We refer all potential observers to the discussion of man-made Radio Frequency Interference (RFI) in the OSS. A natural source of interference is the (active) sun. This can be a problem when observing at L-band in the compact (C and D) configurations. The severity fluctuates as a function of the approximately 11 year solar cycle (see Table 3.1). It can only be avoided by observing well away from the sun or by doing sensitive observations at night. While there is little one can do to remove solar interference, its impact can be reduced in the data processing stage (cf. AIPS Cookbook).
| Table 3.1: Solar Maxima and Minima | ||
| Solar Cycle | Min. | Max. |
| 20 | 1964 | 1969 |
| 21 | 1976 | 1980 |
| 22 | 1986 | 1992 |
| 23 | (1997) | (2002) |