The T3R only has an HDMI output, which carries a digital signal. If your Sony TV has an HDMI input then, fairly obviously, you simply need an HDMI cable.
However if the only input on your TV set is a Scart one, then you can't simply connect a cable between the two devices because a Scart signal is an analogue one. The only way you can do the job is to insert a little box of tricks in between the two, which converts a digital signal into an analogue one for you. e.g. this would fulfil the role well:
https://www.maplin.co.uk/maplin-hdmi-to-scart-converter-adaptor-1080p-720p-includes-5v-power-supply-5026686001631
(You'll then an HDMI cable from the T3R to that device and a Scart lead to run from it to your TV).
[Note: If you decide to look for a cheaper one somewhere, make sure that you buy an 'HDMI to Scart' model and not a 'Scart to HDMI' one, as the boxes only work in one direction. Further, many cheap models don't come with a power supply, meaning that you need to provide a USB socket and lead to power the box up. The one I've linked to comes with its power supply included in the price].