Have you heard it again Hobbiest? If you search for "night bird" in this forum, a couple of the threads have links to websites with recorded bird sounds. Maybe that will help.
Or maybe you have a mockingbird that has learned to immitate a doorbell or cellphone or something. I've read that they'll do that. lol

Here is a link that might be useful: past threads with night bird

I haven`t heard it since. The mellow tones it made were similar to a middle "C" started note. Kinda sounded like it was played on a flute. Does a mockingbird sing at night? I haven`t heard any do that and we have a bunch here in the neighborhood. After the sun goes down, it gets completely quiet here as far as ANY bird singing, unless it is a hoot owl...and that is rare when I hear them. It was also loud and far off ( 200 yards or so ) I am guessing it must have been a large bird making the sounds. I heard it well from where I was at.

I will check out your link about night birds. I really appreciate the help! :) This one has me tweaked.

Thank you!
:)

Nighthawk?

You can find birds and their calls at the link below.

Here is a link that might be useful: all about birds