KK2 buzzer to vtx audio help please

[HerkyBird]

I'm building a small KK2 based quad and to save weight I'm not installing an OSD but would like remote battery state monitoring for safety. I have set-up the battery status monitoring on my KK2 with the Piezo Buzzer and it works great but I would like to pipe this back to my goggles via the audio channel on the video link. One way would be to add a microphone to the vtz but that seems clunky, do any of you electronics experts know how I could link the piezo buzzer output (just a voltage pulse I assume) straight to the audio in on the vtx?

[tdmodels]

Hi Grant,  The buzzer on the kk2.0 board is driven directly by 5 volts.  Feeding this into your VTx will not give you any audio.  What you need to do is convert that 5 volt signal into say a 1kHz audio tone at a level of between 1 or 2 volts peak to peak.

I have done exactly this for a friend, using a small microcontroller.  The size of the circuit is about the same as a servo socket connector and sits in line with the two pin connector on one end, for the KK2.0 and bare ends at the other to solder to the audio input cable.  Let me know if you would like one.  Will do it at cost, which is £5.

Cheers,

Tim

[dirtyharry]

£5 is a bargain  :D

Could you stick a 5v LED on there and have it glued just in view of the camera?

[tdmodels]

£5 is a bargain  :D

Could you stick a 5v LED on there and have it glued just in view of the camera?

Of course!

[star]

Hi Grant

I know this is an old thread, that 5v buzzer to audio vtx is perfect for my budget osd :) Anymore?

I have a flip32+ and going to a 200mw 5.8ghz VTX...