Cole's Series P3900, miniature P.C. termination rotary switch is designed to provide the ultimate mechanical and electrical reliability in instrumentation, industrial controls, medical equipment, aircraft, computers, communication, weapons, as well as ground support electronic equipment.

This P3900 Series switch is designed for high and low level switching, and to meet the requirements of MIL-S-3786 and tested per MIL-STD-202 as follows:

• THERMAL SHOCK PER MIL-STD-202; METHOD 107, TEST CONDITION "B"
• VIBRATION PER MIL-STD-202; METHOD 204, TEST CONDITION "B"
• MEDIUM SHOCK PER MIL-STD-202; METHOD 213
• HIGH SHOCK PER MIL-STD-202; METHOD 207
• MOISTURE RESISTANCE PER MIL-STD-202; METHOD 106
• EXPLOSION PROOF PER MIL-STD-202; METHOD 109
• SALT SPRAY PER MIL-STD-202; METHOD 101, CONDITION "B"

The switches are available with 30, 36, and 45 degree indexing and one to six poles per deck, (see Circuit Diagram).

Unique design construction features include: all terminals on one side, self-cleaning contacts for low level switching and low contact resistance through the life of the switch (25,000 cycles min).

Hardened steel sprocket and ball bearing detent mechanism provide smooth positive detent action and a mechanical life in excess of 100,000 cycles. In the P3900, the terminals and commons are molded in diallyl phthalate thermosetting plastic sealed between decks and between the plastic and the metal terminal with a special process to eliminate flux contamination seeping inside the switch during wave soldering and/or cleaning processes.

Rotors and non-shorting rings are molded of thermo-plastic glass filled to eliminate contamination by transferring plastic particles to the contact system during the life of the switch. The P3900 switch is built in a clean atmosphere, as are all Cole products, to prevent introduction of contaminants during assembly.

These and many other quality features will provide the ultimate in mechanical and electrical reliability, during the life of the switch.