I gotta be kinda subtle about things since I know my players read the forums, so I'll spoiler this.
He's a college professor. As such he is expected to deal with computer databases, student records, etc. Granted, he can get TA's to do that, and things like refusing to use a word processor and instead using a typewriter can just be written off as eccentricity, but he'll still occasionally be expected to handle computers or--god forbid--cell phones without causing explosions.
In power, he straddles the line between a focused practitioner and a full-on wizard. He's got the Sight, constitution, excellent thaumaturgy and several refresh worth of refinements on it, but he has no evocation or channeling. When it comes to "fast" magic, he just can't do it. This fact is what's kept him out of White Council membership (and he has applied), while his magical activities have caused him difficulty in his professional life beyond simply causing computers to blow up (long story worthy of another thread).
He doesn't have Evocation/channeling so you probably shouldn't compel his hexing based purely on emotional states the way Harry often has happen. Occasionally compel him with the destruction of personal gadgets that are still on his person when he is actively casting a spell (ones not on his person should mostly be safe, assuming they are outside the physical circle). Occasionally compel him with the disruption of computer equipment while he has active spells on his person. Without Evocation/Channeling you can't intentionally Hex.
Basically, I think the way I would do it is play the character off as being a bit technophobic (I hope he's a historian, rather than a nuclear physicist!). As you suggested, he could have a TA do all of the data-entry stuff. He doesn't like cell phones, and uses only land-lines. If asked about his eccentricities, his response could vary from semi-truthful ("Oh, I always have bad luck with those gadgets; they always break on me") to conspiracy-theory ("You know that with those smartphones, They can track you down wherever you are, and insert aps that allow them turn on your mic remotely and listen in to what you're saying, right?")
Since he's not a full wizard (and especially since he doesn't do evocation), he can probably get away with some exposure to technology. But to throw out numbers, he probably shouldn't be using any devices designed in the last 5-10 years. Maybe he could keep an older model cell phone working, maybe -- but smartphones should be a nonstarter. Casual computer use might be doable, but consider that even non-wizards get blue screens from time to time, and the resulting frustration would likely result in fried circuitry.
At least, that's the way I'd look at it, YMMV.
Sanctaphrax makes some good points. For all we know, Carlos Ramirez has a cell phone and plays World of Warcraft when he's not out being a Warden.
That being said, when the complications of having a computer fail on him would be significant enough to be worth a fate point, feel free to use that compel.
There may be cases in which the accidental hex might cause complications for everybody, including the opposition. A possible example would be the character might unintentionally hex the lights out inside a building, at night, in the middle of a fight. Assuming that the wizard in question, his allies, and the opposition all lack the means to see in the dark (i.e. no night vision goggles, no Supernatural Senses, no shapeshifting into an animal which sees in the dark or relies on smell and hearing enough to not need to see) it may not be worth giving the player a fate point since you haven't really inconvenienced him... the playing field is still level. In those cases you might want to try something besides a compel. If he fails a control roll on a spell and doesn't take all of the extra shifts as backlash, maybe the fallout hexes the lights. Or, in the absence of fallout, call for a roll on his Discipline. Determine a difficulty to not accidentally hex something and if he fails, it gets hexed. I don't recommend that you use the rolling Discipline method too much, simply because I really prefer to use it as a compel or as fallout... something about those methods is just really satisfying somehow.
Also:
Based on the description I'd recommend the following:
He doesn't have Evocation/channeling so you probably shouldn't compel his hexing based purely on emotional states the way Harry often has happen. Occasionally compel him with the destruction of personal gadgets that are still on his person when he is actively casting a spell (ones not on his person should mostly be safe, assuming they are outside the physical circle). Occasionally compel him with the disruption of computer equipment while he has active spells on his person. Without Evocation/Channeling you can't intentionally Hex.
Probably not necessary, but spoiler tag incoming.
Your Story page 258 explicitly states that Evocation is not needed to deliberately hex and that any spell caster can do it. I say, compel away.