• Free Delivery Islandwide

  • 2-year warranty

  • 7-day returns

  • Sign up and save


Shopping cart

There are currently no items in your shopping cart.

    Get exactly the support you need
    Looking for specific solutions for your product?

    What is FSK/DTMF and why do I need it?

    FSK (Frequency-Shift Keying) and DTMF (Dual Tone Multi-Frequency) are data transmission formats that carry caller information.

    General information

    DTMF transmits the caller’s number. FSK is a more recent format for the transmission of caller’s number (or caller’s number and name depending on the network).

    Caller ID service depends on these data transmission formats being supported by the phone. In addition consumers need to subscribe to these services with their service provider.

    Additional information: There are two types of caller information detection. The first type, type I, refers to caller ID detection when the phone rings from standby mode. Type II is the caller ID detection when the phone receives a second call during talk mode. Type II service may require additional subscription with the service provider.

    The information on this page applies to the following models: D4601B/90 , M7701B/90 , M5601WG/90 , M3451B/90 , D1301B/90 , D2302B/90 , D2301B/90 , M6601WB/90 , XL4901S/90 , D4502W/90 , M3301B/90 , M3301W/90 , D1201WA/90 , D1201B/90 , D1202B/90 , M8881W/90 , X200B/90 , D1501W/90 , CRD150B/90 , M8881B/90 , CRD150W/90 , D4001C/90 , D4002C/90 , D4001O/90 , D2003B/90 , XL3002C/90 , XL3001C/90 , D4001B/90 , D4052W/90 , D1502W/90 , D2001WT/90 , D2001WP/90 , D4002B/90 , D4002W/90 , D1501B/90 , D2002W/90 , D2002B/90 , D2001W/90 , D2001B/90 , D1502B/90 , D1503B/90 , M5501WR/90 , D4001W/90 , M5501WG/90 , S8A/90 , CD1901BB/90 , CD1901WB/90 , CD2901W/90 , CD1901B/90 , CD1902B/90 , CD4901B/90 , XL3901S/90 , CD4902B/90 , CD2851W/90 , CD4802B/78 , CD2801W/90 , CD2852W/90 , CD2802W/90 , CD1802B/90 , CD6801B/90 , CD2851W/78 , CD1801B/90 , CD1802B/96 , CD4802B/90 , CD4801B/90 , CD4801B/96 , SE1712B/90 , SE1711B/90 , CD2701S/90 , CD2702S/90 . Click here to show more product numbers Click here to show less product numbers

    Register your product
    Register your product

    Keep track of your product warranty coverage

    Qualify for cash-back, gifts and special offers

    Get easy access to product support

    You are about to visit a Philips global content page

    You are about to visit the Philips USA website.

    Our site can best be viewed with the latest version of Microsoft Edge, Google Chrome or Firefox.