Issue with the KX 155 radio stack

AscendedGravity

Posting this here because unfortunately this issue that has been in the other BlackSquare products in regard to the KX155 radio stack and is also in the Dukes. When tuning frequencies above 134.22X a rounding error occurs which will cause various ATC clients (tested on PilotEdge and VATSIM's VPilot) to no longer tune to the correct frequency. For example when trying tune to 134.225 the sim may output '134.224992'.

If the developer would like to reference my JustFlight support ticket, they can via ticket #75995.

Orlaam

In the real world that would be very accurate on a oscilloscope, lol. I hear a lot of GA that sound off by at least 500 KCs. I don't hear that with airlines, so I imagine a lot of GA have pretty old radios that drift over time and are never re-calibrated until it's a real problem. A 132.2249 would sound perfect on AM, if tuned to 134.225. That's a strange finding.

Black Square

Agh, I have revisited 5kHz radio tuning so many times in the past, I thought I finally had it figured out. Sorry that this one is still there. I've created more code tools for myself regarding radio tuning due to the Starship, so I will revisit this again soon and see if there is something I can do. I recall at one point discovering there was an error in the implementation of one of the native radio tuning events, but I can't recall if that was used here. I'll see to it soon. My apologies.

Black Square

Hi All,

I revisited this tonight, and am more confident than ever that there is a bug with the simulator. I am unable to set frequencies over ~134.5 MHz without them losing precision. This is the case in my aircraft, the Working Title aircraft, and even directly from the debugger console. Any aircraft that this works in is either using the events to increment frequencies, rather than set them directly, or setting frequencies from WASM, while I work in JavaScript. While this is something I could create a workaround for in my KX-155 aircraft, it would not solve the problem for the King Air, or Starship. I will raise this internally at Just Flight again, and see if I can bring this to Asobo. Sorry for the inconvenience in the meantime. I wish there was more I could do here.

theegg52

I've done a bit of digging into this and the problem seems to be with SimVar.SetSimVarValue. when using this setting values over 134200000 can trigger the rounding error. after some trial and error i've discovered that using the 'TRIGGER_KEY_EVENT' Coherent call allows all values to be set without the rounding error. Just to add I'm not an experienced coder/programmer just a hobbyist who can bodge things to work as I need them too but hopefully this may help with finding a solution for this issue.

Black Square

Very interesting!! Thank you for taking the time to look into this. I'm having trouble eliciting any response from the frequency variables using my Coherent Trigger library. What parameters did you use with TRIGGER_KEY_EVENT?

@theegg52 said in Issue with the KX 155 radio stack:

Just to add I'm not an experienced coder/programmer just a hobbyist who can bodge things to work as I need them too

Don't worry, I write several thousand lines of code per month, and I still feel this way!

Black Square

Ah, I spoke too soon. I just forgot an import in the new file I was working in.

Brilliant! We have a solution! I'm sure many of my users will be very happy about this. I will roll it out to all my aircraft immediately.

Thank you so much!

theegg52

@Black-Square said in Issue with the KX 155 radio stack:

Ah, I spoke too soon. I just forgot an import in the new file I was working in.

Brilliant! We have a solution! I'm sure many of my users will be very happy about this. I will roll it out to all my aircraft immediately.

Thank you so much!

That's great news. Glad I was able to point you in the right direction.

AscendedGravity

Thank you so, so much @theegg52!