As the phrase implies, a TV will display "no signal" when it is not receiving an audio or video feed from a device that is connected to it, like a digital cable converter box, DVD player or video game system. As such, there can be many different causes for a TV's displaying "no signal," so it is useful to know a basic troubleshooting procedure for restoring signal to your TV, a procedure that can be applied to Apex or any other brand of TV.
Switch to a different video input by pressing the input selection button on your remote or on the front panel of the TV. The button will most likely be labeled "Input," "Source," "TV/AV" or something similar. Press this button several times to check if your TV is simply on the incorrect input. If your DVD player is connected to Video 3 and your TV is set to Video 2, for example, your TV may very well read no signal even though the DVD player and TV are both working fine. If you determine that you are on the correct input and are still not receiving a signal, some further troubleshooting is required.
Power on the device that you are attempting to watch by using the remote control or the front panel power button on the device. If your digital cable box is connected to the Video 2 input on your TV and your TV is set to Video 2, for instance, your TV will still display "no signal" if the cable box is simply powered off. If you find that your TV is set to the correct video input and your device is powered on, it is now necessary to check the physical cables that connect the device to the TV.
Replug any loose connections between the component device and your TV to see if a loose cable is causing the loss of signal. The simplest way of doing this is to locate the video input connections on the back or side of the TV and trace the cables up to the component device. Check for any loose connections and secure them to check and see if this restores the signal to your TV from the component device.
Connect the component device using a different set of audio/video cables to check for a bad set of cables. If you use RCA cables to connect a VCR to a TV, for example, loss of signal could be caused by the RCA cable's having worn out. Connect a different set of RCA cables in place of the ones currently plugged in to check for this.
Connect the component device to a different video/audio input on the TV. This will check for a possible issue with the input connections on the TV itself. Simply locate the video and audio cables that connect your component device to your TV and move them to a different video and audio input on the TV. If your signal is restored, you may need to have the TV serviced as one particular input connection may have gone out on the TV.