var CheckPeriod = (60 * 1000);
var ShowFrom = new Array(9,0,0,0);
var ShowTo = new Array(17,00,0,0);
var PanelId = 'panel-operator';

function CheckForPanelVisibilty()
{
    var objPanel = document.getElementById(PanelId);
    if (objPanel != null)
    {
        var CurrentTime = new Date();
        var ShowFromTime = new Date();
        ShowFromTime.setHours(ShowFrom[0], ShowFrom[1], ShowFrom[2], ShowFrom[3]);
        var ShowToTime = new Date();
        ShowToTime.setHours(ShowTo[0], ShowTo[1], ShowTo[2], ShowTo[3]);

        if ((ShowFromTime <= CurrentTime) && (ShowToTime >= CurrentTime))
        {
            // show panel
            if (objPanel.style.display != 'block')
                objPanel.style.display = 'block';
        }
        else
        {
            // hide panel
            if (objPanel.style.display != 'none')
                objPanel.style.display = 'none';
        }

        setTimeout("CheckForPanelVisibilty()", CheckPeriod);
    }
}