AV Switcher - help with schematic

lgallair · Post by **lgallair** » Thu Oct 23, 2008 5:33 am

I am attempting to build Ben's solid-state AV switcher and I am questioning my schematic. The LED's light when I flip the switch but there is no video or audio. If I connect a wire from ground directly to any of the "enable" pins, the video and audio comes through and all is fine. Can someone explain what is wrong with my schematic? And maybe provide a correct one. Here's the schematic I made from Ben's instructions ...

Mario · Post by **Mario** » Thu Oct 23, 2008 5:31 pm

Try keeping the pins floating. That is, disconnect them from the 10k resistor so it's not held high. You say that when you connect the enable pin directly to ground it works, right?

lgallair · Post by **lgallair** » Thu Oct 30, 2008 5:27 am

I tried what you suggested but the video/audio signal still did not come through to the TV. Getting a little frustrated at this point, I removed all the resistors and LEDs from the circuit leaving only a wire going from each "enable" pin to its' own switch that connects to ground. This seems to work so I'm sticking to what works. Would have been cool though to have LED indicators. Thanks for the suggestion Mario.