50 milli-Farad 3000 Watt-sec Capacitor Bank

This capacitor bank is currently wired with 22 2200uF capacitors in parallel. Maximum DC voltage is 350v and the total energy stored is approx. 3000 watt-secs (Joules). A discharge resistance low enough to achieve a 1nS pulse equates to 3TW peak pulse power. However, the ESR of the capacitors alone will limit the discharge time to around 100us, hence the peak pulse power will only be about 22MWatt. To confirm the marked value of the caps (2.200uF) a 17.5v DC supply was connected to one via a 100k resistor and the time taken to charge to 1v was measured. 15sec, gives a dv/dt=1/15 v/sec. The charging current (fairly constant) = 17/100k and the capacitance is therefore:
C = i (const)/dv/dt = 17/100k / 1/15 = 17 * 15 / 100000 = 2550 uF

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GNU Radio Waterfall and CW Filter

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Splunk Cheat Sheet (Linux)

1. set root's password: sudo su passwd root Enter new UNIX password: < new_root_password > Retype new UNIX password: < new_root_password > passwd: password updated successfully # su - 2. Remove any existing Splunk directories & create user etc: # rm -rf /opt/splunkforwarder # userdel -r splunk # this will remove as above if user splunk's home directory # groupadd siem # useradd -g siem -s /bin/bash -d /home/siem -m siem # vi ~/.profile # chage -I -1 -m -0 -M -99999 -E -1 siem If above fails because of multiple passwd fails: # pam_tally --reset check with #chage -l siem # uname -a # check OS version # dpkg -i splunk-4.3.1...........intel.deb # chown -R siem:siem /opt/splunk # su - siem : $SPLUNK_HOME/bin/splunk start --accept-license : $SPLUNK_HOME/bin/splunk edit user admin -password newpassword -role admin -auth admin:changeme 3. vi ~/.profile (as follows) (OR .bash_profile) # ~/.profile: executed by the command interpreter for log

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