Sodankylä Geophysical Observatory
Ionosonde Instrument Description
Modified IS-14 sounder (in operation until 16. Nov 2005)
- Alpha-Wolf (in operation since 16. Nov. 2005)
- Normal vertical sounding program:
- Usually 6 ionograms per hour (higher resolution possible)
- RWD program:
- Same as normal program.
- Time used in scaled data:
- EET (30 deg E, UT + 2 h).
- Frequency range:
- 0.5 - 16 MHz
- Sweep time:
- about 30 seconds
- Peak power:
- 150 W nominal (actually much less is used)
- Gain control:
- Fixed gain. Direct Tx rejection is about 120 dB.
- Transmitter: Rhombics in 64 m mast.
- Receiver: 8 active orthogonal loop antennas ("phased array").
- O-mode ionogram is currently published on web in real-time.
Real-time ionograms have 90dB dynamic range. Virtual range up to 3000km.