09 March, 2015

Repairing a tape backup LTO 2 unit: HP Ultrium 448 with broken tape

In a unit Ultrium Fujitsu (HP) for backup, the tape had broken, being useless as the mechanism for capturing the tape was inside it. To repair the unit is complicated, recommended only to those who have already dealt above with similar mechanisms (VHS, glory times). 
To repair it is necessary to understand the method these units use (and many other models are based on the same principle), a curious way to save space by having a single drum in the cartridge and in the unit, where the tape passes from one side to another as information is stored, until it ends.
These LTO (Linear Tape Open) are optimized for capacity, and the latest versions, able to store 2.5TB of information in one cartridge that costs about 20 €, making it very competitive in terms of price and space currently.
After this brief introduction, let's go to the subject.

To access the mechanics we have to remove the front (two side tabs) and remove a couple of screws on the top cover to remove it. Below is the principal control board, connected with three electronic bands that gently withdraw after lifting a thin lashes that fixed them, and remove. 
We lifted the lid of the way through which the end, releasing the two girdles, and screw on the side that secures the support of one of the strips, and looking to the following image, and the yellow connector cables, at last you can pry the tab on the right, and the piece goes up easily.

After that, the unit will look as shown in the following image, hang drum shaft the "cane" and capture the tape, which we will have to come his way up to the position of coupling.

You can see that I hold the coupling piece, that we must insert in the path
To carry the piece throught its place, the mechanical loader must be in position as if there was a cartridge loaded (if not, the cleaning piece doesn not let us insert the piece). To stop it I fastened the belt with a screw, and rotated the gears of the engine until it loads the invisible cartridge, until the clamping mechanism is put in place to capture the end, so the cleaning head hairs goes into its standby place.

The operation can be seen in the following video:

In the picture below, we see at the left near the axle, the cleaning piece already in place, and we can begin to pass the trailing end of the tape from left to right.

You can use a screwdriver to push the piece into its way to get into the shaft, to be in the following position, this piece is in charge of  "capturing" the end of the belt to carry the drum to the interior one, where the tape will go rolling.


And stay with the lid already in place, we put the tray insertion of the cartridge in place.

It is important to check that we have the top of the path correctly inserted, and that the head moves freely up and down (it calibrates the recording depending on the position of the tape), to do what got as seen in the image below:

And if when you drop it, falls under its own weight to the lower position, as you can see in the next image, it is well mounted. If brushed with something, the problem is that the end cap is not in place, or other problem.

 The capture mechanism tape cartridge

Assemble all again and check that it works well, no strange noises and charging while the tape is wound a bit and keeps the Ready LED on:

Well, I hope this tutorial had served to repair that damaged tape driver in the server, aboiding to buy another, and recycling electronics! Keep reading... soon!

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