It was made using the network of small, relatively inexpensive telescopes designed to look specifically for planets orbiting bright stars using the transit method.
The array used 4-inch Schmidt telescopes having CCD cameras and automated search routines.
The TrES project discovered a total of five planets in its years of operation.
Note that the discovery papers do not use the "b" suffix typically used in extrasolar planet designations.
TrES light curves of the Kepler field are available at the NASA Exoplanet Archive