Hall projector only works with one laptop

[MarcLister]

We have a Casio XJ-UT310WN-UJ projector in the hall. I connect a 2012 MBP to the projector by way of a Thunderbolt-HDMI cable which plugs into an HDMI-Ethernet device because of the distance involved. The signal is then carried to the projector by Ethernet cable that then converts back to HDMI into the projector.

 

We've noticed that if my boss connects his 2017 MBP to the projector by using a USB-C adapter and an HDMI lead to the same HDMI-Ethernet device the MBP never detects the projector so we can't output from the newer MBP to the projector.

 

Last week we had an issue where a PowerPoint wasn't showing the images on my MBP so the teacher went and got his Windows laptop which has an HDMI socket. We plugged the laptop in using an HDMI lead and the laptop never connected to the projector.

 

Does anyone have any ideas what is going on so that only my 2012 MBP with Thunderbolt-HDMI works but 2017 MBP with USB-C adapter to HDMI or Windows laptop with HDMI don't?

[Joanne]

I'm absolutely no expert....

 

If the distance is too great, the signal won't carry. The MBP with the thunderbolt possibly sends out a slightly stronger signal?

 

What distance are we talking?

[MarcLister]

Hi Joanne,

 

The HDMI-Ethernet box was put in because HDMI wouldn't have lasted the distance whereas Ethernet does.

[Joanne]

Have you tried different HDMI-Ethernet adaptors?

[DalekSec]

I'm absolutely no expert....

 

If the distance is too great, the signal won't carry. The MBP with the thunderbolt possibly sends out a slightly stronger signal?

 

What distance are we talking?

The 2012 MBP will have Thunderbolt 2 the 2017 Will have Thunderbolt 3, shouldn't be a problem with the signal strength.

 

Have you tried any other Macs or maybe a windows PC? and have you tested the 2017 Mac with the adapter on a different projector to make sure the adapter hasn't gone pop?

[Katy]

Another thing to try, if you can get near enough to the projector (i.e. it's not hanging from the ceiling high up in the hall), do all these devices work straight into the back of it and only fail to work with the long HDMI/ethernet adapter?

[MarcLister]

Have you tried different HDMI-Ethernet adaptors?

Nope. One is easy to get to, the other we need a big ladder for.

 

The 2012 MBP will have Thunderbolt 2 the 2017 Will have Thunderbolt 3, shouldn't be a problem with the signal strength.

 

Have you tried any other Macs or maybe a windows PC? and have you tested the 2017 Mac with the adapter on a different projector to make sure the adapter hasn't gone pop?

Yep to Windows laptop. We tried a Windows laptop and the PC never registered the projector.

We also have a Saturday school who hire our hall on, erm, a Saturday morning. They've tried with a MacBook and a Windows laptop and the projector doesn't register with their devices either. I will see if I can borrow another colleague's MBP and see if that works. It is the same spec as my 2012 one. I have also just bought a second hand Lenovo laptop so when I get that I can use that for another test.

Another thing to try, if you can get near enough to the projector (i.e. it's not hanging from the ceiling high up in the hall), do all these devices work straight into the back of it and only fail to work with the long HDMI/ethernet adapter?

The projector is several metres up in the air on the hall wall above the stage. My thinking was I need to try and plug directly into that and bypass the HDMI-Ethernet extender but there are logistical challenges in doing this, namely getting a ladder tall enough and getting someone to support the ladder for me.

 

This is the model, or a very similar model, to our one. https://www.amazon.co.uk/Extender-Repeater-Function-Ethernet-Satellite-60M-RX-TX/dp/B00YC3BWL2/ref=sr_1_3?ie=UTF8&qid=1525951049&sr=8-3&keywords=hdmi+ethernet+extender&dpID=5148vRFXYZL&preST=_SY300_QL70_&dpSrc=srch

[synaesthesia]

Distance will continue to be an issue with those adapters, and HDMI>Ethernet adapters can be very picky for obvious reasons. The only ones I've seen working use 2 network cables and are rated up to 100m, one end of the adapter is powered.

[PotNoodleTech]

I'd wager it is a particular macbook thunderbolt > HDMI issue.

 

I bet if you grab 5 different laptops/netbooks/chromebooks from around the school they will all work fine.

 

Not big on thunderbolt macbooks so cant help any further.

[MarcLister]

Distance will continue to be an issue with those adapters, and HDMI>Ethernet adapters can be very picky for obvious reasons. The only ones I've seen working use 2 network cables and are rated up to 100m, one end of the adapter is powered.

The adapters are powered at both ends by mains.

I'd wager it is a particular macbook thunderbolt > HDMI issue.

 

I bet if you grab 5 different laptops/netbooks/chromebooks from around the school they will all work fine.

 

Not big on thunderbolt macbooks so cant help any further.

If it's a MacBook Thunderbolt/HDMI issue why does it also affect Windows laptops?

[PotNoodleTech]

Did you tell the windows laptop to actually output to the projector via HDMI? Usually you have to use the function key and the display key to cycle through either Laptop or HDMI or Laptop+HDMI?

[MarcLister]

Did you tell the windows laptop to actually output to the projector via HDMI? Usually you have to use the function key and the display key to cycle through either Laptop or HDMI or Laptop+HDMI?

I tried the Windows key + P to swap between computer only, duplicate, extend and projector only options. We selected duplicate and nothing happened. We plugged the HDMI lead in, took it out and re-plugged it in and the Windows Display wouldn't detect a second display.

[steveg]

We had very poor results with the hdmi over cat5 adaptors. In the end we got a fiber optic hdmi hybrid cable, and this has worked perfectly with whatever we have plugged into if over the last 3 years. It is 20m long.

 

Steve

[PotNoodleTech]

I am guessing there must be good adaptors and bad adaptors. I run long runs on HDMI>Cat5e in the hall etc and all works perfectly. I bought decent active adaptors (that need to be plugged into 240v).

 

If you are using passive then that may be your problem?

 

One thing to do could be to use a network tester to verify the cat5 run is actually fit for purpose?

[SamanthaD]

That projector is 16x10 native - so that maybe why the Windows kit isn't recognising it. (They output 16:9?)

 

The newer MBP maybe outputting HDCP - we have big problems with it. Your older MBP is probably on an older OS so not an issue?

 

My advice? Bin the HDMI and put VGA in! Or get rid of the adapters and get either active HDMI cables (up to 15m) or fibre optic HDMI cables - Kramer have released a couple of options that allow transmission up to 100m capable of 4k 4:4:4 @60Hz. Needless to say we've stopped using AV over Cat adapters now (we use Extron DTP systems) in favour of this...