T-38 HUD Low Voltage Power Supply Unit (LVPSU)

The Low Voltage Power Supply was a major part of the F-16A/B and C/D Head Up Display systems Electronics Unit and variants of that design. The LVPSU takes in aircraft power at 115V 400Hz and 28VDC and conditions it to the voltages required by the internal electronics typically 5VDC and +/-20VDC. The box locates on the opposite side of the EU coldwall from the Circuit Boards such that heat is conducted into that coldwall and cooling is by means of filtered cold air blown through the wall. There were two suppliers of these Power supplies; the majority was made by Eldec in the USA but a number were second sourced from Roband in the UK. The unit has a large ‘D’ type Cannon connector into the EU and externally the Aircraft connector ‘J2’ and most units also have a Test connector ‘1J5’. A more shallow but wider LVPSU was fitted to the F-16A/B whereas that on the F-16C/D type goes the full height of the EU.