Dude, they did it for an entire town in Manitoba for four years in the 1970s
The experiment did not apply to everybody in the village, but to a small subset of people.
none of the horrors some people seem to love to predict with respect to UBI ever materialized
The experiment did show a reduction in the number of hours worked in the house, as expected.
The experiment wasn't in any way self-sufficient. The funds came from the wider province, and thus the cascade of "fewer people working leading to a loss of tax revenue, making it harder to continue funding the UBI" couldn't have materialized.
This isn't idle speculation: this loss of revenue is the reason why the age at which people are eligible to receive a public pension has been increasing in developed countries.
Lastly, the experiment didn't attempt to measure inflation in the prices of goods and services provided in the village, so we can't tell whether it materialized or not.
How big and long-lasting would a pilot program have to be to convince you that yes, this does work?
I don't know. The specific concerns about the ramifications of a UBI and hasn't been addressed properly by any UBI advocates. I would like future pilot projects to be designed specifically to address them.
That would make it a basic income, but not a universal basic income. Just to clarify the terms.
Something similar to what you are describing is called a negative income tax, in case you want to learn more about that.