Totally. I bought the book ages ago, and read it for fun. I managed to have an email dialogue with Mr Mims, and thanked him for his ideas. What a nice guy.
Ask me anything :P I apologise for my mood at the end, I needed to draw a line and finish the video. If anyone has any tips on what I could try to fix the behavior, please share! I would even send some stickers and a 10mm LED for correct tips :D
@@Chris-rg6nm Interesting, I would have thought to decrease it more, instead. There has been quite a development on LEDs, maybe older just don't glow at that point. I will certainly use a pot at those current inputs to check it out.
I loved the video. Never noticed a negative mood. I bought the book ages ago, and that was the circuit design that jumped out at me as a must try. I am very glad you did it and posted a video because it gave me more motivation to try it. I think I might make it a sound sensitive wall art project. if someone makes a noise in the room or plays music it will react. Very nice video. I like seeing when others struggle with things too, as it lets me know I am not alone...lol
@@maarkaus48 thanks Maarkaus, makes me happy to hear all that! I'll see that I get an update out, once I find out how to "fix" it! Good luck with the fart indicator :P
I love those Forrest Mims books! I've built a bunch of projects from them over the years but never did get to the oscilloscope, though I did dream about doing it. This upscaled version is a fun project, I hope you work out the issue with the LEDs, it would make a great follow-up video!
I like your idea and building that led X&Y oscilloscope is amazing. I am looking forward to see you final version of that project. I believe it will end a very nice working oscilloscope. I will suggest that you put different led color in the center of the display vertical and horizontal. Thank you and please tell me where I can download the schematic.
Interesting suggestion to make that bug a feature and use different LEDs. The Matrix goes from 0V to 2.5V though, so having a line at 1.25V doesn't seem too obvious. There's no real schematics, but I can make one and get back to you. I kind of want to fix some bugs first, too.
at one point I had a 6k8 resistor on every eleventh LED :D I was very tired though. I think the first thing I should do is work on the 20 LED dev boards and then go from there again, secondly find better values for the current resistors.
LM's are internally isolated, however when running a analog low power circuit, it is generally accepted that you keep your bus traces the same width and lengths, and keep your capacitors close and tight tolerance.
@@Davedarko Analog noise ringing between Lms can cause artifact. filtering with capacitors can help filter this an the tracing and capacitors and tracing lengths create the high and or low pass filter
The Forrest M Mims notebooks got me started in electronics. I still recommend them to anyone else wanting to learn. They are fantastic books, and explain everything so well. It looks like maybe the LM chips don't like the current being driven into the output pins the opposite way. (and the pull-ups on the output pins of the other chips seem a bit too low value, and could be passing a fair bit of current through the open-collector drivers of those chips when there is no LED voltage drop there. The outputs only need to be logic-level to drive the inverter inputs, so I would try higher value pull-ups first, like say 2K2.) I guess there shouldn't be passing any current through the LEDs when the inverter outputs are low anyway, but I'm wondering if there might be some other weird effects there. Could maybe try some ULN2003 drivers as well... electronics.stackexchange.com/questions/221193/possible-to-drive-a-uln2003-driver-with-a-lm3914-bar-graph-display Although in theory, there should only be one column of LEDs driven at a time (based on the X input / inverters), maybe the inverters are still driving too many LEDs at once, or have some weird current paths through all of the LED junctions.
@@carlosoliveira1922 I would have to digitalise the signal with analog inputs and put that on the display - which makes it a completely different project and more software based. Totally possible though.
Why why? Motivation was: scale it up, use big LEDs to have something that looks nice in an IKEA shelf. Work with hardware that doesn't need MCUs and solder a bunch of LEDs to show some lissajous figurs on the matrix.
-"Element 14, the electronic design community where you can connect and collaborate with top engineers from around the world" Where is the top engineer in this episode? Hello??
Hello! Technically it says you can find the top engineers from around the world on the "element14 Community" www.element14.com/community/welcome and this is the youtube channel. I'm not claiming to be an engineer, I'm just a maker and I always try to do something that hasn't been done (too often) before. Forrest Mims is an engineer though and his book is called "Engineer's Notebook". Do you have any feedback on the content?
Those electronic notebooks from Forrest M. Mims III are still amazing.
indeed! Really great to have one here!
Totally. I bought the book ages ago, and read it for fun. I managed to have an email dialogue with Mr Mims, and thanked him for his ideas. What a nice guy.
Still got my set from 1990. Still useful.
Ask me anything :P I apologise for my mood at the end, I needed to draw a line and finish the video. If anyone has any tips on what I could try to fix the behavior, please share! I would even send some stickers and a 10mm LED for correct tips :D
@@Chris-rg6nm Interesting, I would have thought to decrease it more, instead. There has been quite a development on LEDs, maybe older just don't glow at that point. I will certainly use a pot at those current inputs to check it out.
@@Un_Pour_Tous thanks! Soldering 400 LEDs by hand is my new record :)
I loved the video. Never noticed a negative mood. I bought the book ages ago, and that was the circuit design that jumped out at me as a must try. I am very glad you did it and posted a video because it gave me more motivation to try it. I think I might make it a sound sensitive wall art project. if someone makes a noise in the room or plays music it will react.
Very nice video. I like seeing when others struggle with things too, as it lets me know I am not alone...lol
@@maarkaus48 thanks Maarkaus, makes me happy to hear all that! I'll see that I get an update out, once I find out how to "fix" it! Good luck with the fart indicator :P
@@Davedarko lol
I love those Forrest Mims books! I've built a bunch of projects from them over the years but never did get to the oscilloscope, though I did dream about doing it. This upscaled version is a fun project, I hope you work out the issue with the LEDs, it would make a great follow-up video!
thanks a bunch!
Awesome job Just Dave! :)
thanks! :)
I like your idea and building that led X&Y oscilloscope is amazing. I am looking forward to see you final version of that project. I believe it will end a very nice working oscilloscope. I will suggest that you put different led color in the center of the display vertical and horizontal. Thank you and please tell me where I can download the schematic.
Interesting suggestion to make that bug a feature and use different LEDs. The Matrix goes from 0V to 2.5V though, so having a line at 1.25V doesn't seem too obvious. There's no real schematics, but I can make one and get back to you. I kind of want to fix some bugs first, too.
What is the name of the work book, Please.
Hi, sorry for the late reply, it's "The Forrest Mims Engineer's Notebook"
Needs you to play Jerobeam Fenderson’s music through it
tried it, need to offset that from ac to dc :|
once again nice work with the LEDs.
wait, am I the LED guy now? :D
If you figure out the fix, please do post an update. Good luck!
will do, thanks!
You need to add a resistor across the first led output
at one point I had a 6k8 resistor on every eleventh LED :D I was very tired though. I think the first thing I should do is work on the 20 LED dev boards and then go from there again, secondly find better values for the current resistors.
Impressive to say the least. I hope you post the mods you did to make it x/y
will definitely be in an update section or on my channel :) thanks!
Hi Guys .. How to Fix you need to change on the LM 3915 IC from BAR to DOT Mode.. Check all common ground .
LM's are internally isolated, however when running a analog low power circuit, it is generally accepted that you keep your bus traces the same width and lengths, and keep your capacitors close and tight tolerance.
hi, not sure what this comment is related to? Do you expect wire widths on the pcbs to cause problems?
@@Davedarko Analog noise ringing between Lms can cause artifact. filtering with capacitors can help filter this an the tracing and capacitors and tracing lengths create the high and or low pass filter
You have way more patience than me Dave!
it was relaxing at some point, just watching netflix and "chill" by soldering loads of LEDs! Gah I'm such a nerd.
The Forrest M Mims notebooks got me started in electronics.
I still recommend them to anyone else wanting to learn. They are fantastic books, and explain everything so well.
It looks like maybe the LM chips don't like the current being driven into the output pins the opposite way.
(and the pull-ups on the output pins of the other chips seem a bit too low value, and could be passing a fair bit of current through the open-collector drivers of those chips when there is no LED voltage drop there. The outputs only need to be logic-level to drive the inverter inputs, so I would try higher value pull-ups first, like say 2K2.)
I guess there shouldn't be passing any current through the LEDs when the inverter outputs are low anyway, but I'm wondering if there might be some other weird effects there.
Could maybe try some ULN2003 drivers as well...
electronics.stackexchange.com/questions/221193/possible-to-drive-a-uln2003-driver-with-a-lm3914-bar-graph-display
Although in theory, there should only be one column of LEDs driven at a time (based on the X input / inverters), maybe the inverters are still driving too many LEDs at once, or have some weird current paths through all of the LED junctions.
Hey you have GreatScott's pen, Lol
They are handed to us Germans at birth :D
@@Davedarko I thought you got LAMY fountain pens at birth.
I guess times change. :)
@@ceneblock I do buy stabilo pens and eddings from time to time :)
How about make the output at an OLED display?
@@carlosoliveira1922 I would have to digitalise the signal with analog inputs and put that on the display - which makes it a completely different project and more software based. Totally possible though.
Nice
thanks! :)
Ey den Typen kenne ich von der MakerFair in Hannover XD
waaaas niemals :P MakerFaire war schon toll, hat Spaß gemacht :)
Ich auch...der ist echt überall!
Why?
Why why? Motivation was: scale it up, use big LEDs to have something that looks nice in an IKEA shelf. Work with hardware that doesn't need MCUs and solder a bunch of LEDs to show some lissajous figurs on the matrix.
@@Davedarko Fair enough. Mission accomplished.
-"Element 14, the electronic design community where you can connect and collaborate with top engineers from around the world"
Where is the top engineer in this episode? Hello??
Hello!
Technically it says you can find the top engineers from around the world on the "element14 Community" www.element14.com/community/welcome and this is the youtube channel. I'm not claiming to be an engineer, I'm just a maker and I always try to do something that hasn't been done (too often) before. Forrest Mims is an engineer though and his book is called "Engineer's Notebook". Do you have any feedback on the content?