Receiver troubleshooting

 In case of having issues with the reception in the model it is needed to walk through several points step by step. Please find below a guideline for this.

In most cases there has been no issue with the VBar Control nor the VBar itself - most issues were reasoned by the model. So please take time and check the points below step by step. In case of sending in a VBar you might also be asked by our service about this list.

So - if you have entries like "packet lost" or "failsafe" in the log we need to dive in. Especially when the "failsafe" message occours in the same log as the flight started - the connection from the model to the radio was still alive, so something disturbed the reception inside the model.

Most issues are reasoned by static glitches or defective motor/cable insulation here. Especially together with humidity and belt driven helis wer urgently need to check the model first.

Please do the following tests and keep a eye on your safety especially when doing tests while the model is running.

The steps below are based on a VBar Control touch / EVO and a VBar EVO. VBar NEO has a little bit different RX panel but works too. VBar Control classic unfortunately does not have the capability to dive that deep into the RX signals, here we use the standard panel for the range check.

Please do this range checks, have a look especially at the "lost packet" Value. It should show >90 Packets receiving. Check the log also for messages during this runs.

Link to the Range Check Article

 

First check - Model is not running - we can detect a basic issue in receiving here.

  • If the receivers internal amplifier was ever hit with static before - we will probably see some low RX bars now. In this case it needs to debug the model urgently and to get the VBar into service.

 

Second check - unmount all Blades - run the model while doing the test - we can probably detect a static issue here. Please do a couple of runs, consider the different humidity on different days.

  • If there is a static issue from the belt drive and also probably a defective motor insulation we will see packet losses in the logs and the packet rate going down. The signal strength bar will not be helpful here - except we have ongoing glitches.

 

Third check - with blades, keep safety! - run the model while doing the test - we can probably detect a defective motor insulation here. Please do a couple of runs, consider the different humidity on different days.

  • If there is a defective motor insulation we will see packet losses and also RPM signal errors (depends) in the logs and the packet rate going down. The signal strength bar will not be helpful here - except we have ongoing glitches.

 

 

Bench tests with a multimeter (belt drive) - here we check the electrical connection between the regarding parts to avoid static hits (belt driven helis).

  • Consider we might have a carbon-look on some models (chassis, tail boom) which isn't already carbon, just colourized resine and glass.
  • Also take note that even carbon parts might not be a good idea to be used as electrical connection. We highly recommend using sperate wires (e.g. old servo wire) to connect the bearing blocks. Especially some Goblins are having serious troble here.
  • On some helis we have a small screw (e.g. Mikado Logo) for a antistatic cable coming sideways through the frame to the tail boom. If the tail moves in flight (what it surely does) and the screw just scraped th surface of the boom only - we might not have a connection anymore. Please ensure it has a good connection even while bending the heli/boom on the bench a bit.
  • It is needed to check all bearing blocks starting from tail rotor gear to the main gear as well as to the motor plate. There should be only a few Ohms resistance "from nose to tail".

 

Visual Bench tests - here we check all wirings manually

  • there should be no defective insulation, especially check the motor wires, they may probably scrub on sharp frame edges and have a short circuit from time to time mid air.
  • also shrink tube used at the connectors between ESC and motor must be checked. Ensure there is no gap between both parts wher a spark could possibly jump over!

 

Bench tests with a multimeter / insulation tester - here we check the insulation. Consider it might require a high test voltage - and sometimes you have to ask a local electrician for this test. Test the motor only - don't have a ESC connected here.

  • In all cases there should be no electrical connection between a motor wire and the motor housing.
  • But if a multimeter confirms "no connection" ths could be different while the motor is running, especially under some load in the air.
  • To get it fully checked ask a electrician to test with a insulation tester. Also turn the motor step by step in between the tests.

 

Motor Insulation Check

 


 

Filing a service case - if you have a result which points to the VBar 

  • You can file a RMA by logging into vstabi.info, then go to your items (left bottom), click on the servie icon of this device in your list.
  • Add the results of the tests done above to the RMA. Otherwise you will be asked from our service to do them first.