Tsunami - Beckman Institute Laser Resource Center

Tsunami
1
r \
r -,
240V
MiTlMlNG LOOP NM
ADJUST MON Om
0 0 0
PHOTODIODE PHOTODIODE REF REF REF- 8 80 MHz
TO HEAD OUT IN IN DUT OUT
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Figure 8-3: Model 3930 Electronics Module Rear Panel Controls and Connections
EXT TIMING ADJUST connector-provides connection for an external
error input signal (supplied by user). Input impedance is 20 kQ. Signal
sensitivity is approximately 7.5 mV/,. This signal is summed with the
signal from the coarse and fine TIMING controls (Figure 8-4).
LOOP MONitor connector-provides a buffered feedback signal for
monitoring on an oscilloscope or volt meter. The best system performance
is achieved when the laser is adjusted for the smallest output signal.
Output impedance is 1 kQ. Signal sensitivity is approximately 100 mV/,.
Output voltage range is approximately f 15 V.
Ann OUT connector-provides a fixed, buffered, 10 Hz triangle wave
from the internal sweep generator for driving the horizontal sweep on an
oscilloscope. The signal is present even when the sweep generator is not
selected on the front panel. Output impedance is 1 kQ.
PHOTODIODE OUT connector-provides a buffered Tsunami laser
photodiode output signal for monitoring on an oscilloscope. Output
impedance is 50 Q at -10 dBm for a sine wave. dBm is dF3 with respect to
one rnilliwatt:
I
-
To convert to watts:
dbm
watts = .001 . lom
To convert to volts, peak-to-peak: voltspp = 2 . fi -
PHOTODIODE IN connector-attaches to the LTC PD photodiode output
connectors on the Tsunami laser input bezel. This feedback signal is used
by the Lok-to-Clock system to lock the Tsunami cavity to a set frequency.
Input impedance is 50 Q at -10 dBm for a sine wave.
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