Results 1 to 8 of 8
  1. #1
    Boeing 777 Builder


    Kennair's Avatar
    Join Date
    Jan 2007
    Location
    Perth, Western Australia
    Posts
    730
    Contribute If you enjoy reading the
    content here, click the below
    image to support MyCockpit site.
    Click Here To Contribute To Our Site

    Question 5 Digit Com Radios

    After reading Matt's review of the Cockpitsonic Avionics (a beautiful piece of kit and also well reviewed I might say), I noticed that the Com radio has 5 digits instead of 6 (2 decimal places not 3). Although here in Aus we don't use 3 decimal place frequencies other parts of the world do, so how do you overcome the shortcomings when sim flying with this radio of tuning a freq such as "132.125" with only 5 digits?

    I know other versions such as Flight Illusion also produce 5 digit however companies such as Opencockpit produce their Com radio in 6 digit format. What exists in the real 737?

    Thanks,

    Ken.
    Opencockpits | Aerosim Solutions | Sim-Avionics | P3D | FDS | FTX | AS16 | PPL | Kennair


  2. #2
    500+ This must be a daytime job
    Join Date
    Nov 2005
    Location
    rotterdam, the Netherlands, Europe
    Posts
    804
    Contribute If you enjoy reading the
    content here, click the below
    image to support MyCockpit site.
    Click Here To Contribute To Our Site

    Quote Originally Posted by Kennair View Post
    I know other versions such as Flight Illusion also produce 5 digit however companies such as Opencockpit produce their Com radio in 6 digit format. What exists in the real 737?
    6 digits

    CPflight also has 6 digit radios

    Stef
    www.boeing737ng.com
    ___________________________
    The Dutch 737 Simulator Project

  3. #3
    2000+ Poster - Never Leaves the Sim Michael Carter's Avatar
    Join Date
    Oct 2006
    Location
    Southern Illinois, USA
    Posts
    2,887
    Contribute If you enjoy reading the
    content here, click the below
    image to support MyCockpit site.
    Click Here To Contribute To Our Site

    Old style analog Collins and Gables all used five digits too. Since the frequency band is based on 25 Khz spacing, you didn't need to worry about whether you were on the right frequency.

    Your last digit was always a 5 or 0.

    If they haven't already, Europe or at least the UK was supposed to implement a 8.33 Khz frequency spacing above FL245. I haven't heard much lately about this and don't know if it's in widespread use, if at all.

    This would make most current US tranceivers obsolete.
    Boeing Skunk Works
    Remember...140, 250, and REALLY FAST!

    We don't need no stinkin' ETOPS!



    Powered by FS9 & BOEING

  4. #4
    25+ Posting Member
    Join Date
    Aug 2008
    Location
    oslo, norway
    Posts
    62
    Contribute If you enjoy reading the
    content here, click the below
    image to support MyCockpit site.
    Click Here To Contribute To Our Site

    yes, up until not many years ago, 25kHz-spacing made it unessecary for the sixth digit. The frequency "126.05" was with a leading "0" at the end. (050).
    Or 127.75.
    But now it is "126.055", (but I can't figure how this can be a 8.33 KHz spacing,
    it sounds more like a 5KHz spacing to me.)
    So when Fs11 or FS12 evolves, many cockpit builders have to add another digit to their radios.

  5. #5
    2000+ Poster - Never Leaves the Sim Michael Carter's Avatar
    Join Date
    Oct 2006
    Location
    Southern Illinois, USA
    Posts
    2,887
    Contribute If you enjoy reading the
    content here, click the below
    image to support MyCockpit site.
    Click Here To Contribute To Our Site

    It's not just another digit that has to be added, the frequency step must also be changed.
    Boeing Skunk Works
    Remember...140, 250, and REALLY FAST!

    We don't need no stinkin' ETOPS!



    Powered by FS9 & BOEING

  6. #6
    25+ Posting Member PascalHaldenstein's Avatar
    Join Date
    Feb 2008
    Location
    Zurich - LSZH
    Posts
    57
    Contribute If you enjoy reading the
    content here, click the below
    image to support MyCockpit site.
    Click Here To Contribute To Our Site

    Guys
    don't know if this helps but here in switzerland or in general europe I often listen to the radar and there some frequencies have a sixth decimal. for example:Zurich tower: "american 55, contact departure on 135.675"

    I think here in europe the sixth decimal is pretty often used. but I don't know about us territories.
    ....just an idea
    Pascal Haldenstein
    B738 Builder
    My Site:www.pascalhaldenstein.webs.com

  7. #7
    2000+ Poster - Never Leaves the Sim Michael Carter's Avatar
    Join Date
    Oct 2006
    Location
    Southern Illinois, USA
    Posts
    2,887
    Contribute If you enjoy reading the
    content here, click the below
    image to support MyCockpit site.
    Click Here To Contribute To Our Site

    The whole frequency will always be stated, even if it's not visible on the radio head. .675 is still using a 25khZ spacing.
    Boeing Skunk Works
    Remember...140, 250, and REALLY FAST!

    We don't need no stinkin' ETOPS!



    Powered by FS9 & BOEING

  8. #8
    25+ Posting Member
    Join Date
    Aug 2008
    Location
    UK
    Posts
    72
    Contribute If you enjoy reading the
    content here, click the below
    image to support MyCockpit site.
    Click Here To Contribute To Our Site

    8.33 Khz spacing is used extensively in the UK and French upper airspace regions. In fact the UK is currently making more use of it as more and more a/c are equipped with it as standard. It is necessary for commercial a/c to have this in these areas.

    The 'channel' (as they are called) digits are rounded and so do not appear as 8.33 steps, but that is what they are.

    hope this helps a little...

    Skywatch

Similar Threads

  1. digit display voltage
    By Jackpilot in forum General Builder Questions All Aircraft Types
    Replies: 4
    Last Post: 01-21-2009, 01:48 PM
  2. 1 digit input to 2 offsets?
    By sweker in forum FS2Phidget Users
    Replies: 3
    Last Post: 09-24-2007, 08:31 AM