NERA Repeater
System History
NERA began over 20 years ago when several engineers employed at the CBS
Television Network and the FCC built the WA3KOK repeater system in
Washington DC. The original system was designed to provide hand-held
coverage throughout the greater DC area. This was one of the first 440 MHz
repeaters using multiple remote receivers to provide this type of coverage
in the area. Corporate sponsors have been wonderful benefactors throughout
our history. NERA has received generous support from several state and
corporate sources including Team Video International, CBS Television, and
the National Weather Service to mention a few.
1993
Surprised that the practice of extensive linked repeaters so prevalent
in the Western United States didn't really exist in most of the East,
several members of NERA began an expansion effort. The K3HOT repeater in
Germantown, Maryland was linked full time to the Washington WA3KOK repeater.
This expanded the coverage of the NERA system to Washington's western
suburbs.
1994
In 1994 a new WA3KOK linked repeater was installed on Cacapon Mountain located in Virginia near Berkeley
Springs, West Virginia. This addition extended system coverage to include
most of Central and Western Maryland, the eastern panhandle of West
Virginia, northwestern Virginia, and southern Pennsylvania.
1997
In 1997 the K3HOT linked repeater was installed at 4030 feet AMSL atop
Fork Mountain in the Blue Ridge Mountains, Madison County, Virginia. This addition increased coverage to include
fifty-seven counties in central Virginia and eastern West Virginia. The
NERA system now covered an area extending from Washington DC to West
Virginia and from the Pennsylvania border to Charlottesville Virginia.
2000
After several years of planning the installation of another WA3KOK
linked repeater at Bull Run Mountain in Prince William County Virginia was
completed. This new repeater provided additional coverage up and down the
Interstate 66 corridor. Additionally, the relatively central location of
this machine provides backup coverage into areas already served by the
other machines.
2001
During the year 2001 we made a trip to Fork Mountain to replace the link
antenna with a brand new Comtelco 5 element beam.
The Comtelco beam is very rugged and should be
capable of withstanding the severe winter weather at the site better than
the previous two antennae that were used at the site, we hope. In December
the NERA system was expanded to High Knob Mountain near Linden Virginia
through the addition of the N1TXI machine. This machine is sponsored and
maintained by K4QJZ and N1TXI and will fill in nicely up and down the I-81
corridor. There are also plans in the offing to have this machine provide
cross-band repeat operation in early 2002.
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Through
the efforts of VE7LTD and his Internet Radio Linking Project the linked
NERA system now provides worldwide telecommunications via amateur radio
through an Internet interface. The system currently covers most Canadian
provinces, Hawaii, Alaska, Great Britain, Germany, Australia, The
Caribbean and many states throughout the contiguous United States with
new nodes coming on-line almost daily. If you've not used the IRLP
before, please refer to KWARC's IRLP Page for valuable guidance.
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2012
Late in 2012 NERA added a digital P25 input mode to its main 449.975
repeater. The receiver is located in NW DC on a tower with the antenna at
450 feet. The input is on 444.975 wideband with an NAC of 293. The received
P25 signal is transmitted via FM link to the main site where it is
retransmitted FM on 449.975. (Note that you must set your radio to mixed
mode receive if you are transmitting P25 and listening to the main site,)
Experience shows that the received coverage of this new site is somewhat
better in the DC metro area than the regular FM input. The clarity and
crispness of the digital signal is quite apparent to the user. Please note
that use of the NERA system is restricted to members only, except for
transients, and also for public service events that have been arranged in
advance.
Also late in 2012 NERA rebuilt, reactivated, and expanded the site of
its currently non-linked VHF repeater in Germantown, Maryland. Located just
off Interstate 270, this repeater’s antennas are at 390 feet and provide
excellent coverage of Montgomery and Frederick counties, as well as some
coverage into Northwest DC. Best of all, this repeater consists of two
separate systems, one being analog FM and the other P25 digital. Both
systems at this site are wideband. What you input to this repeater is what
is transmitted, but it can only handle one mode or the other at a time. The
FM analog input has a PL of 156.7, and the P25 requires an NAC of 293.
Input frequency for both systems is 147.870 and the output, again for both
systems, is 147.270. Our plan is that this repeater will eventually be
linked to the NERA UHF system but at this time (January 2013) it is a
standalone repeater. Please also note that, at
this time, this repeater is open for all to use.
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