[sdiy] Jack insertion detection

[MTG]

Your original idea sounds fine, just keep in mind that the out of range 
voltage may appear on the incoming tip briefly until the out of range 
connection is broken.


> 
> On Mon, Jul 23, 2018 at 2:21 PM, Tim Ressel <timr at circuitabbey.com 
> <mailto:timr at circuitabbey.com>> wrote:
> 
>     Hello supremely helpful folks!
> 
>     I've got another challenge: how to detect when a plug is inserted
>     into a jack. These are 3.5mm mono jacks btw. The current method is
>     to use a stereo jack. When a mono plug is inserted the ring
>     connection gets shorted to ground by the sleeve of the plug. This
>     method works well, but the stereo jacks are taller than the mono jacks.
> 
>     The only jack I can use is a switched mono jack where switched port
>     is tied to the tip port until a plug is inserted. My idea is to use
>     the switch port to feed an out of range voltage to the tip port,
>     probably a negative voltage. Then use a comparator to detect when
>     the tip port goes high.
> 
>     Any other thoughts?
> 
>     -- 
>     --Tim Ressel
>     Circuit Abbey
>     timr at circuitabbey.com <mailto:timr at circuitabbey.com>