SRS Labs Lock-In Amplifier, SR530 manual Status Byte Definition, Configuration Switches

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Status Byte Definition

Bit Meaning

0Magnitude too small to calculate phase

1Command Parameter is out-of-range

2No detectable reference input

3PLL is not locked to the reference

4Signal Overload

5Auto-offset failed: signal too large

6SRQ generated

7Unrecognized or illegal command

Configuration Switches

There are two banks of 8 switches, SW1 and SW2, located on the rear panel. SW1 sets the GPIB address and SW2 sets the RS232 parameters. The configuration switches are read continuously and any changes will be effective immediately.

SW1:GPIB Mode Switches

Bit

Example

Function

1 }

up

GPIB Address Switches

2 }

up

Address 0 to 30 allowed

3 }

up

'up' for bit = 1

4 }

down

'down' for bit = 0

5 }

up

(Most Significant Bit)

6

down

'down' to echo on RS232

 

 

(normally 'up')

7

up

Not Used

8

up

Not Used

If the GPIB mode switches are set as shown in the example column above, then the lockin will be addressed as GPIB device #23, and all GPIB commands and data will be echoed over the RS232 for de-bugging purposes.

SW2:RS232 Mode Switches

Bit 1

Bit 2

Bit 3

Baud Rate

up

up

up

19200

down

up

up

9600

up

down

up

4800

down

down

up

2400

up

up

down

1200

down

up

down

600

up

down

down

300

Bit

Setting

Explanation

4

up

Odd parity

 

down

Even parity

5

up

No parity

 

down

Parity enabled

6

up

No echo (for computer)

 

down

Echo mode (for terminal)

7

up

Two stop bits

 

down

One stop bit

8

 

unused

Eight data bits are always sent, regardless of the parity setting. The most significant bit is always zero.

Example: Bit 1 'down' and all others 'up' for RS232 communication at 9600 baud, no parity, two stop bits, and no echo or prompts by the SR530.

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Contents Model SR530 Page Table of Contents Appendix C Gpib Operating NON-OPERATINGPage SR530 Specification Summary Demodulator GpibFront Panel Summary Enbw Abridged Command List Configuration Switches Status Byte DefinitionSignal Inputs Signal FiltersSR510 Guide to Operation Front Panel SensitivityDynamic Reserve StatusDisplay Select Channel 1 DisplayOutput Output ChannelRel Channel Offset ChannelExpand Channel Rcosø OutputChannel 2 Display Auto Phase Rsinø Output Reference InputTrigger Level Reference Mode Phase ControlsReference Display Time ConstantPower DefaultsLocal and Remote SR530 Guide to Operation Rear Panel Page Command Syntax SR530 Guide to ProgrammingCommunicating with the SR530 Front Panel Status LEDsRS232 Echo and No Echo Operation Try-Out with an Ascii TerminalSR530 Command List LOW Norm HighN1,n2,n3,n4 Page Errors Status ByteBit Reset Trouble-Shooting Interface ProblemsCommon Hardware Problems include Common Software Problems includeSR530 with the RS232 Interface SR530 with the Gpib InterfaceSerial Polls and Service Requests Gpib with RS232 Echo ModeSR530 with Both Interfaces Lock-in Technique Measurement ExampleUnderstanding the Specifications Shielding and Ground LoopsPage Page SR530 Block Diagram Signal Channel Phase Sensitive DetectorsReference Channel DC Amplifiers and System GainCircuit Description Reference Oscillator Demodulator and Low Pass AmplifierAnalog Output and Control ExpandFront Panel Microprocessor ControlPower Supplies RS232 InterfaceGpib Interface Multiplier Adjustments Amplifier and Filter AdjustmentsCalibration and Repair Notch Filters Replacing the Front-End TransistorsAppendix a Noise Sources and Cures Non-Essential Noise SourcesPage Page Case 1 The Simplest Configuration Appendix B Introduction to the RS232Baud Rate Case 2 RS232 with Control LinesStop Bits ParityVoltage Levels Final TipAppendix C Introduction to the Gpib Bus DescriptionAppendix D Program Examples Program Example IBM PC, Basic, via RS232Program Example IBM PC, Microsoft Fortran v3.3, via RS232 Page Program Example IBM PC, Microsoft C v3.0, via RS232 #include stdio.hPage Program Example 4 IBM PC,Microsoft Basic, via Gpib ′INCREMENT X6 Output by 2.5 MV Program Example HP85 via Gpib Documentation Oscillator Board Parts List PC1SW1 DpdtMain Board Parts List BR1BR2 BT1SR530 Component Parts List SR530 Component Parts List 22U MIN PIN DGpib Shielded CX1CY1 FU1MPSA18 SR530 Component Parts List SR530 Component Parts List SR530 Component Parts List SR530 Component Parts List SR530 Component Parts List SPSTX8 4PDTSR513 Assy SR530 Component Parts List Z80A-CPU Static RAM, I.CTIE Anchor TranscoverMica #4 FlatFront Panel Board Parts List RED LD1 LD2LD3 Quad Board Parts List SR530 Component Parts List PC1 SR530 Component Parts List Miscellaneous Parts List SR530 Component Parts List

SR530, Lock-In Amplifier specifications

The SRS Labs Lock-In Amplifier, model SR530, is a powerful tool designed for high-precision measurements in the realm of scientific research and industrial applications. This state-of-the-art instrument excels in extracting small signals from noisy environments, making it an invaluable asset for experiments in fields such as physics, engineering, and materials science.

One of the main features of the SR530 is its ability to perform synchronous detection, which is key to improving signal-to-noise ratios. By utilizing a reference signal, the device correlates the incoming signal with the reference to effectively filter out noise, allowing for the accurate measurement of weak signals that might otherwise be obscured. This process of phase-sensitive detection is fundamental to the operation of the Lock-In Amplifier.

The SR530 offers a wide frequency range, covering from 0.1 Hz to 100 kHz. This broad frequency response allows it to handle a diverse array of signals, making it suitable for various applications including optical detection, capacitance measurements, and in many cases, voltammetry. The device is also equipped with multiple inputs and outputs, facilitating the integration with other laboratory equipment and enabling complex experimental setups.

Precision is further enhanced with its adjustable time constant, which allows users to optimize the response time based on experimental needs. The user can choose time constants from 10 microseconds to 10 seconds, accommodating fast dynamic measurements as well as those requiring stability over longer durations.

Another remarkable characteristic of the SR530 is its digital processing capabilities. The device features a highly accurate digital voltage measurement system, minimizing drift and ensuring long-term stability. Additionally, the use of microprocessors enhances data handling and allows for features such as programmable settings, facilitating automated measurements.

Moreover, the SR530 includes a range of output options, including analog outputs, which can be used for direct signal processing, as well as digital interfaces for integration with computers. This ensures that users can not only capture high-fidelity data but also analyze and display it efficiently.

In conclusion, the SRS Labs SR530 Lock-In Amplifier stands out due to its sophisticated technology, versatile features, and robust performance. Its precision, flexibility, and ease of use make it an ideal choice for researchers and engineers looking to unlock the potential of weak signal measurement in complex environments.