Good Grief! I appear to be mentioned in the question above; I am the Chris Fackrell referred to.
I can, and do, repair the TC PSUs that come my way. There are three basic types;
1. Flextronics Mk1
2. Flextronics Mk2
The DELTA units are very robust and can withstand the furnace temperatures far better than the Flextronics; they overheat and fail in a very predictable way, in that, the secondary capacitors cook and dry out. I remove all 4x of the main failure culprits and replace them with new superior parts, test the PSU on full load and reseal the plastic case holding the electronics.
I give a very easy-to-follow script for the repair of the Flextronics units, on my website listed above.
The DELTA PSUs almost never fail and by not failing they have revealed some very interesting facts about the TC design. (I'm in design, did I mention that?).
There is a basic, known, design flaw in the structural build of the Apple Time Capsule. It overheats - and high temperature kills electronics - FACT.
To obviate this heat problem, the Apple design team built in a very useful cooling fan and when connected and running it works very well. Unfortunately, the design with this fan has three basic faults...
1. The fan has no air inlet hole. It need cool outside air to displace the hot inside air.
2. It is pointing the wrong way. The 'hot spot' inside the TC is the PSU - it generates the power needed to drive the electronics and the hard drive but it is not 100% efficient (no PSU is). The surplus heat is not removed by passing cool air, so the PSU gets hotter and hotter.
3. The fan (as fitted) is not turned on. It WILL come on when a terminal temperature is reached by which time the TC is shutting down.
In Apple's defence, since this problem is known, they have at least on the latest versions turned the fan 'on' and made its speed proportional to an internal temperature sensor.
Too little, too late.
Please note, I will repair a PSU but only if you choose to remove it from the TC. Send me the WHOLE TC and I will repair the PSU AND modify it to run cool and remain so. I call this a 'F&M' (Fix and Modify).
I will NOT fix a PSU and put it back in a flawed TC, only to fail again.
Ahh... point not explained before, when I mentioned the DELTA supply... it highlighted that IT was not the weakest link in the critical chain of components that keep the TC running. The DELTA is tougher than the FLEXTRONICS. This toughness makes something else the weakest link within the TC, that will eventually succumb to excessive heat. That something, so far, has proved to be the main control board, which is beyond my present ability to repair.
Avoid these overheating problems and follow my website in the ways to do it...
Cut a hole. Flip the fan to point the correct way. Turn the fan on.
Sorry this answer was so long. It needed explaining... :-)
If the PSU is a Flextronics, probably yes.
If it is a Delta, I will decline; I have not seen the same fault twice, have no schematics for the PSU and hold no spares.
Address per the contacts page on my website.