# Python : Lock in amplifier : how to set local oscillator's amplifier?

**URL:** https://forum.liquidinstruments.com/t/python-lock-in-amplifier-how-to-set-local-oscillators-amplifier/813
**Category:** Software & APIs
**Created:** [September 20, 2023, 8:39am UTC](https://forum.liquidinstruments.com/t/python-lock-in-amplifier-how-to-set-local-oscillators-amplifier/813 "2023-09-20T08:39:41Z")
**Posts on this page:** 2
**Page:** 1

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### Author: ![moku\_go\_user](https://avatars.discourse-cdn.com/v4/letter/m/8e7dd6/32.png) [@moku\_go\_user](https://forum.liquidinstruments.com/u/moku_go_user)
#### Post date: [September 20, 2023, 8:39am UTC](https://forum.liquidinstruments.com/t/python-lock-in-amplifier-how-to-set-local-oscillators-amplifier/813/1 "2023-09-20T08:39:41Z")

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![python_moku_go_LIA](https://canada1.discourse-cdn.com/flex035/uploads/liquidinstruments/original/1X/cc0b4d4beecac31438c74ac115ef39acbf5d410a.jpeg)

hello. I am a user of Moku:Go (with Lock in amplifer).

> **[Examples for Python | Moku API](https://apis.liquidinstruments.com/examples/python/#lock-in-amplifier)**
>
> Documentation for the Moku Scripting API for Python and MATLAB

I have some questions about running LIA in python using the code in the link above.

First: i.set\_filter error occurs.

Exception occurred: [‘Unable to set corner\_frequency to desired value. Coerced value: 999.997206’]

Second: I configured it as Internal and Demodulation as shown in the image, but I don’t know how to control the local oscillator’s amplifer in python.

Please reply.

Thank you.

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### Author: ![moku\_go\_user](https://avatars.discourse-cdn.com/v4/letter/m/8e7dd6/32.png) [@moku\_go\_user](https://forum.liquidinstruments.com/u/moku_go_user)
#### Post date: [September 21, 2023, 9:11pm UTC](https://forum.liquidinstruments.com/t/python-lock-in-amplifier-how-to-set-local-oscillators-amplifier/813/2 "2023-09-21T21:11:36Z")

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I have solved the problem. Like this .!!

1st. problem :  
i.set\_filter(100, slope=‘Slope18dB’, strict=False)

2nd problem:  
i.set\_aux\_output(500, 0.2) \<— Even if the output mode is demod, the amplitude value is controlled with set\_aux\_ouput.

> [@Corner frequency cannot be set when using Moku:Go's lock-in amp function with matlab](https://forum.liquidinstruments.com/t/corner-frequency-cannot-be-set-when-using-moku-gos-lock-in-amp-function-with-matlab/801/1):
>
> An error occurs when using the instruction statement set\_filter in the sample program lock\_in\_amplifier\_basic.m using the lock-in amplifier function in matlab on the LIQUID INSTRUMENT website. The error is as follows. Unable to set corner\_frequency to desired value. The coerced value depends on the corner frequency to be set, but no matter what value is set, an error occurs. I would like to know how to solve this error, as I am not familiar with English. Finally, a sample program for this err…