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HDMI Problem

anoraknophobe

Standard Member
Hi. I have an Amstrad SKY+ HD box connected to a Toshiba WLT66, using a 15m HDMI cable. Trouble is, we get the picture/audio 'jumping' frequently which gets very annoying. I tried another cable (from same retailer/producer who was very helpful) thinking that the original is faulty and the same happens. I know the connection from the Sky box is OK 'cos I sometimes connect it to my PJ and it works fine.

I then tried switching the cable into the other HDMI input on the TV. However, but it gives me other problems, i.e. sometimes I get no picture or audio, and other times I get a picture (which doesn't seem to be jumping) but no audio! If I change inputs on the TV and then back to the HDMI1 then the picture can disappear again!

Anyone know what the issue is here? The cables were supplied by a reputable company (who have a presence on this site!) and I assume it would be unlikely to get 2 faulty cables. Are these the dreaded 'handshaking' problems that I'm getting? Or is it perhaps a TV issue (but why different results on the each HDMI input - both bad in different ways)?? Help :lease: as the jumping is starting to drive us all nuts.
 

Joe Fernand

Distinguished Member
AVForums Sponsor
Hello anoraknophobe

Whilst a 15m run is fairly commonplace these days it can still be problematic.

There are plenty of 15m cables that work most of the time but few that tend to work all of the time - The Media Factory

We get plenty of folk with similar problems to your own ordering our HDMI Extender product to use with all manner of well recommended cables - Media Factory - Octava HDE-UK, HDMI cable extender

The voltages being output by your Source are very low level and its very easy for those signal levels to drop just enough to cause the Sync (your TV) to loose the signal - keep in mind too your 'only' dealing with 1080i!!!

Its not unusual for TV's to have different Receiver chip sets behind multiple HDMI sockets - often one Input is CEC compliant whilst others are not.

Joe
 

anoraknophobe

Standard Member
Joe,

thats great, and I understand what you're saying. However, I didn't really want to spend £80+ extra to fix this. I appreciate that 15m cables can be problematic, but in that case, surely they shouldn't be sold, or should be sold with money back guarantee? If I buy something, surely it has to be fit for purpose, and not just possibly fit for purpose and with the need to spend more on other accessories to make it work.

If this length of cable is merely problematic, should I just ask the supplier for another, and keep going until I get one that works?
 

Joe Fernand

Distinguished Member
AVForums Sponsor
Hello anoraknophobe

Any cable we (TMF) supply has a money back guarantee - we always explain to prospective customers that whilst our 15m cables work 99% of the time we cant guarantee 100% as that's not the nature of the HDMI beast.

No cable supplier can guarantee any HDMI cable over 5m will always work - the HDMI standard does not define the recommended or max distance between Source and Sync (your Display).

The cable you install is a conduit - the best it can do is not significantly degrade the input signal; though that doesn't recognise that the output signal voltage of the source device may not drive a long cable.

HDMI.org are as clear as mud on the subject - HDMI :: Consumers :: How to Connect

You can try 100 cables and still not getting a working system at 15m and may have to go with an active system - either an active extender or go with HDMI over CAT5; Media Factory - Octava HDMICAT-UK, HDMI over CAT5 extender

Joe
 

anoraknophobe

Standard Member
Joe,

our 15m cables work 99% of the time

You can try 100 cables and still not getting a working system at 15m

I am not trying to be awkward, but these two statements are contrary to each other. If the success ratio of your (and other suppliers) 15m cables is as you describe, then surely if I got one non-functioning cable, all I'd have to do to get one to work is try one or maybe two others before I'd get lucky.

Saying that, I do appreciate the need for the extender and CAT options in some circumstances.
 

MarkTaylor

Well-known Member
Joe,I am not trying to be awkward, but these two statements are contrary to each other. If the success ratio of your (and other suppliers) 15m cables is as you describe, then surely if I got one non-functioning cable, all I'd have to do to get one to work is try one or maybe two others before I'd get lucky.

All it takes is a low output from your source or a very picky display device and as Joe says, you could end up trying a lot of cables without success.

The cable is not the only variable so when you look at other people running happily at 15m, unless you have identical equipmet, their example is not a lot of help for you.

The cable is not necessarily at fault, the best it can do is transfer the signal it is given with mimimal loss, if the signal it is given is poor then it can be a perfect cable and still not work for you with your specific equipment.
 

anoraknophobe

Standard Member
OK - back again after a few days away!

This may be simplistic, but I feel the point is worth putting.

All it takes is a low output from your source
OK, but the source is Sky+ HD (Amstrad). Presumably these output a constant signal strength from each box of this type. If this is such an issue, why are there no warnings when you buy a cable of this length, e.g. **May not work with Amstrad Sky+HD boxes** !

Or, similarly, if the display kit is the issue, why no warning saying that cables may not work with some display equipment??

Instead, cable retailers are keen to say things like ... "99% guaranteed" or "you shouldn't have any issues", which doesn't make sense if 15m cables are so problematic.

Are retailers not being transparent:nono: ;) ...... or.... is my problem not that common, and either I'm having very bad luck or there is some other issue.

So far, the response to the post seems to be that this length of cable can be a hit or a miss, in which case I don't feel retailers are giving all the info. If this is not the case, are there any other solutions to my problem? Try another cable??

Just looking for clarity and logic, thats all. :confused:
 

Joe Fernand

Distinguished Member
AVForums Sponsor
Hello anoraknophobe

HDMI was never intended to run over long (10m+) cables - see what the folk who own/design the standard say about 'long' cables.

'Q. Does HDMI accommodate long cable lengths?
Yes. HDMI technology has been designed to use standard copper cable construction at long lengths. In order to allow cable manufacturers to improve their products through the use of new technologies, HDMI specifies the required performance of a cable but does not specify a maximum cable length. We have seen cables pass "Standard Cable" HDMI compliance testing at lengths of up to a maximum of 10 meters without the use of a repeater. It is not only the cable that factors into how long a cable can successfully carry an HDMI signal, the receiver chip inside the TV or projector also plays a major factor. Receiver chips that include a feature called "cable equalization" are able to compensate for weaker signals thereby extending the potential length of any cable that is used with that device.

With any long run of an HDMI cable, quality manufactured cables can play a significant role in successfully running HDMI over such longer distances.
'

HDMI requires a +5v power supply between the Source and the Sync (display) - the power on that rail must not drop by more than 0.3v or you can have problems - lots of 15m cable assemblies will cause the signal to drop by more than 0.3v.

Anyone I speak to is told to pre test any long cables they intend to use/install before they bolt them into place.

You can try more samples of the cable assembly you already have, a different cable assembly (The Media Factory) an active extender (Media Factory - Octava HDE-UK, HDMI cable extender), switch to HDMI over CAT5 (Media Factory - Octava HDMICAT-UK, HDMI over CAT5 extender) or move things closer together.

In between times you can join the rest of us and have a swift kick at, swear at or take a hammer too any handy HDMI equipped devices.

Joe
 

anoraknophobe

Standard Member
Joe,
HDMI requires a +5v power supply between the Source and the Sync (display) - the power on that rail must not drop by more than 0.3v or you can have problems - lots of 15m cable assemblies will cause the signal to drop by more than 0.3v.
...so if someone is selling a 15m cable, surely it will have been tested for this first, knowing that it can cause problems ? I assume anyone stating that their cable meets the HDMI standard will have done so?

Anyone I speak to is told to pre test any long cables they intend to use/install before they bolt them into place.
Not explicit though is it when you are asked to hit the "Buy now" button!

If a cable does meet the standard, and doesn't cause a 0.3v drop between source & sync, and the source voltage is >=5v, what else could be my problem??
 

Joe Fernand

Distinguished Member
AVForums Sponsor
Hello anoraknophobe

I don't have a 'buy now' button on my site for exactly that reason - means folk tend to talk through their requirements with us before we ship goods!

Testing a sample of a cable assembly on a test bench is one thing - burying them in walls is another!

Where to start on the many problems inherent in HDCP and EDID over HDMI cables!!!

Assuming you get 5v over the cable (and it stays that way over time - often you can start with a working signal and then find it starts to drop out after a few hours) and the Sync device can lock to the signal you may have HDCP and or EDID compatibility issues.

The only way to guarantee you wont have an issue with HDMI is to avoid it at all costs - otherwise stick with suppliers who are hands on with the stuff!

Joe
 

griffo2112

Standard Member
I have a similar problem and coming across this thread has been very helpful. I have a Sky HD box that I want I have connected to a Panasonic PT-AE3000 projector via an Onkyo TX-SR307 amp. The cable is 5 metres, (HAMA if I remember well) but the signal drops off all of the time i.e. I have not had any kind of decent stable picture lots of snow or no picture or flickering all of the time. I assumed that the cable was not good enough but I connected it directly to the TV, Samsung SP-50L7HX which works perfectly fine. Does anyone have a view that the acceptable signal on the TV comes from it being less picky about the strength and the former set up is more in need of a better signal, indicating I need a better cable or some kind of signal booster.

Thanks in advance for any opinions.
 

Member 319784

Well-known Member
5m really shouldn't be a prickly distance for a good quality cable to be honest.

I would be happy to send you one of our cables to try before you buy.

You can contact me direct at [email protected] with your address details and I will sort it out for you.

Kind Regards

J
 

Member 213491

Active Member
Hello griffo2112,
Can you please check how thick the product us. We use 26 AWG cables for 5m plus. The lower the guage the thicker the cable. The thicker the cable the better the performance, less signal drop outs.

We have 50m cables that do 1080p without an issue.

You can try our
Ikuna 5 Metres HDMI Cable
or
Ivuna HDMI Cable 5 Metres

If youre not happy with the product full money refunded including the postage.

:clap:
 

griffo2112

Standard Member
Thanks for the responses so far. I am not sure how thick it is but it seems to be about the same thickness as a bog standard scart cable. The cable I have seems to be HAMA E119932 AWM style 20276 80oC 30v VW-1 HDMI 1.3 copartner. What bothers me is that is seems to work fine with the TV but not with the receiver/projector set up. I live in Hungary where HAMA type cables seem to be the norm in most electrical retailers but will be in the UK in two weeks time for a holiday. The purpose of this investigation is to see if there is anything obviously wrong and try and pick up a cable that will do the job. Having reorganised my various boxes with todays purchase of the receiver 5 metres is probably 3 metres too short to be able to put the cables out of sight. As a result I am probably looking for something in the 8+ metre range so any further comments would be highly appreciated.

Thanks again.
 

Member 319784

Well-known Member
8m + is a cable length where you really really need to ensure the cable is quality and most importantly meets specification.

8m is the maximum distance you can go to with the HDMI 1.3 Cat2 High-Speed rating.

When buying a long cable, ensure you check the credentials of the cable. Have a look at the ATC certificate confirming that cable model meets the specification and check that the manufacturer is listed on the official HDMI adopter list at HDMI.org, the manufacturer should be able to provide you with a copy of the cert.

If all these boxes are ticked you are guaranteeing yourself that you are purchasing a genuinely high quality top-spec cable.

Kind Regards
J
 

anoraknophobe

Standard Member
Hello griffo2112.

after posting here and considering the feedback, I went back to my retailer who kindly offered either a replacement cable or an HDMI extender to 'boost' the signal. As I had already tested 2 cables, I didn't think another would necessarily make a difference so tried the extender instead, which was also a suggestion made by some members here. The extender seems to have solved the problem and so if I was you, I'd try that, but ask the retailer to fund it as the cable has not worked (even though it's not faulty!!)
 

Joe Fernand

Distinguished Member
AVForums Sponsor
Hello griffo2112

Your 'testing' your cable in two very different set-ups.

The cable is unlikely to be the root of the problem - its more likely the combination of the Projector and Onkyo AV Receiver having handshaking issues.

Can you try connecting your Source direct to the Projector bypassing the AV Amp.

Is the TV a separate system or are you using some form of signal splitter in a combined TV + Projector set-up?

Joe
 

griffo2112

Standard Member
Thanks for the responses so far. I effectively have two HD set ups. The projector and the amp are connected to each other with the Blu-Ray player for watching Blu-Ray discs and DVD's on the big screen. The TV is for normal day to day use and is attached to the Sky HD box which is connected with a short HDMI cable which works perfectly fine. I want to be able to see some of the Sky content in HD on the projector so bought the long cable for this purpose. I effectively unplug the short one to the TV and plug in the long one connected to the amp. This is probably not a good long term solution so subject to solving the cable problem, some kind of splitter would be a good idea (any suggestions of a reasonably priced but effective splitter that also boosts the signal (if the two concepts work together) would be appreciated).

I also tried the connection directly to the projector which was even worse i.e no picture at all !!! Its just a bit wierd that the connection to the TV shows no such problem.

I believe based on the feedback that the cable needs to be replaced as there was a time, when I first bought the projector - during the winter, when the cable worked Ok when directly connected to the projector and then stopped. I was hoping that the purchase of a proper home cinema amp which had the HDMI connections would improve things, which it it has not really done.

I plan to pick up an 8-10 metre proper cable when I am home and I will report back in the end how things went.

In the meantime your comments have been an invaluable source of info so thanks again.
 

Joe Fernand

Distinguished Member
AVForums Sponsor
Hello griffo2112

We find Projectors to be far more sensitive to signal drop and HDCP/EDID issues compared with most Plasma and LCD Display's.

Plugging and unplugging is tricky (as well as not too great in terms of cable connectors and input output port long term reliability) with SKY HD as often if you have left the SKY box powered up it doesn't properly announce itself to the Sync device (AV Amp, Switch or Display) when you make the new connection - powering the system fully off is always the best option rather than hot plugging.

Have a look at the Octava HDDA12-UK when considering a 1x2 Splitter - Media Factory - Octava HDDA12-UK, 1x2 HDMI distribution amp.

Joe
 

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