It turns off in Record Mode or Play Mode.

Same thing happened to me. No display, no menu, no S-video output while in camera mode, but in VCR mode all was OK. Turning power off and on did not help until I also disconnected the AC power adapter. BTW, Mr. Riggins did not read the question before he answered.

You can try first a reset from menu, then , if firmware is available you can reinstall firmware.

check the conections if some where loose.

• Like all the old video recorders there are mechanical parts inside what need cleaning in high priority the parts that mechanical activate switches for the intake in the little microcontactsswitches and the most important of all are mechanical mode-select-switches where timing is an hot issue
  
• The entire process is timed often gears are used, but sometimes also strings that can slip by age and or dirt, cleaning and contact cleaner and look for bad soldering.
• Also check that the lens motor for the aperture setting is working properly, because everything concerns mechanical settings when that failure then stops the device.
  Also the zoom lens motor that are the first mechanical parts after the tape was lace in. all must exactly done in a special short timing.
• 
  

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try cleaning the record head, Most people only clean the play back heads on tape players, the record head is just off to one side of the main playback heads , you can use a Qtip and rubbing alcohol to do the cleaning

to hear the audio fold back in prerecording mode you will need a tape that still has a security tab in it if not put some tape over the whole or even block the hole up

supply the tape unit with a good signal and then hold down the pause button and press the record and play button at the same time. you will then be able to monitor the sound you are about to record. use headphones as this to stops background noise in your ears and allows you to focus on the sound, "its another world inside your cans" adjust the input level until just peaking into the red. when you are ready to record leave the record button alone and the stop button and the play button just release the pause button and away you go. to stop press stop to stop recording say to cut out an advert or something just press pause.

The playback head is dirty. Insert a brand new tape into the drive and perform a record, through the entire tape until it reaches the end. Then play a pre-recorded tape.

I'm going to venture a guess that what might have happened is you changed the mode of recording. VCRs record in either short play, or long play, or even super long play. As the length of playtime goes up, the quality goes down, because for short play, a 6 hr tape will record only two, whereas a 12 hour tape will record four hours. More information is stored on the tape, so the quality of picture and sound increase, but a longer movie could be cut off. You can adjust the play-length with the sp/slp buttons on your remote control.

Tracking is very sensitive on hi-8 tapes in LP mode. This recorder will record and playback in LP mode. It is however recommended that if you record in LP mode that you use the same camera to play it back, that it was recorded with, or you might have problems.
Also from what I can find online, the TR427 is just an video8 camera not a Hi-8 so if you are trying to play Hi-8 tapes on it, it won't play right.

Sometimes that happens to me too. What I do is just push play, then fast forward, and normally if you watch it, the picture starts to come back. Just keep fast forwarding until you can see all of the picture, and you should be fine.