Landmarks in public safety radios

rough draft

AM bases - 1920s

FM - ?

mobiles 1930s

backpack radios - ? 1935

repeaters - 1939 ?

lunch box size portables - ? 1945

1950s - paging systems

1955 ? - earliest interops channels 153.83 46.30 154.265 154.28
154.295 155.34 155.475

1960s - transistors brought multi channels and hand held portables and UHF

1980s - trunked systems and data terminals

1990s - cellphones

1995 ? - P25

2000 - ( ? faster paging systems ? ) & vtacs / utacs / itacs

2005 ? - cheaper satellite phones

2006 ? - GPS makes travel routing much much easier - ? but very few
public safety use it ?

2013 - narrowbanding of VHF & UHF provides 100% more channels

-- 
You received this message because you are subscribed to the Google Groups 
"massfire" group.
To unsubscribe from this group and stop receiving emails from it, send an email 
to massfire+unsubscr...@googlegroups.com.
To post to this group, send email to massfire@googlegroups.com.
Visit this group at https://groups.google.com/group/massfire.
For more options, visit https://groups.google.com/d/optout.

Reply via email to