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Текущая версия: Jim Screeechy ,

Текст:

There are a number of issues that can cause this problem, but essentially it happens when the HDMI handshake fails. The handshake happens so that a connection between the source and your TV can be established, and a channel for the communication of you signal can form… ie you can see the picture from your film player, service provider or picture source.
 
In my experience this is most often cable related. For example! You may have had a HDMI 1.4 (or lower) cable which worked perfectly with your older HD 1080 TV but you’ve now got a UHD TV which requires an HDMI 2.0 compatible cable (higher bandwidth for the most part) but you’ve not changed the cable. Now it may even be that the old cable actually worked perfectly for ten minutes, an hour, or even a day, then suddenly it stopped working, and you think waahh it was working fine its not the cable, but in fact it is.
 
Without going in depth into why this happens, suffice it to say it just does. Minute variances in tolerance will cause the connection to fail when it falls below a tolerable level. The handshake is unsuccessful either initially, or when it is re-checked after channel has already been established (ie your in the middle of your favourite soap or newscast). Yes, it does this re-check to ensure compatibility and suitability is maintained for better transmission standards, capabilities and robustness.
 
Always remember, if something has changed the likelihood is that this change is the cause or a contributing factor to the problem, so don’t just dismiss the new setup as ‘fine and dandy’ because it worked for the ten minute test you did when you unboxed the new TV. If you have changed TV particularly if you’ve changed to a higher resolution 2160 device after having had your standard HD for a while thethen UPGRADE THE CABLE. If you had a the old TV for a few years at least you probably did not have an HDMI 2.0 cable to start with and you may not even have had an HDMI 1.4, it may have only been a 1.1
Always remember, if something has changed the likelihood is that this change is the cause or a contributing factor to the problem, so don’t just dismiss the new setup as ‘fine and dandy’ because it worked for the ten minute test you did when you unboxed the new TV. If you have changed TV particularly if you’ve changed to a higher resolution 2160 device after having had your standard HD for a while thethen UPGRADE THE CABLE. If you had a the old TV for a few years at least you probably did not have an HDMI 2.0 cable to start with and you may not even have had an HDMI 1.4, it may have only been a 1.1
 
Generally it is best to start the TV first, then your Blu-ray player or other source device which will initiate the handshake. It Generally isn’t necessary to turn off a device for 15 minutes as suggested in some posts, as turning off merely restarts or repeats the handshake procedure. Going to the settings and removing the enhanced HDMI features may help as it removes some additional data for HDR etc (requires higher bandwidth) which your TV either may not support or may be causing the handshake process to fail. Some TVs can have different Name for this and indeed have different data sent ‘down the wire’ for additional services such as HDMI CEC which allows you to control other devices from a single remote. This can also cause problems in some circumstances, so all are best disabled at least initially till you establish the cause of the problem.
 
Also check your source. Some devices (older ones mostly) don’t initiate handshaking at all, (though it is mandatory in all US HDMI compatible equipment) and some have configurable options which may be preventing your handshake from succeeding. (my graphics card can disable HDCP a setting which my new 2160 TV refuses to accept though my prior HD TV didn’t seem to care about).
Also check your source. Some devices (older ones mostly) don’t initiate handshaking at all, (though it is mandatory in all US HDMI compatible equipment) and some have configurable options which may be preventing your handshake from succeeding. (my graphics card can disable HDCP a setting which my new 2160 TV refuses to accept though my prior HD TV didn’t seem to care about).
 
I know my post complicates matters somewhat, but all problems I have encountered with the “no signal’ error, regardless how stubborn, I’ve managed to solve. It does mean that there is no ‘one size fits all solution’ as some posts here imply, and sometimes if you’ve done the essentials (like the cable change) you may still need to be patient and try a few configuration combinations till you succeed. Also, avoid particularly long cables if you can help it, and if you have to go over 5 or 6 metres, make sure it is high quality cable.
 
Hope this helps
 
Screechy

Статус:

open

Оригинальный сообщение: Jim Screeechy ,

Текст:

There are a number of issues that can cause this problem, but essentially it happens when the HDMI handshake fails.  The handshake happens so that a connection between the source and your TV can be established, and a channel for the communication of you signal can form… ie you can see the picture from your film player,  service provider or picture source.

In my experience this is most often cable related.  For example! You may have had a HDMI 1.4 (or lower) cable which worked perfectly with your older HD 1080 TV but you’ve now got a UHD TV which requires an HDMI 2.0 compatible cable (higher bandwidth for the most part) but you’ve not changed the cable.  Now it may even be  that the old cable actually worked perfectly for ten minutes, an hour, or even a day, then suddenly it stopped working, and you think waahh it was working fine its not the cable, but in fact it is.

Without going in depth into why this happens, suffice it to say it just does.  Minute variances in tolerance will cause the connection to fail when it falls below a tolerable level.   The handshake is unsuccessful either initially, or when it is re-checked after channel has already been established (ie your in the middle of your favourite soap or newscast).   Yes, it does this re-check to ensure compatibility and suitability is maintained for better transmission standards, capabilities and robustness.

Always remember, if something has changed the likelihood is that this change is the cause or a contributing factor to the problem, so don’t just dismiss the new setup as ‘fine and dandy’ because it worked for the ten minute test you did when you unboxed the new TV.    If you have changed TV particularly if you’ve changed to a higher resolution 2160 device after having had your standard HD for  a while the UPGRADE THE CABLE.   If you had a the old TV for a few years at least you probably did not have an HDMI 2.0 cable to start with and you may not even have had an HDMI 1.4, it may have only been a 1.1

Generally it is best to start the TV first, then your Blu-ray player or other source device which will initiate the handshake.   It Generally isn’t necessary to turn off a device for 15 minutes as suggested in some posts, as turning off merely restarts or repeats the handshake procedure.   Going to the settings and removing the enhanced HDMI features may help as it removes some additional data for HDR etc (requires higher bandwidth) which your TV either may not support or may be causing the handshake process to fail.  Some TVs can have different Name for this and indeed have different data sent ‘down the wire’ for additional services such as  HDMI CEC which allows you to control other devices from a single remote.   This can also cause problems in some circumstances, so all are best disabled at least initially till you establish the cause of the problem.

Also check your source.  Some devices don’t initiate handshaking at all, (though it is mandatory in all US HDMI compatible equipment) and some have configurable options which may be preventing your handshake from succeeding.  (my graphics card can disable HDCP  a setting which my TV refuses to accept though my prior TV didn’t seem to care about).

I know my post complicates matters somewhat, but all problems I have encountered with the “no signal’ error, regardless how stubborn, I’ve managed to solve.   It does mean that there is no ‘one size fits all solution’ as some posts here imply, and sometimes if you’ve done the essentials (like the cable change) you may still need to be patient and try a few configuration combinations till you succeed.  Also, avoid particularly long cables if you can help it, and if you have to go over 5 or  6  metres, make sure it is  high quality cable.

Hope this helps

Screechy

Статус:

open