Its almost certainly a Ceramic Resonator. 

These are three terminal devices that have a similar function to a crystal when used in an oscillator circuit, but are much cheaper and consequently have poor tolerances. Unlike most crystals, the ceramic oscillator contains built-in capacitors, so the extra pin (usually the middle one) is ground.

The marking `270` will almost certainly indicate 27MHz. This is a very common frequency in TVs - being the reference frequency for both PAL and NTSC video standards.

The `S` could be tolerance information, or it could be a [date code](https://www.murata.com/en-eu/support/faqs/products/timingdevice/ceralock/char/cch0005). As an EIAJ monthly code, `S` would be May 2010 or May 2018. 

There is no manufacturer information, so it won't be possible to find the exact specifications, however something like Murata CSTLS27M0X51 would be a similar type of device.