What was found
SELECTED GEAR UP AFTER TAKEOFF. GEAR HANDLE INDICATED YELLOW AND RT MAIN INDICATED RED (UNSAFE) FOR 10 SECONDS. THEN RED (UNSAFE) LIGHT ON RT MAIN WENT OUT AND (YELLOW) R DOOR LIGHT ILLUMINATED FOR 5 SECONDS THEN WENT OUT. THE GEAR HANDLE ILLUMINATED AGAIN ALONG WITH THE RED (UNSAFE) LIGHT. THE RED (UNSAFE) LIGHT WENT OUT AGAIN AND THE YELLOW RIGHT DOOR LIGHT ILLUMINATED THEN WENT OUT. LANDING UNEVENTFUL. FERRY TO PDX FOR REPAIRS. REPLACED THE PROXIMITY SENSOR ON RT MLG UPLOCK ASSY IAW AMM TASK 32-31-21-000-801 AND 32-31-21-400-801, OPS TEST GOOD. RETURNED TO SERVICE.