I just got a CB installed in my truck the other day and it got me thinking, in a shtf scenario, what communications would still work? I know portable hand-helds would work but their range is limited. Would cb's, hams, etc still operate?
Depending on the scenario CB, Amateur Radio, FRS/GMRS radios (walmart handhelds) etc... will still operate. Since these radios are infrastructure independent (ie..cell towers) they will continue to operate until you can no longer feed them with electrons. That said, a large scale EMP or large scale jamming operation could hinder their operation/functionality (determine on your own the likelihood/effects of such an event).
(opinion section)
The other thing to consider is the popularity of band/radio. Almost everyone has a CB in the attic/basement and 37 of those walmart handhelds scattered around the house. Having experienced a communications down/saturated event twice in my lifetime, CB and FRS/GMRS were absolutely useless. Everyone and their brother and mother-in-law was yacking. Getting emergency traffic through was near impossible. Consider that there are 40 channels on CB, and depending on the WM Handheld 50 channels. Consider the population density where you live. Assuming two operators per channel (frequency in use), that's a total of 180 people that can communicate at once. Now consider that CB can be fairly long range depending on conditions. Add those folks to the pool of potential users.By now you should be able to deduce that I'm a Ham. But I'm also a prepper, and I have weighed my communication options and have all of the above mentioned methods of radio communications. It's better to be prepared, than scared.
As Krogo mentioned, barring a major EMP event, pretty much all radios would work as usual. Heck, even post EMP, a large number of radios would likely work fine (and with much less interference!).
For SHTF, especially when the "S" is unspecified, it is best to think in layers and redundancy. Cell phones, text messages, email, IM, land-line, radios (CB, FRS/GMRS), ham, smoke signals..... If one service goes down, you can fall back to another.
While you are weighing options (and you should be PREPARED to use any of them) keep in mind that unlike CB and FRS, Ham radio operators often have repeaters in place to increase the coverage area of a handheld radio. Most of the hams have contingencies in place for power failure, disaster, etc.
I personally keep a stash of radio equipment in a shielded metal (grounded) storage box to protect against EMP issues. Just rotate the batteries out regularly with the day-to-day equipment.