- Tue Jan 04, 2011 2:05 am
#116573
Simple idea for my home - what I have is several input audio sources (stereo phono leads) that go to my sound system that accepts just a single stereo phono. At the moment I have to keep swapping the wires over. What I want is an automated switch.
Only one sound source should be active at any one time (and even if there are more it doesn't really matter) so it should automatically pick the first active input it finds and send it to the output.
One additional little thing I would like is a remote volume control as my system doesn't offer that either.
The Idea
=================================
What I presume I can do is have a voltage level detection circuit for each input to determine if a line is active or not. I could do this with a uC or an actual voltage detector to fire a high to the uC on detection removing the need for ADC of the uC, but adding cost to the project. I presume the line inputs are 0-1V amplitude so I should look for say 0.3V or higher assuming that if the level remains lower than that for 10 seconds that the line is not active.
Presuming that would be a viable solution I would use an analogue switch to effectively pass the active line straight back out to the output line. Again any suggestions on better approaches are welcome.
With the auto-switching done, I would like to add a sort of volume control to the output. I can sort out the IR remote or wireless no problem, so it is just left as how to attenuate the output via the uC or similar to create a volume change. Not really sure where to start with this?
Only one sound source should be active at any one time (and even if there are more it doesn't really matter) so it should automatically pick the first active input it finds and send it to the output.
One additional little thing I would like is a remote volume control as my system doesn't offer that either.
The Idea
=================================
What I presume I can do is have a voltage level detection circuit for each input to determine if a line is active or not. I could do this with a uC or an actual voltage detector to fire a high to the uC on detection removing the need for ADC of the uC, but adding cost to the project. I presume the line inputs are 0-1V amplitude so I should look for say 0.3V or higher assuming that if the level remains lower than that for 10 seconds that the line is not active.
Presuming that would be a viable solution I would use an analogue switch to effectively pass the active line straight back out to the output line. Again any suggestions on better approaches are welcome.
With the auto-switching done, I would like to add a sort of volume control to the output. I can sort out the IR remote or wireless no problem, so it is just left as how to attenuate the output via the uC or similar to create a volume change. Not really sure where to start with this?