[Wid]

I am new to quads and flight controllers. I have successfully assembled and flown a 250 Night Hawk with MT 1806 motors and a CC3D with Coptercontrol. I am trying to set up a lost plane locator beeper that is activated when it receives PWM signal defined as less than -100% on my Taranis+ radio. I have mapped the switch to ch6 and connected the beeper to ch6. I have set extended limits on the Taranis to -125 to +125 as instructed by the instructions that came with the locator. On My planes without flight controllers that is all I need to do and the locator sounds when I send the -125% signal.

I have adjusted neutral position and played with min and max on the  quad with the CC3D.  I don't really understand what I am doing with the neutral adjustments and min/max values as things don't behave as I am expecting. But have gotten the beeper to be always on or always off by messing with those values.

Can I get some help understanding what is going on and how to set up the alarm? I am afraid to do much flying until I have the locator set up.  I used VehicleSetup Wizzard and Tranmitter Wizzard to get going and still have a very shallow understanding.

If I should ask this in a different place please let me know.

Wid (new member)

Oh, the alarm also sound with low voltage but I checked and the PWM signal is above that threshold.

[TheOtherCliff]

If you are using a PWM RC receiver so that each channel has it's own signal wire (vs. anything else where all signals are on the same wire and must be decoded), then the easy thing to do is connect this straight to your RC receiver spare channel, test it by moving the channel to prove that you can turn it on and off, and finally, program your RC failsafe to set that channel to the value that makes it work.

Be aware that most modern RC systems must be programmed to get the switches to do anything.  The default is that the switches don't do anything at all.  Read your RC instructions.

If you are using any other kind of receiver (SBus, PPM, etc.) , you must use the CC3D to decode the signal and put it out as a PWM signal, typically on an unused ESC connection (there are 6 sets of connections and you are only using 4 to actually connect to ESCs).

Set Configuration -> Vehicle ->Accessory0 to the number of the unused ESC connector (probably 5 or 6).  Make sure the Input page and Output page have reasonable values for it.  For PPM Input the values are the same as for PWM Input, 1000 1500 2000 but this might be different for other input protocols.  It should be obvious from the other channels what the new channel should be.  Output probably must have 1000 1500 2000.  See the first paragraph about testing the channel and setting the RC failsafe.

[Wid]

I have it working now

but still unsure about what is going on in the input page. I am using a FrSky Rx connected to the FC by sbus. The Rx does not have PWM output pins. I have Accessory1 mapped to ch6 and set up as the alarm switch. The switch is a 3 position switch and alarm responds as expected, only sounding when switch up. But watching the movement on Inputs page, the middle switch position does not move the graph to the middle, or at all.
I have set min/max to 1000/2000 and neutral to 1500. Switch up only goes to 1811 even though I have 2000 as max. It will only go down to 172 even when min set below that value.  The alarm is working as needed but I want to learn and better understand what I am seeing and why on inputs.

I have flight modes on a 3 position switch and the graph moves as expected with each switch position.

Thanks for the help getting the alarm working. Now I can fly without fear of loosing the quad in the woods. Now I can really learn to fly and tune.
Wid

[TheOtherCliff]

But watching the movement on Inputs page, the middle switch position does not move the graph to the middle, or at all.

That says that there is a configuration issue in the transmitter or even a problem (e.g. bad switch or two switch positions shorted together with a solder blob) in the transmitter.

I have set min/max to 1000/2000 and neutral to 1500. Switch up only goes to 1811 even though I have 2000 as max. It will only go down to 172 even when min set below that value.

As I said, other protocols use different numbers than 1000,1500,2000.  For your simple switch and buzzer, what you have is OK, but you should look at the other input mins and maxes.  From that, the switch should probably be: 172, (1811+172)/2, 1811