Summit:
W7O/CE-221
Cellular Provider:
N/A Haystack Butte in Central Oregon is fenced and posted as "Fee Access Only." Don't despair for summits to activate nearby however, as two other accessible peaks are within a few miles. W7O/CE-223 - Juniper Butte right across Highway 97 and W7O/CN-074 - Round Butte, a pavement drive-up a few miles north east of Madras.
I tried three access points to Haystack Butte, the gate at the south was locked indicating that it was not open to the public and the next two roads to the north were posted with the pictured sign.