:frantic:
Click to expand...



So what happens when you use the Hummy as a media player? Does it convert 1080p down to 1080i then back up to 1080p?
 
Just a thought, has anyone tried connecting via RCA cables, or even RCA-HDMI, might get round the handshake problem, although I am not sure how good the quality would be, I know the scart connection is not that good.

I am going to give it a go and let you know.
 
The problem is that only the HDMI can supply High Definition, the SCART can supply RGB which is better quality than the Yellow (Video) composite RCA / Phono signal but is still only 576i as opposed to the HDMI 1080p/i. The SCART and composite outputs should still supply a video output during the HDMI 'green screen' as the problem is only HDMI handshaking
 
I didn't realise that there was a difference, now I know. I did know that scart quality is far worse than the HDMI connection, now I know why.

Looks as if I'll have to scrap the hummy then as it is not up to scratch, my old VCR lasted longer and is still working, must be an inbuilt self destruct mechanism.
 
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