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Florida Repeater CouncilWhat is the Difference Between a Repeater and an Auxiliary Station?By Gary Hendrickson W3DTN May 1997 This is a good question. Also, there is a lot of confusion about what
is a "remote-base"? Unfortunately, these questions have a very
complicated answer - I hope I can help. The simple, basic difference between a "repeater" and an "auxiliary"
station goes like this (by the way, for the purpose of this article, we'll
ignore any reference to the Rules for Amateur digital operation - that's
a whole 'nuther ballgame): A "repeater", at the very basic level, is an open station which
the F.C.C. Rules say is available for ANY other amateur licensee to use
(this basic concept ignores any usage limits or access codes which, according
the Rules, may be imposed by the repeater's sponsor). All receiving and
transmitting frequencies used by repeaters, including any secondary inputs,
must be within specific repeater sub-bands of the 29 MHz and higher bands
(refer to Section
97.205(b) of the Rules). "Auxiliary" operation, at the very basic level, is inherently
closed operation, which means that all auxiliary stations are part of a
"system" of stations. All operators of the system must be authorized
control operators. There are several forms of auxiliary operation, which
encompass a number of different types of activities, such as: 1. Remote control of a station, where a radio link is used. This means
sending some form of signals, such as DTMF tones, to another station to
change is operating parameters, turn it on or off, change frequencies or
power, rotate antennas, etc. These control signals are considered to be
a form of "primary" control of the station, or the control of
those parameters for which the station licensee and/or any other control
operators are primarily responsible. This does not include various "secondary"
control functions, such as those which may be used by "users"
of a repeater, i.e., to access an auto-patch, etc. 2. Voice links between two or more stations within a system of stations,
such as; a. Point-to-point links from a repeater's remote receiver(s) back to
the main repeater site (Here, the repeater and its associated remote receivers,
link transmitters and receivers, and any associated control stations, constitute
the "system". "Users" of the repeater are NOT part of
the system.); b. Dedicated point-to-point links between different repeaters in a "system"
of either full-time or part-time linked repeaters; c. Combination remote-control and voice point-to-point links intended
to control and carry the voice signals to the transmitter(s) of a remotely-controlled
station (this is the equivalent to replacing the wire between the microphone
and the transmitter with a radio link from the mike to the remotely located
transmitter). This form of auxiliary operation is commonly referred to as
an "up-link" (from the control point up to the remote station); d. Point-to-point links from the receiver(s) of a remotely located station
back to the control point (the equivalent of replacing the wire between
the receiver's audio output terminals and its loudspeaker with a radio link
from the receiver to a remotely located loudspeaker). This form of auxiliary
operation is commonly referred to as a "down-link" (from the remote
station down to the control point). ALL "auxiliary" operation must be on frequencies above 222
MHz (see Section
97.201(b)). Observe that repeater operation, and most of the auxiliary operations
described in Item #2, above, consist of a form of "automatic re-transmission"
by one Amateur station of the signals from another Amateur station. Although
no longer defined in the current version of the F.C.C. Rules, this term
used to be defined as any re-transmission of signals where the re-transission
occurs automatically with the appearance of a signal at the receiver, without
the transmitter's control operator having to take any direct action to key
the transmitter. The term is still used within the Rules. ONLY certain types
of Amateur stations are permitted to perform automatic re-transmission of
other Amateur station's signals - repeaters and auxiliary stations. So,
if your station is performing some sort of automatic re-transmission of
other Amateur stations, then your operations are subject to the Rules for
either repeater or auxiliary operation. From a practical standpoint, the electrical operation of repeaters and
auxiliary stations is virtually identical. The difference between the two
is how they are used. The term "remote-base"is not used anywhere in the F.C.C. Rules.
However, you will observe that if you combine items "2-c" and
"2-d", above, you can create the basics of a radio remotely controlled
base station - or, a "remote-base"! Also note that the Rules do
allow the "control point" for this "remote-base" to
be operated from a mobile control station. But remember that all of the
combinations of stations described in items "2-a" thru "2-d"
form closed "systems" of stations. Where a "repeater" is concerned, the "users" don't
need to send any sort of primary control signals in order to use the repeater,
and anyone can be a user. Users transmit and receive on the repeater's input
and output frequencies, which must be in appropriate repeater segments of
the 29 MHz and higher frequency bands. Whereas the repeater's users are
NOT a part of its "system", the "control operator(s)"
for a radio remotely controlled repeater ARE part of the system, and must
conduct all of their primary control functions for the repeater by a form
of "auxiliary" operation on authorized frequencies above 222 MHz,
as described in item "1", above. Where a "remote-base" (R-B) is concerned, since all "users"
are conducting a form of "auxiliary" operation to remotely control
and use the R-B, ALL of these users ARE "control operators" of
the remote station. Therefore, since they are all a part of the "system",
all of them must conduct their operations on authorized "auxiliary"
frequencies above 222 MHz. A different way of looking at a remote-base is to first look at your
own home station. If you allow another Amateur to operate your station while
you aren't around, then HE IS the control operator for your station (and
he must, of course, have your permission to be its control operator - you
wouldn't allow just any unknown Amateur to wander into your station whenever
he pleased and start using it, without your express permission). Now, if
your station is, instead, a remotely controlled station, and another Amateur
is using it, then he is still a control operator. He's just doing it by
remote control, by one of the forms of "auxiliary" operation as
described above. So, THERE IS NO SUCH THING AS AN "OPEN" REMOTE
BASE - ALL users must be specifically authorized by the licensee of the
remote station as designated control operators. However, there is no prohibition
against more than one control operator at a time from using your remote-base.
Several of your friends who are all authorized to use your station, could
be on at the same time talking to each other, or to other stations via your
remote-base. By the way, all of these same principals also apply to F.C.C.-licensed
club stations - just replace the word "licensee", above, with
the word "trustee". A typical "remote-base" "system" these days consists
of the remotely located station (for instance, a mountain-top situated H.F.
kilowatt with rotating beam, etc.), a UHF "auxiliary" "down-link"
to bring the remote H.F. receiver's signals back to the control operator,
and a UHF "auxiliary" "up-link" to carry the control
operator's control signals and his voice up to the remote H.F. transmitter.
But, the remotely controlled station might also include remotely-tuneable
6-Meter and 2-Meter FM radios. And the "down-link" usually re-transits
all of the signals from the "up-link", so to most outsiders, what
they hear sounds just like a repeater! This is where much of the confusion
between "repeaters" and "remote-bases" sets in. It is important to note that even though you might have permission to
use someone else's remote-base station, or a club's remote-base, you, as
the control operator, may only operate that station on frequencies which
your license class permits. There is no difference than if you were sitting
right in front of the transmitter. If you look at the Rules regarding the frequencies available for the
different types of station operation, you will conclude that there is no
such thing as a legal "remote-base" which uses frequencies anywhere
in the 2-Meter band for the "up-" and "down-links".
These "things" that go from 2-Meter FM to 10-Meter FM, or 2-Meter
FM to 6-Meter FM, can only be called "repeaters", and they are
only legal if BOTH ends are within authorized repeater segments of both
bands. Repeater operation (including all input and output frequencies) is
prohibited on ALL of the M.F. and H.F. Amateur bands, except the top end
of 10-Meters. Likewise, there is no such thing as a legal 2-Meter FM to
75-Meter "remote-base", since the auxiliary up- and down-links
MUST all be above 222 MHz. There is no F.C.C. Rule which prohibits a remote-base from being used
on any frequency within the 2-Meter band, even on repeater input and output
frequencies if the user of the R-B wants to use it to talk thru a distant
repeater. Or, the remote-base could be set up on 2-Meter SSB at the bottom
end of the band, or even on the satellite frequencies between 145.80 and
146.00 MHz, etc., as long as the control and voice "auxiliary"
links to and from the remote-base are above 222 MHz. And there is no Rule which prohibits you from setting up a repeater from
some 2-Meter simplex frequency to 52.525 MHz, as long as the frequency used
on 2-Meters is within the authorized repeater sub-bands (52.525 MHz IS within
the authorized 6-Meter repeater sub-band). But remember, this is a repeater,
not a "remote-base". Of course, gentlemanly consideration of other
users on these frequencies, who may not be interested in using your "repeater",
and appropriate frequency coordination, must be considered. By the way, ALL repeater inputs and outputs must be confined to the authorized
repeater sub-bands, including balloon-born repeaters, temporary or portable
repeaters, etc. I've recently read of high-altitude balloons which carried
repeaters operating on frequencies which were not within the authorized
repeater portions of the 2-Meter band. And I've heard of so-called "links"
for repeaters in the 145.50 - 146.00 MHz portion of the band. These are
all illegal! The FRC thanks The Mid Atlantic FM and Repeater Council for the use of this page. Latest update: 16 June 2001 |