Single signal

The choice of family follows the signal:

• Audio — the audio transceiver transmits analogue and digital stereo audio (SPDIF).
• Serial — the CAT-RS232-CPU/CON series transmits RS232. The U2+R range additionally covers RS422, together with USB.
• USB — the U2 ranges and the standalone USB extenders cover USB 2.0 through to USB 3.1 Gen 1.

The most important distinction within this category:

• Matrix-compatible are U2+R-CPU/CON (dedicated) and U2-LAN (KVM over IP). These modules can be integrated into a matrix system and switched there — the USB link then follows the workplace rather than fixed cabling. The split by transmission route applies here too: U2-LAN belongs to the IP world, U2+R to the dedicated one.
• Standalone are the audio transceiver, the CAT-RS232 series and the USB extenders. They connect two points permanently, independently of a KVM system.

With USB, three things decide: the version, the number of ports at the remote end and the transmission medium. USB 2.0 can run over CAT cable or fibre; for USB 3.0 and USB 3.1 Gen 1, the variants in the current portfolio use fibre. Models offer one, two or four ports — plan the workplace peripherals in advance, as the port count cannot be extended.

If you are using a KVM extender anyway, check its U or U2 variant first: it already carries transparent USB 2.0. A separate USB extender pays off where no video is involved, or where USB 3.x is required.

For RS232, the CAT-RS232 series is sufficient as a standalone pair. Where serial and USB are both needed — at operator desks or measurement stations, for instance — the U2+R range covers both in one module and additionally supports RS422.

The audio transceiver transmits stereo audio in both forms: analogue and digital via SPDIF. It works in both directions, which makes it suitable for intercom links as well as playback.

How far a single signal travels depends on the signal: CAT links cover short in-building distances, multimode fibre the campus, singlemode the long hauls. The specific reach is stated with each article — with USB it is considerably below what a KVM link achieves.

• My KVM extender already transmits USB. Do I need a USB extender as well?
  Usually not. The U and U2 variants of the KVM extenders carry transparent USB 2.0. A separate USB extender makes sense where no video is transmitted, or where USB 3.0 or 3.1 is required.
• Can USB 3.1 be transmitted over CAT cable?
  In the current portfolio, USB 3.0 and USB 3.1 Gen 1 run over fibre. CAT variants are available for USB 2.0.
• Can a USB link be switched in a matrix system?
  Yes, with the matrix-compatible ranges: U2-LAN in an IP matrix system, U2+R in a dedicated one. The standalone USB extenders connect two fixed points instead.
• Does the audio transceiver work in both directions?
  Yes. It operates as a transceiver, which makes it suitable for intercom links.
• How many USB devices can I connect?
  Depending on the model, at one, two or four ports. The port count is part of the variant and cannot be extended later.