Ok let me try this and see if any of you can help. Sony G 70 projector.All was working fine. I replaced the green tube, with a new Sony green tube. All was ok for about 1 hour. Then the projector shut down with error 21,
115v HT supply fault. It took some time but I found an other working PA board. Replaced the PA board but still the same error 21. Put the replacement PA board in a friends G 70 and all is ok. Put the new Sony tube in my friends G 70 and it ran for 4 hours all was ok. Put old PA and old tube back in my G 70 still error 21. What should I look for now.Graham