Molex KK connector

The Molex KK connector is used in synthesizer by CGS, Cyndustries, EFM, Encore Electronics, Metalbox, Oakley Sound Systems and Synthesis Technology.

Description
The header with pins is usually on the PCB. Inside the housing which mates with it, a metal sleeve is secured each conductor in two places, on the wire and on its insulator. Creating a gas-tight connection between the wire and terminal pin, prohibiting corrosion and the latter forming a strain relief, providing additional resistance to mechanical stress.

Molex KK housings mate with Molex KK headers on the PCB. The Molex headers look very similar to the MTA ones by TE AMP, but they are not the same. Do not try an force a Molex KK housing onto a MTA header or vice versa.

Crimping
A Molex KK socket consists of two parts, a housing and metal crimp terminals. The terminals are bought separately. Generally two different sizes are in use, 0.1” (2.54mm) for signal connections and 0.156" (3.96mm) for power distribution. For 0.100" use wire of 22, 24, 26, 28 or 30 AWG with a maximum diameter of 1.57mm. For 0.156" use wire of 18, 20, 22 or 24 AWG, with a maximum diameter of 2.79mm.

Using the proper crimping tool makes a good crimp joint easy. A properly crimped joint does not need soldering and is more than strong enough. Most crimp terminals are designed to be crimped, not soldered. Soldering a crimped terminal may weaken the mechanical connection, may reduce electrical conductivity, and may damage the terminal. As a general rule, you should not solder a crimp terminal.

Strip about 2 or 3 mm of insulation from the wire. Then with a racheting crimp tool such as the HT-225D. Place the pin into the apropriate crimp tool aperture. Squeeze the crimpers only enough to hold the pin in place. Insert about 3mm of the exposed strands into the pin. Squeeze the crimpers all the way. Release the crimpers, and pull the wire and pin out. The insulation is squeezed by the back of the pin, and the wire is squeezed in the center of the pin. This is to insure good electrical contact and a good hold on the wire. Push the wire and pin into the plastic housing, ensuring that the tab end of the pin goes the correct way into the housing, to lock into the square hole. Using a simpler crimper such as the PA-09 will entail crimping in two steps. First to crimp the conductor then to crimp the insulation.

Mouser Electronics

 * 0.156" 4-pin locking header – 538-26-60-4040
 * 0.156" 4-pin housing – 538-09-50-3051
 * 0.156" crimp terminal – 538-08-52-0072
 * 0.100" 4-pin locking header – 538-22-23-2041
 * 0.100" 4-pin housing – 538-22-01-3047
 * 0.100" crimp terminal – 538-08-50-0114