Accessing external DVRs' HDD & formatting for a larger drive

[videobruce]

This is probably going to be a tough one since it is involving unchartered territory.
There are 3rd party external HDTV recording devices that will work with certain HD TV's that have the HAVi interface and 1394 ports. The use a HDD to record NTSC/ATSC (OverTheAir) & QAM (Cable) material.

This is one device that has promise;
http://www.indigita.com/products/customsolutions/avhd.html

Problem is; price and size of HDD. What I want to know is how would one replace the included HDD with a larger one.

I received a e-mail from Indigita and the relevent portion is as follows;

The AVHD drives are specially formatted to maintain the 5C content protection and are not user installable or replaceable........The AVHD is designed specifically for today's new Digital Cable Ready HDTV's.......the AVHD incorporates 5C encryption and is able to record authorized copy protected programming from DCR TV's.

What I'm concerned about is the "specially formatted" and the "5c content protection" parts.

Someone else has one of these (a 40GB dealer demo unit) and tried to access the HDD via a USB port. The O/S saw the device but couldn't read it or even show a drive letter. I am going to ask him to put it on a IDE bus and see if that does anything.

How can one figure out exactly what type of "formatting" this uses?

 

[Mark R]

As I understand it "5C encryption" is a technique for protecting pay-per-view and subscription channels which are broadcast over cable and some over-the-air channels. Without an appropriate card which contains the encryption key, you won't be able to watch the programme.

5C can also be used to protect firewire connections. It looks like this AVHD box requires 5C firewire. This means it will only communicate with other 5C firewire devices, and more importantly, only with authorised 5C firewire devices.

Many DVRs now contain specially modified hard drives which are optimised for streaming media, extremely low noise and low heat - basically slowed down versions of the drives you get in PCs with special optimised firmware. (the buffer is designed for streaming, and there is different handling of bad sectors).

If you want to take the drive out and put in in a PC then there are 2 problems:

1) a number of DVRs use a proprietary format on the HD (i.e. not FAT, NTFS, or any regular format). You could try to reverse engineer the format if you are really interested and technically minded - but that's about the only way you'll get any info about it. The manufacturer's don't want people modifying their boxes, and the content providers don't want people copying raw off-air data onto their PCs. So, don't count on anything useful from the people that do know about it.

2)it's common for DVRs to just stream the data directly off air onto the HD when recording. This means that the data recorded on the HD is exactly what came off air - in other words, it's still encrypted. When you play the recording, the encrypted data is decrypted there and then. (This allows pay-per-view programmes to remain pay-per-view, but gives you the flexibility to watch at a later time).

Changing the HD is a slightly different problem:

It should be much the same as existing DVRs: Open up, Remove the HD and insert a new one. Power on, and perform a 'factory reset'. The factory reset will usually format the drive and get everything set up.

Whether you get the extra capacity, or whether there are any weird bugs, who knows. Some older DVRs didn't work properly with big drives because the software was designed to expect a specfic drive capacity. Conceivably, the software may refuse to operate if it doesn't detect the original drive.

There are a couple of other catches - DVRs are very poorly ventilated and the electronics get hot. A 7200 rpm drive may simply overheat (but good luck finding a 5400 rpm drive of the desired capacity).

On some the HD mountings have integrated heatsinks that are supposed to make contact with the chips on the drive - a different model of drive may not fit, and you may need to cut the heatsinks off the mounting.

 

[bobsmith1492]

Originally posted by: videobruce
This is probably going to be a tough one since it is involving unchartered territory.

Would that be "uncharted" territory, or territory that has not been rented out yet?

 

[videobruce]

Would that be "uncharted" territory, or territory that has not been rented out yet?

Ok I spelled it wrong...............

Mark R; There are 5400 RPM drives out there made for DVRs'. Maxtors' QuickView for starters. You are correct on the heat issue. LG has a LST-3410a that another HDD can be subbed with few problems, but that is a stand along unit with a built in tuner.

 

[Mark R]

There are 5400 RPM drives out there made for DVRs'. Maxtors' QuickView for starters

That is true. However, these drives are not supplied to retailers or distributers. They are sold directly to OEMs only. Very occasionally, grey market QuickView drives appear for sale on places like eBay, or some bargain basement shops.

 

[videobruce]

I have done searches and found more than one on-line retailer selling these drives.