You can connect two TVs with one Set Top Box :)
But same channel will be displayed on both the TVs...
Things you need to connect two TVs with one Set Top Box:
1. HDMI Amplifier Splitter:
There are two types of HDMI Splitter: A. Active (Powered) & B. Passive (Non Powered)
Passive ones are cheap but can work when distance between two TVs is below 6 feet (I have not tried this one).
So if the distance is more than 6 feet, you should buy the Active HDMI Splitter. Like this:http://www.amazon.in/Monoprice-Blackbird-HDMI-Amplifier-Splitter/dp/B01GCGKAAK?_encoding=UTF8
2. A good quality long HDMI cable:
You need a HDMI cable from one TV to second TV. You should buy a good quality HDMI cable like this: http://www.amazon.in/AmazonBasics-High-Speed-HDMI-Cable-Feet/dp/B014I8TRXA?_encoding=UTF8
3. An IR Extender (To make your Remote Work):
Now, If your Set Top Box is equipped with IR Remote, you need an IR Extender to change the channels with remote on second TV. Like this: http://www.ebay.com/itm/Black-IR-Infrared-Remote-Control-Receiver-Extender-Repeater-Emitter-USB-Adapter-/262667423113
The length of such IR Extenders are approx 1-2 meter. So, you can join "similar size cable" (which you can get from any electrical store) in between IR Extender to increase its length.
1. Output of Set Top Box will goto HDMI Splitter.
2. Connect your TVs through HDMI cables with outputs of HDMI Splitter.
3. Arrange IR Extender, so that you can change channels on second TV.
Enjoy watching channels on both the TVs :)