• Set manufacture date unsure but may be 1980
• Dial type: 35Y3D, Date: 10-80,
• Color White: 61
  
  
• BSP for this phone

This is a one line phone designed to work with an operators headset

Headphone jacks


Headphone on off switch


Special circuit board for headphones. Headphone jacks can be seen in lower left


Closeup of top of circuit board


Circuit board lifted to reveal an N1A bell not normally found in 2500 series phones


4228 type network


Terminal board under dial


Wireing diagram