Repairing a Time Capsule

25 July 2015, 09:43


I’ve decided to entirely rewrite this posting bearing in mind the new information I’ve discovered, and to discuss things I’ve been attempting in order to make everything work sweetly.

First, a preamble. Apple’s Time Machine backup system is a work of genius. Just attach a USB/Firewire/Thunderbolt drive to your Mac and it’ll quite literally take care of the rest. It backs up the entire disk — the system and your data, all in the same scope.

Even better is a Time Capsule. This is hardware from Apple that puts a hard disk inside a AirPort Wi-Fi base station, so that you can use Time Machine across Wi-Fi or an Ethernet connection. You can just put the Time Capsule in the corner and leave it to run.

The trouble is cost. Time Capsules are humorously expensive considering what they are: £249 for the cheapest 2TB model, for example, and a hundred quid more for 3TB. I mean, I can afford that, but I’d spend the rest of my life failing to comprehend how I could spend that much money on a basic hard disk coupled to a Wi-Fi base station. Total manufacturing cost to Apple really can’t be more than £40.

So I just managed to fix up a broken Time Capsule and create my own 2TB model. This isn’t unusual, although I thought I’d add my own story to the roster.

Doing so has been quite an adventure. The Time Capsule I got was an original model that were known for dying within 12-18 months because of heat death. Put simply, these early devices were badly designed and, if that weren’t enough, also suffered from a poor choice of components.

The PSU works hard, so gets very hot, and the standard 3.5in desktop disk Apple used gets hot too. On the bottom of the Time Capsule is a silicone mat that’s glued in place and is there primarily designed to protect users from a metal plate, which could become electrically live if there’s a fault. The mat is a very good insulator and that doesn’t help the heat issue.

The Time Capsule I got was £12 from an eBay seller. It was listed as having “no PSU”. The number one cause of death of Time Capsules is that the PSU (power supply unit) dies because its capacitors overheat and “pop”.

I took a punt and it turns out that the seller meant that there was no power supply cable. The PSU was still inside and, unlike I had assumed, the seller hadn’t attempted any kind of repair. It had just died, and he’d stopped using it. In fact the unit had never been opened-up. The missing cable is a standard figure-8, used pretty much everywhere in the world.

From a cursory inspection of the hard disk contents (the previous owner didn’t encrypt his backups – doh!), it appeared this Time Capsule actually lasted around 3-4 years before death, which is very good going for these models. Maybe this was because of the climate here in the UK being cooler than, say, Florida or Australia.

To cut a long story short, I was able to source a replacement power supply for £28 via eBay (around $60). This was a reconditioned model and I assume somebody takes knackered Time Capsule PSUs and replaces the capacitors — a pretty easy job if you’re anywhere good with a soldering iron. Sadly, I’m not.

Swapping out the PSU and drive for different models is easy if you’ve ever been inside a PC. The Time Capsule is modular, and there are really only three major components: the PSU, the drive (standard SATA), and the mainboard. All connect to each other by cables that are easy to disconnect.

Initially I fitted a 2TB Western Digital enterprise-class desktop drive to the Time Capsule. After a quick format via the AirPort Utility on my Mac, this worked just fine but the Time Capsule case became really, really hot. Not just warm. Hot.

I tried removing the silicone panel beneath and fitting rubber stud feet, as you find on most other electrical devices, and this helped a little but the metal plate on the bottom was still too hot to touch. The top of the unit, where the Apple logo is, was in places too hot to touch for more than around 5-10 seconds.

To be honest this setup might’ve worked for years but all that heat just didn’t seem very sensible. As a result I splashed out on a 2GB laptop drive, another Western Digital model but this time a “Green” model designed to use less energy than even a typical laptop drive’s already low requirements. I already tested the Time Capsule with an old laptop drive I had lying around, and it works fine, although the drive can’t be fixed in place. However, it’s not as if I’m going to be throwing the Time Capsule around.

The PSU still gets hot but the laptop drive’s contribution to this heat seems negligible. There’s still a spot on the metal underside that’s too hot too touch for more than a few seconds, but the top is now merely warm and even cool in parts.

I believe some people don’t consider what I’ve done to be any kind of decent solution because the PSU still has to work hard to power the drive, even if it now only supplies 5V rather than the 12V required for a desktop drive. However, I understand the PSU fails because of heat build-up inside the case, and anything that can be done to decrease the heat — such as fitting a low-power laptop drive and removing the mat from the bottom — can only be sensible. Indeed, before Apple redesigned the Time Capsule into its current “tower” shape, this is how they overcame the design issues — they switched to using “Green” desktop drives that are slower than regular drives but also pump out less heat.

The total bill for my reconditioned Time Capsule is STILL less than that of a new Time Capsule, but splashing out on the extra 2GB laptop drive was more expense than I wanted. On the other hand, what price good backup? And I get to plug my printer into the Time Capsule too, overcoming a driver bug that meant the printer would stall after a single print job had been sent to it. And the Time Capsule is a 802.11n wi-fi base station, too, and my Mac connects at the near-maximum 150Mbits — fast enough for the 60-70Mbit DSL connection in my home. So it all makes sense!

EDIT: Regarding the last paragraph about network speeds, I notice that the box the Time Capsule came in promises only 2.5GHz frequencies, but the official spec list and also AirPort Utility mention 5GHz. I switched it on and, sure enough, with the absence of interference I now get 300Mbits over Wi-Fi with 802.11n.



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