While the build quality of QIC/Travan cartridges is superb – making them ideal for long-term storage – for a long time they are more expensive than DAT media. This was especially so for the 8GB/Travan-4 cartridges, which have built-in tape alignment and tensioning, thereby reducing the amount of hardware needed in the drive itself.
By the end of 1998, a TR-5 format was available – offering a capacity of 10GB/20GB and minimum DTR of 1MBps. Storage capacity over the TR-4 format being improved by increasing the number of tracks from 72 to 108.
Somewhat confusingly Imation – the effective custodian of the Travan standard – has used an alternative naming convention since the introduction of its Travan NS (network series) format in 1997. The first Travan NS, the NS8, was equivalent to the TR-4 format. The TR-5 equivalent, the NS20, is servo written and preformatted to the QIC-3220 standard. The servo information cannot be replaced on the cartridge, making it impossible to reformat. Bulk erasing (degaussing) renders the cartridge unusable.
The following table shows the principal characteristics of the various Travan formats to date:
| TR-1 | TR-2 | TR-3 | TR-4 | TR-5 | |
|---|---|---|---|---|---|
| Capacity:
Native Compressed |
400MB
800MB |
800MB
1.6GB |
1.6GB 3.2GB |
4GB
8GB |
10GB
20GB |
| DTR:
Minimum Maximum |
62.5 KBps
125 KBps |
62.5 KBps
125 KBps |
125 KBps
250 KBps |
60 MB/min
70 MB/min |
60 MB/min
110 MB/min |
| Tracks | 36 | 50 | 50 | 72 | 108 |
| Data
Density |
14,700
ftpi |
22,125
ftpi |
44,250
ftpi |
50,800
ftpi |
50,800
ftpi |
| Compatibility | QIC 80
(R/W) QIC 40 (R only) |
QIC 3010
(R/W) QIC 80 (R only) |
QIC 3010/
QIC 3020 (R/W) QIC 80 (R only) |
QIC 3080/
QIC 3095 (R/W) QIC 3020 (R only) |
QIC 3220
(R/W) TR-4 QIC 3095 (R only) |
A TR-6 format is slated for availability in early 2001. This is expected to incorporate the VR2 (variable rate randomiser) technology developed by Overland Data. Essentially, VR2 will be used to incorporate PRML channel encoding, as used in hard disk technology, into linear tape drives. It is expected to give a 1.5 to two-fold increase in capacity and performance without requiring changes to the tape path design, recording heads or media.