This circuit is from an old Electroics Now. Its purpose is to protect the fax and modem lines of two computers of the time. Suppressors are types of the time.
We found this circuit in the Linear Applications Handbook of the National Semiconductor of 1994....
In the figure we have the use of one of the four existing amplifiers in the LM2900 and LM3900 as a...
Based on components from Linear Technology, we find this circuit in a 2005 manual. The circuit...