SPOILERS
Quotes from
The Nearly Ultimate Fallout Walkthrough (from the Military Base section):
There are four mutant guards around outside the base. If you want to lure three of them away, you can use a Radio, which brings up a dialogue. Say you're being attacked or fell down or something, and you get 1500 xp for tricking the mutants. If they ask for your coordinates, reply with "Four miles, south-southwest". You can attack the three as they're walking off after you got the xp, if you want.
In the room to the right, use Science on the computer that isn't a "Mach IV" to turn it on. Use it (hand icon) until you break the security systems for 800 xp (this is actually a Gambling check, if you can believe it). Optionally use Science on it again until it says you disabled some or all the forcefields, but this doesn't seem to do much. If you use a Radio on this computer (even if you didn't hack it) and pass a Repair check, you can then use the Radio (put it in an active item slot, or it'll work horribly slowly) to toggle all yellow forcefields except on level 4. You can also disable the yellow ones by using Repair on the emitter to turn them on or off, or disable them permanently with explosives. Unfortunately you can't do either to the red ones, and they'll damage you for some 10-30 HP depending on what armour you're wearing (so Dogmeat is fried unless you use the yellow ones to lock him up).