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The last few days, I performed several magnetic injections in the central building. The new Bobinone was used as a coil, now mounted on a ~2 m high tripod. The lines are generated using the new CaNoise calibration server (see channel Ca_NI_noise) and are sent via the NI DSP (see Sc_NI_LoopIn) to a free DAC channel by setting the gain cal_user to 1. Line amplitudes were optimized to almost saturate the amplifier (line amplitudes = 1, volume knob of the amplifier = 5), frequencies ranged from 5 to 198 Hz. The coil was placed on the balcony above the DAQ room (fig 1) and on the lower balcony (fig 2) with the coil axis pointed in various directions:

930531915 DAQ roof, coil axes towards BS
930698623 DAQ roof, coil axis perpendicular to BS
930834757 DAQ roof, coil axis vertical
930838489 lower balcony, coil axis towards BS
930841599 lower balcony, coil axis perpendicular to BS

At low frequencies, the lines are well visible in B1, see fig 3. With an integration time of 10 minutes, lines up to 200 Hz can be recovered from the noise. Further analysis will follow later. These injections should be repeated at the two end-buildings.

On request of Dominique, I also injected some lines around 165 Hz with the coil placed next to the Detection tower, see fig 4. Start of injection around 930845553. These lines were probably too strong (very nice upconversion), so I launched another injection with 20 times lower amplitude around 930850050.