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Vans stall warning board output

KazooRV-9A

Well Known Member
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Will the Van’s stall warning board drive an external buzzer/horn? If so, what buzzer/horn to buy?

If wired to a headset, what resister value have builders used, to control the volume to an acceptable level?

Tnx,
AC
 
However I think I’m over-thinking it. I gather from the thread that the Vans board is only for insertion of a tone into the headset. So that if I want to use a horn it’s just a matter of powering one and letting the switch in the wing turn it on at stall. I think with further review, that the thread actually did answer my question.
A.
 
answers

The micro switch in the wing can be used with a standalone $5 piezo buzzer that is rated for 12V.

I don't know what size resistor would give the desired volume in the headset from the tone generator board. However, an easy way to find out is to do a bench test and connect a 1K variable resistor (potentiometer) to the output in series with the headset and vary the resistance until the volume is right. Then measure the potentiometer's resistance with a multimeter to get the resistor value.
 
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So I’ve breadboarded the tone generator circuit board on the bench hooking the Audio Mixer/Audio input wire directly to a headset for testing, and when I complete the circuit as the wing mounted switch would, I get no tone.
Am I missing something about what to connect the circuit board output to?
 
The tone generator takes any 12V input and it should generate a tone right? The 12V can be from the microswitch at the stall warner or a battery source. I am planning to hook it to my Intercom and I haven't tested out the tone board yet.
 
The reason I didn't get a tone when I breadboarded the Stall warn unit was, that one of the test leads I was using, was bad. Once I threw that one away, and used a good one, I got a tone out of the board into a test headset, no problem!

In testing, I found that a 5K Ohm resistor inserted in line with the output wire, worked well for the volume I wanted into the headset from the Van's stall warning tone board (a range of 3K Ohm to 10K Ohm is probably usable) . I wired it directly to the pilot headphone jack in parallel with the intercom and Com radio inputs.

Finally have it all installed, I was the biggest problem with the installation!
 
IMG_0465(1).JPG


IMG_0464(1).JPG
 
Aviation headset

Glad you got it to work! Just wondering if the test headset in the photo is an aviation headset or a consumer audio headset? The impedance values are different and may therefore require a different value resistor to adjust the volume to the correct level. Thanks for posting what was the solution.
 
That was just a headset I had sitting around. When I tested for the 5K Ohm resister value, I used a D/C Aviation headset.
 
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