Tutorial, Teardown & Experiments with Stanford Research SR530 Lock-in Amplifier - Page 1
Forum section: electronics / testgear

author: Hugoneus
author_rank: Frequent Contributor
timestamp: September 04, 2017, 03:55:01 am
content: There are some neat experiments in this tutorial which I hope you like.You can watch it here: [49 Minutes]youtu.be/rzzliN_vTKsMore videos at The Signal Path:www.TheSignalPath.com

author: TheSteve
author_rank: Unknown
timestamp: September 04, 2017, 08:03:05 am
content: "And here I'm using centimeters, because I'm not insane" - awesome!!!

author: stevelup
author_rank: Regular Contributor
timestamp: September 04, 2017, 08:16:12 am
content: I enjoyed this one because I understood what you were doing and how you were doing it. Which isn't usually the case

author: Rbastler
author_rank: Frequent Contributor
timestamp: September 04, 2017, 10:43:40 am
content: Brought back bad memorys from a lecture at university about some really difficult stuff, that I coudnt link to anything.Now I can and learning it then will look much more usefull/easier now, since now it has a known purpose, other than just "youll see later whats its good for".Sent from my A0001 using Tapatalk

author: HighVoltage
author_rank: Super Contributor
timestamp: September 04, 2017, 04:50:33 pm
content: Very nice and informative video.Thank you!

author: cat87
author_rank: Regular Contributor
timestamp: September 05, 2017, 09:27:04 am
content: Thanks for the video. Very informative. I had no idea something like this even existed

author: Hugoneus
author_rank: Frequent Contributor
timestamp: September 05, 2017, 05:00:36 pm
content: Quote from: cat87 on September 05, 2017, 09:27:04 amGlad you liked it.

author: Kleinstein
author_rank: Super Contributor
timestamp: September 05, 2017, 05:40:18 pm
content: A lockin is a really powerful instrument. The two experiments are really nice. However the time constant at the Lockin is chosen rather long - thus a sluggisch response. It could have been done with faster response - despite of increasing noise.It might have been interesting to also look at the monitor output for the second experiment. This might have even replaced the measurement with the DMM.The SR530 is still a classical analog one. Modern Lockins usually do much of the operation in digital - so the block diagram looks different. I am somewhat surprised the SR530 did not include an internal function generator. Usually there also is a simple generator included.

author: CalMachine
author_rank: Frequent Contributor
timestamp: September 06, 2017, 01:35:22 am
content: Great video!I've had the pleasure of calibrating many of these unitsThey are a great unit to work with!

author: xrunner
author_rank: Super Contributor
timestamp: September 06, 2017, 01:41:10 am
content: Oh cool - I used these in the IR lab where I worked before I retired. Nice piece of gear.

author: Hugoneus
author_rank: Frequent Contributor
timestamp: September 06, 2017, 01:18:44 pm
content: Quote from: Kleinstein on September 05, 2017, 05:40:18 pmIt does have an internal oscillator! I just didn't use it to avoid causing confusion. The internal source is accessible from the back.

author: Kleinstein
author_rank: Super Contributor
timestamp: September 06, 2017, 02:48:21 pm
content: If one has time, one can really go down in bandwidth and this way down in noise. I have once used a similar lockin with additional external digital integration over 1000 seconds to look at a really small signal. It just took a weekend to get a curve. Using digital integration (e.g. reading via GPIB) can cut down on the waiting time for the signal to stabilize, so less time is lost.For an experiment like the laser - LED one, the better mode is to use just one channel and adjust the phase before. Using the amplitude / phase modes is kind of easy to use, but gives slightly higher noise. So this experiment could also be done with a simpler single channel version if the lockin. The dual phase version has very little advantage in this case.

author: SilverSolder
author_rank: Super Contributor
timestamp: November 04, 2019, 11:57:56 pm
content: Awesome video. Is there a schematic available for this instrument?

author: wishboneash
author_rank: Contributor
timestamp: August 28, 2022, 12:45:59 am
content: Looking for the schematic myself. I have a big error in the current gain (around 20-30%) but voltage gain is fine (a few percent error at most). The description from the manual states -<<When the input selector is set to current, the input to the pre-amp comes from the output of the current to voltage converter, 1/2 U102. U102 is a low voltage-noise bipolar op amp. Q102 serves as an input buffer to provide low current-noise to the input. The op amp always maintains a null at the gates of Q102 thus providing an input impedance of 1KΩ (R128). The input current is converted to a voltage by R135 and the op amp. Q103 bootstraps out the summing junction capacitance of Q102.>>Seems like the 1kohm is a terminating impedance and input current is buffered by an N ch FET and sent to a TIA with a feedback gain of 1e6 (R135). I'll open it up and see if I can find out what's going on.

author: _Wim_
author_rank: Super Contributor
timestamp: August 28, 2022, 06:59:57 am
content: This documents included the schematic of the SR510, which should be fairly similar. Not the best scan, but better than no schematics...Had to split the zip in 4 parts to attach it here. Files named Lockinamplifier_SR510.z0x.zip need to be renamed to Lockinamplifier_SR510.z0x to unzip (forum only allows to attach zip files)

author: _Wim_
author_rank: Super Contributor
timestamp: August 28, 2022, 07:03:39 am
content: Quote from: _Wim_ on August 28, 2022, 06:59:57 am

author: _Wim_
author_rank: Super Contributor
timestamp: August 28, 2022, 07:05:16 am
content: Quote from: _Wim_ on August 28, 2022, 06:59:57 am

author: _Wim_
author_rank: Super Contributor
timestamp: August 28, 2022, 07:07:12 am
content: Quote from: _Wim_ on August 28, 2022, 06:59:57 am

author: wishboneash
author_rank: Contributor
timestamp: August 28, 2022, 10:57:19 pm
content: Unfortunately page 82 which contained the input section was not in good shape. Some reverse engineering is in orderThe rest of the schematics are good. Thanks.

author: _Wim_
author_rank: Super Contributor
timestamp: August 30, 2022, 06:56:38 pm
content: Quote from: wishboneash on August 28, 2022, 10:57:19 pmI does seem that once upon a time these were delivered together with the unit in a printed format. Did you already ask SRS for a copy? I had good luck with Signal Recovery (Ametek) in the past

author: Ice-Tea
author_rank: Super Contributor
timestamp: August 30, 2022, 07:03:44 pm
content: Got one of these but by the looks of it the LCD is all over the shop (analog meter seems fine). If anyone is looking for a project to outdo The Signal Path: feel free to drop me a PM ;-)

author: wishboneash
author_rank: Contributor
timestamp: September 01, 2022, 08:21:11 pm
content: Quote from: _Wim_ on August 30, 2022, 06:56:38 pmI contacted SRS and they suggested to buy hard copy from outside vendors for about $100.

author: maxwell3e10
author_rank: Frequent Contributor
timestamp: September 01, 2022, 08:25:14 pm
content: I couldn't find a printed SR530 manual, but found SR830. Here is the page with the input amplifier. Perhaps it is similar enough.

author: Kleinstein
author_rank: Super Contributor
timestamp: September 02, 2022, 11:58:33 am
content: The SR830 input stage is more conventional. The current to voltage converter uses just a single OP-amp.