SRS Labs SR850 User manual

SR850 OFFSET AND LINE NOTCH ADJUST
(P101, P102, P103, P201, P202, P221, P222)
OFFSET ADJUST:
Note: Adjust pots as low as possible
VoltageOffset(P101)
1. Reset the unit by turning ON the unit while pressing the setup key
2. Set the Lock-in using the follow ing settings:
-sensitivity = 100mV
-Oct = 24 dB
-R display / X output
-θdisplay / Y output
-Amplitude = 0.004 V
-Frequency = 1.000 Hz
3. Adjust P101 to make R (channel one display) less than 10 mV. (R<10 mV)
4. Change Sensitivity = 10 mV and adjust P101 again to obtain a R<1display.
5. Change the Sensitivity = 1 mV and adjust P101 to get a R < 0.02 display.
CMRR Offset (P102)
1. Reset the unit. (A quick reset will do. You can do this by turning the unit ON while pressing the local key)
2. Connect a T-connector on Sine output and connect a similar length cable to A/I and B inputs. Connect thosecables
to the T-Connector on the Sine output.
3. Set the Lock-in using the following setting:
-Sensitivity = 2 mV
-Turn on the Sync Filter ON (Sync < 200 Hz should light up)
-A-B input
-Oct = 24 dB
-DC couple
-R display / X output
-θdisplay / Y output
-Amplitude = 1.000 V
-Frequency = 100.00 Hz
4. Adjust P102 to obtain a R < 0.2 mV.
5. Then change the sensitivity to 200 µV and adjust P102 again to get a R < 2µV
VoltageOffset(P101)
1. Disconnect all the cables and reset the unit.
2. Set the following:
-Sensitivity = 1 mV
-Oct = 24 dB
-R display / X output
-θdisplay / Y output
-Amplitude = 0.004 V
-Frequency = 1.000 Hz
3. Adjust P101 to obtain a R < 0.02 mV display.
Current Offset (P103)
1. Settings:
-Sensitivity = 100 mV
-Oct = 24 dB
-I (106) input
-DC couple
-Ground
-R display / X output
-θdisplay / Y output
-Amplitude = 0.004 V
-Frequency = 1.000 Hz
2. Adjust P103 to get a R < 10 nA display.
3. Change Sensitivity = 10 mV and adjust P103 to make R <1 nA.

4. Change Sensitivity = 1 mV and adjust P103 to get R < 0.02 nA .
LINE OFFSET ADJUST:
Note: Adjust pots as low as possible.
Line Notch (60 Hz, Domestic / 50 Hz, Foreign)
1. Connect A input and Sine output with a cable and reset the unit.
2. Set the following settings:
-Sensitivity = 1 V
-Sync < 200 Hz = ON
-Oct = 24 dB
-Line notch
-R display / X output
-θdisplay / Y output
-Amplitude = 1.000 V
For 60 Hz, Domestic:
-Reference Phase = 0.234°
-Reference Frequency = 60 Hz
For 50 Hz, Foreign:
-Reference Phase = 0.246°
-Reference Frequency = 50 Hz
3. Adjust P221 and P222 to make θ=0° or 180 ° and R > 20 mV
•Hint: Adjust P222 to make R > 20 first then adjust P 221 to make θ= 0° or 180° (+/-0.1°)
4. Adjust P222 to make R < 10 mV
5. Set Sensitivity to 10 mV and adjust P222 to make R < 1 mV. If you cannot make it less than 1 mV, tweaking P221
will help and going back and forth between the two to meet the condition.
2xLine Notch (60 Hz, Domestic / 50 Hz, Foreign)
1. Set the following settings:
-Sensitivity = 1 V
-Sync < 200 Hz = ON
-Oct = 24 dB
-2 x Line notch
-R display / X output
-θdisplay / Y output
-Amplitude = 1.000 V
For 60 Hz, Domestic:
-Reference Phase = 0.246°
-Reference Frequency = 120 Hz
For 50 Hz, Domestic:
-Reference Phase = 0.229°
-Reference Frequency = 100 Hz
2. Adjust P201 and P202 to make θ=0° or 180 ° and R > 20 mV
•Hint: Adjust P202 to make R > 20 first then adjust P 201 to make θ= 0° or 180° (+/-0.1°)
3. Adjust P202 to make R < 10 mV.
4. Set Sensitivity to 10 mV and adjust P202 to make R < 1 mV. If you cannot make it less than 1 mV, tweaking P221
will help and going back and forth between the two to meet the condition.