OK. I have changed the dummy data.

more examples, know 25000 instead of 250
calculate the locations first (this is random ints between 0-9)
calculate the signals with a different STD_DEV for each location
There now should be a pattern between locations and signal since they have different distributions.

I am also running the entire training sequence through multiple times using different learning_rates. 1e-4 is the first one that doesn’t make the number explode or decrease (also seems to be the best).
Am I on the right track here?
Am I calculating the loss correctly?
When do I know that the model is good? What does the loss value mean? Do I need to calculate accuracy to know if the model is good?