Here`s a screen of all Security Serv Jammers.
All Jammer Locations
Once a jammer is destroyed, it will reward the player with $2,000 and 1,000 RP. If the player destroys all 50 of them, they will be rewarded with an additional $50,000, totalling $150,000.
The jammers can be destroyed with almost any weapon, and they can be locked on with homing missiles, such as those on vehicles or with the Homing Launcher, making their discovery and destruction much easier.