My shelter does not have a radio station. It doesn't have a Reactor power station either. In fact, I haven't "unlocked" it yet on the menu.

My shelter's population has just hit 61. So, it seems 60 is probably the magic number for when Deathclaws start showing up.

I have my best armed dwellers on the top floor. A normal attack by say 3 or 4 barbarians usually doesn't make it past the vault room where I have two armed dwellers.

My 1st Deathclaw attack had them go through the entire 1st floor and then drop down to the second where the remaining Deathclaws died.... I had 2 dwellers die in the attack.

Most of my dwellers on the 1st floor have their SPECIAL skill sets at at least 5 and LVLs at around 25 to 35.

Also of note... My Mr Handy got in the fight against the Deathclaws and seems to have suffered a little damage. It doesn't look like Mr Handys can be fixed.

Yep, for months i hovered at 60 Dwellers due to game instability with larger populations (which the latest patch seems to have improved upon), so i had a good bit of time to prepare my Vault for Deathclaw attacks. I didn't have ANY Deathclaw attacks at all while i sat at 60 Dwellers for 3 months, despite having 20+ Explorers, although i didn't have a Radio Room. When the first Deathclaw attack occured, i had at least 20 dwellers to max in all SPECIALs, everyone in the Vault had at least Sawed-Off Shotguns, but my only Lvl 50s were the two guards in the Vault Door room.

My first Deathclaw attack occurred after i updated to 1.2, and i got Piper and 4 Rare Dwellers from the 5 Lunchboxes, which pushed me to 65 Dwellers. I did fairly well on the first attack, only 2 died (due to dwellers stacking on each other so i couldn't heal), and the Deathclaws only made it to the second level.

The second attack was pretty bad. I was lagging horribly during it and menus that i didn't touch were popping up, so the Deathclaws killed a good portion of my first floor, before being killed on the second floor.

The third Deathclaw attack, i smoked them. I had 2 Lvl 50 guards with a Hardened Minigun and Guided Missile Launcher in the Vault Door room, and the next room had 6 Lvl 50 guards, whose weapons ranged from 15-19 Damage. The Deathclaws never made it out of the second room.

I get the distinct feeling that all the people whining and rage quitting over Deathclaw attacks, bum rushed their Vault population, and couldn't handle the result. Taking it nice and steady, seems to be the key. Only expand your population, when you can support and decently arm your current population.