HSI output to 3rd party Autopilot

[tonybrixi]

Hi,

I have installed a D100+HS34+D120 Dynon system + GNS430 + TruTrak Sorcerer Autopilot. Everything is working just fine, but one thing.

I'm missing the signal output from HSI to AP, that should be from 0 to +5 V I think. Did I miss something on installation instructions or it is really not there?

Thank you in advance for any help here.

Tony

 

[Brantel]

Not sure but I don't think you will be able to directly connect the HS34 to the DG/HSI input of the TT without some sort of adapter.  The manual for the TT states that an adapter specific to the HSI must be used.  I would say that you will need to contact TT on this. (update: Per Dynon, not possible...unless you can go ARINC429 which will require TT to update firmware. Good luck on that one!)

The only thing connecting the HSI will get you is the ability to set the heading bug to be followed by the TT.  If you don't have it, you can still use the knob on the TT to select the ground track.  Not the same as magnetic heading but better than nothing.

Maybe TT has an adaptor to adapt the resolver output of the HS34 to the AP???? (update: Per Dynon, they do not have a resolver out for HB only for OBS)

 

[dynonsupport]

From what I know, the sorcerer is designed to be hooked to a few, specific, old analog HSI's. We do not provide any outputs from the HS34 that are designed to feed this unit. We do not have a heading bug resolver output.

We do output everything over industry standard ARINC, so a call to TruTrak to try and get them to update their firmware to take ARINC-429 inputs is probably your only option.

 

[Brantel]

Guess you could always send that Sorcerer back, plop in a couple Dynon servos and an AP76 when it is ready and have every feature the Sorcerer can provide and more! All for about $6500 less than the Sorcerer....

 

[PhantomPholly]

Hi,

I have installed a D100+HS34+D120 Dynon system + GNS430 + TruTrak Sorcerer Autopilot. Everything is working just fine, but one thing.

I'm missing the signal output from HSI to AP, that should be from 0 to +5 V I think. Did I miss something on installation instructions or it is really not there?

Thank you in advance for any help here.

Tony

Tony,

The Sorcerer was practically designed to be driven by the 430 - all of it's INPUTS should be connected to the appropriate 430 OUTPUTS.  Setup is clearly explained in the installation manual found here on page 3.

Dynon is not yet (and may never be, as a business decision) set up to drive 3rd party autopilots - it only drives their own servos directly.  Therefore any outputs from the HS34 to the Sorcerer are, as far as I can tell, irrelevant.  However, the EFIS output from the HS34 MAY drive the OBS setting on the 430, which might in turn redirect the autopilot.  You'll have to experiment with that.

The Sorcerer is a fine autopilot; Dynon is also good but is a bit green and in the current generation there is some small concern that an iced pitot tube could cause loss of attitude reference which the Sorcerer would not be affected by (it may have other weaknesses, but they aren't the same weaknesses as Dynon and thus it serves as a true attitude backup).

Hope that helps!

Bill

 

[dynonsupport]

The Dynon HS34 will drive the 430's OBS.

We put out our heading bug on ARINC-429, just not via the old mechanical resolver method. If Trutrak updates their firmware to take heading bug commands from 429, then they can follow our bug no problem.

Ask yourself what happens to a TruTrak AP with airspeed hold when your pitot dies. They're just as tied to pitot as we are. They also claimed no reliance on pitot for years with the ADI but have now revised that statement after someone tested it and found the unit very reliant on pitot.

 

[PhantomPholly]

The Dynon HS34 will drive the 430's OBS.

We put out our heading bug on ARINC-429, just not via the old mechanical resolver method. If Trutrak updates their firmware to take heading bug commands from 429, then they can follow our bug no problem.

Ask yourself what happens to a TruTrak AP with airspeed hold when your pitot dies. They're just as tied to pitot as we are. They also claimed no reliance on pitot for years with the ADI but have now revised that statement after someone tested it and found the unit very reliant on pitot.

Thanks for the update - and I should also have mentioned that you (Dynon) are aware of the potential problem and working on a fix, and also that in any event the likelihood of pitot failure is very small.

That being the case, they both share the same vulnerability and thus the TruTrack provides no direct advantage over the Dynon other than time in the field - and that will quickly change.  In my opinion the Dynon model is ultimately superior as it is software-driven and can be updated by the owner, whereas the TruTrack cannot be changed except to send it back to the factory.  

In any case, both autopilots should represent solid solutions.  Since the OP already has a Sorcerer and a 430W installed, there does not appear to be an immediate overriding financial or features reason which would require him to replace it once he connects the device as specified.

 

[tonybrixi]

I'm back! Pretty hard to give up!  :-/

I have being talking to those guys from Trutrak and found this:

"Sort of right.  For example, an Advanced Flight Systems EFIS can control the Sorcerer's heading through the AFS heading bug.  It uses a bank command (label 121) to control it.  The Sorcerer in GPSS mode doesn't care or know what course it's on, it only follows bank commands."

“Label 121 roll steering, Label 122 and 324 both need to be present for GPSV, Label 117G can also be followed.”

Do the D100's HSI output these labels throughout the HS34's ARINC ?

Thanks.

 

[Brantel]

The Dynon will not drive an external AP...Period.

Here are the lables used with the HS34:

ARINC-429 Labels Transmitted by the HS34

100G : OBS Value

203: Pressure Alt

204: Baro Corrected Alt

210: True Airspeed

211: Total Air Temperature

320: Magnetic Heading

And Dynon said above that it also outputs the heading bug but I am not sure what label that is.

For the Dynon to output 121,122,324 they might as well be the autopilot as this is more than just following a bug.



ARINC-429 Labels Received by the HS34

034G: VOR/ILS FREQUENCY (BCD)

100: OBS Value

173: LOCALIZER DEVIATION

174: GLIDESLOPE DEVIATION

222: VOR OMNIBEARING

 

[tonybrixi]

hi!

It seems very helpfull. I'll do some tests and get back here to report the results, as soon as I can. Not much time to spend having fun these days.

Thanks,
Tony