Thanks for your prompt response Mark, I already deleted my question from Amazon to avoid misunderstandings.
About the baud rate, the Arduino Serial Monitor does NOT have the 28800 Option which surprised me initially, it is a drop down box and you can not edit it. I will research more from the Arduino side and will see how to change it probably from the back end.
I liked you idea about testing the reading with a 5v and 0v entry.
Well, when nothing is connected, it works perfectly, I get a row of full 0es.
IO1 analog values: 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
However with 5v, I was able to confirm my thoughts, the first value is the correct reading, however I have no idea where the rest of the values are coming from:
IO1 analog values: 1023 717 728 519 728 519 370 266 718 493 345 241 164 112 67 45
About the schematics, I am just connecting my linear hall sensor to ground and 5v and connect the reading signal pin to the MuxShield, thats it.
The initial prototype without the Mux was working fine with 9600 bauds connected to the Analog0 in my Arduino UNO.
Please note that the above data is still with the 9600 baud setting since I still dont know if it is possible to select 28800 in the Arduino Serial Monitor.
Any other suggestion or test? is there any piece of the code or the library that I can take to make a mini-test with only one of the Muxs, Analog Input?
Thanks in advance for your comments