Apple sent us both a Time Capsule and Airport Extreme which I used for testing, but I also purchased a copy of each to tear down and get to the bottom of the changes internally. Before doing that, however, I hit up the FCC to see what I could glean from comparing the test reports between generations. Apparently I wasn’t alone in doing so, as other people likewise picked up on this avenue for finding out what’s different.

Inside the test reports for both are some nice tables that outline maximum output power for the wireless stack inside the devices. I’ve copied and formatted the data for both the Time Capsule and Airport Extreme.

Airport Extreme—Power Output Comparison
WLAN Mode Gen.4 (BCGA1354) Gen.5 (BCGA1408)
2.4GHz—802.11b 286.42 mW 257.04 mW
2.4GHz—802.11g 143.22 mW 307.61 mW
2.4GHz—802.11n (20 MHz) 130.92 mW 257.63 mW
5GHz—802.11a 202.77 mW 326.59 mW
5GHz—802.11n (20 MHz) 164.82 mW 337.29 mW
5GHz—802.11n (40 MHz) 139.32 mW 392.64 mW

Time Capsule—Power Output Comparison
WLAN Mode Gen.3 (BCGA1355) Gen.4 (BCGA1409)
2.4GHz—802.11b 237.14 mW 257.04 mW
2.4GHz—802.11g 143.22 mW 307.61 mW
2.4GHz—802.11n (20 MHz) 130.92 mW 257.63 mW
5GHz—802.11a 202.77 mW 326.59 mW
5GHz—802.11n (20 MHz) 164.82 mW 337.29 mW
5GHz—802.11n (40 MHz) 139.32 mW 392.64 mW

It’s curious that for the 802.11b category power actually went down on the Airport Extreme, but hopefully nobody will find themselves using 802.11b in the first place. Interestingly enough, the results are almost the same on the Time Capsule, except 802.11b power has gone up accordingly. There are different output powers for each wireless mode, including 20 MHz and 40 MHz channels, but on average power between Airport Extreme generations has increased 135 mW, and 143 mW between Time Capsule generations.

Of course the next logical question is whether antenna gain has changed between the two—after all, having a more powerful output power only goes so far. It turns out that both Airport Extreme generations share the exact same antenna configuration and gain, and likewise with the Time Capsule. Note that two antennas are actually shared among the 2.4GHz and 5GHz RF chains—AP2 and AP3 to be exact.

Airport Extreme—Antenna Gain
Antenna Gen.4 (BCGA1354) Gen.5 (BCGA1408)
  2.4GHz (dBi) 5GHz (dBi) 2.4GHz (dBi) 5GHz (dBi)
AP1 - 1.74 - 1.74
AP2 1.41 2.97 1.41 2.97
AP3 2.33 2.67 2.33 2.67
AP4 1.83 - 1.83 -

Time Capsule—Antenna Gain
Antenna Gen.3 (BCGA1355) Gen.4 (BCGA1409)
  2.4GHz (dBi) 5GHz (dBi) 2.4GHz (dBi) 5GHz (dBi)
AP1 - 4.38 - 4.38
AP2 0.1 0.81 0.1 0.81
AP3 0.27 3.09 0.27 3.09
AP4 4.32 - 4.32 -

I hadn’t looked up the Time Capsule antenna gains until now (having not owned one) but it’s surprising how little gain there is on 2.4GHz with antenna 2. I’m a bit surprised that Apple hasn’t moved over to using the antennas from the Airport Extreme in the Time Capsule. The Airport Extreme has a much more even gain configuration between the three antennas, however as we’ll show later performance is relatively comparable between the two products.

Without even breaking the devices open, we now know that the Airport Extreme and Time Capsule both have substantially increased transmit power, and likely share the same radio given the identical transmit power characteristics.

Introduction and Physical Appearances Disassembling Airport Extremes
POST A COMMENT

90 Comments

View All Comments

  • tipoo - Saturday, August 6, 2011 - link

    Oi, I should read slower, heh

    "There’s a stigma that Apple gear is more expensive, and for the 3TB Time Capsule that may be the case, but the Airport Extreme is actually right near where it should be. Take for comparison the Linksys E4200, which is a 2x3:2 device on 2.4GHz, and 3x3:3 on 5GHz, and also Broadcom based. That device runs for $179.99 and features similar functionality including a USB 2.0 port for sharing devices. At $179.00, the Airport Extreme offers full 3x3:3 on both 2.4 and 5GHz, albeit the E4200 does have considerably more Tx power, which we'll investigate in a forthcoming article."
    Reply
  • lowlymarine - Saturday, August 6, 2011 - link

    Calling Caviar Green's "server grade" strikes me as galling even for Apple, who are pretty willing to play fast-and-loose with truth in advertising as it is. Reply
  • repoman27 - Saturday, August 6, 2011 - link

    This odd bit of nomenclature has been around and much debated since Apple first introduced the Time Capsule. WD Caviar Green drives generally offer the lowest price per GB combined with some of the best performance per watt for a 3.5" spinning disk on the market... Just ask Google how many they currently have deployed. So yes, they are ideal for servers.

    What isn't "server grade" in the Time Capsule is the utter lack of redundancy within the device itself. The intended usage model for the TC is as a backup device though, so there is redundancy in the overall system, i.e. you never actually store critical data on it, just a backup of critical data, therefore if it fails it's not much of a problem.
    Reply
  • solipsism - Saturday, August 6, 2011 - link

    Can the Linksys E4200's USB port be used for a printer the way the Time Capsule and AirPort Extreme/Express can? Reply
  • Brian Klug - Saturday, August 6, 2011 - link

    I know it can share attached USB Mass Storage devices, but I'm actually not certain about printers. Jarred probably will talk about it in his review soon.

    -Brian
    Reply
  • ThomasA - Saturday, August 6, 2011 - link

    Does the AE software offer a means to record data usage? With the 'new' DSL caps set by At&t I'd like to be able to compare my info on usage vs. theirs. Reply
  • Brian Klug - Saturday, August 6, 2011 - link

    You could watch the SNMP counters and use one of many software packages (including some big ones like MRTG/Cacti) but that's sort of daunting admittedly. There's nothing in airport utility that will show data use. That's just another thing I leave to Tomato on a WRT54G-TM personally.

    -Brian
    Reply
  • deadshort - Saturday, August 6, 2011 - link

    Here's a general suggestion for hardware reviews: could you plug the gizmo under examination into a power meter instead of just the wall and eyeball up some numbers? These days green geeks fret over these matters, especially for 365x24 devices like routers. The badge or spec. numbers are often worthless. Just a thought, thanks.

    Oh, nice review, BTW. I agree that the recent Apple 802.11 gear is getting boringly reliable and decent, in a good sense. You can't tweak the firewall in quite the gruesome detail I'd like, but the box never needs attention or unplanned restarts. The he.com tunnel works fine, the BSD/Roku/Apple/Sony/Epson clients are happy, there is no drama to upset the non-geeks. Not bad, even for the price.
    Reply
  • Brian Klug - Saturday, August 6, 2011 - link

    I actually completely forgot to mention my Kill-A-Watt numbers. I don't recall the Time Capsule numbers off the top of my head, I saw a peak power use of 11 watts on the Airport Extreme Gen 4 (while data was being transacted on 2.4 and 5 GHz) and 12 watts on the Gen 5.

    -Brian
    Reply
  • ThomasA - Saturday, August 6, 2011 - link

    Yes, I read of MRT/Cacti. Also looked into replacing AE with a Netgear WNDR4000 that offers the data usage meter. I'd prefer the Apple, but must look ahead. Too bad. Reply

Log in

Don't have an account? Sign up now