AP-74 disconnecting unexpectedly.

[kboyd59]

I just installed the pitch servo in my RV9A. While testing it I was keying my mike on the radio and the AP-74 went dark and the Dynon announced the autopilot had been disconnected, the Ap-74 would not come back on until the error message came up on the bottom of the D-180 that said DSAB Network Configuration Error ACK1. After clearing that message I could turn the Ap-74 back on, this does not happen immediately when I key the mike but when it feels like it.

 

[dynonsupport]

Any chance the radio was dropping the voltage on the power line below 10V, which could shut off the AP74? Are the DSAB wires that go to the any of the products running real near the COM antenna wiring?

 

[Brantel]

If you are getting any kind of harsh noise on or near the DSAB lines, it will swamp the network and take it offline.

Make sure your com antenna is installed properly and you do not have stray RF leaking out near your DSAB lines.

Also, were you xmt'ing inside a hangar?  If so this can cause all kinds of problems with all the RF bouncing around in one.

 

[kboyd59]

First of all thanks for the quick response, second my DSAB wires run with the antenna wire but are in separate plastic tubes, and third I am in my garage so it is very enclosed. So I assume the problem is going to be that it is in an enclosed area.

 

[DBRV10]

And if you can use a shielded twisted pair for the DSAB.

 

[dynonsupport]

Twisted pair for DSAB is considered a requirement, by they way.

I don't think that the garage is going to be the culprit here. If there's an electrical or interference effect, it's going to be a consequence of the way that something is wired, or the tight proximity of some wire to the antenna wires.

 

[kboyd59]

I am not sure what is going on, I confirmed I have power to the servo but now the D-180 dos not see it on line at all.My DSAB wires are twisted, and I did not have the radio on tonight.

 

[kboyd59]

Do I need to update my pitch servo to version 5.4 or do the ship from Dynon updated to the most current version. This servo was shipped to me last week. If I do have to update it will it work if the efis is not recognizing the servo.

 

[dynonsupport]

If it was shipped from us last week, it will have the latest firmware.

If after DSAB configuration, it's not seen as one of the devices you can scroll through, you most likely have a wiring issue of some kind.

 

[kboyd59]

When I first installed the servo and did a DSAB configuration it was recognized right away and had no problem until I keyed the radio mike the other night. I am not sure why the DSAB worked then and now it does not work at all for the servo. Do you have any suggestions as to what I need to look for since the wiring has not changed I am not sure where to start looking. Any help would be much appreciated. Thank you in advance Ken.

 

[jakej]

Ken

There could be any number of reasons why this is happening - hopefully you find a quick solution.
Do you have a disconnect switch on the stick with the resistor 'option' ? If yes then disconnect the yellow wire at the servo end. Reconfigure and try the a/pilot again, let us know the result.

Jake J

 

[kboyd59]

I do have a cut off switch but mine is mounted on the instrument panel just in front of my stick. This switch worked when I initially set up the pitch servo, I have rechecked the wires on the switch and the servo is still not detected, I have disconnected the yellow wire at the servo and it is still not detected, I removed my AP-74 and the DSAB still doesn't recognise the servo.I put a meter on the DSAB wires and the numbers were all over the place, I then metered the yellow shut off wire and the ground wire at the servo plug and I have zero on my meter, I checked the wires that will feed the roll servo and I get the same readings. I guess I need to find out from Dynon what the DSAB numbers should be and if checking the yellow wire and the ground wire at the same time is the correct way to get a reading for the cutoff switch.

 

[dynonsupport]

The numbers that are "all over the place" are DSAB communication. Give us a call or email and we can help you troubleshoot further.

 

[kboyd59]

Contacted Dynon and they advised to send the servo back in for inspection

 

[kboyd59]

Sent my pitch servo into Dynon they advised it was a hardware problem and they could not find anything that I did to cause the problem. I reinstalled the servo and it works fine, and now when I key the mike I have no problems with the AP-74 going off line. I am not sure what fixed this as I have not changed any of the wiring. I will keep an eye on the to see if this changes in the future.

 

[jakej]

Great to hear Ken, have fun

Jake J