IBM 5256-1 Maintenance Information Manual page 14

TPB: Taper pin block.
tractor chains: The parts on the tractor that protrude
through the forms.
transition: Changing from active to inactive or from
inactive to active.
twinaxial: A cable made of two twisted wires inside a
shield.
Vac: Volts alternating current.
Vdc: Volts direct current.
Glossary, Seq.
Affected, Loc ..
Glossary of Terms and Abbreviations 5256 MIM xv