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  • hueysds Level 1 Level 1 (0 points)

    Finally got to try this out and am happy to say that HDMI to VGA with 100 Ohm 1/2 Watt Carbon-Film Resistors worked with the tutorials above. I now have my new Mac Mini Media Center airplaying to my Apple TV.


    Now I need to add some AppleScripts to get the system to turn on airplay automatically through my home automation software! Awesome! Thanks for all the help!

  • ScutterOz Level 1 Level 1 (0 points)

    Hey that's great news. At least I know when I need the thunderbolt connector for something I can replicate this with the hdmi.


    Thanks for the update.



  • jonmichaels Level 1 Level 1 (0 points)



    What did you use to get your setup working? Can you give more specifics?


    I have a new Mac Mini with an HDMI port. It comes with an HDMI to DVI cable. That works fine for plugging in my old Cinema Display monitor.


    I also have several DVI to VGA adapters from old Macs.


    I figured I was all set. I went to Radio Shack and bought a pack of 100 Ohm resistors for $1.20. Bending and sniping was easy. When I went to plug it all in, I discovered my error.


    The HDMI to DVI cable from Apple is DVI-D also listed as 24+1. 24 pins plus the blade. It does NOT have the extra 4 pins around the blade. It's meant for digital DVI connections like on a Cinema Display.


    The adapters I have are all DVI-I to VGA, also listed as 24+5. 24 pins plus the blade and 4 additional pins around the blade. That's an analog adapter which makes lots of sense since VGA is an analog signal.


    However, you physically can't plug the DVI-I to VGA adapter into the HDMI to DVI-D cable since there are 4 extra pins on the first one with no corresponding jacks on the second.


    Poking around online it looks like there are DVI-D to VGA adapters available which everyone complains about saying that they don't light up their monitor. And of course they wouldn't because it would require a lot more than just some pin to pin adapter to convert an analog signal to a digital one. But perhaps they can work for this hack to fake the computer into thinking that there's a monitor attached.


    And that's where my question comes in, is that what you used to get your HDMI to VGA working?


    Like many people here, I would like to do this on the HDMI port and leave the Thunderbolt port open for future expansion.

  does sell a Thunderbolt to VGA adpater for about $13.50 which would probably be my method for doing this if I had to use the Thunderbolt port. I would just stick the resistors into the same jacks as listed on the two links listed above.


    Thanks in advance for your help.



  • hueysds Level 1 Level 1 (0 points)

    Sure, I actually went with an HDMI to VGA adaptor from Amazon for $20:



    And then plugged the 3 resistors into that. Works flawlessly. Plugged it right into the back of the Mac Mini and when I screen shared in got a nice clear screen and was able to push that screen over to my Apple TV via AirPlay. Wrapped up the resistors with some electrical tape so they wouldn't short out in my network closet and wouldn't detach dorm the adaptor.


    My next plan is to write an AppleScript to push the Mac Mini display over to the Apple TV when I push a button in my home automation software:


  • ebcase Level 1 Level 1 (0 points)

    This adapter will work for you as well — &p_id=5969&seq=1&format=2 — combined with SwitchResX if the resolution you want isn't available by default.

    Just make sure to plug in both the thunderbolt and usb cables.

  • ChrisAmbarian Level 1 Level 1 (0 points)

    Hey Guys,


    Arrrgh.  I'm so jealous of those of you who seem to have your setups working...  I've followed the instructions here, and I'm no novice to electronic DIY... and yet, no Airplay yet.  Late 2012 Mac Mini, OSX 10.8.2 Server, works great when connected to my HDTV directly, or through my Denon AV switch / amp.  But when I tried to go headless and to stream via Airplay / ATV, I got the aforementioned pink screen.  So I hooked the HDMI port to the (now unplugged and otherwise lifeless) Denon amp, and voila, Airplay works like a champ.  But wait, there's more...


    So now I know you need to fool the video chip into thinking there's a monitor attached.  So I went out and made a HDMI-->VGA-->dummy plug first with 100 ohm resistors, then with 68 ohm resistors.  (BTW, it's beautiful, with nice solder joints and heat shrink tubing and everything.)  Bleahh.  Didn't work.  In fact, it hangs the video card.  Normally, I can climb aboard my MBA and screen share to log on the server or find out what's going on without problems.  But with the dummy dongle in place, trying to do that results in the following sequence:


    (connect from MBA to server...)


    Connected as Me

    Click Share Screen button

    (extended pause)

    Server doesn't support Screen Sharing encryption.  Connect anyway?

    (yes) --> Authentication failed to Server.  Please try again with different credentials.


    My MBA user is a full admin on both machines.


    Again, everything works normally (or goes back to working normally) when connected to a real video device.


    So now I'm hoping that there's a generous genius out there who knows how much trickier of a plug I need in order to truly fool my Mini into thinking there's a monitor hooked to it.  I can't very well leave a 35 lb stereo attached to my Mac Mini forever...  At least I hope I won't have to...



  • ScutterOz Level 1 Level 1 (0 points)

    Hi Chris


    I'm sorry to hear you're having problems with your 2012 mini. I was hoping that apple would have fixed this problem with the new mini not broken the fix many people seem to use!


    I wish i could say i had a solution for you but i'm affraid i don't. I was working in the dark getting my 11 mini working after putting together the info i found on other websites and making a few lucky guesses.


    The only difference from my work around to what you described was that i used a thunderbolt (or mini display port) to VGA adaptor, rather than HDMI but i know other on this thread have the HDMI variant working.


    I hope you find a solution.



  • hueysds Level 1 Level 1 (0 points)

    Yeah, sorry, I'm no help, I pretty much lucked into this thread and I just followed the tutorial and it worked for me. The tutorial I read said that it could be any resistors between 50 and 150 ohms so I don't think that's the problem. I would say to check the pins you are plugging on the VGA side to make sure that you have the right ones. Basically all you are doing is feeding the VGA signal back on itself so that the Mac mini thinks that it's plugged up to a monitor. I still haven't had any issues with mine.


    Sorry I can't be of more help!



  • ChrisAmbarian Level 1 Level 1 (0 points)

    Hey Huey,


    What vintage is your mini?  I notice that when I hook my Denon amp up as the HDMI load, the Mac Mini is smart enough to identify it as a Denon AMP in the sound prefs.  I'm pretty confident that a stack of resistors isn't going to read back as a HDTV to this video chip... but then again, if you're using the same chip and it works...




  • hueysds Level 1 Level 1 (0 points)

    Mine is the last generation, I bought it in August about a month before the newest ones were released. This is the one I bought on Amazon:



    Model: MC936LL/A


    I've since upgraded it to Mountain Lion server and it's all running perfect.


    Hope that helps!



  • ChrisAmbarian Level 1 Level 1 (0 points)

    Well, that may be a clue...  I've got the latest one.  It has a different video chip in it (Intel Graphics 4000).  It may be more smarter than the older chip... but that's just speculation.  Again, it all works when plugged into my Denon amp's HDMI input, even if the amp's been unplugged and turned off for weeks.


    Anyone else having the same issue?  Does this comport with what you're experiencing?


    I'm thinking now that I need to dummy an actual video chip off of this thing.  Which of course will be worth it in order to have my office the way I want it... but it is a bit more ambitious than I was hoping for.


    Any EE's out there who can suggest a really cheap dummy load to connect to that HDMI port to fool it into thinking there's a real monitor there?



  • philoouu Level 1 Level 1 (0 points)

    If you want to emulate a screen, I have not found any other solution than buying an EDID emulator like Dr. HDMI



    and very light....

  • ChrisAmbarian Level 1 Level 1 (0 points)



    Thanks for your response.  Who knew there was such a thing as an EDID emulator.  I didn't.


    Makes sense, so I went online and bought one to see if it'll work.  I'll report back and let everyone know how it goes...



  • philoouu Level 1 Level 1 (0 points)

    Hey ! no problems I spent weeks to find out... There are a lots of forums about Mini Mac disabling some accerleration "stuff" when headless but I am not sure I completely understoof the issue. In my case this has solved the buggy behaviour of some software that happened with no screen connected.

    Just one thing where you could help me.... You might notice that the stuff you bought when only powered with HDMI will not be always have the blue light switched on and then not remembering properly the EDID. I had to connect permanently the USB cable too to power it properly all the time especially in hibernation mode so that EDID is remembered all the time. It looks like some other guys had the issue too  with a mini mac; I am not sure this is due to the HDMI supply power of the Mini Mac or the TV or the HDMI switch I have also on my case... This is not well documented on the web. Anyway let me know if you need to havd the UBS plugged or not to make it work properly...



  • ChrisAmbarian Level 1 Level 1 (0 points)

    Hi Everyone,


    I am happy to report that at last, I am happy.  My life is now complete.  My MacMini is running headless into my HDTV screen which, for lack of anything better to do, I use as my monitor.


    Thanks to philoouu, I looked at EDID emulators, a world which I did not know existed.  I found the cheapest one I could find on eBay, $50 including shipping from China to the USA.  Most were about $75 to $150.  (Strangely, eBay removed the listing after I paid for it, apparently because of problems with the vendor... nevertheless the converter arrived as expected, and worked the first time.)


    I excitedly tore open the box and slapped the converter into place.  Clicked on AirPlay and... still pink screen.  Despite the fact that the manual says that it needs no external power supply (supposed to be able to drive it with the HDMI connection only), I plugged in the 5V USB cable, and voila!  The blue power light came on, and my screen came alive.  And thus I can write you now. 


    It was only after getting back on this board that I noticed that philoouu had exactly the same experience.  You need the USB power line in order to get the thing working.  The Mini must not supply all that much juice from its HDMI port.


    So in summary:  IF you have a late-2012 or newer vintage Mini, and you want to run it headless but still using AirPlay, and you've got a pink screen on the AirPlayed TV, THEN ignore all the VGA dummy plug posts etc. and find a EDID emulator, and make sure to plug in the USB power as well.  You'll be as happy as me


    Thanks everyone for your help!