Derivated versions

Here you can find other works and versions related with this App. Most of them are just the same application but with slight modifications.

Lock-in+PID H

Harmonic version of Lock-in+PID. It includes a harmonic lock-in up to 50 kHz, PID filters and lock control.

This version of the App doesn’t include the square Lock-in. That frees some “physical surface” of the FPGA to implement other features.

The new features are:

• Modulation added on outputs: In the Auxiliar tab of the Lock-in instrument you can switch on/off the modulation signal cos_ref to be added to the signal already chosen for each port. A -1 value means off and any other value is the relative amplitude with respect to 8191 int == 1 Vpp.
• Enhanced amplification: The X and Y signals can now be amplified by x524288 (x512k). This enables the possibility to measure signals that are far below the resolution limit (~1V/8192).
• NOW WORKS IN RP 2.0 ECOSYSTEM since v0.3.9. Version 0.3.10 fixed some bugs related with the new 2.0 ecosystem.

The lower physical surface load may correct some cross-talking problems between signals that happened on some devices in the Lock-in+PID App.

The source code can be found in the github rp_lock-in_pid_h repository.

Downloads:

• LAST VERSION
• Old versions

• All releases are also available in github
• ChangeLog in the project page

Lock-in+PID H2

Based on Lock-in+PID H, this version includes two lock-in demodulators that share the same local oscillator, PID filters and lock control.

Features:

• Two lock-in amplifiers
• In-phase and quadrature demodulation
  • Demodulation for arbitrary phase
  • Demodulation for double and triple frequency
• Two PID filters, for loop back stabilization
• Ramp/Scan controller for response analysis
• Lock control for automatic scan-stop / PID start
• Streaming system for continued acquisition of two channels
• Remote control through HTTP API

The source code can be found in the github rp_lock-in_pid_h2 repository.

Lock-in+PID H HF

High Frequency version of Lock-in+PID H. It is a copy of that project with only one change: the harmonic modulation signal frequency can be set from 60 Hz to 1 MHz.

The source code can be found in the github rp_lock-in_pid_h_hf repository.

Derivated works from other authors

Harmonic Lock-in+PID with 3 PIDs

Some improvements made by stefanputz, accessible in the github repo.

Other apps

Looking for more? Check out other Red Pitaya apps I’ve developed.