Our main reference servers, tick is right and tock is left. On the left side are the two radio clock receivers. The left one is the Expert mouseCLOCK connected to tick, the right one is the IGEL:clock connected to tock without the adapter.

The PCs share keyboard and monochrome monitor by the switch box below the monitor. tick is an i486 25 MHz, tock an i486 33 MHz. Both have 8 MB RAM, ISA bus, IDE adapter, 200 MB disk, NE2000 compatible NIC and a color graphics card. There is only a floppy disk drive and no CD-ROM drive.

Both boxes are running S.u.S.E. Linux 5.2 with kernel 2.0.33 without graphical user interface. RAM and disk space are fairly sufficient for that. But for Linux installation we had to mount the disks into tack (below) having 16 MB RAM and a CD-ROM drive. Thereafter the disks were mounted into tick and tock and additional software installed from the network.

The NTP daemon is still version 3 (xntp3-5.93-export), and we will not change that because the quality of service is so good. Linux will stay unchanged too for obvious reasons.

This is my own old PC bought 1992 and upgraded later: i486 50 MHz, 16 MB RAM, ISA bus, EIDE controller and 1.2 GB disk (1996), double speed CD-ROM drive, NE2000 compatible NIC, 1 MB color graphics card, 14" color monitor. It was too weak for MS Office 97.

It's now running S.u.S.E. Linux 6.3 with kernel 2.2.13 and optional graphical user interface (slow). NTP daemon is the preinstalled version 4 ntpd.