, a back-to-back connection
is a direct connection
- the output of a transmitting device and the input of an associated receiving device. When used for equipment measurements or testing purposes, such a back-to-back connection eliminates the effects of the transmission channel or medium.
- the output of a receiving device and the input to a transmitting device.
The term direct may be construed as permitting a passive device such as a pad to accommodate power level constraints.
- Source: from Federal Standard 1037C and from MIL-STD-188
A back to back connection is 2 idenitcal or similar components connected in series with the opposite polarity. This is used to convert polarised components to non-polar use. Common examples include: