AQS (OneBay)
The Acquisition Control System (AQS)
has multiple digital and RF/AF analog functions. On the left hand
side of the AQS, space is assigned to house 8 thin digital boards.
In the center and the right hand side, 8 slots are reserved for
analog RF-shielded cassettes. Pulse programs run on the digital
boards and real time control commands are then transferred to the
SGU’s in the analog section.
The CCU runs as a "diskless UNIX" client and controls
the TCU3, up to 4 FCU3, the RCU and the GCU. The user’s pulse
program runs on the TCU3. Timing, amplitude, phase and frequency
data is transferred from the TCU3 to the FCU3’s. In each single
channel of the FCU3’s, shape lists are selected and transferred
as digital data to each corresponding SGU, together with the timing
data from the TCU3. A high speed 560 Mbit/s LVDS link connects FCU3’s
to each SGU. A custom designed IC on the SGU generates all RF phases,
frequencies as well as shapes and levels of transmitter pulses.
Pulses are routed and fed to external linear amplifiers.
The NMR signal is mixed down to audio frequency in the RX22 receiver
system and then converted to digital data by the ADC. The local
oscillator frequency is also generated in the SGU. Digitized NMR
signals are fed to the RCU which performs real time digital filtering
and accumulation. The optional GCU generates the gradient shapes
for GRASP experiments. |
BSMS/2
The BSMS/2 unit provides NMR sample control
(SLCB), shim (SCB) and H0 current (LCB)
control, houses the digital lock (LTX, LRX),
the Variable Temperature Unit (VTU) and the
optional gradient amplifier (GAB). |