NERA Repeater System
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
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.
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.
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.
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
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.
||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.
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.
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 repeaterís 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.