How I get checkbox value when it is uncheck in jquery

Here it's my html code

<tr class="action_table_row">
    <td><input type="checkbox" value="235"></td>
        <td>Location</td>
          <td>
            <select class="delBoyChange">
            <option value="4" selected>ABC</option>
        </select>
    </td>
<td><button class="btn btn-default btn-xs delete_mapping"><span class="glyphicon glyphicon-remove"></span></button></td>

How I get uncheck check box value. I tried...

$( ".delBoyChange" ).change(function() {
    var locationIds = [];
    if($("input:checkbox").prop('checked')){
    $("input:checkbox:checked").each(function() {
    if(this.value != "on"){
        locationIds.push(parseInt(this.value));
    }
    });
    }else{
    alert($("input:checkbox").prop('checked', false).value);
    var locId = $("input:checkbox").prop('checked', false).value;
    console.log("locId-> " + locId)
    locationIds.push(parseInt(locId));
    }
});

to get an unchecked checkbox's value, but I got: undefine

here its my line give me wrong value

var locId = $("input:checkbox").prop('checked', false).value;