TV working fine an hour ago. Tried to turn it on and got a No Signal message and TV turned off after the 3 minute countdown. Tried again and keep seeing message that TV is in standby mode as no signal for a long time. No response from Home orTV button. V6 seems OK and has white light. Have tried turning V6 on and off with no effect.
Thanks very much for both answers. It seems that somehow the HDMI source had changed - not by me as far as I know - and I found what to do from another answer in the community. Great to have this source of information!!