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Information on the REPEATER SYSTEM
I own and operate a HAM (Amateur Radio)
repeater system in South-central Dakota County, which is about 30 miles SSE of the Minneapolis-St. Paul, Minnesota area. The repeater is near Hampton, which is 30 miles South-East of
the MSP metro area on highway 52; It can be heard on 147.360 Mhz, if
you have a scanner, or a 2-meter FM radio.
This repeater has two independent, but PARALLEL COR (carrier operated squelch) circuits on board. As a result, one can access this repeater with a valid signal on the input of the repeater, no matter if the sub-audible tone of 136.5 Hz is present or not on a user's transmitter.
I have a spare (redundant) repeater, complete with all of the needed controllers, duplexer, antenna, etc. on hand. The alternate is sometimes pressed into service, if the one in service develops a small problem.
To use the repeater, set your transmitter to 147.360 Mhz, POSITIVE offset. If you would like the maximum range, set the transmitter to send 136.5 Hz, which will allow the repeater to have a LOT better receiver sensitivity.
It is an "open" repeater system for the active
radio amateurs in this area, or for licensed hams who are simply
traveling through this locale.
Here's a picture of the PRESENT antenna system for the repeater. I am presently employing two of the DB-224 antennas, using an ANTENNA SPECIALIST'S power divider to join the two. As you can see, I also have a redundant antenna for the repeater. (See the picture below.)

Echolink
This repeater system is equipped with EchoLink. Read about Echolink here!
My repeater (on 147.360 Mhz output) has the Echolink node number
9636. The Echolink "node" number of 9636 was chosen as my
"repeater pair" is 96-36. (147.96-36 Mhz.)
Sample questions:
Is Echolink available for any platform other than Windows??
Echolink is designed specifically to run under Microsoft
Windows. Currently, there are no plans to offer versions of EchoLink for
other platforms.
However, if you are running a Macintosh with OS X, you can use the
program EchoMac by
N9YTY, which is compatible with Echolink. If you do, please first
register here
to begin the validation process. (Support for EchoMac is not available
through the Echolink Web site.)
What's the easiest way to test and adjust my
audio?
There is a special "echo" conference server, called "ECHOTEST," to
which you can connect to test your audio. Once connected, the server
simply records anything you transmit and plays it back. This is a
convenient way to verify that your transmitted audio is clean, and to adjust
record and playback sound levels. You can connect by choosing "Connect to
Test Server" from the Station menu. If you are connecting to EchoLink via
an RF link, the node number for "ECHOTEST" is 9999.
Here is
some basic information on my system...
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Command
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Description
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DTMF Code
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Connect
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Connects to a station on the internet, based
on its node number. The node numbers can be 4, 5 or 6 digits.
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nnnnnn
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Random Node
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Selects an available node (of any type) at
random, tries to connect to it.
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00
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Random Link
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Selects an available link or repeater (-L or
-R) at random and tries to connect to it.
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01
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Random Conf
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Selects a conference server at random and
tried to connect to it..
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02
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Random User
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Selects an available single-user station at
random and tries to connect to it. .
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03
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Status
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Announces the callsign of each station
currently connected.
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08
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Reconnect
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Reconnects to the station that was most
recently disconnected.
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09
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Disconnect
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Disconnects the station that is currently
connected. If more than one station is connected, disconnects only the
most-recently-connected station.
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#
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Play Information
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Plays a brief ID message.
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*
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To
establish a Echolink connection with your radio
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- It is recommended that you first identify
your station on the repeater and that you are attempting Echolink
operation.
- Optionally, you can determine if the Echolink
gateway is operational by keying a "*" DTMF tone. The gateway node will
respond with status information.
- Type in the four, five or six digit station code
for
the station or repeater that you wish to link to.
- There is a special "echo" conference server, called "ECHOTEST," to
which you can connect to test your audio and verify that your computer and its PORTS are properly set. Once connected, the "ECHOTEST" server
simply records anything you transmit and plays it back when you stop transmitting. This is a
convenient way to verify that your transmitted audio is clean, and to adjust
record and playback sound levels. (Always use this as an absolutely positive way to test your system's settings!)
You can connect by choosing "Connect to
Test Server" from the Station menu on your computer. You do NOT need to be connected to a node to run this audio test; In fact, if you are connected to any node, these will be disconnected if you connect to node number 9999.
If you are connecting to EchoLink via
an RF link, the node number for "ECHOTEST" is 9999. (Transmit "9999" when you are connected to any Echolink access point or node.)
(Summary: -You can TEST
your system by connecting to the "Test Server" at node number 9999.
-Enter "9999" on your radio's touch-tone pad, then follow the
audio
response information. When the test server stops talking, TRANSMIT to the test
server, then LISTEN to how you sound. Test as much as you need. Be sure to disconnect from the test
server when you are
finished.)
- To continue with the normal use of the Echolink system: After you have transmitted the 4, 5 or 6 DTMF link number, there will be a few seconds delay, the Echolink node
will respond with a "Connected" message if the link was successful. If
the link was not successful, key a "#" to disconnect the gateway node.
- Following a successful connection, announce
your presence on the linked repeater by calling a short CQ, or by announcing your
intentions in some other way of your choice.
- When you are in QSO on Echolink, there IS NO NEED to delay your response to the other party. You are clear to transmit as soon as you hear the repeater's courtesy beep. (Delaying will only slow down your conversation...) At the end of the QSO, disconnect the link by
keying a "#" DTMF tone. The Echolink gateway will respond with
confirmation that the link has been disconnected.
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Accessing
Echolink From Your Computer
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Perform
the following the access a Echolink station or repeater from your
computer.
- Download and install the iLink user program
from the Echolink web site.
Macintosh users can run EchoMac, which is described on the
Echolink web site above. EchoMac is available at http://www.dogparksoftware.com/EchoMac.html
- Verify that you have a microphone properly
connected to your computer and the the microphone input volume level is
properly adjusted. (See step 4 below.)
- Connect to the internet and run the Echolink
or EchoMac user program.
- TEST your system by connecting to the "Test
Server" at node number 9999. (Enter "9999" in the "connect to"
window, then follow the audio response information. When it is
your turn, TRANSMIT to the test server, then LISTEN to how you sound.
Disconnect from the test server when you are finished.)
- After you have adjusted your system, you may
select a station or repeater to link to, from the displayed Echolink
station link. (Double-click the station on the list to connect, as an example.)
When you are in QSO on Echolink, there IS NO NEED to delay your response to the other party. You are clear to transmit as soon as you hear the repeater's courtesy beep. (Delaying will only slow down your conversation...) At the end of the QSO, disconnect the link by
Selecting DISCONNECT from the program's menu. The Echolink gateway will respond with
confirmation that the link has been disconnected.
- Once connected, use the Enter key or spacebar
to toggle between transmit and receive.

Rural Minnesota! We grow REPEATERS, as well as corn...
(Click on the small image above to see the full size picture...)
The K0JTA tower was originally 140 feet tall.
It was a self-supporting tower, manufactured by Rohn. It suffered storm damage, and is now just 40 feet tall. The tower's concrete footings are 11 feet
deep. This tower (and secured structure) is the "home" of the
147.360 Mhz repeater system described below. [-For more info and pictures on both of these events, see the "damage pictures" link.]
The repeater system has a range of more
than 30 miles, depending on the terrain, and the configuration of the
mobile radio. (Some mobiles have somewhat better range.)
The transmitter (TX) and receiver (RX)
that make up the repeater are made by GE. (Mastr IIe
series.) The repeater has a 75 watt transmitter. I have the
transmitter set to produce about 25 watts of RF power out of the
duplexer at this time. The repeater receiver has a GE Mastr II
"preamp" to assist the reception.
In the summer of 2002, the repeater
system was severely "kicked" by power-line sourced lightning
damage. As a result, I had to get a different radio (A Mastr IIe)
and controller, and develop a new repeater system. (I also had
to add a new power supply, as the original was toasted...)
I made up a second repeater, as I like
the redundancy this can offer.
The MAIN duplexer is a Sinclair 4-cavity unit. The SPARE duplexer is made by Wacom, and is a full-size
duplexer.)

Above: The GE Mastr IIe,
with NHRC controller and digital audio delay. To the right of the GE radio is the Sinclair duplexer. Above the duplexer is a dual RF power and SWR bridge unit. With this, I can monitor the repeater's RF power INTO the duplexer and also OUT of the duplexer. I can also check for any reflected power, etc.

Above: The
location of the spare duplexer, which is made by Wacom. The "lightning box" is a home-made version of what is commercially available. It is made of stainless steel, and has the needed lightning arrestors and large (redundant) grounds. The "MAIN antenna feed-line" is just under 2 inches in diameter. The hard-lines to the main and the backup repeater antennas have a 50 foot run.
(Click on any of the small images above to see the full size
picture, then use your BACK BUTTON to return to this page...)

The MAIN repeater antenna system is a DB Products
DB-224E. It is top-mounted on the tower, at the 40 foot
level. The antenna is about 24 feet long. This antenna was
put into service in September, 2003. New "almost 2 inch" Heliax was
installed for this antenna. This feedline is extraordinarily
large! (The connectors
cost me $125.00 each!) -Way
too big!
The STANDBY antenna system is a Hustler 7
dB unit. It is side-mounted on the tower, at about the 40 foot
level. This antenna was put into service in 2001. The
MAIN repeater antenna is presently being fed with two inch hard line. This feedline for the spare repeater antenna is half-inch Heliax.
Below: Views from the
crane, when the new DB-224E was installed at the top of the THEN 140 foot self-supporting Rohn tower. (from the TOP!) This tower was damaged, and is now only 40 feet tall.
Tower damage to 140 foot tower:
The top 100 feet on the self-supporting 140 foot tower was blown down on the evening of September 16, 2006! [-For more info and pictures on both of these events, see the "damage pictures" link.]

Above: Looking down the
boom.......

Above: The garden (and
the crane, at the lower-right...)

Above: A second view of
the business end of the crane.
Below: More views from
the top..!

Above: The shadows.......

Above: Looking DOWN at the top of a 140
foot self-supporting tower!
(We are
about 15 feet above the tower at this time; -Resting, as we wait for
the ground crew to secure the new antenna, and hoist it up to us.
The old UHF antenna is at the left on the ground, and the new DB
Products antenna is at the right.

Above: My helper in the
bucket is Mark, K0MDM

Above: Looking down on my THEN
puny little 56 foot Rohn tower, at the left. -Turns out, this one is now the "big tower!"...
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