Looks like a clock to divide by 1000 and generate 59.99 Hz A computer video card or monitor? Some piece of Video gear? A UPS? A solar system power inverter? A generator control panel? -- Joe Leikhim Leikhim and Associates Communications Consultants Oviedo, Florida JLeikhim at Leikhim.com 407-982-0446 WWW.LEIKHIM.COM