The coverage (ability to receive a page) of pagers varies from location to location. See California Coverage for coverage by our current vendor (Verizon) in California. Even within areas in California that are supposedly covered, some locations have poor or no reception. The coverage on-site at SLAC is poor in several areas. There have been complaints from several areas at SLAC including:

• Building 5:
  • Conference room
  • Main control room
  • Video head end
  • Kitchen
• Collider hall
• Building 120 SSRL
• The CID (injector area)
• Computer center video conference room

These areas typically can't receive a signal at all or the signal is so weak that pagers work only intermittently. To rectify this a study is needed to identify and prioritize areas where it is critical to be able to receive pages, to measure the losses in those areas, to evaluate possible solutions and put forward a plan. This is a major project which so far has not planned assigned, funded, or initiated. We are in the process of interviewing other vendors and undertaking a pilot program for new service.

The PEP tunnels have a special antenna system, maintained by the Controls Department, for coverage using special (152MHz Verizon) pagers. It has not been extended to the Interaction Region control rooms (in particular IR2). The accelerator tunnel, SLD and SLC have an old antenna system, maintained by the Controls Department, that works with the special (150MHz) pagers, but is not 100% reliable.

SCCS Network operations have been working with the NLCTA folks to look at some possibilities for the NLCTA, but no installation of antennas, repeaters or anything has yet been funded. The contact person on this is Fred Hooker.

Telecommunications is looking at a possible solution from Ericsson that may allow cellular phones to be able to work on more areas at SLAC. The contact person for this is Brenda Eberle.

We are also looking at other ways to try and help in particular the use of 2-way pagers. These communicate with the nearest transmitter on a regular basis, so the transmitters knows whether the pager is reachable. If the pager is reachable the page is sent. Since the pager can also communicate, the pager user can also send a message back (it has a small keyboard). The pager automatically responds it has received the page to the pager service provider assuming it can be heard by the remote receivers, otherwise it responds when it gets back in receiver range. By means of the keyboard the pager user can also respond to a page by email. If the pager is out of reach of a transmitter then the page is stored and sent when the pager comes in range again. These pagers are slightly bigger (10% larger for the T900 series, and roughly 50% larger for the Pagewriter 2000 series, in comparison to the standard Motorola Advisor pagers). We are testing a couple at SLAC. They are available with the existing Verizon contract for support personnel only as test pagers. The contact person for this is Les Cottrell.