Originally, the connector was designed to carry signals of up to 1 GHz in military applications, but the common Type N today handles up to 11 GHz comfortably. More recent precision enhancements to the design by Julius Botka at Hewlett Packard have scaled this to 18 GHz. The male connector is hand-tightened and has an air gap between center and outer conductors.
The N connector follows the MIL-C-39012 standard, defined by the US military, and comes in 50Ω and 75Ω versions, the latter of which is used in the cable television industry.
Take care to purchase the correct type of 'N' plug for your application as there are different models for different coax cables as well as the 50Ω and 75Ω types!
There are some minor differences of internal fittings, the one I'm showing is common but the method for all is very similar.
1. Carefully strip 15mm of the outer insulation.
Slide the gland nut, washer, rubber gasket and clamp onto the end of the coax.
2. Fold the outer braid back evenly over the clamp, trimming off any excess.
Strip off the dilectric leaving 3mm of dilectric between the clamp and the end of the dilectric.
Trim off any excess center conductor, leaving 6mm exposed.
3. Place the pin onto the center conductor.
Carefully apply a hot slodering iron to the pin and, when heated, apply a small amount of solder through the hole.
There should br no gap between the end of the dilectric and the base of the pin.
4. Slide the connector body over the pin until the braid and clamp have 'bottomed out' in the casing.
Carefully slide the rubber gasket and washer down into the casing, followed by the gland nut.
Tighten the gland nut but do not over tighten.