<_whitenotifier-f>
[starshipraider] azonenberg pushed 1 commit to master [+0/-0/±12] https://git.io/JfxOg
<_whitenotifier-f>
[starshipraider] azonenberg 9617d01 - Continued schematic review. Finished verifying pinouts. Assigned lots more footprints.
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<_whitenotifier-f>
[starshipraider] azonenberg pushed 1 commit to master [+0/-0/±3] https://git.io/Jfx0L
<_whitenotifier-f>
[starshipraider] azonenberg 998540e - Continued assigning footprints. Renamed some ferrites from L* to FB* refdes. Renamed a test point from J* to TP*.
<azonenberg>
progress, now about 60% done assigning footprints
<_whitenotifier-f>
[starshipraider] azonenberg pushed 1 commit to master [+0/-0/±4] https://git.io/JfxE8
<_whitenotifier-f>
[starshipraider] azonenberg d6ef279 - Continued assigning footprints. Done with everything up to and not including resistors.
<_whitenotifier-f>
[starshipraider] azonenberg pushed 1 commit to master [+0/-0/±18] https://git.io/Jfxz1
<_whitenotifier-f>
[starshipraider] azonenberg adc3b1b - Assigned footprints for all resistors
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<katharina>
i forgot how annoying it is to implement sum types in C++ without inheritance
<azonenberg>
katharina: sum types?
<katharina>
a sum type T := A + B has at any time either a value of type A or a value of type B, not both, and not none of them
<katharina>
std::variant<Ts...> in C++17
<azonenberg>
Hmm
<azonenberg>
What C++ version is supported in ubuntu 18.04's gcc?
<azonenberg>
or debian stable
<azonenberg>
or whatever mingw you're using
<azonenberg>
any features supported on all of those platforms are OK to use, we've kept the project at C++ 11 mostly because there was no reason to use anything higher
<azonenberg>
If you've got a good reason, and it builds on all of our target platforms, i have no objection to moving up to 17
<katharina>
C++17 isnt supported by Gcc 7.x.x which is shipped in Ubuntu 18.04
<katharina>
but its fine, i did implement my own sum type already
<katharina>
its a few hours of work up front, but it does carry many benefits, such as not having to store your sum types on the heap and use pointers-to-base-class (if you go the inheritance route)
<katharina>
azonenberg: Would you be alright with me refactoring some of the file system code in glscopeclient later on?
<katharina>
I find myself using platform-dependant things like "is this a real file?" a lot, maybe its time to make a central implementation the whole project uses
<azonenberg>
Makes sense. And yes, I think that would make sense
<azonenberg>
i mean that's already done in heavy libraries like boost but i really want to avoid pulling that in
<azonenberg>
Make a ticket for that and assign it to yourself
<azonenberg>
for now it can live in libscopehal but i think longer term it might make sense to move to xptools if we find it's generic enough it might be useful in other projects
<katharina>
yea i thought about boost for a second but i really dislike how large it is
<katharina>
shall i make the ticket in libscopehal?
<azonenberg>
Yes
<azonenberg>
actually wait
<azonenberg>
Put it in xptools to start. that's where it really belongs
<azonenberg>
let me add you to the project
<azonenberg>
xptools is basically my lightweight cross platform abstraction library for things that libstdc++ doesn't already handle like threading and mutexes
<azonenberg>
so anything that's portability related but not GUI or specific to oscilloscope stuff should go there
<azonenberg>
Just invited you to xptools
<azonenberg>
Make the ticket and wrappers in there
<_whitenotifier-f>
[starshipraider] azonenberg pushed 2 commits to master [+0/-0/±25] https://git.io/JfxKF
<_whitenotifier-f>
[starshipraider] azonenberg 268626f - Began assigning IC footprints
<_whitenotifier-f>
[starshipraider] azonenberg 3b2dfd3 - Added footprints for most ICs other than DC-DC modules
<azonenberg>
i still have to do most of the DC-DC's and assign a few STEP models to things like esd diodes and the big caps
<azonenberg>
this is going to be one heck of a layout
<katharina>
did you have to create the 3D models for the exotic parts yourself?
<azonenberg>
i did the kicad footprints but all of the 3d models were vendor step models
<azonenberg>
connector vendors are generally pretty good about providing mechanical models
<azonenberg>
the BGAs in some cases are just generic bga footprints scaled to the right size
<azonenberg>
so wrong ball count
<azonenberg>
those are just for show, the connector footprints are important because i use them for verifying clearance etc
<azonenberg>
and sanity checking that all of the mounting holes are in the right spot
<azonenberg>
Not yet in the layout: six dc-dc modules, a crystal, and an OCXO
<katharina>
what kind of connector is J18? Never seen those before
<azonenberg>
once all of those are done i can continue the schematic review, which is probably going to take most of the rest of the week
<azonenberg>
Those are SFF-8087 aka mini SAS connectors. Normally used on server backplanes
<azonenberg>
they carry four lanes of SAS or SATA on one connector
<azonenberg>
or, in my case, eight LVDS lanes from a logic analyzer pod
<katharina>
ah, interesting reuse of the connector :)
<katharina>
are those expensive?
<azonenberg>
$7.41 each. So not CHEAP, but compared to the $10.66 SMA connectors or the $386 FPGA, not a huge portion of the overall BOM
<azonenberg>
Although the twelve of them do cost $88.96 combined
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<katharina>
azonenberg: do you want the config file to be in ~/.config/scopehal or ~/.config/glscopeclient ?
<azonenberg>
hmm, good call. I guess glscopeclient makes more sense for UI stuff
<azonenberg>
but ~/.config/scopehal makes more sense for things like plugins that are usable in headless/API mode
<azonenberg>
Since i intend for libscopehal to be usable in automated testing environments without using glscopeclient, so we need to have plugins not depend on the UI
<azonenberg>
We may eventually have preferences for the library, or specific filters, at some point? if so, those will go in ~/.config/scopehal.
<katharina>
sure. I would also say that plugins still go to ~/.local/share/scopehal
<katharina>
since you say, headless use
<azonenberg>
Yeah
<azonenberg>
Just make sure all of these directories are documented somewhere
<katharina>
yea
<azonenberg>
We have a huge amount of catch-up to do in the docs, so i want to make sure all major new features, or changed features, get documented
<azonenberg>
and then as time permits go back and document existing stuff
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<katharina>
azonenberg: Apparently, its considered "best practice" to react to the GTKMM "hide" signal instead of "destroy" if you want to do cleanup
<katharina>
what are you opinions on this, if any?
<azonenberg>
katharina: I haven't done any research into this either way. But I think 'destroy' is permanent while 'hide' can be called more than once
<azonenberg>
if it's a dialog you show when needed then close, then bring back
<azonenberg>
so it would make sense to do per-run cleanup in hide
<katharina>
got it. lots of conflicting information. ill stick with the existing destroy handler you added until we notice any problems with this
<azonenberg>
what is this for, the app or the prefs dialog?
<azonenberg>
in the case of the app, note that we have a function called i think ClearSession() that is used to reset an OscilloscopeWindow when loading a save file or otherwise clearing all active state
<azonenberg>
this is also called during shutdown for cleanup
<_whitenotifier-f>
[scopehal-apps] nshcat opened pull request #120: Basic preference system infrastructure - https://git.io/Jfx14
<_whitenotifier-f>
[scopehal-apps] nshcat created branch preferences-gui - https://git.io/JvExD
<_whitenotifier-f>
[starshipraider] azonenberg pushed 1 commit to master [+0/-0/±6] https://git.io/JfxHD
<_whitenotifier-f>
[starshipraider] azonenberg 2b3ea40 - Added footprints for everything but LCD
<katharina>
azonenberg: https://i.imgur.com/iPRx3jw.png have you seen this theme issue before? There is a number in the "test real" field, but the text is black so you cant see it
<azonenberg>
Interesting. Are you familiar with how to use the gtkmm inspector?
<katharina>
i did not manage to get to the office yet, so you checking if it works with your scope will give us valuable info
<oskar>
No problem at all, I'm glad to be able to help.
<oskar>
Run & Stop works
<katharina>
would you be so kind to send me a screenshot of the GUI? I want to make sure everything looks ok
<katharina>
ofc only if thats comfortable for you
<oskar>
Yeah sure I'll PM you it
<oskar>
Sent
<katharina>
awesome, thanks!
<oskar>
No problem
<electronic_eel>
azonenberg: about leds for the MAXWELL host ports - I don't think they are necessary. we got the lcds on the pods, so no help for identifying the ports.
<electronic_eel>
if a la pod should have connection problems, I don't think a led is enough. then you want current drawn, uart status and so on, you can't display that with just a led
<electronic_eel>
so I don't see a use case where a led would help
<oskar>
Katharina did you get my private message? I don't know if I did it right, very new to IRC and weechat
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<azonenberg>
oskar: you're able to pull waveforms from your scope?
<azonenberg>
electronic_eel: that was my thoguht. we have the ina233s
<azonenberg>
Katharina: re your pull requests you submitted
<azonenberg>
should #122 be merged before 121, or are they order independent?
<azonenberg>
i havent actually looked at the code yet, wondering which to touch first
<oskar>
Doesn't seem like I am able to, but I am going to try some more later
<katharina>
oskar: yes i did, it looks fine
<oskar>
Great, thanks!
<katharina>
azonenberg: 121 is just an issue for the ui-dev branch. Id like the PR 122 to be merged first. It contains a barebones impl of the dialog with logic in place. When that is okay and landed, ill make it pretty
<azonenberg>
oskar: so you can start and stop the scope, but it doesn't display any waveforms?
<oskar>
Correct, although I may just be using it wrong
<azonenberg>
Try launching the executable with the --debug argument, and upload the console output to a pastebin or something
<oskar>
Will do
<azonenberg>
also what was the exact make/model you were testing on? i know its a keysight but not specifically
<oskar>
MSOX2024A
<azonenberg>
(paging miek since he was working on the agilent driver)
<azonenberg>
Very likely something is different about your scope vs the ones we've worked on in the past
<oskar>
or I may be using it wrong, I'll try the --debug now
<azonenberg>
if the offline mode works to display waveforms from save files, and you can send commands to the scope (start/stop), i think all of the pieces should be working
<oskar>
Yep I could view the test USB waveform included
<katharina>
oskar: did you try the USB dataset i shipped in the archive?
<azonenberg>
the most likely explanation is the driver sending a command that's not valid for your hardware and/or not correctly interpreting a reply
<oskar>
Ye
<azonenberg>
meaning your scope is somehow different from the agilent ones we've tried in the past
<azonenberg>
Not entirely unexpected
<oskar>
The software turns on all 4 channels of my scope and turns on single capture mode on start so some commands are def working
<azonenberg>
oskar: more importantly that means that at least the transmit side of the communications link is working
<azonenberg>
basically, the set of things that are known to work on your scope+computer system encompasses almost everything but the driver itself
<azonenberg>
Hence why I blame the driver
<oskar>
Yeah true, I can turn on and off channels ok, but no waveform.
<miek>
does it have anything to trigger on?
<azonenberg>
(ah, good point)
<oskar>
No it's a constant 3.3 V DC signal, so maybe that could be why?
<azonenberg>
Yeah. glscopeclient does not currently support auto trigger mode
<azonenberg>
or "force trigger"
<oskar>
Ohh
<azonenberg>
meaning you have to have a valid level to trigger on for anything to happen
<oskar>
Do I set that up on my scope as normal or is it in software?
<azonenberg>
on one of the channels there should be a little triangle on the Y axis
<miek>
scope, probably. (i can't remember how much of that stuff is implemented in the software right now)
<azonenberg>
you can drag that to set the trigger level if the driver supports it
<azonenberg>
but the agilent/keysight driver is pretty new and that function may not work yet
<oskar>
It does
<oskar>
I see it moving on the scope too
<azonenberg>
Ok
<miek>
ooh, neat
<azonenberg>
so in that case hook up a probe to a signal that actually has some edges on it and see what happens
<oskar>
I'll try and find one ahah
<miek>
probe comp output on the front?
<oskar>
Oh I got something!
<katharina>
awesome!
<oskar>
I tapped the probe on the battery connector to try and get a rising edge and it did
<azonenberg>
perfect. so as far as you can see it's working?
<miek>
nice!
<oskar>
Yeah I'd assume so, but I know very little about the software, I'll try a demo signal on the scope
<azonenberg>
oskar: have you read the manual yet? do you even know where to find it?
<oskar>
Yeah I got it, I'll give it a read so I don't mistake my lack of knowledge for issues
<azonenberg>
OK. also if you run into a problem with something that's not in the manual, let us know
<azonenberg>
there are significant gaps
<azonenberg>
miek: can you add his msox to the docs as working? and make a new section for keysight if there isn't one already
<azonenberg>
we'll keep the driver called "agilent" for now but i want models listed under the brand they're sold under
<azonenberg>
so HP for really old, agilent for middle, keysight for newer
<azonenberg>
double list if a model spanned the spinoff
<azonenberg>
since some may be labeled both ways
<monochroma>
there is a lot of stuff that keysight still sells that was originally agilent
<azonenberg>
monochroma: yes and thats why i want them double listed
<azonenberg>
people arent going to know to look for those models under agilent
<azonenberg>
especially newer fresh out of school engineers who dont know that keysight/agilent/hp are one lineage
<monochroma>
then they should go back and ask for a better degree :< ;)
<azonenberg>
So if it says keysight on the front of the unit i want it listed under keysight in the manual, and if that same model was sold with agilent branding put it there too
<azonenberg>
Lol
<oskar>
By the way, is the Run / Single supposed to be very quickly triggered on the scope? I'm seeing the single button flashing really quick on the scope when probing a sine wave
<azonenberg>
I'm not making two categories for lecroy pre/post teledyne because if you search lecroy you still end up in the right spot
<azonenberg>
oskar: Yes. I don't actually use the "normal" trigger mode
<azonenberg>
because this can cause problems when you download data from one channel then the next channel comes from another trigger
<azonenberg>
so i have to arm the trigger, collect a waveform, pull everything i need from it, then re-arm for another capture
<azonenberg>
it's a limitation of current remoting APIs
<azonenberg>
as opposed to the ones we're designing for our custom hardware where you subscribe to notifications from the scope then it pushes you waveforms every trigger as fast as it can
<oskar>
Ah that's cool, so that's what the insane logic analyzer you are making is for?
<azonenberg>
and it sends you the data for every channel you want, because you told the scope what channels you wanted to see
<azonenberg>
It's one of several projects that are kinda the parallel arm of this project
<oskar>
Very cool
<azonenberg>
glscopeclient is intended to be a unified UI that works with both our gear and third party stuff
<azonenberg>
basically if it acquires a time series of electrical data on some kind of trigger, it's fair game :p
<azonenberg>
even frequency domain signals are in scope, the architecture would fit just fine with a specan instead of a scope or la
<oskar>
Awesome
<azonenberg>
although to date nobody has implemented support for any
<azonenberg>
but all signals are strongly typed and the UI doesn't care if a frequency domain signal is the output of a fft filter or the native datatype of an instrument channel
<Degi>
Ugh, people calling things "open-soure hardware" where there are no kicad files published (only the schematics) and the used ICs are some broadcom stuff you'll never get...
<azonenberg>
But yes, MAXWELL is one of the two actively developed hardware projects from the group
<Degi>
Its pretty nice that for our devices you can get all ICs off of digikey or mouser or so
<azonenberg>
the other is BLONDEL which is an oscilloscope roughly in the ds1000z class
<azonenberg>
eight channels split into two groups of four
<oskar>
That's unfortunate that some people do that, I didn't know
<azonenberg>
each group is 1 Gsps 8 bit or 500 Msps 12 bit, and you can split that sample rate across any one, two, or all four channels
<azonenberg>
this is completely independent for each group so you can have one group in 1ch 12 bit 500 Msps mode and the other in 4ch 8bit 250msp mode
<Degi>
Yay
<oskar>
On windows too which is good
<azonenberg>
oskar: awesome, and i was about to ask
<Degi>
Oh neat
<azonenberg>
i see two missing toolbar icons
<Degi>
I have that too on linux
<azonenberg>
but that's a known issue already being addressed, some gtk themes dont have all of the icons i use
<azonenberg>
i'm under contract with a professional illustration studio to draw new toolbar icons for everything that are specific to our use case rather than using generic media player icons etc
<azonenberg>
They just haven't delivered yet
<oskar>
Ah
<oskar>
This UI is already better than the keysight software gumbo rubbish
<azonenberg>
Lol
<oskar>
Well Keysight's isn't bad, I guess it's just very expensive, and I'm a student, so...
<azonenberg>
Lol. if you've used lecroy scopes it's fairly heavily inspired by MAUI, but optimized for mouse driven operation instead of touchscreen
<azonenberg>
i havent used any recent keysight gear so cant comment and the last tek i used had a floppy drive
<oskar>
Wow
<oskar>
What scope do you use?
<Degi>
The TEK I have here doesnt even have that
<azonenberg>
oskar: I have a WaveRunner 8104-MS and a HDO9204
<_whitenotifier-f>
[scopehal-docs] miek opened pull request #12: Document more Agilent/Keysight device support. - https://git.io/Jfpti
<azonenberg>
I've negotiated a deal to sell the 8104 and trade it in towards a discount on a WaveRunner 8404M-MS but haven't come up with the cash to finalize the deal yet
<azonenberg>
But yes, my goal is to be better than the vendor software :P
<oskar>
Sounds cool, the WaveRunner is a beautiful scope
<Degi>
Why do these rly pricy scopes only have 128 Mpts
<azonenberg>
oskar: anyway, right now BLONDEL has a single channel prototype working in hardware sitting on the lab bench next to me
<azonenberg>
I need to characterize it more completely, and there's a few bugs that we had to fix with bodgewires on the prototype
<azonenberg>
then we need to figure out some other details like the active probe interface
<azonenberg>
before we can build the full instrment
<Degi>
Hm yes
<azonenberg>
(anybody heard from corgi lately?)
<azonenberg>
BLONDEL will also have two 8-bit logic pod connectors, the same as MAXWELL
<azonenberg>
except two instead of twelve :p
<Degi>
Tbh I'd be interested in frequency response above 100 MHz, especially around 650 heh
<azonenberg>
MAXWELL is a pure play LA
<Degi>
Hmh they dont seem to be online
<oskar>
Are you planning on designing a low cost LA?
<Degi>
"low cost"
<Degi>
Nah its gonna have 80 channels
<oskar>
I guess that's like "how long is a piece of string"
<azonenberg>
oskar: Possibly. MAXWELL is designed to fill a specific requirement Pretzel4Ever had
<Degi>
The scope will have a LA too
<oskar>
The requirement of that many channels? Must be doing some insane stuff
<azonenberg>
I guess if you wanted a cheap LA, you could build a BLONDEL and not populate the analog cards
<Degi>
Yeah that'd work
<Degi>
Considering that the boards cost like 200 or 300 $ each heh
<oskar>
How much would that be?
<azonenberg>
BLONDEL is going to consist of a main board with the MCU /FPGA/RAM, a little adapter for the LA inputs and external triggers without much circuitry, just some connectors
<azonenberg>
then the two 4-channel analog boards
<oskar>
Oh, that's not too bad price wise
<azonenberg>
oskar: we'll let you know when we're done designing it
<azonenberg>
degi was talking about an estimate for one four channel analog card
<azonenberg>
Not for a full system
<Degi>
Yes
<oskar>
Oh
<Degi>
I mean the rest is probably gonna be another 2-300
<azonenberg>
i estimate a full BLONDEL system in digikey qty 1 pricing will be on the order of 1-1.5 kUSD
<azonenberg>
hopefully below 1K in higher volume
<Degi>
I wanna do a version with only 1 card sometime, which will be somewhat cheaper (maybe even a HMCAD1511 variant? That'd save 50 bucks. 1 channel? Would save a lot too)
<azonenberg>
we could always DNP all but one input on the 4ch board
<azonenberg>
and the 1511 is pin compatible
<azonenberg>
we could also make a less heavyweight, interface compatible host board without the DDR and 10GbE
<azonenberg>
just a small fpga and block ram and 1GbE
<azonenberg>
then play lego mixing and matching them
<azonenberg>
I'm not against making low cost gear but my interest is on the high end
<azonenberg>
I'm not trying to make OSH competition for rigol
<azonenberg>
I want OSH competition for lecroy and keysight
<Degi>
Hmh yes, like a 400 MHz 1 channel cheap-ish version would be nice.
<azonenberg>
BLONDEL is "too slow" for my needs, i'm only making it as a learning experience before moving up to higher end
<Degi>
Hmh yes rigol is probably unbeatable
<oskar>
That would be very nice
<azonenberg>
trying to make my mistakes and learn analog stuff on the 100 MHz scope and not on the scope with a bunch of $3500 ADCs on it :p
<Degi>
I mean tbh the ethernet interface is great
<oskar>
ahaha
<Degi>
4 gigs of RAM? Like 4 GS of depth? Nobody else has that
<Degi>
Lol yeah
<Degi>
Tbh dont forget about the PCBs haha
<Degi>
Like doing a mistake on the middle layers of a 1k PCB
<azonenberg>
MAXWELL is happening first in part because there was a greater need for it right away, and in part because it
<azonenberg>
it's pure digital and more straightforward to a digital engineer like me
<monochroma>
Degi: wrt "OSH" yeah, i keep seeing people call the raspberry pi open source hardware... i... don't understand it :P
<monochroma>
and the OSH community seems to love them?
<azonenberg>
Degi: why do you think i bought that little benchtop mill?
<azonenberg>
and those 100 μm endmills?
<azonenberg>
Lol
<Degi>
I guess thats cheaper than reordering a PCB
<_whitenotifier-f>
[scopehal-docs] azonenberg pushed 2 commits to master [+0/-0/±2] https://git.io/Jfpqf
<_whitenotifier-f>
[scopehal-docs] miek 51918b3 - Document more Agilent/Keysight device support.
<_whitenotifier-f>
[scopehal-docs] azonenberg f87b59d - Merge pull request #12 from miek/more-agilent Document more Agilent/Keysight device support.
<azonenberg>
Degi: you mean a FIB?
<Degi>
yes
<azonenberg>
We have one at work for that express purpose
<Degi>
Oh loll really
<azonenberg>
Except instead of reworking buggy silicon we got it for adding new "bugs"
<Degi>
Hmh
<Degi>
Simulating radiation?
<azonenberg>
i.e. disabling code protect bits by physically rewiring them to the "off" state
<Degi>
Ah
<azonenberg>
that research program never really got off the ground but i want to push it more later on
<Degi>
Wonder if they can make custom gratings...
<azonenberg>
probably, at the nanoscale
<azonenberg>
making one big enough to see without a microscope would take days or weeks
<Degi>
Yeah probably
<azonenberg>
as someone who's used fibs before, not probably
<azonenberg>
definitely
<azonenberg>
:p
<Degi>
Hmh, making gratings should be possible with a good coherence laser and some basic photolithography stuff (silver plating solution, photomask, spin coater) lol
<Degi>
Well what if you just use a bigger ion source heh
<azonenberg>
the biggest thing i've made in a fib was a probe pad about 30x30 μm
<Degi>
Heh
<azonenberg>
it took probably half an hour
<Degi>
Can they deposit stuff too?
<azonenberg>
Yes, that's what i did there
<Degi>
Neat
<azonenberg>
a gas injector needle comes frighteningly close to the surface of your sample
<Degi>
Hmh sadly theres a big limitation with the high ion energies and deposition rate. Going too fast would melt a hole
<azonenberg>
then you heat up a volatile precursor like, say, tungsten hexacarbonyl
<azonenberg>
inject the gas into the area around the sample
<azonenberg>
a monolayer coats the surface of the sample, then dissociates when struck by the secondary electrons from the ion beam
<Degi>
Why not just use an electron beam?
<Degi>
Woow I can get that stuff from ebay lol
<azonenberg>
the nonvolatile metal sticks to the sample and the organic residues boil off and are removed by the vacuum system
<azonenberg>
Don't
<Degi>
Didnt expect carbonyls there
<azonenberg>
it's nasty stuff
<Degi>
Yes
<azonenberg>
anyway, you can actually do e-beam deposition. This is common for more sensitive samples since there's no ion damage
<azonenberg>
but it's much slower
<azonenberg>
common practice on sensitive samples for thick coatings is to do a thin e-beam platinum or tungsten layer to protect it
<azonenberg>
then switch to the ion beam once you have a bit of metal over it
<azonenberg>
so now you're only ion damaging the metal and not the specimen
<azonenberg>
You can even do chemically enhanced etching with a fib
<electronic_eel>
how much time does it take to get used to working on a FIB and get reliable results instead of damaging most of your samples?
<azonenberg>
injecting XeF2 gas
<azonenberg>
it breaks down into Xe and F2
<azonenberg>
then etches your sample where the beam is hitting it
<azonenberg>
(yes, it also etches the surroundigns, but it's much faster where the beam is)
<Degi>
Huh, XeF2...
<azonenberg>
Some collateral damage is expected when using it though
<Degi>
Hmh what limits the density of electrons? Beam widening from electrostatic repulsion?ß
<azonenberg>
in fact you can even open the gas injector and turn off the beam to do pure gas etching :p
<Degi>
Heh yeah
<Degi>
Awwh, ebay has no nickel tetracarbonyl...
<azonenberg>
Source brightness is a bunch of things, depends on the type of source for one (field emission, thermionic, etc)
<azonenberg>
generally there is an inverse tradeoff between beam current and resolution
<Degi>
Yes, I guess due to repulsion... Though you could use a neutral atom beam
<azonenberg>
a "brighter" source has more current per solid angle
<azonenberg>
you could but how would you accelerate them?
<azonenberg>
springs? rubber bands?
<Degi>
Well you accelerate ions and spray them with electrons when theyre fast
<Degi>
Or kick them with ions and then remove the ions
<azonenberg>
I have not seen that done. i have seen deceleration used to get super low beam energies
<azonenberg>
basically charge up the sample to almost the accelerating voltage
<azonenberg>
so the incoming beam slows down before hitting
<miek>
try to pick them up with tweezers, extreme acceleration guaranteed
<azonenberg>
you can get crazy low eV levels that way
<Degi>
I know the concept from plasma heating at least... Not sure how good its possible to focus it, since they'd be free flying after a focusing lens
<Degi>
Hmh yes, similar to a TWT
<Degi>
I too want a 40 megawatt NBI device for whateer lol
<Degi>
Accelerating 1 MeV with 40 A sounds fun
<Degi>
Like do they just hook up the nearest HVDC lines to it
<Degi>
I wonder if open loop cooling systems have problems with algae growth due to increased river temperatures... Like just dumping gigawatts into a river
<azonenberg>
We had algae growth in our closed sem/fib cooling loop
<sorear>
hmm, what do they use for gold-plating whole flies as SEM sample prep
<azonenberg>
sorear: sputter coating normally
<Degi>
I had black stuff growth in a distilled water tank with PLA endcaps... Replaced with PS and active deionization now its fins
<Degi>
Cool, theres some progress on iter right this motnh
<azonenberg>
<insert dr octopus quote here/>
<Degi>
Heh
<Degi>
Tbh there should be more investment into stellarator types...
<Degi>
They look really cool too
<sorear>
anything special this month or just the long steady drip of X coil shipped from Y to Z?
<Degi>
They put the cryostat bottom in
<Degi>
Its apparently the largest part of the thing
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<azonenberg>
monochroma: sfp+ to sma actually shipped this time :p