What transmitter location has digital power of 570kw?
CREATE TABLE "main_transmitters" (
  "region_served" text,
  "ch_1" text,
  "on_air_date" text,
  "analogue_power" text,
  "digital_power" text,
  "analogue_haat" text,
  "digital_haat" text,
  "transmitter_location" text
);
SELECT "transmitter_location" FROM "main_transmitters" WHERE "digital_power"='570kw';