Teledyne GFC 7001EM Adjusting the Sync/Demodulator, Circuit Gain, Adjustment Made Here

Troubleshooting & Repair Model GFC7001E Carbon Dioxide Analyzer

13.6.3.2.Adjusting the Sync/Demodulator, Circuit Gain

To adjust the sync/demodulator circuit gain:

1.Make sure that the analyzer is turned on and warmed up.

2.Set the analyzer display to show the STABIL or CO STB test function.

3.Apply Zero Air to Sample Inlet of the analyzer.

4.Wait until the stability reading falls below 1.0 ppm.

5.Change the analyzer display to show the CO MEAS.

6.Remove the Sync/Demod Housing

Remove the two mounting screws.

Carefully lift the housing to reveal the sync/demod PCA.

Housing Mounting

Screws

Sync/Demod

PCA Housing

Optical Bench

Figure 13-19: Location of Sync/Demod Housing Mounting Screws

7. Adjust potentiometer VR1 until CO MEAS reads 4500 mV ± 300 mV

VR1

Adjustment Made Here

Figure 13-20: Location of Sync/Demod Gain Potentiometer

Teledyne Analytical Instruments 303