The HA-1210 Series of quartz crystal oscillators provide enable/disable 3-state TTL compatible signals for bus connected systems. Supplying Pin 1 of the HA-1210 units with a logic "1" enables the output on Pin 5. In the disabled mode, Pin 5 presents a high impedance to the load. All units are resistance welded in an all metal package, offering RFI shielding, and are designed to survive standard wave soldering operations without damage. Insulated standoffs to enhance board cleaning are standard.