EMC273 ALE Experiences 3/5
To:   Emergency Communications Units - Information Bulletin
To:   Emergency Management Agencies via Internet and Radio
By:   Auxiliary Communications Service (ACS) of the
      California Governor's Office of Emergency Services  

EMC273 ALE Experiences 3/5          Release 1/22/01

For any ALE system to work there must be a specific address for
each radio, much like a telephone must have a specific number.
For the Motorola units OES planned for 110 ALE addresses. That,
and other system requirements, meant that Motorola had to modify
the PROGRAMING software at its facilities in Israel.

The OES Motorola HF radio ALE network was originally intended as
a backup to the OASIS satellite (telephone) system. The original
concept called for a satellite and HF radio in each Operational
Area (counties, etc.) of the state along with other agencies for
a total of over 100 radios. Initial legislative funding was for
26 radios at OES with an additional 15 at 2 other state agencies.
In later years, funding for further radios did not occur due to
budget constraints and other factors. The final installed system
called for 41 radios at 40 locations with one standby. However,
over time, unit failure resulted in fewer active radios.

Prior to the completion of the ALE system we used the 10 channel
STACOM system on a Motorola MICOM radio (non-ALE) as our primary
in-house emergency radio linkage. It provided links between the
State OES facilities, although there were others (such as NASA
and USGS) on the system. We monitored one key channel in the
NON-ALE mode on STACOM and continued to use that until the XF ALE
system was implemented.

STACOM is the title California OES gave to a system known as
SECURE (State Emergency Capability Using Radio Effectively.)  It
covers 2-8 MHz HF-SSB radio frequencies allocated only to State
CD/ES agencies and provides OES with 10 channels. The acronym
"STACOM" was used to avoid the connotation of secure (encrypted)
communications.

When the Motorola radio ALE network was first setup the master
radio in Sacramento sounded 10 channels to each radio on the
network. Later we reduced sounding to 5 of 10 channels as others
were so close in frequency it was not necessary. In addition, the
sounding was reduced to a select group of radios in concentric
circle locations (from Sacramento) in order to reduce the number
of soundings. Those locations were placed 150-200 miles from the
state capitol where the distance to each end of the state is 500
miles in a north and south direction. These changes reduced channel
interferance from the ALE bursts when sounding: ...a raspy whirling
burrrrrrr...that covers voice communications when in use at the
same time by a non-ALE user.
  
The STACOM channel we were using for non-ALE monitoring, while
assigned to CA, was also in use by others for ALE sounding. We
were unable to identify from where or by whom those bursts
originated without having a compatible unit to the other system.
Then, at times there were South or Central American voices as
well as an overseas broadcast station that broke through the
squelch. That, and our own ALE sounding bursts, made single
channel monitoring not feasible because the loud ALE bursts
overrode the squelch. While operators in a CommCenter could put
up with that, executives and warning controllers would not.
(The lack of noise at the console is a MAJOR benefit of a
properly designed and installed ALE system. When the unit rings
you answer the phone. Otherwise, no noise, no tuning, no bursts,
no broken squelch, just restful quiet.).
Continues next bulletin.

 Cary Mangum, W6WWW        E-mail: cary.mangum@macnexus.org
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EOM