Description:
The NTE1648 and NTE1649 are bipolar integrated circuits in an 8–Lead DIP type package designed for telephone bell replacement.

FEATUREs:
• Designed for Telephone Bell Replacement
• Low Current Drain
• Small Size 8–Lead MINIDIP Package
• Adjustable 2–Frequency Tone
• Adjustable Warbling Rate
• Built–in Hysteresis Prevents False Triggering and Rotary Dial “CHIRPS”
• Extension Tone Ringer Modules
• Alarms or Other Altering Devices
• External Triggering or Ringer Disable (NTE1648)
• Adjustable for Reduced Supply Initiation Current (NTE1649)

Functions:
• Two Oscillators
• Output Amplifier
• Power Supply Control Circuit