Yann Guidon / YGDES
Lutetium
Dr. Cockroach
Arsenijs
al1
Morning.Star
LazyHD-
Help with calibration of a digital lab PSU
07/27/2017 at 00:23 • 14 commentsI just found out that my new shiny cheap lab PSU is 5% to 10% off !
It has a nice resolution but the readings in both V and A don't match my measurements with an external multimeter...
The model AX6002P from Axiomet is similar to the better known Velleman or KORAD KA6002P so it might be a known issue....
Update 20170730:My "golden tester"'s battery is a bit low (8.5V) so I changed with a fresh one (curious since I changed it less than a year ago).
I tested the measurements against other multimeters, checked the power supplies and ... all values are coherent within the respective accuracies.
Bad battery. Case closed. Sorry for the alarm. But the question is still good and it would be cool to be able to calibrate the device "if something happened" :-)
-
Another eBay horror story
10/28/2016 at 15:20 • 0 commentsI have more than 400 stars and have purchased hundreds and hundreds of items on eBay.
I have had some occasional troubles and lately, more than before.
But even though the last story is worth a laugh (at my expense but only some tens of USD and at least I have very nice example of Chinese counterfeit gone wild) today's story is more of the "grieving" kind.
As some of you know, I've been bitten by the speed demon again. I want to play with discrete ECL gates and I need the fastest scope I can reasonably get (as if I needed an excuse to get the best gear for my lab). No DSO for me, because I don't trust them enough (at my price point at least), and it seems the fastest analog scope can reach 500MHz for some theoretical reasons (damned RC constants !). But even if I can't fully exploit the 500MHz "bandwidth" of the AF240, there can be all sorts of "very fast" circuits to design in the foreseeable future. For example, I have 250MHz SSRAMs and the lousy FPGA I use are rated up to 350MHz.
Recently I found an amazing deal: a Tektronix 2465 with original probes, anno 1995 is perfect condition, for a very affordable price and the shipping+customs was nice too. Sorry, no name, it was the last one of a batch... Very fast shipping (5 days from order to delivery), well packaged (sheets over sheets of bubble wrap), works great and will do for the coming 20 years (if I can hack the backup battery). Price: 150 USD, shipping: 42.64 USD, customs: 38.49USD. Total : 231.13 USD with expedited "international shipping program". A steal. Tek-love at first sight.
But 4×300MHz doesn't cut it and I have no idea what signals I'll have to treat in the coming decade or two. I need an analog speed demon. I looked around and the suspect is the Tektronix 11302, a modular "boat anchor" capable of 500MHz with bells, whistles and even a drum. The last of a long lineage of Tektro tradition. I found the service manual, looked at forums to get an idea and browsed eBay.
I found one in Italy (close to my French home) for about $300 and $60 shipping. Nice but only one 11A32 (2×400MHz) module. That doesn't scratch the surface. Looking at spare modules, I see that the price will climb quicky if I want to populate the other 2 free slots (one slot cover is missing, which is "no-no"-ed in the service manual, but that's a detail).
Then I found a well-equiped 11302 (not 11302A) with 2×11A32 (same 2×400MHz as above) and one 11A71 (1GHz@50 Ohms, yipeeee) in the USofA (but no probe). Seller writes: "Garanteed" and "use ebay's global shipping program". So I "bid in confidence". And win !
I'm elated by the 2465 and happy that it has a big brother, gotten for barely more: around 180$ only ! The seller has thousands of stars, the unit works, so what could go wrong ?
Let's start with the time taken to decide about shipment, which added a bit of suspense.
Some pictures:
I find a peace of plastic while I remove the flakes. What can it be ? Oh, a foot...
The unit still in the box, most of the flakes have been removed: there is only one layer of thin bubble wrap in the frond and in the back. One more layer around.
Surprise: another foot is missing !
And the case shows a bump
The unit sitting on it side. The screen is "falling" inside its frame. Not good!!!
The broken screen
The tube is not repairable. Changing it requires a complete recalibration, if I ever find a spare part, which, for price, the would come as another complete unit...
The scope was obviously improperly packaged.
The cardboard box sustained most of the damage but was slightly deformed. Sorry I didn't think I should take a picture because I thought it was well protected inside.
The big mistake was with the filling. The unit should have been copiously wrapped in a lot of thick bubble wrap sheets. The previous scope (2465) came with bubble wrap only. Not only did...
Read more » -
Oh the difficulty of sourcing P-MOSFET in TO-92
08/29/2016 at 02:42 • 4 commentsIf you follow Yet Another (Discrete) Clock, you know this project uses quite a lot of MOSFET in the easy-to-solder TO-92 package. A bit less than 500, including about 300 N-FET (BS170 or 2N7000) and the rest are P-FET (BS250).
The N-FET are OK: I could source 300×2N7000 for around 10$, 3 cents per piece is a nice deal and a decent price for the project.
The P-FET are another story :I could find cheap reels in SOT23 but the prices are much higher for the TO-92 package and there seems to be a sort of shortage in the usual cheap markets. Earlier this year, an order never made it to my home (among other postal problems) and a 200pc lot was found to have a reverse pinout (https://hackaday.io/project/9376-yet-another-discrete-clock/log/37927-it-was-too-easy).
This post is about another escalation in the BS250 horror story. I found a decently priced lot of 100 on eBay (due to Brexit) and this time ordered only one lot (I was not feeling rich, and at 20GBP, or about 24€ for 100, the unit price is almost 10× higher than the N-channel). Since the precedent lot (2×100) was functional (despite the reversed pinout) and was delivered, I bought from the same seller. Delivery was pretty fast (maybe due to summer vacations and less business) so I was ready to leave another good feedback.
Just to be sure, I tested a few parts from the bag. I don't remember why but you never know, and I wondered what was the pinout this time. Guess what ? I found a MOSET but in N-channel, not P. WTF ? It's marked "BS250" !
I take another then another and start to find a "mixed bag"
- Some parts are indeed P-channel but a minority
- Most are N-channel
- Some weird arrangements, like dual diodes, or very malformed junctions
- The surface of several packages look altered, like attacked by acid, and a couple have no marking. Others have a different style of marking...
After I sent a complaint to the seller, I received the following:
« Hi,client.So sorry for your trouble.Could you let me know how many pieces are not working as excepted,I will check with our supplier for this issue.Regards, Namedeleted »
Wait, you send me worse-than-counterfeit parts then you want me to do your job, for which I paid you ?
Alright, since you wanted it, let's waste 2 hours testing all the parts by hand.
I could identify:
- 25×P-channel (more or less BS250, I only tested the simplest parameters)
- 61×N-channel (some sort of 2N7000 but I didn't care about the pinout)
- The rest are malformed, non-functional parts.
Only 1/4 of the order can qualify as conform.
Ah, China...
Pictures to come...
My Projects
Projects I Contribute To
My Pages
Things I've Built
1KW LED lighting
2006: I designed and built all the electronics of a store's architectural element. 432 3W Luxeon LEDs split in 9 sectors with independent dimming with my first HTTP-based remote controller...
Lambda
LED desk lamp concept design. 2008
Drosephyia
Working as SubFlower, Igor & I built a sort of electronic plant in 2005 for an exhibition at Biche de Bere art gallery.
Projects I Like & Follow
Luke Valenty
agp.cooper
Ruud van Falier
KnivD
zakqwy
tomtibbetts
klemas
matseng
Ted Yapo
Dave's Dev Lab
Pavel
legacy
Marcel van Kervinck
Bruce Land
lloShare this profile
ShareBits
Hello F4HDK, and thank you for your bits :-)
You raise several important questions and I'll try to address them here quickly.
"It's really difficult to understand the organisation of all these projects, and therefore it is difficult to understand all your work." Yes I agree and I still consider creating a "metaproject" but HaD is not flexible enough for this. It would probably be a "projects map", some sort of 2D graph that links and groups the projects depending on their purposes, characteristics etc.
But since I'm lazy AND crazy busy on other fronts (I have to earn my living) I'll do a quick recap on the subject that seems dear to our hearts.
"Why so many CPU projects? I really don't understand. I've seen 13 CPU projects from you on hackaday. That's huge!" This is because each project serves to explore a given angle. CPU architecture design is easy, "back of an envelope", and is not covered in many projects. However implementation is the real deal and it explains why the project count has bloated lately. The last aspect is that each project creates spin-offs when one problem requires a specific and new development.
But basically you can start with 3 major CPU families : F-CPU (64/32 bits), YASEP (32/16 bits) and YGREC (16/8 bits), in chronological order.
* #F-CPU started around 1998, 20 years ago, I joined it and took more and more responsibilities, drafted the FC0 (a clever monster) and the project slowly died from bikeshedding. I vowed to revive it by fixing all the flaws (structural, organisational etc.) but I had to address all these flaws... You have to remember that 15 years ago, the state of Open Source Hardware was not what it is today. We had to re-invent everything and this greatly exceeded the project's scope. Oh and we wanted to create a desktop-class CPU when nobody had made a simple working one before.
* the #YASEP Yet Another Small Embedded Processor is a much simpler core for a very different purpose/application, so I could focus on the tools and framework. It started as a 32 bits CPU and was soon able to be 16 bits wide too. It achieved "simulation status" around 2013 when it computed a Mandelbrot set.
It gave birth to #YGWM Whygee's JavaScript Window Manager which is a crazy JS spaghetti monster. I joined HaD to find help to rewrite it from scratch with better coding patterns. I soon become exhausted from writing code (I missed the real action and my soldering iron was rusting) and started #Discrete YASEP (with a specific use in mind). From there #DYPLED appeared.
* The "discrete computer projects" are "toy computers" I've known about for along time (http://members.iinet.net.au/~daveb/simplex/ringhome.html was not created yesterday) and I finally gave in because I was fed up with software, I want to 1) touch what I do (much easier to debug) 2) teach about computers with stunning pieces of living electronics 3) have FUN !
Ideas crystalized with #AMBAP: A Modest Bitslice Architecture Proposal and the YGREC family was born, with minimalism in mind, allowing me to have a taste of mythical technologies : #YGREC16 - YG's 16bits Relay Electric Computer for relays, #YGRECmos for the 74HC version, #YGREC-ECL for ECL, #YGREC-Si for discrete transistor logic... Again the project bloated (too many features) so I reduced the parts count with an even dumber 8-bits version #YGREC8 (my current focus, sticking to relays for now but wait for the spin-offs)
The YGREC provided me with a totally new perspective, more insight and added new rules to my CPU design play book. The underlying principles (laid out in AMBAP) are finding direct applications in the reboot of F-CPU, as the FC1, which is a cluster of "globules" (modified YGREC cores). The circle is closed now, I'm looking again at the F-CPU and I cover a wide range of applications, from 8 to 64+ bits, and certain projects interact with my professional work such as #WizYasep
I'm happy I succeeded (mostly thanks to HaD) in escaping the "software trap" by going "back to the roots of computer design", I learn so much and I reinvest the knowledge, develop new techniques (the invention of balanced control trees is still amazing me) and writing VHDL code will be a breeze. However the real difficulty is everything around the CPU core : how do you control, drive it, feed it with data, debug, create code, etc. I address these with separate projects such as #HTTaP but making an ecosystem around a processor is much more work than drafting a CPU core on a sheet of paper.
"none of these projects is finished. Why? After so many years working on CPUs, no one is finished?" Because apparently I'm more of a "researcher" type. The most advanced work is the YASEP (see http://news.yasep.org/). I have implemented and "finished" a few things, often mostly because they were pretty dumb OR because someone paid for it (like : artistic projects). The rest : I play with an idea, explore, learn, discover and get disturbed/interrupted by either a new better idea (you know, when you explore something deeply, you gain insight and find what assertions and assumptions were false) or (worse) work. Internal and external influences keep disrupting me, but also, I easily get bored once I think I've covered a subject. However, with time, I've covered a pretty wide range of subjects and creating new things is faster and easier. With my new workshop, it's even more comfortable :-)
"You have great knowledge and a lot of ideas about CPUs architectures." This in itself is something else that I want to cover through my writings. What point is there to learn all those things if I can't transmit them ? I consider writing many articles about these subjects but it requires yet another project. Oh well, see #French articles (some under Creative Commons) (and I haven't even scratched the surface about CPU design). Or "maybe" a book.
Damn.
"I really hope that you can show to us soon a finished project, a great project, with all this knowledge. I will be very happy to discover it." Me too, as you can imagine ! If YGREC8 (or any other) springs to life, I intend to tour DIY places (maybe even sell kits and develop #Grimoire ) and inspire people to do the same. Because it's just so awesome !
Contact me if you have any other questions.
Nice, thanks for Malleo, Yann. I feel an new project coming on lol.
Hey Yann, thanks for the follow and like of the Uglytech relay :-)
Thank YOU for showing kids how easy it is to do :-)
I even found a use for an old corroded fishing weight Lol
Bonjour Yann - Merci pour le suivi de mon nouveau projet #ALithiumIonBatteryManagement Sytsem - A+ - Michel
Merci Yann. Impressionné par tant de belles bidouilles ( au sens noble bien sûr )
De rien :-) bienvenue parmi les bidouilleurs !
You don't need to thank me everytime I click on something :-D
Thanks for following my project: #$1/W True MPPT.
I enjoy your posts tremendously btw, keep up the good work.
Awwww thanks ! I'm happy that I can do things that are interesting, fun and useful :-)
Thank you back :-) You're doing some interesting stuff !
And thanks again Yann for skulling my #Hackaday Stats!
The truth comes out! Professor.Jez and Yann Guidon are one and the same!
ROFL. Now we're going to have to get a selfie just to disprove this. XD
Hey there Yann. I've been trying to figure out who left us a $kull I cannot account for, and I think it was you. :-)
Thanks for the support, buddy!
Bonjour Yann - Thanks a lot for following #YasK - Yet another small Kernel - Merci de suivre mon projet #YasK - Yet another small Kernel. Ce bout de noyau modeste et génial est dans tous mes project micro depuis 5 ans. Cordialement - Michel
Thanks for following my electroadhesive project! If you have any questions or suggestions, let me know!
Thanks for the skull & follow on the Diode Clock! I just found out about this site - looking forward to exploring your projects. Working on a video and new log now...
Thanks for joining us and sharing your hacks ! I'm looking forward to even more eye-popping designs, they keep me on the edge and motivate me to do even better !
Hey, thanks for liking the Dingo Console! Something like that isn't easy, and i needed the support.
It's funny how, once again, I wish the F-CPU was working :-D it would have been a good fit for your project :-)
For now, you have a lot to do with FPGA. I'll be watching !
I took a look at the F-CPU once, and I gotta say I'd choose that in a heartbeat. But I guess a P3 is good too.
You're welcome ! we share goals and hopefully one day you'll use the YASEP or the F-CPU ?
F-CPU is still a thing? I remember that from years ago. I remember proposing using a bitmap to describe an arbitrary logic function (inspired by Amiga's blitter, actually), instead of having separate AND, OR, XOR, etc. instructions. :) I wonder what happened to that?
Well... this reminds me things !!!
The ROP2 has been a feature of F-CPU and YASEP since then :-)
Woot! Thanks for the buck, yo! Looks like you've got quite a few coming, yourself!
well that's springtime, buck mating season, right ?
So I changed my avatar to be more in the mood
Thanks for another follow, Yann! (This is my threshold for gratitiudinal-feed-filling, from now on expect '++' or '+=n' located here ;)
Hello Yann...
Why so many CPU projects? I really don't understand. I've seen 13 CPU projects from you on hackaday. That's huge! And I'm pretty sure that there are some other projects missing on hackaday.
YGREC-ECL ; YGREC8 ; YGRECmos ; Discrete YASEP ; AMBAP ; SPDT16 ; YASEP ; YGREC-РЭС15-bis; YGREC-Si; YGREC16; FCPU (FC0 & FC1); YASEP ; microYasep...
It's really difficult to understand the organisation of all these projects, and therefore it is difficult to understand all your work.
Furtheremore, it seems that none of these projects is finished. Why? After so many years working on CPUs, no one is finished?
I think that you should concentrate on only one project, and finish it before starting a new one, and avoid dispersing with so many projects.
Finishing one project is a great reward... at least from my point of view. It's only an advice, you do what you want.
You have great knowledge and a lot of ideas about CPUs architectures. I really hope that you can show to us soon a finished project, a great project, with all this knowledge. I will be very happy to discover it.