Convert Your VGA Projector into a Wireless Display Using Miracast
03/25/2014
Miracast is a wireless display technology that allows teachers/presenters the ability to “mirror” what is on their Windows 8.1 tablet or Android tablet screen up to the big screen.
It has long been a dream of teachers to have the ability to roam about without being tethered by a device that is connected by wires to a projector at the front of the room. That tether-less dream is now a reality thanks to miracast and other wireless display technologies.
It has long been a dream of teachers to have the ability to roam about without being tethered by a device that is connected by wires to a projector at the front of the room. That tether-less dream is now a reality thanks to miracast and other wireless display technologies.
I have been testing out a classroom wireless display solution over the past couple of weeks for VGA projectors that many others may benefit from.
It is often necessary for schools to maintain older generations of technology due to budget constraints and this often leads to compatibility problems over the years as the new tries to replace the old. VGA projectors are a good example of this and are prolific in our schools today. VGA has long been a display standard for over two decades and there are millions of VGA compatible devices that are still in service today.
Note: You can click on an image to enlarge, press the Back button in your browser to return to this page.
In recent years HDMI has gradually replaced VGA as the standard for large screen displays. This is definitely true for HDTVs and if you are buying a new classroom projector today it makes sense to make sure it can support both VGA and HDMI connections. Unfortunately, many schools do not have the budget to replace older projectors so the ideal solution would be to find a wireless display technology that can still work with the older VGA standard AND also support the newer HDMI standard going forward.
I think I have found a solution that does both.
Here is our current problem, only about twenty percent of the classrooms within our college have a projector with built-in HDMI. The good news is that ALL of our classrooms have a connection that will work with a laptop that has VGA output connected to a classroom projector.
Many newer laptops have stopped providing a VGA port and only offer HDMI or a Display Port. We are in one of those transition times where a two decade old standard is being phased out but because of the sheer momentum of its success VGA still needs to be supported. What to do?
I have been using Miracast to wirelessly display Windows 8 tablets for well over a year now. Miracast has become better and more stable over this time and is proving to be an affordable and reliable solution for wirelessly displaying (mirroring) what is on my tablet screen up to the big screen.
Below is a link to a video I did over a year ago that demonstrates miracast in action:
This is huge for teachers and students as new wireless sharing possibilities can change the dynamics of the classroom environment. Combine this new wireless display technology with Cloud services and we truly have some game changing technologies available to us as teachers.
Usually a new standard means getting out the checkbook and spending large amounts of money to re-tool to the next standard. Schools know it is not that simple and often do not have the funding for completely replacing equipment that is still functional. The VGA standard still needs to be supported along with the new HDMI.
Here is the solution that is currently working for our classrooms on a limited scale:
As mentioned I have been using Miracast for over a year now with great success. I have been using the Netgear PTV3000 miracast receiver that has a street price of approximately $60.
Netgear PTV3000 Link: http://www.amazon.com/NETGEAR-Push2TV-Wireless-Miracast-Certified/dp/B00904JILO/
The piece that was missing is an HDMI to VGA converter that will convert the HDMI signal from the Netgear PTV3000 HDMI port to a VGA signal.
I have asked many others if they knew of anything that would work and a few mentioned HDMI to VGA converters in the $150 plus range. Some thought that would work with miracast but I found no one that was actually successfully doing this.
Once again my curiosity got the best of me and I found a HDMI to VGA converter for approximately $20 on Amazon that was worth a try to offer a proof of concept.
Below is a screenshot the HDMI to VGA connector I purchased from Amazon.
Amazon link: Note: The link has been removed to Amazon as this unit is no longer available at Amazon 9/29/2014 tg
It is a simple device that takes the HDMI signal from the miracast receiver and converts it into VGA video signal and it also supports sound output if needed.
Here is how I have it connected in combination with the Netgear miracast receiver. I first plug the HDMI cable from the Netgear PTV3000 into the HDMI to VGA converter and on the other side I plug in the VGA cable that goes back to the projector. Next I connect the sound jack to the sound system using a 3.5mm jack.
Click on the image to enlarge.
Every one of our classrooms has a video switch box that supports a VGA connection to the projector so I just use the VGA laptop connector to make the connection back to the VGA projector that is mounted on the ceiling.
This small twenty dollar converter just converts the HDMI miracast video/audio signal into a VGA signal and separate audio signal. The VGA signal is sent to directly to the projector and the separate audio signal is sent to the sound system. This little box was the missing piece that now allows the wireless miracast signal to be converted to VGA and a separate audio channel.
Here is where the magic happens, since you now have an active Netgear PTV3000 miracast receiver you can pair your Windows 8.1 or Android tablet (the device must support miracast) and walk about the room while wirelessly displaying (mirroring) what is on the tablet screen up to the VGA projector.
Click on the image to enlarge.
If you also want sound you will need to buy a little “pigtail” adapter that allows you to plug in a 3.5 mm sound jack from the HDMI to VGA converter to your sound system. Below is a picture of a pigtail that converts the Red and White RCA jacks to a standard stereo 3.5 mm female adapter that you can plug-in to your speakers or sound system.
Both the miracast receiver and the HDMI to VGA converter require an electrical outlet so make sure electrical power is available near where you plan on connecting to the projector. I have been using a surge bar to plug-in both the Netgear miracast receiver and HDMI to VGA converter power adapters. This way I can turn on both devices using the on/off switch once everything is connected.
I recommend connecting the VGA connector and sound jack first and then the HDMI cable into the Netgear PTV3000 BEFORE you connect the power adapters. I have gotten some feedback (loud buzzing sound) if the Netgear is plugged in and there is no power to the HDMI to VGA converter.
Works on Android too!
I have also tested this on a colleagues Nexus 7 tablet (2013 model) running Android 4.4.2 and it works! Curiously the Nexus 7 did not require you to punch in a number code to connect like I have had to do with Windows 8.1 tablets. I tried it with my Nexus 7 2012 model but unfortunately the 2012 model does not support miracast L
I have noticed some stuttering with the sound, especially in the beginning of playing back YouTube videos, but overall this solution is working well with our VGA projectors. The video looks great and the lag is minimal. This is a very workable solution for classrooms. I am a little concerned if such an affordable converter ($14) will last over time but so far it is performing well. With electronics if something is going to fail it generally does so within a few hours of use.
These are early days for wireless projection systems so more testing is needed to verify the robustness of this technology to see if it can withstand the day-to-day demands and reliability needed in the classroom.
I have a small netbook case that I use to store the components that makes for easy traveling. This kit easily fits into a laptop bag and you now have the capability of connecting to a VGA projector wirelessly on the road.
I have a small netbook case that I use to store the components that makes for easy traveling. This kit easily fits into a laptop bag and you now have the capability of connecting to a VGA projector wirelessly on the road.
Note: There are also projectors on the market that offer wireless display technology built into the projector/HDTV. This is an area that is moving fast and the good news is the standards are becoming more mature and reliable.
What was once a stumbling block is now a stepping stone, instead of spending thousands for new projectors this solution will work for those facing budget issues. The good news is that for approximately $80 you can convert a VGA projector to a wireless display and continue using your established equipment until the time comes to replace it with the latest and greatest. 4K displays anyone?
What was once a stumbling block is now a stepping stone, instead of spending thousands for new projectors this solution will work for those facing budget issues. The good news is that for approximately $80 you can convert a VGA projector to a wireless display and continue using your established equipment until the time comes to replace it with the latest and greatest. 4K displays anyone?
Keep on Learning,
Dr. Grissom
@tomgrissom
0 komentar:
Posting Komentar