- Is the source device connected correctly? If so, then try a different input cable. Does the source work when connected directly to a TV screen/monitor?
- The TV may not be compatible with the modulator. CVBS modulators are MPEG 2 video standard and will work with any digital (Freeview) TV or set-top box. HDMI modulators use H.264 video over the DVB-T transport stream. Some standard TV sets support this format and all HD sets will too. If the TV displays a message along the lines of ‘format not supported’ then the TV is not compatible.
- Is the RF output set correctly? Make sure you use the correct frequency if using a modulator with the setting is Hz. To view our channel to frequency conversion chart, click here. If you are using local terrestrial services, make sure the RF channel you are using is not already in use from the local transmitter.
- Signal level may be incorrect. Too much or not enough signal will prevent the system from working. A TV tuner typically will tune to signals between 45dB & 65dB. Check the specification of the model you are using and whether any attenuation (signal reduction) has been applied and work out how much signal is being transmitted. Then work out the cable length(s) taking into account that signal loss is measured at -1.9dB per 10m. Take off 2dB for each connection such as cable join or wall outlet etc. Don’t forget to add any amplification on.