VOR CRS with HS34

[ploucandco]

Hello, I have the following system in my rotax 914 Europa:
- D10A as AI
- D10A as HSI, bus master
- HS34
- AP74 with 2 SV32
- Garmin GNS480 connected through the HS34 for GPS and VOR + Baro/Heading/Course. Arinc is in fast mode for the complete system.
I also connected the output of the GNS480 internal SL30 to the serial of the HS34 in order to have VOR ID information and both active and standby bearings.

The whole dynon subsystem runs version 5.5. And the GNS480 runs V2.3. So both latest versions.

I am pretty happy with the capabilities of the complete system. Now my issue: when I punch the CRS knob on the HS34 and I am tuned up on a VOR, instead of getting a full line with the current VOR radial, I get a deviation of some degrees (maybe 5-7) to the right or to the left depending on To/From. This is always reproducible.

I tried with the VOR information coming from the ARINC and the serial. Both give exactly the same results.

Any insight on that?

 

[Dynon]

Are you saying that you can center the needle, but you need to spin the course 5-7 degrees beyond where you should have to for the location? Or that the course needle never aligns, and that you always have a left/right deflection?

 

[ploucandco]

I did a check in flight today (also verifying with a handheld Sporty's SP400). Tuning a VOR, the output of the GNS480 on the D10A HSI and the SP400 do agree. They show a radial within 1 or 2 degree of difference, what is OK. So the GNS480+D10A indication is correct in terms of radial.

The issue is when I push the CRS knob on the HS34, I would expect the HSI to have the line centered and have on the OBS the radial that I am flying. Instead of that, I get a non centered HSI with a 5-7 degree deviation. I can correct that by turning the CRS button to get the HSI centered and so I get radial that I am flying on the OBS, but I would expect that to be automatic when pushing the CRS button.

Am I the only one who is facing this issue?