Connectors & Cables

© D. J. McMahon rev 151012

1/4” TRS connectors – (Tip, Ring, Shield) or 1/4” ‘Phone Plug’

Tip Ring Shield (usually ground)

Usually for audio or low-voltage signal applications

3.5mm TRS connectors --

2.5 mm “sub-mini”

3.5 mm 1/4”

TRS connector comparison

Coaxial power connectors -- or “Barrel Connectors”

Used almost entirely for power connection from AC-DC adapters for low-power, low voltage devices.

Over 20 variants on the same design, set by the Electronics IndustryAssociation of Japan (EIAJ).

Typical variants --

2.35 mm 3.00 mm 4.75 mm 5.50 mm

Banana plugs --

.75” spacing

D-subminiature connectors –

Most commonly 9-, 15-, and 25-pin types. 15-pin HD for VGA connections.

Phono Plug

or ‘RCA Connector’

DIN Connectors: Deutsche Institut für Normung

Mini-DIN: 9.5 mm diameter:

DIN: 13.2 mm diameter:

Used in a large variety of analog, digital, and computer applications

S-Video (or Y/C) Connector --

( 4-pin Mini-DIN )

Multi-pin ‘Cannon’ connectors --

ITT-Cannon Corp.

many applications

Molex© connectors --

Jones Connectors (Cinch-Jones) --

Preferred for low voltage, high current signals

Lemo Connectors –

High density, low voltage; very robust

Lemo variants -

XLR connectors –

Audio applications - very robust

( Cannon Corp: X-Type, Locking, Rubberized insulation )

HDMI connector --( High Density Media Interface )

DVI connectors –( Digital Visual Interface )

DVI connector pin-outs:

Coaxial Cable --

Coaxial Cable --

‘Characteristic Impedance’ for coax (Z0) –

whereR is the resistance per unit length, L is the inductance per unit length, G is the conductance of the dielectric per unit length, C is the capacitance per unit length, j is the imaginary unit ω is the angular frequency 2πF

A complex number with a resistive and reactive component. It is a function of thefrequency of the applied signal, and is unrelated to length. The characteristicimpedance of any cable is directly determined by the conductor sizes, thespacing between them, and the type of insulation used.

Most coaxial cables have an impedance of 50 or 75 Ohms at high frequencies.

In order to have maximum signal transfer, the impedance of a coax lineshould match that of the devices it connects.

Video signals, cable TV, closed-circuit TV, etc all have a 75Ω impedance.RG6, RG79, and RG179 are most often used for video, depending on thetype of signal, the distance, power, etc.

F-connectors –

Video - almost exclusively for cable TV

BNC Connector (Bayonet Neill-Concelman)Widely used for RF & video applications

Attaching a BNC – Read the instructions !

BNC’s on RG-179 coax

Various BNC adapters --

‘Barrel’ connectorsfor BNC

UHF connectors for coaxial cable –

PL-259

SO-329

RF applications - esp radio at medium to high power