I think the two channels should be pulled up directly from the 5V. Behind the 120R you only get 2.4V. Pins 1&4 seem to be swapped in your schematic. Regardsdavef21370 wrote:The only schematic I can find is this......which doesn't help much.
I think the two channels should be pulled up directly from the 5V. Behind the 120R you only get 2.4V. Pins 1&4 seem to be swapped in your schematic. Regardsdavef21370 wrote:The only schematic I can find is this......which doesn't help much.