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First in a series of shirtsleeve drive reviews
Ecrix's VXA drive is an interesting entry on the market. The manufacturers claim that the drive has a native transfer rate of 3MB/sec. The V17 tape promises a native capacity of 33GB. With compression, these numbers can be expected to be about double the native numbers.
Although the drive is, at its heart, an 8mm helical scan tape drive, using technologies similar to Exabyte's 8mm drives and Sony's AIT drives, it also has many differences. Perhaps the most prominent is its sub $900 street price-the nearest 8mm competitor on price (and not capacity) alone is Exabyte's Mammoth LT with a street price of about $1,250 (a full 1/3 higher). By contrast, the Mammoth LT writes to tape with a 14GB native capacity and has a transfer rate of 2MB/sec. On price alone, the VXA-1 looks like a bargain when compared to its 8mm cousins.
Other than the fact that all 8mm drives use cartridges that appear to be roughly the same size and all have a rotating 8nun drum and a somewhat similar tape path, many of the similarities end there. The VXA-1 has four heads, all working simultaneously, implementing what Ecrix calls Discrete Packet Format (DPF). Data is written to the tape in small packets. Each packet features error correction code. Each packet is individually and uniquely numbered. The packets are assembled into a two dimensional matrix-error correction code can rebuild lost packets based on vertical, horizontal, or diagonal error correction data. The result is purported to be extremely error tolerant and highly accurate. Specially developed ASIC accomplish the near miracle of packet writing and packet reassembly.
Additionally, Ecrix drives include what is referred to as Overscan-each packet passes at least two heads. If one head doesn't correctly read the packet, a second one gets another crack at it. Further, motor speed control allows the drive to adjust to the speed that the computer can support-if a data stream from the computer slows down or speeds up, the VXA can accommodate to the change by changing the speed of its motor. Similarly, if data going from the drive to the computer drops in speed (for example, when the computer's data buffer is full and it...