Author Topic: HaasoscopePro AFFORDABLE open-source open-hardware 2 GHz oscilloscope!  (Read 8247 times)

0 Members and 1 Guest are viewing this topic.

Offline haastyleTopic starter

  • Contributor
  • Posts: 44
  • Country: us
You may recall the infamous Haasoscope, king of the worst schematics in history. (Dave did a 2 hour video based on it, just to explain how NOT to draw a schematic!)

Well I've learned a bit in the past 6 years, and now I've designed the Haasoscope Pro, quite the upgrade - now with 2 GHz of analog bandwidth. Each has 3.2 GS/s, but (before you go all Nyquist on me), you can sync 2 of them, to get to 6.4 GS/s interleaved.

All the designs are completely open-source and open-hardware ...
https://github.com/drandyhaas/HaasoscopePro/

It's now in pre-launch on CrowdSupply ...
https://www.crowdsupply.com/andy-haas/haasoscope-pro

Sign up there with your email to get updates as the project launches (next month?), and get first dibs on the introductory pricing for early backers.

Let me know what you think... What could be added or changed or improved etc.! Still plenty of time to make modifications - it's at the working prototype stage, but probably a couple months from production.
 
The following users thanked this post: oPossum, palpurul, tooki, Aiy, AnhGeek, steieio

Online tggzzz

  • Super Contributor
  • ***
  • Posts: 21468
  • Country: gb
  • Numbers, not adjectives
    • Having fun doing more, with less
Re: HaasoscopePro AFFORDABLE open-source open-hardware 2 GHz oscilloscope!
« Reply #1 on: December 07, 2024, 02:28:14 pm »
You may recall the infamous Haasoscope, king of the worst schematics in history. (Dave did a 2 hour video based on it, just to explain how NOT to draw a schematic!)
...
All the designs are completely open-source and open-hardware ...
https://github.com/drandyhaas/HaasoscopePro/

I'm certainly not going to spend 2 hours of my life on a yootoob vid, unless I know how I will benefit.

The haasoscope-pro PDF showing that schematic might be comprehensible to you with the aid of your design tools. It isn't to me. For example, you have an unconnected line with "NOFILT" on each end, ditto "NOSPLIT", and half of whatever is on P7 is missing, off the page.

Taking account of that lack of attention to detail and comprehensibility, I have to make guesses about how much attention has been paid to signal integrity and DRCs on that complex PCB....
« Last Edit: December 07, 2024, 02:38:05 pm by tggzzz »
There are lies, damned lies, statistics - and ADC/DAC specs.
Glider pilot's aphorism: "there is no substitute for span". Retort: "There is a substitute: skill+imagination. But you can buy span".
Having fun doing more, with less
 

Offline haastyleTopic starter

  • Contributor
  • Posts: 44
  • Country: us
Re: HaasoscopePro AFFORDABLE open-source open-hardware 2 GHz oscilloscope!
« Reply #2 on: December 07, 2024, 02:40:25 pm »
I'm sorry you had trouble understanding the schematic. Most people have not had any issue with it. The Nofilt line is pretty clearly just a connection through the DPDT relay. It's even labeled "relay". If you have a suggestion for how to make it more clear do please share!
 

Online tggzzz

  • Super Contributor
  • ***
  • Posts: 21468
  • Country: gb
  • Numbers, not adjectives
    • Having fun doing more, with less
Re: HaasoscopePro AFFORDABLE open-source open-hardware 2 GHz oscilloscope!
« Reply #3 on: December 07, 2024, 03:36:17 pm »
I'm sorry you had trouble understanding the schematic. Most people have not had any issue with it. The Nofilt line is pretty clearly just a connection through the DPDT relay. It's even labeled "relay". If you have a suggestion for how to make it more clear do please share!

No, it is not labelled "relay". There is no obvious indication of what the wire is connected to. I'm sure you know, but that's not the point.



How to make it clear is quite obvious: connect it, don't leave it flapping in the breeze. A flapping wire is exposing the netlist; netlists are for use inside EDA tools. (Exception: simple power and ground where layout/decoupling is standard and not especially important.

It isn't difficult, and the techniques were mature before I started in the 70s - and have been used ever since. If in doubt, have a look at any HP or Tektronix or Philips or Schlumberger or Fluke (etc etc) schematic.

And there are these illegibilities.



And you appear to confuse schematic symbols with PCB layout symbols. The schematic symbols should clearly indicate intent, e.g. inputs on left, outputs on right, control on top/bottom, related signals grouped together and separated from unrelated signals. All standard stuff.





Hells teeth, I was doing this in the late 80s in a version of Orcad for MSDOS - no mouse input, all keyboard driven. It isn't difficult - and was actually easier than contemporary GUI/mouse driven Mental Mentor Graphics schematic and PCB  EDA tools!
« Last Edit: December 07, 2024, 03:41:26 pm by tggzzz »
There are lies, damned lies, statistics - and ADC/DAC specs.
Glider pilot's aphorism: "there is no substitute for span". Retort: "There is a substitute: skill+imagination. But you can buy span".
Having fun doing more, with less
 

Offline haastyleTopic starter

  • Contributor
  • Posts: 44
  • Country: us
Re: HaasoscopePro AFFORDABLE open-source open-hardware 2 GHz oscilloscope!
« Reply #4 on: December 07, 2024, 04:13:21 pm »
Fair enough. I'll work on the text formatting in those few places. And I'll make nice looking schematic symbols at some point. It's much harder in Eagle than you'd think... Certainly harder than in the old days.
 

Online tggzzz

  • Super Contributor
  • ***
  • Posts: 21468
  • Country: gb
  • Numbers, not adjectives
    • Having fun doing more, with less
Re: HaasoscopePro AFFORDABLE open-source open-hardware 2 GHz oscilloscope!
« Reply #5 on: December 07, 2024, 04:42:03 pm »
Fair enough. I'll work on the text formatting in those few places. And I'll make nice looking schematic symbols at some point. It's much harder in Eagle than you'd think... Certainly harder than in the old days.

I find that creating schematic symbols doesn't take long. I also find that appropriate symbols and fully interconnected nets are both aesthetically pleasing and help me think about my design. A similar phenomenon is drawing, say, non-inverting opamp amplifiers with the components in the "traditional" positions. The software analogy is to use standard Design Patterns popularised by the GoF.

I can't comment on Eagle. When I last looked at Schematic/PCB tools a decade ago, I rejected Eagle on the grounds that it has a cliff-edge limit pins/components etc. Instead I chose something equivalent without limitations. I'm re-evaluating that now, and intend to look at KiCAD, since that has apparently improved significantly.

Good luck with your kickstarter.
There are lies, damned lies, statistics - and ADC/DAC specs.
Glider pilot's aphorism: "there is no substitute for span". Retort: "There is a substitute: skill+imagination. But you can buy span".
Having fun doing more, with less
 

Offline Bud

  • Super Contributor
  • ***
  • Posts: 7303
  • Country: ca
Re: HaasoscopePro AFFORDABLE open-source open-hardware 2 GHz oscilloscope!
« Reply #6 on: December 07, 2024, 07:01:55 pm »
There is no way in efking hell I would try a schematic where components are not connected with lines. What is wrong with you people?
Facebook-free life and Rigol-free shack.
 
The following users thanked this post: 2N3055

Online tggzzz

  • Super Contributor
  • ***
  • Posts: 21468
  • Country: gb
  • Numbers, not adjectives
    • Having fun doing more, with less
Re: HaasoscopePro AFFORDABLE open-source open-hardware 2 GHz oscilloscope!
« Reply #7 on: December 07, 2024, 08:11:13 pm »
There is no way in efking hell I would try a schematic where components are not connected with lines. What is wrong with you people?

It is distressingly common.

My conjecture, without evidence, is that people with a software background dabbling with hardware transpose software habits into the hardware domain. Software design tools (IDEs) easily navigate text-only designs, and hardware design tools don't prevent it.

Similarly I conjecture that schematics with right-to-left signal flows may have been created by people where their first written language flows in that direction.
There are lies, damned lies, statistics - and ADC/DAC specs.
Glider pilot's aphorism: "there is no substitute for span". Retort: "There is a substitute: skill+imagination. But you can buy span".
Having fun doing more, with less
 

Offline nfmax

  • Super Contributor
  • ***
  • Posts: 1627
  • Country: gb
Re: HaasoscopePro AFFORDABLE open-source open-hardware 2 GHz oscilloscope!
« Reply #8 on: December 07, 2024, 08:18:18 pm »
[quote author=tggzzz link=topic=446637.msg5739821#msg573982
Similarly I conjecture that schematics with right-to-left signal flows may have been created by people where their first written language flows in that direction.
[/quote]

Interestingly, looking at some the 1920 era schematic circuit diagrams in Wireless World (on the worldradiohistory website), that convention was by no means generally observed.
 

Offline haastyleTopic starter

  • Contributor
  • Posts: 44
  • Country: us
Re: HaasoscopePro AFFORDABLE open-source open-hardware 2 GHz oscilloscope!
« Reply #9 on: December 07, 2024, 08:23:31 pm »
Already fixed those easy issues...
 

Online tggzzz

  • Super Contributor
  • ***
  • Posts: 21468
  • Country: gb
  • Numbers, not adjectives
    • Having fun doing more, with less
Re: HaasoscopePro AFFORDABLE open-source open-hardware 2 GHz oscilloscope!
« Reply #10 on: December 07, 2024, 08:27:41 pm »
Quote from: tggzzz link=topic=446637.msg5739821#msg573982
Similarly I conjecture that schematics with right-to-left signal flows may have been created by people where their first written language flows in that direction.

Interestingly, looking at some the 1920 era schematic circuit diagrams in Wireless World (on the worldradiohistory website), that convention was by no means generally observed.

Fair point.

I wonder if that was partly as a result of the systems having very few components and hence signal flow only being a vestigial concept, partly due to handing off drawings to specialised draftsmen who don't understand them, partly due to scrappy tools and laziness.

At school I remember a math teacher complaining that it was difficult for her to read our Algol60 programs since they weren't indented consistently. Fair point, but editing a program on 5 channel paper tape with a  5cps teleprinter was a major pain :)

Back in the rubylith days, it was common for PCB draftsmen to refuse to move a track after they had placed it :)
« Last Edit: December 07, 2024, 08:32:49 pm by tggzzz »
There are lies, damned lies, statistics - and ADC/DAC specs.
Glider pilot's aphorism: "there is no substitute for span". Retort: "There is a substitute: skill+imagination. But you can buy span".
Having fun doing more, with less
 

Offline artag

  • Super Contributor
  • ***
  • Posts: 1312
  • Country: gb
Re: HaasoscopePro AFFORDABLE open-source open-hardware 2 GHz oscilloscope!
« Reply #11 on: December 07, 2024, 08:28:28 pm »
Fair enough. I'll work on the text formatting in those few places. And I'll make nice looking schematic symbols at some point. It's much harder in Eagle than you'd think... Certainly harder than in the old days.

It's your project, but Eagle probably isn't the way to go for a project with open-source intentions and a hoped-for long life.
 

Offline haastyleTopic starter

  • Contributor
  • Posts: 44
  • Country: us
Re: HaasoscopePro AFFORDABLE open-source open-hardware 2 GHz oscilloscope!
« Reply #12 on: December 07, 2024, 08:34:20 pm »
Agreed. Fortunately, I've checked that the eagle files can be imported easily into KiCAD. I'm not confident enough with them yet to add to the repository. I'm still just learning it. But at least I'm confident that the design can live on indefinitely.
 

Online 2N3055

  • Super Contributor
  • ***
  • Posts: 7556
  • Country: hr
Re: HaasoscopePro AFFORDABLE open-source open-hardware 2 GHz oscilloscope!
« Reply #13 on: December 07, 2024, 08:35:46 pm »
There is no way in efking hell I would try a schematic where components are not connected with lines. What is wrong with you people?

It is distressingly common.

My conjecture, without evidence, is that people with a software background dabbling with hardware transpose software habits into the hardware domain. Software design tools (IDEs) easily navigate text-only designs, and hardware design tools don't prevent it.

Similarly I conjecture that schematics with right-to-left signal flows may have been created by people where their first written language flows in that direction.

Without going into details of how and many ways it has been done through the years, the dead giveaway should be the "schematic diagram", as in a drawing that shows (in a graphical way) components and their interconnections.

Printing out netlist is not a schematic.. Period.
"Just hard work is not enough - it must be applied sensibly."
Dr. Richard W. Hamming
 

Offline shabaz

  • Frequent Contributor
  • **
  • Posts: 613
Re: HaasoscopePro AFFORDABLE open-source open-hardware 2 GHz oscilloscope!
« Reply #14 on: December 07, 2024, 08:59:03 pm »
Fortunately, I've checked that the eagle files can be imported easily into KiCAD.

It is easy, but the devil is in the detail.

There isn't a 1:1 mapping of features identically between different CAD packages. KiCad does what it can, but it is up to the person doing the project porting to modify things such as footprints, to use KiCad features in a more normal manner than an automated project port can achieve.

With a large project, that would be a big barrier for anyone who wished to make some changes. Just clicking to do the automated port unfortunately isn't all that helpful, since anyone can do that.

Anyway, I have to say, that's still just a detail, the more major issue is indeed the schematics are very hard to follow. EAGLE does allow for logical symbol layout. FPGA and other large pin-count devices can be split up into separate sub-components, for instance, the supply and config pins could have their own symbol (logically arranged with supply pins on top, ground at bottom, etc). This is achievable in EAGLE.


« Last Edit: December 07, 2024, 09:03:18 pm by shabaz »
 

Offline julian1

  • Frequent Contributor
  • **
  • Posts: 774
  • Country: au
Re: HaasoscopePro AFFORDABLE open-source open-hardware 2 GHz oscilloscope!
« Reply #15 on: December 07, 2024, 10:17:41 pm »
really impressive project.
Am I right in thinking the heart of the trigger engine, is in the command processor?
https://github.com/drandyhaas/HaasoscopePro/blob/main/adc%20board%20firmware/command_processor.v
eg. taking the adc's LVDS/serdes stream, after converting/encoding to AXI?
this then controls buffering?
I should watch the video.
 

Offline haastyleTopic starter

  • Contributor
  • Posts: 44
  • Country: us
Re: HaasoscopePro AFFORDABLE open-source open-hardware 2 GHz oscilloscope!
« Reply #16 on: December 08, 2024, 04:39:13 am »
Thanks. Yes, the (simple, for now) trigger starts there:
https://github.com/drandyhaas/HaasoscopePro/blob/3a6c011b44fdada14aa9471a597ff9cbdba43bc0/adc%20board%20firmware/command_processor.v#L399

The lvds inputs are converted to an array of 40 12-bit samples per lvds clock cycle, and the trigger acts on those. When the trigger occurs, the circular input buffer is frozen and waits for readout.

There's no fancy video yet, but I have been writing about the project here:
https://hackaday.io/project/200773-haasoscope-pro
 
The following users thanked this post: julian1

Offline Nominal Animal

  • Super Contributor
  • ***
  • Posts: 7314
  • Country: fi
    • My home page and email address
Re: HaasoscopePro AFFORDABLE open-source open-hardware 2 GHz oscilloscope!
« Reply #17 on: December 08, 2024, 05:57:05 am »
There is no way in efking hell I would try a schematic where components are not connected with lines. What is wrong with you people?

It is distressingly common.

My conjecture, without evidence, is that people with a software background dabbling with hardware transpose software habits into the hardware domain. Software design tools (IDEs) easily navigate text-only designs, and hardware design tools don't prevent it.
You definitely have something there, regarding my own habits (when using EasyEda online schematic and PCB editor).

When designing a circuit, I don't care about the placement of the tracks, and net labels make them invisible and thus reduce my cognitive load.  I do like to try and keep each modular unit fully connected –– any group of components that perform a specific task, that I can replace with something else, when refactoring the schematic or minimizing the BOM cost –– and find OP's schematic scattering into individual separate ICs extremely confusing, too.  If a module does not fit, just use larger sheet.  (At least EasyEda and KiCad support this; I don't see why any schematic editor wouldn't.)

For example, in this design I have the three connectors on the left, the power supply (and supply enable) stuff at top, PWM level shifting circuitry at bottom center, and tachometer level shifting on the right.  This way I can think of each one in isolation, and this helps me manage things.  (I know the schematic could be better, too.)

It is much easier for me to read this kind of a grouped/modular schematic, than one where everything is connected via visible wires.  (And I still occasionally mix a bus with a single wire with lots of branches.  So, I do expect this to change if I work with schematics enough.)  When I switch to PCB design, I use the ratsnest option (that shows which pads/wires need to be connected together with directly connected visual lines and highlights), so I don't need to think about routing at the schematic design phase.  This really helps me get things going, step by step.

I suspect that people like myself with software backgrounds probably find this modularity easier than fully connected schematics, simply because they don't have the experience to quickly comprehend and mentally modularize fully connected schematics.  I do assume/believe that those with lots of EE schematic capture experience do that kind of modularization without thinking about it or even realizing they do it, because when I look at DiodeGoneWild or BigClive explaining their reverse-engineered schematics, their grouping of the components and parts follow mine; and when a component has multiple purposes, it tends to throw them off too (as such multipurpose components do not fit cleanly into a modular model of the circuit).

Note: I'm not claiming any of this is right/better/correct!

I'm just explaining the reasons I have for doing it that way, and how I believe my reasons doing it that way relate to both hobbyists with software backgrounds, and those with proper experience in schematic capture.  The only thing I ask is forgiveness for not having the skills yet to do it right, as my skills are still barely enough to get it done this crude way.  Suggestions for improvement are gold, but seeing the deficiencies said to be "distressing" is alarming.  I definitely agree that having inputs on the left, outputs on the right, makes it easier for me to understand even the modular schematics with lots of net labels; as does having positive voltages above and ground and negative voltages below.  I'm just not skilled enough yet to achieve all those desired goals!  (So I assume neither are the other myriad hobbyists.)  In the meantime, I do still show my scribblings, although I want to point out that their crudity and my willingness/hopefulness in receiving criticism and learn from my mistakes is why they're all in Public Domain / CC0-1.0.
« Last Edit: December 08, 2024, 06:11:19 am by Nominal Animal »
 

Online tggzzz

  • Super Contributor
  • ***
  • Posts: 21468
  • Country: gb
  • Numbers, not adjectives
    • Having fun doing more, with less
Re: HaasoscopePro AFFORDABLE open-source open-hardware 2 GHz oscilloscope!
« Reply #18 on: December 08, 2024, 11:43:16 am »
There is no way in efking hell I would try a schematic where components are not connected with lines. What is wrong with you people?

It is distressingly common.

My conjecture, without evidence, is that people with a software background dabbling with hardware transpose software habits into the hardware domain. Software design tools (IDEs) easily navigate text-only designs, and hardware design tools don't prevent it.
You definitely have something there, regarding my own habits (when using EasyEda online schematic and PCB editor).

When designing a circuit, I don't care about the placement of the tracks, and net labels make them invisible and thus reduce my cognitive load.  I do like to try and keep each modular unit fully connected –– any group of components that perform a specific task, that I can replace with something else, when refactoring the schematic or minimizing the BOM cost –– and find OP's schematic scattering into individual separate ICs extremely confusing, too.  If a module does not fit, just use larger sheet.  (At least EasyEda and KiCad support this; I don't see why any schematic editor wouldn't.)

For example, in this design I have the three connectors on the left, the power supply (and supply enable) stuff at top, PWM level shifting circuitry at bottom center, and tachometer level shifting on the right.  This way I can think of each one in isolation, and this helps me manage things.  (I know the schematic could be better, too.)

It is much easier for me to read this kind of a grouped/modular schematic, than one where everything is connected via visible wires. 

I think that is fine.

Separating independent sections is natural, and becomes a requirement in a large diagram, one section per sheet. The PSU is a classic example of that.

Each of your sections has an independent "signal flow", so there is no need to mentally insert the connections. By contrast the OP splits out tiny sub sub sections which obscures the signal flow, leaving reader to wonder what the signal flow is: where does it start, where does it end, and have I spotted all the connections.

A connector that has a large number of logically unrelated signals is a classic pain point. The way to think about it is to consider a reader starting at the connector, and trying to work out which bit of the circuit deals with each signal. It is normal to have large connectors shown as a single component, with labelled wires coming out.

In good schematics there will be an annotation indicating "the other end" of the wire. Sometimes that will be "to Sheet5 Q1" (and the other end of the wire reverse labelled  "to Sheet1 Conn6". Other times there will be a "top level" schematic showing all interconnections between subcircuits, a bit like the main() function in a C program.

Quote
(And I still occasionally mix a bus with a single wire with lots of branches.  So, I do expect this to change if I work with schematics enough.) 

Again, that's fine - provided each wire is named where it enters/exits the bus. All the reader has to do is follow the bus to find out all the connections. Classic examples are address busses, data busses, and control busses (R/W, CS, etc).

Quote
When I switch to PCB design, I use the ratsnest option (that shows which pads/wires need to be connected together with directly connected visual lines and highlights), so I don't need to think about routing at the schematic design phase.  This really helps me get things going, step by step.

Again, that's perfectly standard.

Sometimes it is known when creating the schematic that certain PCB rules will have to be followed, e.g, differential pair matched length or impedance control. With simple tool for small designs, those constraints can be simple text annotations. In complex tools for big designs where a different person does the PCB layout, such properties can be entered into the schematic, and the tool will (hopefully) ensure the PCB layout person has complied.

In the cases where, say, several signals are individually buffered before going off-board (e.g. a control bus with inverters), the schematic designer will wire them up without knowing the detailed PCB layout. That may cause an unnecessarily tangled set of wires, and it is perfectly reasonable for the PCB person to swap pins. Such swaps are then automatically back-annotated into the schematic.

Quote
I suspect that people like myself with software backgrounds probably find this modularity easier than fully connected schematics, simply because they don't have the experience to quickly comprehend and mentally modularize fully connected schematics. 

There I disagree. "Coupling and cohesion" are the same in hardware and software. The question is how to think about and denote that.

Analogies are always dangerous, but consider each small subsection being a function. It would be ridiculous to have multiple source files and to scatter each function  across the different files. It makes much more sense to gather related functions into, say, a (singleton) class with each class being in a separate file.

Quote
I do assume/believe that those with lots of EE schematic capture experience do that kind of modularization without thinking about it or even realizing they do it, because when I look at DiodeGoneWild or BigClive explaining their reverse-engineered schematics, their grouping of the components and parts follow mine; and when a component has multiple purposes, it tends to throw them off too (as such multipurpose components do not fit cleanly into a modular model of the circuit).

Reverse engineering is, arguably, irrelevant. When you are creating a design and schematic, that is forward engineering.

Your examples are more like someone looking at machine code and trying to work out what's happening. That's a very different task with very different objectives.

Quote
I'm just explaining the reasons I have for doing it that way, and how I believe my reasons doing it that way relate to both hobbyists with software backgrounds, and those with proper experience in schematic capture.  The only thing I ask is forgiveness for not having the skills yet to do it right, as my skills are still barely enough to get it done this crude way.  Suggestions for improvement are gold, but seeing the deficiencies said to be "distressing" is alarming.  I definitely agree that having inputs on the left, outputs on the right, makes it easier for me to understand even the modular schematics with lots of net labels; as does having positive voltages above and ground and negative voltages below.  I'm just not skilled enough yet to achieve all those desired goals!  (So I assume neither are the other myriad hobbyists.)  In the meantime, I do still show my scribblings, although I want to point out that their crudity and my willingness/hopefulness in receiving criticism and learn from my mistakes is why they're all in Public Domain / CC0-1.0.

All just fine and understandable.

Techniques that aren't a problem with small designs, don't scale to large designs. That's why you can't use BASIC for large programs.

Fundamentally it is a matter of understandability and good taste. An engineer ought to be able to comprehend the former, but the latter cannot be taught!
There are lies, damned lies, statistics - and ADC/DAC specs.
Glider pilot's aphorism: "there is no substitute for span". Retort: "There is a substitute: skill+imagination. But you can buy span".
Having fun doing more, with less
 

Offline janoc

  • Super Contributor
  • ***
  • Posts: 3940
  • Country: de
Re: HaasoscopePro AFFORDABLE open-source open-hardware 2 GHz oscilloscope!
« Reply #19 on: December 08, 2024, 01:39:46 pm »
There is no way in efking hell I would try a schematic where components are not connected with lines. What is wrong with you people?

It is distressingly common.

My conjecture, without evidence, is that people with a software background dabbling with hardware transpose software habits into the hardware domain. Software design tools (IDEs) easily navigate text-only designs, and hardware design tools don't prevent it.

Similarly I conjecture that schematics with right-to-left signal flows may have been created by people where their first written language flows in that direction.

That conjecture is just that - a conjecture. There is nothing in software that would lead one to draw a schematic like that - I have 25 years of sw work under my belt, one would think that if that was the case, it would have manifested itself on the schematics I draw.

It is crappy Youtube tutorial videos done by people not knowing any better and newbies who learn from those videos (reading is soo out these days) cargo-culting what they see without understanding (labels? check. big fat boxes around every component? check. no crossing wires? check! And don't ever ever draw right angle traces!) because nobody actually explains the principles behind drawing a schematic in those videos.

That has little to do with software and everything with the low quality crap being published everywhere, with the major platforms incentivizing the 10 minute "bite-sized" content catering to people with an attention span of a fruit fly. So for a beginner it is a tall order to expect that they will be able to filter the crap out and recognize what is good to copy and what isn't. I remember my own surprise and disillusionment many moons ago when I have discovered that not every circuit published in a magazine (that was long time before we had internet or web) actually works or is a good design ... It is on paper in a magazine, so it has to be true/good, right? And that was an actual paper magazine that had an editor and publisher and required photos of the working assembled circuit in order to publish it.

These days anyone can publish anything - be it an electronic tutorial or a recipe how to cure covid by drinking bleach.

It is actually quite telling that the OP has still problems drawing a decent schematic, despite Dave actually redoing the first version for them for free, including all the tips and explanations:
https://youtu.be/R_Ud-FxUw0g

When people get feedback and still ignore it, vote with your feet. 
« Last Edit: December 08, 2024, 01:55:59 pm by janoc »
 

Offline haastyleTopic starter

  • Contributor
  • Posts: 44
  • Country: us
Re: HaasoscopePro AFFORDABLE open-source open-hardware 2 GHz oscilloscope!
« Reply #20 on: December 08, 2024, 02:57:49 pm »
This new schematic is pretty good. Far better than the original Dave used as an example. Is it perfect? No. But I consider myself to have made impressive progress. And it's not done yet. Let's work together and be constructive please.
 

Offline Bud

  • Super Contributor
  • ***
  • Posts: 7303
  • Country: ca
Re: HaasoscopePro AFFORDABLE open-source open-hardware 2 GHz oscilloscope!
« Reply #21 on: December 08, 2024, 07:16:44 pm »
There is no way in efking hell I would try a schematic where components are not connected with lines. What is wrong with you people?

It is distressingly common.

My conjecture, without evidence, is that people with a software background dabbling with hardware transpose software habits into the hardware domain. Software design tools (IDEs) easily navigate text-only designs, and hardware design tools don't prevent it.
Right, it seems to me too that the rise of this poor practice started with mass availability of inexpensive FPGAs, many FPGAs projects appeared that had interesting software features but shockingly bad schematic diagrams like this one and abysmal PCB designs.
Facebook-free life and Rigol-free shack.
 

Online tggzzz

  • Super Contributor
  • ***
  • Posts: 21468
  • Country: gb
  • Numbers, not adjectives
    • Having fun doing more, with less
Re: HaasoscopePro AFFORDABLE open-source open-hardware 2 GHz oscilloscope!
« Reply #22 on: December 08, 2024, 07:34:29 pm »
This new schematic is pretty good. Far better than the original Dave used as an example. Is it perfect? No. But I consider myself to have made impressive progress. And it's not done yet. Let's work together and be constructive please.

We don't know anything about you beyond your statement "Professor of Physics by day and open-source/open-hardware tinkerer by night", so we can only judge based on what we can see in github.

To get microwave circuits like this working reliably (i.e. no temperature / tolerance / pattern sensitive infelicities) requires more than mere "tinkering" :)

Having a quick look at your PCB, you don't mention your stackup, the analogue input circuits don't seem to minimise track length, and I wonder if things marked 50ohm in the schematic really are 50ohm.

Personally I wish you luck with your kickstarter, but I wouldn't think of investing until you demonstrated it working - preferably plus a review of the prototype by an independent engineer.
There are lies, damned lies, statistics - and ADC/DAC specs.
Glider pilot's aphorism: "there is no substitute for span". Retort: "There is a substitute: skill+imagination. But you can buy span".
Having fun doing more, with less
 
The following users thanked this post: janoc

Offline haastyleTopic starter

  • Contributor
  • Posts: 44
  • Country: us
Re: HaasoscopePro AFFORDABLE open-source open-hardware 2 GHz oscilloscope!
« Reply #23 on: December 08, 2024, 09:51:27 pm »

Having a quick look at your PCB, you don't mention your stackup, the analogue input circuits don't seem to minimise track length, and I wonder if things marked 50ohm in the schematic really are 50ohm.

Personally I wish you luck with your kickstarter, but I wouldn't think of investing until you demonstrated it working - preferably plus a review of the prototype by an independent engineer.

Very legitimate concerns!
I am writing more about the project over here:
https://hackaday.io/project/200773-haasoscope-pro

The stackup is 10-layer, sig1 gnd sig2 gnd pwr1 pwr2 gnd sig3 gnd sig4. Impedance controlled pcb of course. I made test boards and tested track impedance with a nano vna plus.

It definitely works. I've tested with a Leo Bodner pulse generator with 40ps riserime, and I see about a 200 ps risetime. I'm fine tuning the multi board oversampling now, which will get up to 6.4GS/s, at which point I'll be able to test the bandwidth more accurately.

There will certainly be videos, plots, etc demonstrating the performance before the project launches next month. At the moment we are just in pre-launch.
There will also be independent reviews. Hopefully even one from Dave again.
 

Offline KE5FX

  • Super Contributor
  • ***
  • Posts: 2113
  • Country: us
    • KE5FX.COM
Re: HaasoscopePro AFFORDABLE open-source open-hardware 2 GHz oscilloscope!
« Reply #24 on: December 09, 2024, 01:03:19 am »
This new schematic is pretty good. Far better than the original Dave used as an example. Is it perfect? No. But I consider myself to have made impressive progress. And it's not done yet. Let's work together and be constructive please.

Damn the anklebiters, full speed ahead.  That schematic is a hell of a lot better than what they'll get from Keysight, Tek, R&S, or Siglent.  8)

The best answer to the critics is a nice demo video.  Sounds like you're almost there.
 
The following users thanked this post: haastyle


Share me

Digg  Facebook  SlashDot  Delicious  Technorati  Twitter  Google  Yahoo
Smf