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Obs Hsi knob

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The knob is animated off of the default x-plane dataref, nav1_obs_degm (because the knob is mechanically linked to the compass card). The knob should animate any time the HSI OBS rotates.   The GPS/VLOC should have no bearing on the knob animation of course....  Those commands animate the HSI knobs for me no matter what mode (VLOC/GPS) I'm in, so I can't confirm what you're seeing.

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Posted (edited)

Hello Tom,

To map this knob to the Bravo, you need a separate variable for "increase" and "decrease". When in VLOC mode, the command "sim/radios/... up and down" allows me to change the course of a VOR in the HSI. But in GPS, the knob doesn't rotate to tune the CRS of the HSI according the course of the GPS, I have to do it manually. I tried to use the "nav1_obs_degm", but it doesn't work : a messager of the Honeycomb Configurator indicates that I have not the good value for this variable and so will ignore it. That's why I thought that I need a value to use this dataref through the configurator, allowing the rotary knob the Bravo to animate the knob of the HSI when in GPS mode.

Edited by danhenri
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Hi Tom,

The above discussion touches on the issue I'm seeing so I'm replying on this topic.

I am using the 5 bladed GNS model and when I load a flight plan into the GNS530 and fly the plan, I find that in GPS mode the HSI CDI will react correctly as the next GPS active leg is sequenced, but the OBS course setting the course needle points to will not automatically update to the track of the new active GPS leg. The OBS knob must then be used manually to set the new track (even with the GNS530 in GPS mode).

I have a hardware mapping to the OBS knob which works correctly using GoFlight RP48 rotary, however I expected that when the GNS 530 is in GPS mode the OBS indication is completely slaved to the track on the active leg (including auto sequencing to the next leg and any manual attempts to change the OBS course with the hardware or VC OBS knob while in GPS mode should be ignored). Right now the OBS course can continue to be changed with the OBS knob whilst in GPS mode. I expected this to only be possible when the GNS is in VLOC or OBS mode.

Thank you.

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In modern equipment, I believe this is the case.  The GLASS version should do that. ...but to my knowledge, the OBS on the old RD-550 HSI is a manual setting and is not slaved to anything.  There is a specific option in Planemaker to automatically slew the OBS to the desired track of the OBS...but I have not selected that option for the OEM / GNS variants because of this old unit.  (The RSG G500 requires it however).   As such,  it can be adjusted at any time.  If the OBS on this old unit can be servo/clutch driven, then I am unawares of such functionality on it.  

Also, when the 530 is in GPS mode AND OBS is selected on the 530....then the HSI knob can be used to input an intercept bearing to a waypoint.

As far as the HSI OBS not adjusting in GPS mode as Daniel mentioned origninally, that has been fixed for the next update.



Edited by tkyler
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