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FMCG/Experimental setup: Difference between revisions
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# Also turn on the high voltage supplies for the heaters. Those are the two Tektronix PWS2721 supplies in the bottom right corner. Hit the push button to turn them on, and the light-up ON/OFF to enable the output. If any of the heaters are enabled, you should see current being drawn from the supplies.
# To enable the heaters, connect a function generator to the red BNC port on the front of the heater box, and set the correct parameters on the function generator. I've been using a 8V sine wave at 150.700 kHz (the small frequency offset takes care of low-frequency aliasing issues). Then flip up the ON/OFF switches on the channels you wish to heat up. The voltage can be adjusted on a per-channel basis by adjusting the gain pot on each channel. Again, you should see the current drawn from the Tektronix supplies change when you enable/disable/change the gain on each channel.
# Make sure the heater fan is enabled. There is a small aluminum box with an on/off switch on top of the function generator. The cable is labeled '''Heater Fan'''. The fans have a distinctive whine when they're turned on, so it should be easy to tell that they're enabled. There is another similar looking box which provides +5 V for the LCD screen on the front of the main control box. Make sure this is enabled as well.
# Return to the front side of the array and enable both of the lasers using the SRS LDC501s (left: '''pump''', right: '''probe'''). TEC first, laser diode second. The devices have been set up to not allow laser output unless the TEC has been enabled first, anyway. Both lasers are fiber-coupled into their respective TAs, so by activating the diodes, you're not yet sending any light into the room.
# Set up an oscilloscope. Use one of the long power cables connected to one of the rack power strips (bottom right on the back of the rack) to ensure that the scope shares a ground with the rest of the electronics. Connect a bundle of four BNC cables between the green BNC ports on the FPGA breakout box and the scope. The green BNC ports are in ''parallel'' with the FPGA inputs, and will provide a "monitor" for the data the FPGA can record. The switches beneath these ports determine the signal that is being sent to the FPGA and scope: The default position is '''down''', which passes the detector signals via the DS345 I-V converters.
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