When looking for RF cables or connectors the first item you need to identify is the cable. You will generally find 3 types of cable. Coax, Twinax and Triax, each type will then have different variances and sizes.
Coax Cable
Used to transfer Radio Frequency (RF Signals
- Telecommunications
- Computer Local Access Networks
- Video
- Wireless Communications
- Low level RF Signals
Two Conductors:
- Center conductor for signal transfer
- Outer Shield
- Ground, sometimes used for signal return
- EMI/RFI (Electromagnetic Interference/Radio Frequency Interference) protection
Twinax Cable
Referred to as twisted/shielded pair and Twin Axial
Differential data transfer
- High/Low signal – reverse image
- Phase Locking
Non-Differential data transfer
- Signal and clock
- Signal and return
- 78-124 ohm impedance
- 78 ohm primary
Three Conductors
- Center conductor (blue by convention)
- Intermediate
- Outer Shield
- EMI/RFI protection
Triax Cable
Referred to as double shielded coax
- Military shipboard data bus applications
- Video
- Low current Test and Measurement
- 50-75 Ohm
- 75 Ohm primary
Three Conductors
- Center Conductor
- Inner shield
- Outer shield
- EMI/RFI protection
Ribbon Twinax
There also exists a product that is marketed as ribbon twinax, but application is markedly different from above.
This product is used in a variety of high speed (Upwards of 15Ghz) applications include PCI Express and other high-bandwidth multi-channel mediums. It can be found in connector terminated versions, as well as direct solder to board which can be cut to custom lengths and all of which can be folded tightly without major signal degradation.
