Electron microscope image capture with an oscilloscope

[@didaloca]

You know you've made it when you can say "Take a look at my scanning electron microscope collection."

[@NGC6144]

Chicks really dig electron microscopes. "Can you scan my...?"

[@-danR]

I was the rare individual who was intrigued by junk lying around for collection, outside my university's science departments, a proclivity not shared by my friend. She thought it a bit weird. Fact is, I shoulda been going between classes in a pickup.

[@brentfisher902]

Like I said kids, stay in school, don't do drugs, don't get girls knocked up and you will be able to get a job that will pay you enough to collect scanning electron microscopes. I'm a childfree supremacist myself...

[@frother]

His oscilloscopes are the really impressive collection TBH

[@TheKingofRandom]

You are incredible

[@AppliedScience]

Thanks! I really appreciate it.

[@ezcreations777]

I'm glad you've found this channel too Grant!

[@abdullahkhan8823]

The King of Random you are also incredible I am also your fan as well as I am ben fan you people are founder of real youtube

[@___xyz___]

You are crazy.

[@jonathanrabe3727]

We miss you Grant

[@ev1te759]

Great video Ben, I am glad that we managed to get it shipped from Sweden to the USA. I hope it comes to good use so that all your viewers can appreciate the vintage technology that comes with it! :) /Richard Andersson

[@Afrotechmods]

Amazing. Shirt purchased.

[@jimmysyar889]

Hey there. Add one more comment to the list.

[@w2aew]

Absolutely awesome Ben. Can never get enough of SEM photos, simply fascinating - and I love how the MDO is being used as the data acquisition engine. The HiRes sampling mode, with the amount of boxcar averaging you're getting, is giving you many more bits of vertical (video) resolution. Simply great!

[@AppliedScience]

Alan, thanks so much! I wondered if the Hi-res mode allows the scope to output more than 8-bits of vertical information. It looks like it does from the smallest deltas in the CSV file. Very handy feature!

[@w2aew]

Applied Science Yes, you'll get an extra 0.5 bits each time the # of bits averaged doubles. Thus, If Hi-Res averages 2 bits, you get 8.5 bit resolution. If it averages 4 bits, you get 9 bit resolution, and so on. The MDO3k samples at 5GS/s on a single channel. When you set the record length and horizontal scale, you effectively set the waveform sample rate (reported on the bottom right of the display). The number of samples averaged in hi-res mode is then 5GS/s divided by the indicated waveform sample rate. Thus, if the waveform sample rate says 500MS/s, then 10 samples are averaged to create each waveform sample point, giving you just over 9.5 bits. Fixed point math hardware limits the progression at some point...

[@jakehenri9608]

I bought your shirt 30 seconds into the video, love your channel. Please keep making super interesting videos forever and ever.

[@AppliedScience]

Thank you!

[@franciscojuretig2963]

Every time I see one of your videos, you amaze me even more. You are certainly inspiring for the rest of us, a complete genius

[@Piridrip]

Those images are amazing. They have such bold tonality while still being illustrative. I think a book with images of this style would be popular.

[@qpae123]

If we had teachers like you in the university, things would have moved a lot faster ! :) Great video !

[@CmdrCorn]

This makes me feel like the laziest man in the world. Being able to problem solve with such practical clarity means your work will always be ahead of the rest, likely in any domain. Applied indeed! Glad I found the channel. SEM has captured my imagination since childhood. Surface opacity makes every image so much more relatable compared to light and optical microscopy. Much more "as if you were there" in the micro world.

[@tamasmihaly1]

Restoring my faith in humanity one video upload at a time. Thank you.

[@PotatoMcWhiskey]

Perhaps you could take scan requests from us laymen and let us glimpse into the microscopic world all around us. Not everyone in the world has the opportunity to use an electron microscope so! Maybe a monthly episode dedicated to showing some of the stuff people requested to be seen? I'd love to see some pollen/plant scans :)

[@AppliedScience]

Yes, I'd be happy to receive suggestions for items to view in the SEM. Pollen is a great idea!

[@NickMoore]

Applied Science What about Diatoms? You could even try diatomacious earth (the insect killing powder) and see if there are any full shells in there.

[@PixelCortex]

Applied Science Please do a butterfly wing! pretty please?

[@Aggrop0p]

How about the grooves of a vinyl record? Or maybe just a regular sheet of paper?

[@dizzious]

Aggrop0p I wonder what kind of audio quality you could get by decoding an SEM image of a vinyl record?

[@Frank-Thoresen]

Just mind boggling how you understand this equipment and use it to its maximum performance and beyond.

[@AppliedScience]

Afrotechmods Thanks, man!

[@DanFrederiksen]

Very nice. Since a SEM can seemingly be a rather simple device with low speed low cost image acquisition electronics and USB interface, I wonder if you might consider seeking venture cap funding and do a kind of makerbot SEM for the people. You could just start it up and pick some people to implement your directives so you don't actually have to do anything.

[@YousifSlaiwa]

Applied Science What is the resolution on the microscope you were shipped? I am in desperate need of a SEM. It would be very cool if you work on Dan Frederíksen's idea. Me and countless other citizen scientists would be all over that.

[@alkeryn1700]

It dont have one by default, it is analog

[@ruphusbau3721]

I did not understand the name microscope sem 80s

[@thekaiser4333]

Is an electron particle or wave?

[@ska24ster]

Honestly ! you are one of the most important scientific brains in the world. Keep going Sir.. and thanks for your efforts

[@yosisoyshi]

Ah! That was very satisfying to watch! I love it when I can actually understand what's going on in an SEM and you let us know how the to convert data into information through your thorough manipulation of the signal.

[@eldenchang]

You show things that I thought are not possible with a 'simple' scope. Very impressive.

[@MSI2k]

Dude, your methods and techniques blow my mind. You're an insane genius.

[@nsharief838]

Hi Ben, Another cool trick you can try with the EM is imaging the internal structure of chamber, like having a mirror inside the SEM. Mount a coin shaped disc with smooth side under the beam. Apply high kV (30kv) on the disc, let it charge up for about 5 mins. Then switch to low kV ( 3kv, or 4). You will see image of chamber, with a sort of fish eye lens effect.

[@darshiess]

This channel even amazes all the other KZbin science channels lmao . I've never seen so many big science channels in just one video

[@VictorFota]

One of the best channels on youtube. I love how dedicated you are and that you are willing to share this for free with us.

[@tehzimmy]

Applied Science This.... is freaking amazing. For the novice tinkerer that does not have access to an SEM, this is a good tutorial on how to perform capture on a NTSC video signal. Very nicely done! I look forward to seeing how you incorporate this with other projects... you alluded to metal sputtering (which I know you've already covered in previous videos) so maybe we'll get some of of these in the future!

[@wizardOfRobots]

I'm totally amazed by your technique and finesse Mr.Ben!

[@MrTheoryboy]

Wow, your channel has some of the most interesting things on the net, and this is one of the most impressive. Bow to you sir.

[@manunamboo]

You are an inspirational scientist, who knows science and can use technology into.

[@Dani128]

Great images and excellent explanation about to set up the oscilloscope to properly capture the frame. I'm glad this perfectly working piece of equipment wasn't just thrown away, unlike so many others.

[@lis6502]

Dude, you are amazing. Not just by collecting this odd stuff and doing videos, but literally walking us through principles of functioning, caveats, physics behind certain devices and processes... Literally i was searching to "how to build microscope out of camera lenses", ended up at AS again being unable to move through whole video. Thank you :D

[@HuskyMachining]

This is my favorite channel on KZbin. Don't stop the great videos!

[@JAKOB1977]

Its a shame you have not come up with many more videos of this fascinating device here in the last 4 years..your thumbs up on this video are through the roof.

[@pinkdispatcher]

That's just awesome. Thanks a lot; it all doesn't sound very complicated when you explain it, but I guess a lot of engineering has gone into this 1980's beast, I particularly imagine the electron beam focusing to be a crucial parameter.

[@nixietubes]

Absolutely beautiful piece of equipment, looks like so much fun to play with

[@seanmcmunn88]

Those images are fantastic, and the processing involved is ingenious!

[@skaterzero807]

Enjoyed your vids for a while now, glad I can support and buy a shirt. I love how you teach something cool in an understandable way while also doing some pretty awesome things! It is inspiring as a maker to learn things that seem like they should be best left to the pros.

[@AppliedScience]

Thanks! I really appreciate it. It's often a good idea to learn from people that you suspect know what they are doing, however I'd be careful about assuming there is anything "best left to the pros." No one is good at doing anything when they are born -- it simply takes dedication and interest to develop skills as well as the courage to try something and fail a bunch of times.

[@skaterzero807]

Applied Science Thanks! Also, if you don't mind me asking, how difficult is it to get a job at a place like Google[x]? I am pursuing my PhD at Georgia Tech and want to have a similar job where you are given projects/problems to solve but am worried I should have gone into industry and gotten more hands-on experience as a research engineer or something more applicable. On the other hand, does a doctorate degree help when applying to such a job? Thanks again for your response.

[@AppliedScience]

skaterzero807 As you might imagine, [x] is pretty selective. However, our publicly announced projects show that there is a need for specialists. I'm not directly involved with recruiting, however in general, I'd say that candidates who have a good track record of independent contribution and strong interest in their field are most successful.

[@Adamthehoff]

This is such an excellent video. I have been spoiled by new SEMs and it is so nice to see how one works without advanced computer technology. I can't wait to see more videos about your instrument!

[@Adam_Outlaw]

I see a money making opportunity... sell EM images made from items mailed to you:)

[@NickMoore]

Ultra long exposures, that's an awesome solution! Could you use the same trick as astro-photographers by stacking many frames to get even finer detail?

[@AppliedScience]

That's an interesting idea. I think it would probably work really well. I'm imagining an image that progressively improves in realtime as more frames are acquired. Then, it resets when focus or pan is changed on the SEM. Cool!

[@ezcreations777]

Applied Science You should make a video of you doing that Maybe even take user suggestions for things they wanna see you put under the microscope

[@SuperDachshund]

Applied Science I'd love it if you'd do a piece on "Stack and Stitch" photography. Using a regular telescope you could get some fantastic pictures of the moon with super high resolution!

[@skepticmoderate5790]

I believe they do.

[@Rotem_S]

Applied Science why resets? just put the original image as part of the new screen

[@toki4139]

Im impressed by the technique ! The way you use the oscilloscope...so cool

[@alggu1]

So, you just built an electron microscope ON YOUR OWN. THAT IS AWESOME!

[@AddyKanhere]

Amazing!! Seeing something like this just gives any engineer joy. Please do more videos on the complete physics behind the working.

[@Keith_Ward]

Awesome work here Ben. And considerable kudos to Mr. Anderson for recognizing that equipment like this needs a new home. Unbelievable that something like this could end up in the trash, but it happens every day and usually by big corporations and other wasteful institutions.

[@azyfloof]

So using the camera to collect the final image would be like using a camera with a slow shutter speed for capturing star trails or other low light phenomena. As for the beam focusing problem, I now know exactly why I was having trouble with beam focusing when I was experimenting with CRTs many years ago. Had no idea it was because the electrons were repelling each other! I came for the science, but stayed for the knowledge. Ben, a thousand hats off to you :D

[@commiebobo]

Where has this channel been my whole life?

[@zetacon4]

Wow! Very impressive work. Love the images you captured. I miss using the SEM that we had available in 1980 at Andrews University. I was working in the electronics lab on an OP amp circuit assignment. The OpAmp failed. So, I kept it and wanted to find out why it failed. I took the metal cap off the base, put it in the SEM and found that a small aluminum trace between to parts of the circuit had suffered a current overload. Knowing that I had not caused that during my use of the circuit, I suspected that there was a defect in the trace from the manufacture of the part. Over time, as current passed through the trace, it weakened until it failed. The metal actually pooled up into a bubble, causing an open-circuit condition. As the part had worked fine for me until it failed, I wanted proof of the cause. Now I was certain I had not caused the failure. The images were so clear and in focus, I had no doubt about the cause of the failure.

[@snower13]

Thanks for taking the time and sharing your experiments and results; but most importantly, your knowledge.

[@martinstrydom736]

Your versatility is like the modern day Tesla! I dig how just do stuff keep on inspiring young minds Ben!

[@UberAlphaSirus]

Wow, Props to the guy who donated it. And massive thanks for your upload. 12 minutes educated the life out of me on electron microscopes.

[@madeinuk68]

I don't understand the tech one little bit.But the images are amazing.The micro world totally fascinates me.I would love to see the internal workings of a fly.I mean just imagine seeing the heart of one,assuming of course they have one,they may have more than one.Wow! What a wonderful machine.

[@BlackPhanth0ms]

Even though I will probably never replicate this, I still learned a ton from your video. Really interesting, I would love to see more on this. Thanks!

[@aphexteknol]

Man, what I wouldn't give to sit around and play with a real SEM. Like most people, I've had various microscopes all my life from cheap-o Tascos with the ubiquitous prepared slides all the way to my current one thats actually has nice german made lenses, but I've always wondered how much detail I'm missing from being able to use a real scanning electron microscope. Thanks for the videos Mr. Krasnow, I love them all.

[@bam1314]

When I think I am intelligent all I have to do is watch your videos to bring me back to earth. It is kind of like watching Jeapardy and wondering how do they know that? Thanks for the hard work and expenses. You are a true genius.

[@johnwilson3918]

Great video. My thoughts changed from 'Wow! What an amazing microscope!' - then to - 'Wow! What an amazing oscilloscope!' - finally to - 'Wow! What amazing pictures!'... Wow!

[@Jbizzyboi]

finally a way to support Ben, totally buying a shirt!

[@motherjoon]

As a second year engineer, I didnt get most of the oscilloscope terminology but very interesting video. Inspired me.

[@sqol]

Your videos always impress, Ben, but this one is quite special- very exciting to see how this reasonably simple method improves the visual quality by so much.

[@jelonek55]

What you present in your videos is just amazing. Beautifill and engaging engineering. Greetings from Poland!

[@satanshollowd]

I cannot express how impressed I am by this

[@4dirt2racer0]

I absolute love this video.. N the last one, n the one before that.. O and the one before that.....

[@BlackEpyon]

You're oscilloscope puts my old clunker to shame...

[@chemicalbombgang]

man you're amazing !!!!! Im always soo desperate to see your ideas that you use !!! keep up the great work BEN !!!

[@nomadben]

This is absolutely incredible.

[@b00bsism]

Amazing! I have watched quite a few of your videos now and I always ask myself at the end of each one "How does he know all this stuff". Just amazing.

[@SlickFungi420]

Man, you're awesome.. when I subscribed to your channel; long before the rename, I knew your channel had potential.. but I never anticipated all the amazing things you've done.. especially not recording digital images from an analog SEM the way you did.. you kick-ass!

[@longshot789]

Wow, what an incredible job you've done.

[@RimstarOrg]

Very cool images. And I thought I ran out of drool the last time you showed us tricks with this scope. :)

[@DaveYeagly]

Your genius continues to blow me away! Absolutely amazing!

[@mikeselectricstuff]

How about a timelapse of something getting degraded by the electron beam. BTW how long does it take to pump down? Does it pump the whole chamber or is there an airlock for the sample chamber?

[@AppliedScience]

You may not need a timelapse to see damage caused by the beam. I was looking at strands of hair, and at 25KV with a large spot size, the beam will start to "bubble" the hair. It creates a fairly large blister in 5-10 seconds. Yikes. This SEM pumps the whole column down as one unit, and doesn't have an airlock or nitrogen purge. It only takes about 10 minutes to change samples, though. It also has two separate stages for small and large samples, which can be manipulated separately, and a few unused blank plates (I'll add electrical feedthroughs).

[@williamhayden7711]

Applied Science would love to see some video of this and whatever else fancies you. Electron microscopes are just fascinating. I could look at anything under one.

[@Alexander-ri1bp]

Applied Science Hello Ben, are you afraind of X-ray radiation when the electrons are de-accelerated? I mean, the glass bell do not protect you very well.

[@AppliedScience]

Alexander A. The DIY SEM used acceleration voltages of under 10KV, and X-rays generated by these relatively low speed electrons will be stopped by a very thin layer of glass, so the bell jar is more than sufficient. Black and White televisions did not have lead shielding for this reason. The JEOL uses acceleration voltages up to 25KV, but the chamber is relatively thick stainless steel, and this sufficient to stop the X-rays generated by the beam, which is already extremely small (50uA emission current).

[@Flumphinator]

This left me speechless. You're a wizard.

[@Magnussen92]

I am amazed by your level of information and understanding. I'm almost lost for words after this video and my only explanation is that you must be Einstens second coming! I have no idea what so ever what you did or how you did it. Basically all I understood was the word "shipping" XD That being said it was still very enjoyable to watch, just as all you other videos! It's 04:28 here in Norway at the moment because I've just been up watching video after video from you!

[@angryyoungman4389]

Bjørnar Magnussen That's a big respect

[@Matt-uf2nc]

you never cease to amaze with your projects. keep it up!

[@ThingEngineer]

I really appreciate the information and experiences you share in your videos! This one really impressed me and I can't wait to see how having a real SEM enhances your future exhibitions.

[@aphexteknol]

Also I'm very surprised at the images you managed to capture without having to plate the specimens in gold like most SEM operators have to do. The fly image especially is just amazing for what it is. I wonder what difference gold plating would do if you were to rescan the fly now that we know it works well enough without it? Would you get any better resolution/detail at all do you think?

[@AppliedScience]

Coating with metal will definitely help -- especially for higher magnifications, which require smaller spot sizes, which really need as much signal as possible. Most labs that have a SEM also have a dedicated sputter coater, so it's easy for them to always coat specimens, and write it into their protocol. My sputter coater is working, but was recently moved, and hasn't been setup. I tried scanning an uncoated insect and was surprised how well it worked. You'll never see a proper SEM lab do this since they already have a full complement of tools. Sometimes it's good to just try something and see what you get! In general though, coating with metal will help the image quality in every way.

[@das250250]

Once again ... brilliant stuff Ben .. Would love to see more images of interesting things

[@mohamedqasem]

Amazing!! I can't believe that you were able to use an oscope to get the image.

[@ankitk5530]

Wow! good to see those pictures. You are genius. Wish I had the level of knowledge you have.

[@freeelectron8261]

Really amazing work you are doing! Beautiful detailed images at the low scan rate. I really appreciate that you take the time to communicate challenging topics in a clear and concise way that allows the non specialist to get a handle on these interesting machines. Subscribed! Might even get the tee.

[@gdfr7]

You're absolutely genius. Loved this project

[@seanramirez4971]

amazing! i never would have thought to take the output into matlab to render the images. Great job!

[@dizzious]

Wow! This is a truly amazing project. An electron microscope has got to be one of the holy grails of DIY :D

[@CookingWithCows]

man if I had my own electron microscope I'd sit there the whole day taking images of all the things that I find and never get bored of it, haha

[@deserty7883]

You are the coolest person ever! I do not care what anyone else says, you make everything amazing! Please keep them amazing videos coming! I eagerly await them!

[@Putrycz]

My new favorite channel.

[@blackhatvisions]

wait wtf. i thought you captured an electron from the title. i was so hyped . dang it

[@Chaoddity]

That is a gorgeous piece of equipment.

[@johnfranks]

With only 5V peek to peek, a relatively slow sample rate, and the low resolution ADC of the scope; would a 24bit/96KHz sound card not be better suited as a capture device?

[@puddingpimp]

If there is significant high frequency noise in the signal (and there is), then although the scope is only 8-bit, the effective bits after digital low pass filtering is much higher (as a rough rule, add a bit for each halving of the bandwidth). The best screens (DICOM monochrome LCDs, $$$) are only 12 bit output, and most screens are only 8 bit (though you can get cool temporal dithering software to extend this), so anything over 12 or 14 bits is overkill. Still it might be the cheapest option to use a 24/96 USB soundcard if you need a 48kHz pass band. Anyway, the proof is in the output; the SEM of that MEMS device is ultra-sharp and the SEM of the fly is well defined and amazing beautiful micrography. I would use something else, not for the quality, but because I believe every tool in my lab should be accessible and ready to use, and I couldn't afford to have an expensive scope setup like that permanently.

[@RayDrouillard]

Capturing the signal with an oscilloscope is rather clever. I like the way that you are thinking outside the box. Since I have been playing with SDR (Software Defined Radio,) it occurred to me that you ought to be able to use one of those twenty dollar SDR modules to grab the signal and send it straight to your computer.

[@brentfisher902]

All you need to do is solder a fine solid copper wire to one of the pins on the RTL-SDR chip to enable direct sampling, then record with 'rtl-sdr' program in direct-sampling mode by changing one line in the C code. The negative is just the negative power terminal of the USB plug. Also once you did all that you now have a tool that can create a rewindable record of the AM radio stations...THE WHOLE THING, that's right! You can record everything the antenna hears and if you got done listening to one interesting station, you can REWIND THE RADIO and go back and hear what another station was broadcasting AT THE SAME TIME. And a BD-R 25GB single layer disc will hold 1 hour and 25 minutes worth of it. All you do is tune to 1.2 Megahertz and run the sampling rate a 2.4 Megasamples per second.

[@EnergyWell]

That is the coolest thing I have ever heard anyone ever say. "Check out my scanning electron microscope collection."

[@farvision]

A cool thing you can do is look at a live electronic chip surface. The charge of the surface makes the EM signal brighter or darker, so you can directly see the circuit running!

[@lorenzovanhethul1355]

Unfortunately, you won't be able to see that on a semiconductor. You are able to see that on the pins of the chip. He already tried it.

[@farvision]

Why is that? Is it because the semiconductor is covered or some physics reason?

[@lorenzovanhethul1355]

farvision semiconductors are very small, those traces are incredibly small, but the main reason is because there is a plastic protection film over the die. So you have to remove that clear plastic film in order to see them light up or get darker with the SEM. Chances are soooooo little that the IC will still work. But its certainly possible without breaking the IC. The electron beam interferes with the protection film. The protection film is applied to protect the die from damage when it gets capped by the mfr. But main reasons: traces are to thin, and the protection layer which interferes with the SEM. But i'm sure you can see the traces light up or get darker when those things are done. But its very hard en almost invisible. I would love to see a live computer CPU under the SEM, that would be awesome especially if you can see what its doing.

[@sebastian.salmhofer]

Wow, those images are awesome quality.

[@kadenzxc]

You're a tech ninja man. Really cool work.

[@agentwaldheim5274]

Love your channel because of the wide field of science you present that is very technical, yet 98% understandable to us that do not have a science background, thank you very much.........One more curious note: the ads KZbin puts on your videos, like the one here about using an oscilloscope for microscopy, the ads are for a manufacturer of microscopy instruments, very interesting note..!

[@pcrengnr1]

Applied Science, Great job of the video and the technique to acquire a better S/N and more resolution. Since the scan rate is so slow you might consider using the sound card input for the DAQ. As you the sound card has at least 16 bits and some have 24. So with an appropriate scan rate and that resolution your pics should look even better. Thx again for the video and the insight.

[@razzintown]

That is jaw dropping amazing

[@attaoveisi8219]

I appreciate your efforts in applied science. Salut! I would be very happy to have such an instrument in my Lab.

[@mitroer]

Really amazing video. I like the good insight into tech I don´t have access to. The use of a scope as a data sampling device is inspiring. And finally, amazing images!

[@FranLab]

Now I want a SEM Ben! (I have the right Polaroid camera to keep it period authentic too..... :-)

[@sebastianschmidt566]

i would one too

[@orangedac]

You should marry Ben. Your offspring could be the next Nicola Tesla with all that electronics knowledge concentrated in the genes.

[@sebastianschmidt566]

orangedac or he would be the next Dr Frankenstein :-P

[@jcims]

Cheers to Mr. Anderson for seeing the opportunity and to you for taking advantage of it. The scope gets a new lease on life in education! Looks like a high quality piece of equipment (especially after what you said regarding the shipping damage) Do you think you could use an audio card as a poor man's scope (with some conditioning of the input of course) to record these images? The MDO is lovely at it, of course, but it's not exactly a low cost item, lol. I believe the Wolfson card for the Raspberry Pi is ~$35 and the ADC seems to be able to record at 192ksps.

[@AppliedScience]

Yes, when I started making this video, I intended to use a USB audio adapter as the capture device. Mine is a cheapy model, and only does 44KHz, so it would work for the SEM's 60-second scan, but would not have enough temporal resolution for the 10-second scan. The audio device is 16-bit as opposed to the Tek's 8-bit, so there would be an increase in dynamic range. Also, all audio adapters will need to have their input coupling capacitor bypassed. I did this on mine, and it worked well. However, some models include digital high-pass filters implemented in the ADC itself, and these are essentially impossible to bypass (like the ones in the Handy H4n). The DC input range on my adapter was something like 2-3 volts, so the signal from the SEM would need to scaled and offset -- not too difficult, though. Other alternatives are the LabJack, Measurement Computing, and NI USB-600x models.

[@jcims]

Very cool! And thank you for the short list of alternatives at the end, couple of things in there look like they will be useful! Also, ordered shirt. Paypal via Chrome was a bit wonky in case you hear anything. IE was fine (go figure, lol)

[@puddingpimp]

jcims You can use a USB audio card, but you need to remove any DC decoupling caps from the interface, and you don't get very good control on the actual sampling bandwidth. If you want to eliminate (or enhance) super-nyquist aliases, you should use a sample and hold ADC. You can get plenty of cheap uCs or FPGA boards with 250ksps ~ 2MSPS sample and hold ADCs, and it's kind of trivial to build an opamp circuit to bias, filter and amplify the input signal. If I had an SEM to play with, I would attach it to my Terasic C5G board with HDMI, so the picture shows up on the screen as it captures. It has a 500ksps 12-bit ADC which is surely fast enough for the task at hand. Unfortunately while FPGA boards are cheap and widely available, SEMs are expensive and rarely sold used in my neck of the woods. If I was to build an instrument it would be a scanning confocal microscope, rather than an SEM, but that's my preference, not a recommendation for others.

[@brentfisher902]

If you want to send a very slowly changing signal near DC frequencies, you can set a 555 timer as a square wave oscillator at a frequency that the sound card can hear then hook the signal to a pin on the chip which will modulate the frequency, then you can use an interpolated zero-crossing demodulator in a C program to recover the voltage trend.

[@madriiax]

Sweet toy, can't wait to see what comes of it!

[@StephenTack]

Knowledge, inspiration, and tee-shirt acquired!

[@paulgaier4525]

You might have the best job in the world. This was fun and extremely informative. Love the way you married old tech with a modern o'scope. I've been using scopes since the 80s but I've never heard of a mixed domain type, but it makes sense. I'll be looking it up. Thanks for posting. Subscribing.

[@Firecul]

This is very impressive, especially when it is able to get the blood cells.