What was found
AFTER TAKEOFF AT 200 FEET AGL FLIGHT ATTENDANT CALLED & NOTIFIED FLIGHT CREW THAT SHE WAS SMELLING ELEC SMOKE & SOMETHING BURNING. COMPLIED WITH AOM ELECT SMOKE & MEMORY ITEM PROCEDURES. IMMEDIATE RETURN TO FIELD & DECLARED EMER. THE ACFT WAS REMOVED FROM SERVICE. TURNED APU OFF, CROSS BLEED AUTO, ENGS 1 & 2 BLEEDS OPEN, PACK 1 & 2 WAS CONFIGURED WITH NO VISIBLE INDICATION OF SMOKE OR FIRE. NO ODOR OF ELEC SMOKE IN COCKPIT. TURNED ON ALL COCKPIT & CABIN LIGHTS FOR OVER FOUR HOURS & COMPLIED WITH ETN-EM-72-034 R9 WITH NO EVIDENCE OF ANY ELEC, OIL, OR PLASTIC ODORS. CANNOT DUPLICATE SMELLS OR ODORS. THE ACFT RETURN TO SERVICE.