Page 1 of 2 12 LastLast
Results 1 to 10 of 12
  1. #1
    500+ This must be a daytime job 737NUT's Avatar
    Join Date
    Feb 2006
    Location
    Indianapolis, IN
    Posts
    778
    Contribute If you enjoy reading the
    content here, click the below
    image to support MyCockpit site.
    Click Here To Contribute To Our Site

    Latest picture and update on my real 727 engine gauges working

    The EPR gauge is servo driven, Fuel Flow is driven by servo on a pot producing a 0-5Vdc output driving an old gauge set-up from Beta Innovations. The digital mechanical N1, N2, and EGT are driven off the PIC boards Mike Powell and I built and designed. VSI gauge is stock internals with a gutted servo driving the stk dc motor w/ feedback from the stk pot in gauge. All are interfaced thru OC servo cards and SIOC. ALL are working flawlessly now with over 100hrs of operation. The wiring is a little messy as this is a temp set-up in my apartment.
    Attached Images Attached Images

  2. #2
    150+ Forum Groupie twisted8's Avatar
    Join Date
    Jun 2009
    Location
    California
    Posts
    243
    Contribute If you enjoy reading the
    content here, click the below
    image to support MyCockpit site.
    Click Here To Contribute To Our Site

    Re: Latest picture and update on my real 727 engine gauges working

    Impressive! that looks sweet!

  3. #3
    Executive Vice President, MyCockpit


    Matt Olieman's Avatar
    Join Date
    Oct 2005
    Location
    Ocala, FL USA
    Posts
    3,155
    Contribute If you enjoy reading the
    content here, click the below
    image to support MyCockpit site.
    Click Here To Contribute To Our Site

    Re: Latest picture and update on my real 727 engine gauges working

    Impressive Rob

  4. #4
    500+ This must be a daytime job 737NUT's Avatar
    Join Date
    Feb 2006
    Location
    Indianapolis, IN
    Posts
    778
    Contribute If you enjoy reading the
    content here, click the below
    image to support MyCockpit site.
    Click Here To Contribute To Our Site

    Re: Latest picture and update on my real 727 engine gauges working

    Thanks Matt! It sure does enhance the flying on the sim. My next project is the radar altimeter.

  5. #5
    150+ Forum Groupie choffmann's Avatar
    Join Date
    Mar 2008
    Location
    Germany, Hanau
    Posts
    231
    Contribute If you enjoy reading the
    content here, click the below
    image to support MyCockpit site.
    Click Here To Contribute To Our Site

    Re: Latest picture and update on my real 727 engine gauges working

    Hats off! This must be a very subtle and difficult work! Are those gauges original ones, or replicas? They look marvellous! What i/o cards do you use?
    Chris

  6. #6
    500+ This must be a daytime job 737NUT's Avatar
    Join Date
    Feb 2006
    Location
    Indianapolis, IN
    Posts
    778
    Contribute If you enjoy reading the
    content here, click the below
    image to support MyCockpit site.
    Click Here To Contribute To Our Site

    Re: Latest picture and update on my real 727 engine gauges working

    The gauges are the real deal, using SIOC, Opencockpits servo cards, and custom built interface for the digital gauges.

  7. #7
    25+ Posting Member crashdog's Avatar
    Join Date
    Jun 2010
    Location
    swizerland
    Posts
    42
    Contribute If you enjoy reading the
    content here, click the below
    image to support MyCockpit site.
    Click Here To Contribute To Our Site

    Re: Latest picture and update on my real 727 engine gauges working

    Hello,
    my name is Gery and I am new to this forum. I'm building an MD80 simulator with as many real parts as I can get and use.
    www.md80.ch. Currently I'm working on my overhead panel where I have a similar if not the same gauge to interface. I'm wondering if I can use the same approach as you did. But actually I'm not shure if the gauge really has a DC motor or if it's something else.

    Here's a picture of it. It's the APU percent indicator. The same kind of gauges have being used for N1 and N2 as well.
    There are 3 cables coming from the motor one red, one blue and a white one. Possibly this motor is a stepper or aircore ? I also have OC servo cards and also OC stepper motor cards. But would not know how to connect this one. From the pictures of the DC motor card it seames that only 2 cables go to your N1 gauges.?. Hope you could help me on to the right track here...

    Kind Regards,
    Gery
    Last edited by crashdog; 06-18-2010 at 07:34 PM. Reason: corrected link

  8. #8
    300+ Forum Addict Anderson/SBSP's Avatar
    Join Date
    Aug 2008
    Location
    São Paulo, Brazil, Brazil
    Posts
    336
    Contribute If you enjoy reading the
    content here, click the below
    image to support MyCockpit site.
    Click Here To Contribute To Our Site

    Re: Latest picture and update on my real 727 engine gauges working

    Your cockipt is amazing!!!
    Anderson Roberto de Souza - Brazil / São Paulo
    Blog: www.737ngsim.com.br Twitter: @ARSouza

  9. #9
    500+ This must be a daytime job 737NUT's Avatar
    Join Date
    Feb 2006
    Location
    Indianapolis, IN
    Posts
    778
    Contribute If you enjoy reading the
    content here, click the below
    image to support MyCockpit site.
    Click Here To Contribute To Our Site

    Re: Latest picture and update on my real 727 engine gauges working

    Quote Originally Posted by crashdog View Post
    Hello,
    my name is Gery and I am new to this forum. I'm building an MD80 simulator with as many real parts as I can get and use.
    www.md80.ch. Currently I'm working on my overhead panel where I have a similar if not the same gauge to interface. I'm wondering if I can use the same approach as you did. But actually I'm not shure if the gauge really has a DC motor or if it's something else.

    Here's a picture of it. It's the APU percent indicator. The same kind of gauges have being used for N1 and N2 as well.
    There are 3 cables coming from the motor one red, one blue and a white one. Possibly this motor is a stepper or aircore ? I also have OC servo cards and also OC stepper motor cards. But would not know how to connect this one. From the pictures of the DC motor card it seames that only 2 cables go to your N1 gauges.?. Hope you could help me on to the right track here...

    Kind Regards,
    Gery
    You have a Synchro which operates on 400Hz AC power. Don't fret though as it is easy to convert! Remove the rear housing, remove guts of synchro, mount micro servo and use a coupler from servo city or make your own to go from servo to the needle shaft. Piece of cake!

  10. #10
    75+ Posting Member Leo Bodnar's Avatar
    Join Date
    Apr 2008
    Location
    UK
    Posts
    97
    Contribute If you enjoy reading the
    content here, click the below
    image to support MyCockpit site.
    Click Here To Contribute To Our Site

    Re: Latest picture and update on my real 727 engine gauges working

    This is not a synchro and it does not operate on 400Hz.
    The APU % indicator pictured uses 3 phase synchronous AC motor with permanent magnets rotor and unlike synchro uses only three wires.
    Operation is achieved by spinning the motor at a speed proportional to APU speed. The airgap magnetic coupling causes the needle to deflect in proportion to the rotor RPM.
    To drive this and similar RPM gauges you need to supply 3 sinusoidal signals shifted 120 degrees to each other somewhere in the region of 12V or possibly more.
    There is no position or speed feedback (the AC motor works in open loop mode) so you have to figure out what voltage is enough to keep rotor moving up to speeds producing full scale deflection.
    Because you are varying the drive signal frequency make sure you don't use the full voltage for very slow speeds effectively slowing down to have DC voltages on the coils. In such case there is no inductive impedance and motor coils can easily overheat.
    What I mean is that if you find out that motor works reliably to full scale at e.g. 24V AC then don't allow 24V to remain on the coils when APU stops. Cut it off at e.g. 10% speed or ideally you can decrease driving voltage simultaneously with RPMs arriving at about 5V at zero RPMs.

    So this is one of the simple gauges to drive, just excercise a little bit of caution and planning

    Here is a picture of similar one running without any internal alterations. It also demonstrates how magnetic flux coupling works.
    PastedGraphic-2-1.jpg

  11. Thanks arnolde thanked for this post
Page 1 of 2 12 LastLast

Similar Threads

  1. Real VSI+$40+1hour=Working real gauge!
    By 737NUT in forum Interfacing Real Aviation Parts
    Replies: 6
    Last Post: 01-11-2010, 01:35 PM
  2. Engine Gauges
    By mach7 in forum MyCockpit Support:
    Replies: 1
    Last Post: 08-30-2009, 02:32 PM
  3. Gauges not working
    By docmeister in forum Cockpit Software: Miscellaneous
    Replies: 0
    Last Post: 05-02-2009, 07:56 AM
  4. UK Worldflight 2008 Latest :2nd update
    By steveeverson in forum MyCockpit Member Meetings
    Replies: 2
    Last Post: 11-06-2008, 06:38 AM