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Current radars/transmitters in the AO vicinity and their parameters

Gracias a Phil Perillat y Karen O'Neil

See also the various useful info on Phil's home page, especially his radar info page, or his G-ALFA presentation on RFI and how ALFA might deal with it

Fractional Occupancy
(% of time seen while observing)
Strength (typical)
(% Tsys)
Length & Frequency of Burst
1217, 1227.5, 1265.0, 1313.0       Pico del Este Radar
1222.32, 1231.28, 1240.24, 1249.2, 1258.16, 1267.12, 1276.08, 1285.04, 1294.00, 1302.96, 1311.92, 1320.88 1329.84, 1338.80, 1347.76, 1356.72, 1365.68, 1374.64, 1383.60, 1392.56 Always in some mode     Puntas Salinas Freq. Hopping Radar. (More info available below)
1241.7, 1246.2, 1256.7 Occasionally     Military - Tethered balloon
1270.9/1289.8 Occasional (and only one of the two freq. at a time) >100% 12s pulse FPS20-93a radar located at Ramey but controlled by the folks at Puntas Salinas
1324,1340 Occasional (only during war games) >100% 2s pulse Naval "landing system"
1330/1350 ALWAYS >100% 400micros pulse FAA Radars (Pico del Este) BLANKER AVAILABLE
1366.3,1382.7 Occasional (only during war games) >100% 2s pulse Naval "landing system"
1371.0,1387.3 Occasional (only during war games) >100% 2s pulse Naval "landing system"
1381.1 Variable 10% - >100% Variable GPS L3 satellites



Other RFI Issues - The PRANG (Puntas Salinas) Frequency Hopping Radar:

This radar runs in the range from 1220 - 1400 MHz and has the potential for completely killing most HI observations at Arecibo. Fortunately, through considerable work by the RFI folks here at Arecibo, an agreement has been made between us and the folks at Puntas Salinas. If a request is put in in advance, Puntas Salinas can restrict the frequencies used to so they do not interfere with your observations. This means you must state on your proposal form that you wish to have coordination with Puntas Salinas. If you do not, there is a good chance PS will be transmitting at ALL of their frequencies. (More info on the PS radar modes can be found at Phil's PS page)

On occasion, although we did request that PS use a particular mode, they may forget to switch to that mode. If this occurs, simply ask the on-duty telescope operator to telephone our contact at PS and ask them to check that they are transmitting in the correct mode. Before doing this, though, be sure to check that the to have the operator help you check that the RFI you are seeing is from Puntas Salinas.

Future RFI Issues at L-band:

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Up: E-ALFA Hardware Previous: SDFITS notes

This page created and maintained by Martha Haynes.

Last modified: Tue May 20 09:42:35 EDT 2003