[SOLVED] Is HDMI splitter bidirectional?

Nitromon

Honorable
Feb 14, 2015
34
3
10,545
Hi,

I've done audio splitting in the past and it works great, but I don't know if it will work with HDMI.

Now, I'm not looking for a "switcher," which usually comes with a button to switch between "2 or more inputs" into 1 output. Usually like 2 laptops to 1 monitor and it displays 1 at a time base on which input you split into.

I'm looking a whether a "splitter" can be used in the same manner, whether it is bidirectional? A typical splitter is unpowered, no buttons, and designed to split 1 hdmi output signal into 2 input signals for 2 displays. I want to use this splitter as 2-1 instead. The reason is simply that I will never use both at the same time, so it seems redundant to have a button to switch between the two.

Ok application:
I want to mirror my laptop to my TV, it currently only has 1 hdmi available. I want to get a dongle to do "wireless" mirroring, however I also want to leave a hdmi cable in place as a direct option or for other laptops that can't do wireless.

Now, yes I know a switcher will resolve this issue, but I'm wondering will a splitter do the same job since I will never use the wireless and wired input at the same time. Basically is the splitter bidirectional?

Thank you
 
Solution
So the connectivity requirement is:

TV [HDMI port] <------HDMI cable ----> [Output port] Switch [Inport port #1] Miracast dongle

and [Import port #2] <----- HDMI cable ----> [HDMI port] laptop(s)

"Laptops" being plural because you will be switching laptops from time to time via Import port #2.

Edit and correct my line diagram as necessary.

In any case here are a couple of links that address the matter in general:

https://www.digitalhome.ca/threads/...I switch would only,though it may be possible.

https://www.vention.cn/differences-between-hdmi-switcher-and-hdmi-splitter/

HDMI Matrix switch might be viable....

I used a very broad time frame for...

Ralston18

Titan
Moderator
Why not use Windows built in Duplicate screen function?

All you should need, if I follow correctly, is a HDMI cable from laptop to TV.

Press "WIN" + "P" and select Duplicate to see the same image on laptop screen and TV.

=======

That said - google "HDMI splitter".

You will likely get quite a number of links. Modify the search to narrow down to a product that meets your requirements.

Suggest that you sketch out a simple diagram to show devices, desired connectivity, cables, and plug/port genders.

Match any given product to your sketch.
 

Math Geek

Titan
Ambassador
what you are asking is if there is a monitor/kvm switch without the button to swap inputs. that's essentially what you want to do.

i've never seen such an item but then again i've never really looked for one specifically. my thought would be since this is a tv, there should be multiple hdmi inputs allowing on for your laptop and another for a loose hdmi for whatever else you need. seems easier than what you are looking to do.

some looking around turned up nothing but kvm switches to do the job. there were some "virtual" options that are basically remote desktop type options but if you don't want to press a button, i doubt you want to go through that effort.

i work with multiple pc's daily and have a kvm set-up so i can use 3 systems with one monitor/keyboard and mouse. it's really not any effort to flip the switch when i want to change inputs. i'm not sure how much time you think it takes but literally a second to reach over and move it to the input i want at the moment. considering you said you will only use one at a time (i use all 3 at once sometimes) and likely a single input most of the time, you're spending more time now trying to avoid the button, than the time it would save in total over a few years of use to just use a normal kvm switch!!
 

Nitromon

Honorable
Feb 14, 2015
34
3
10,545
Why not use Windows built in Duplicate screen function?

All you should need, if I follow correctly, is a HDMI cable from laptop to TV.

Press "WIN" + "P" and select Duplicate to see the same image on laptop screen and TV.

=======
Suggest that you sketch out a simple diagram to show devices, desired connectivity, cables, and plug/port genders.

I'm sorry, but that is not what I'm doing at all. I already have a HDMI cable attached to this TV and I use it often. However, I want to use a "wireless" one and I'm looking at a miracast dongle. However, I am not the only person who uses this TV for laptop. So I like to have both the wireless and the cable attached to the HDMI b/c miracast only works for newer hardware that matches a specific combination of Intel GPU, CPU, and wireless. Older laptops don't and would still need a cable connection.

A "switcher" would definitely do the job. It is usually a circuitry with a button that switches 2 inputs to 1 output. However, I'm just wondering do I really need something that complex? Would a splitter do the same if it is bidirectional? The cable I am using right now is bidirectional, which is why I'm wondering if a splitter is also bidirectional. Since the 2 inputs would never be on at the same time b/c most of the time if the wireless is being used, nothing would be attached to the cable.

Again, I use to do this with my audio system. I went to radioshack and they wanted me to buy some expensive switcher box and stuff, when all I needed was a splitter as audio cables are bidirectional. So I would have 2 audio devices (such as the CD player and a bluetooth receiver) both connected to the same input, however I would only use 1 at a time so I do not need a switcher box.

It all comes down to whether the splitter is bidirectional. From what I've been reading, HDMI is actually bidirectional. The only time it is directional is if the cable is designed to amplify and require power source from the HDMI. I'm wondering does a splitter require a power source? If it does, then it is likely directional and cannot be used the other way around. If it is a "straight through," then it is bidirectional.

-----


what you are asking is if there is a monitor/kvm switch without the button to swap inputs. that's essentially what you want to do.

i've never seen such an item but then again i've never really looked for one specifically. my thought would be since this is a tv, there should be multiple hdmi inputs allowing on for your laptop and another for a loose hdmi for whatever else you need. seems easier than what you are looking to do.

Hi,

Thanks for the reply. I didn't say it only has 1 HDMI, I said it only has 1 HDMI available. The other one is attached to a Roku. Currently the one that is used for laptop is just a cable and I'm thinking of getting a wireless dongle. However, as I am not the only person using this, I like to keep the cable connected for older laptops.

It's not as much the "trouble" of pushing a button as the location of where this would go. The HDMI is in the back, lower middle. A "switcher" requires a power source. This TV is too old and doesn't come with USB, so I have to use the power cord in the back. So in this case, a shorter HDMI cable to the TV is better b/c it is closer to the power strip. But that also means the button is stuck in the back of the TV and has to reach around.

Using a longer cable for the TV to the switcher allows me to put the switcher in the front or somewhere more visible and easily reachable. However, that means I'll have to get an extension cord for the power. So I'm merely wondering could this all be resolved simply with a splitter, if it is bidirectional.

Right now, I'm leaning towards a yes from most of my research, but I cannot confirm it. I was hoping someone who actually tried it can confirm it. If it is not possible, then I'll have no choice but to get a switcher. There are "auto" switchers out there, but I'm not sure how good they work.


=/
 
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Ralston18

Titan
Moderator
So the connectivity requirement is:

TV [HDMI port] <------HDMI cable ----> [Output port] Switch [Inport port #1] Miracast dongle

and [Import port #2] <----- HDMI cable ----> [HDMI port] laptop(s)

"Laptops" being plural because you will be switching laptops from time to time via Import port #2.

Edit and correct my line diagram as necessary.

In any case here are a couple of links that address the matter in general:

https://www.digitalhome.ca/threads/...I switch would only,though it may be possible.

https://www.vention.cn/differences-between-hdmi-switcher-and-hdmi-splitter/

HDMI Matrix switch might be viable....

I used a very broad time frame for search. Vary the search criteria and shorten the time frame to narrow down the results to identify "current" products that may meet your requirements.
 
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Solution

Nitromon

Honorable
Feb 14, 2015
34
3
10,545

Thank you so much! This one is so close to my question, but in reverse. It answers whether a switcher can be used as a splitter. From what I'm reading a switcher is more complicated than a splitter, it includes a circuit board, that is why most of them cannot be used in reverse without actual hardware modification.

Anyone know if a splitter is as complicated? Because a splitter doesn't require a button of any kind, I'm hoping it really is just splitting the wires into 2 identical output. In this case, it can be used in reverse so as long as they're not used simultaneously. However, if a splitter has some sort of circuitry, it might not work.

Some vendors listed that the splitter "copies" the signal from the source into 2. I am hoping that is NOT a technical description, just a selling description b/c copying implies a circuitry that takes the signal and duplicates it. I don't think a splitter needs to do that as a signal simply travels down wires and if you split that wire into 2, then you have 2 identical signals. Unless I'm missing something from the technology.

I think right now I'm opting for a "auto" switcher. There is still just so much I don't know about HDMI and my worry is that even IF a splitter is bidirectional and can be used in reverse, I know not to use both at the same time, but I cannot guarantee other users in the household would not do that. I don't want to know what happens if both input signals are connected at the same time combined into 1 stream. It may just get garbled signal in best scenario, but in worst case, if there are power distribution (which seems to be possible with HDMI) it might burn out the TV's HDMI or something. It's not worth the risk.

Thanks for all your help!
 
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