Best shaker. It has all the features I need except for one.
This shaker would be perfect except for one flaw (more below), but it was still the best shaker I was able to find.<br /><br />Features needed:<br />1) Triggers quickly on phone ring (my phone system ringers are unreliable for technical reasons that won't change anytime soon).<br />2) Does not trigger on extraneous signals and/or background noise.<br />3) Stays buzzing (for at least a minute) even if/after the ringing stops.<br />4) Has a backup battery in addition to the AC supply.<br />5) Does not keep buzzing forever if no one is home to reset it.  (Should auto reset after 1 or 2 minutes. Or this delay might be user adjustable.)<br /><br />Surprisingly, I wasn't able to find these features in any other unit.<br />The KBS300RX satisfies the first 4 requirements nicely when used in conjunction with the KA300 transmitter (required).<br /><br />Alas, the shaker, once triggered will keep going forever until the reset button is pushed.  This is great for heavy sleepers but bad for the many calls when no one is home.  It greatly increases wear on the shaker motor and, potentially, could drain the backup battery excessively in a power outage.
Rating: 5 stars