College Station, Texas, U.S.A. • Brazos County • EM10to
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Several repeaters are operated by W5AC.
W5AC's main repeater transmits on 146.820 MHz and receives on 146.220 MHz. Look here for frequently asked questions about repeaters.
The repeater requires a subaudible tone of 88.5 Hz. Tone must always be transmitted at this time. The repeater also encodes a tone of 131.8 Hz (changed in 2003 due to proximity to another repeater).
The repeater radio is a GE Mastr II Executive, with Wacom duplexers and a 30 amp Astron power supply. The controller is an ACC RC-85. It is located on the 13th floor of the O&M Building, on TAMU Main Campus. Click here for pictures. The antenna is a Hustler model G6-270R dual-band antenna, on the roof. This gives a height above ground around 160 feet. The repeater radio puts out 40 watts and has about a 30 mile range with a 50-watt mobile or about 5-7 miles with an HT and a "rubber duck" antenna. There is currently no emergency power capability. The repeater and autopatch are "open" for use by any amateur radio operator.
Autopatch - The "82" repeater also has an autopatch, or phone patch. The autopatch is open - the autopatch codes may be used by anyone and told to anyone, with one exception - the phone patch is NOT to be given out over the air. Direct access "speed dial numbers" to local law enforcement are provided to dues-paying members with the autopatch codes. Go here for guidelines on using the patch.
Joe, N5PYK, has generated a repeater coverage based on a 50W mobile rig. Empirical test suggest that this is pretty close to the actual coverage. Click on the map to open a larger version.
It very closely approximates where a 50W mobile can get into the repeater (assuming 5/8 wave antenna).
Blue areas are going to be fairly scratchy in a mobile environment Pale green (-110) areas will have some white noise and fluttering Medium green (-106) and "hotter" colors will pretty much be full quieting.
One can estimate outside handheld coverage by the areas of GREEN. Note that this represents dead-band coverage. When there is a band opening, usually due to atmostpheric events, coverage will be even greater.
We now have a new PC in the shack running Fedora Core 6, and a new program called Svxlink. Svxlink is a full repeater controller that has an Echolink module built into it (It also talks with a European accent). Since the software is different, there will be a slight learning curve to using the machine, but the basic instructions are below.
Frequency is 443.050 MHz, PL is 88.5 Hz
Echolink is now a sub-program within the repeater itself.
Use DTMF 2# to start Echolink
To connect to another echolink node enter the node number followed by the # sign.
To disconnect the node your press the # sign again.
If you press the pound sign once more, you will exit out of the echolink program. (Just press 2# to start echolink back up.)
W5AC also maintains an Automatic Position Reporting System digipeater. The frequency is 144.39 MHz for transmit and receive, the normal frequency for APRS. It is located on top of the Richardson Building on TAMU Main Campus, with a height above ground of about 150 feet. It transmits at 5 watts. Click here for pictures.
APRS-equipped hams transmit location info several times an hour; when our digipeater receives this signal, it re-transmits it a moment later so that it can be received over a wide area. When these APRS signals enter an IGate, they are translated and posted on the internet here. Our "callsign" for this findu.com system is W5AC-2.
APRS can be used for things besides finding the exact position of a single amateur radio operator. For example, here is our county's current National Weather Service radar with APRS stations overlayed on it, and here are some spacecraft in orbit. APRS maps may also include non-moving objects, storm shelters, runners in a marathon, hurricanes and weather warnings, or even a virtual chess board in the middle of the Gulf of Mexico, just to name a few.
Look for us somewhere in the 440 MHz band on packet radio soon!
Historical transmissions by W5AC are included on the history page.