Справочник Пользователя для Teledyne gfc 7000ta

 

Teledyne Analytical Instruments 

203 

 

Thermo-Electric 

Cooler 

Control Circuit 

Amplifiers 

Dark 

Switch 

Photo-

detector 

Pre Amp 

E-Test 

Generator 

 
 

M/R Sensor

 

Segment 

Sensor 

E Test Control

 

Dark Switch 

Control 

X10 Clock

 

Phase Lock

 

E Test A Gate 

Dark Test Gate 

X1 Reference

 

Segment 

Status LED 

Phase Lock Warning 

M/R 

Status LED 

Segment Clock

 

E Test B Gate 

Measure Gate 

Measure Dark Gate 

Reference Gate 

Reference Dark Gate 

56V 

Bias 

Variable 

Gain Amp 

From GFC 
Wheel 

From CPU 
via Mother 

Board 

Signal 

Conditioner 

Signal 

Conditioner 

10 

x10 

TEC Control 

PHT DRIVE 

 

 

The signal emitted by the IR photo-detector goes through several stages of amplification before it can be 
accurately demodulated.  The first is a pre-amplification stage that raises the signal to levels readable by 
the rest of the synch/demod board circuitry.  The second is a variable amplification stage that is adjusted 
at the factory to compensate for performance variations of mirrors, detectors, and other components of 
the optical bench from instrument to instrument.   

The workhorses of the sync/demod board are the four sample-and-hold circuits that capture various 
voltage levels found in the amplified detector signal needed to determine the value of CO2 MEAS and 
CO2 REF

.  They are activated by logic signals under the control of a compact programmable logic device 

(PLD), which in turn responds to the output of the Segment Sensor and M/R Sensor described in 
Figure 10–11.