The eBay listing for these boards should now offer international shipping. I spent about two hours with eBay support, and they were able to get it working.
Personally, I gain a huge amount from the walkthroughs of your Fusion skills James - especially from your analytical explanations of the thought process behind your approach to the design and modelling problems. This aspect plus the huge variety of engineering, electronics and software topics is the USP that makes your channel so unique and unequalled - please let it continue!
For just a quick explanation of your modeling process, this may actually have been one of the most informative videos I have seen. I think I just picked up a ton of tips to improve my projects.
Very cool.. most folks would have just cut the end off of an old answering machine power supply and called it a day. I like the fact you took the time to engineer a proper power supply explicitly suited for the vintage batteries ..perfection
Personally, I really like the CAD explanations. I get that you're not specifically a CAD tutorial channel, but I'll happily take however much CAD stuff you want to put in!
James, the Fusion 360 tutorials is one of the main reasons I watch your videos. I've learned so many useful tricks that no else explains. You teach Fusion using real projects and solve real problems. Keep them part of the videos...
Can we just take a moment to appreciate how clean the design/function of that 3d print is? Feels like a masterclass in simplicity meets functionality meets perfect form factor Also, want to echo the commentary from others that seeing more of the modeling process is super helpful
I've not used this particular LDO (although I've used many others), but many are quite sensitive to the output impedance, i.e. they need the output capacitor to be physically located close to the output pin in order to avoid trace inductance reacting in series with the capacitor. Your design is "neat" but places the caps at a distance from the IC (compare to the suggested layouts in the TI datasheet). I suggest you test your final PCA for ringing or other nasties in response to step load changes. I'd also strongly suggest conformally coating the circuit, else atmospheric contaminants will affect the output voltage.
To avoid polarity issues, you can use a P-MOS as polarity protection. You'll probably lose a tiny bit of dropout but it should be worth the added safety.
always love the detail you go to in your videos and the fact that you dont skip any steps. always nice to see a purposeful project from start to finish. Solid info, thank you.
If there was a neat-o-meter, your projects would bend the needle. Your command of CAD is also always a pleasure to watch. Nice to see KiCad get used! It's really great software.
I like the quick overviews of modelling. I always get ideas from workflows and thinking paths of other people. A full modelling videos often get very long and have too many boring routine operations. Giving out main points and tips are something I really like. This video is another reminder of how valuable tool a 3d printer is for fixing stuff. Getting custom parts with pretty accurate dimensions is so helpful and before 3d printers it often was a lot of work, like manually filing enclosures (that were paint to repeat if the fit was not perfect).
@@Clough42 I've noticed that but still I often surprise myself when I first think of the hard way and then note "I can print that", especially when it need something like printing a part to just help out the other things.
23:25 - It's the fascinating, creative and ingenuity of the solutions they came up with. Like a CRT TV. Despite modern TVs are based on major scientific advancements compared to CRTs, one can help but to feel like the old CRTs is a way more impressive achievement, both as a invention and the practical workings. An electron beam shooting out, bend by magnetic fields, hitting a phosphor coating in various intensities. Amazing.
Considering that the first televisions were mechanicak (for the display), you are quite correct about how far technology can advance in just a short time.
Great video! Thank you for the quick fusion highlights, they flowed well and the info/time ratio was perfect 🎉 The pcb design and test equipment demo was excellent too along with the quiescent current calculations. Thank you for the effort and for sharing the story 🥳
Great video, as always! I for one really like watching the CAD work! I'd say that I'm mid tier to fairly advanced when it comes to the Design portion of Fusion, and while this particular CAD work is fairly elemental to me, I _still_ enjoy watching it. It's really interesting to see how other ppl approach a modeling task and how they solve different problems. There is often something to be learned, and if not, it's still entertaining (not in the ha-ha nor facepalm way). Tip: If you use a center point rectangle in the first sketch, the origin will be in the center of the box, and you wont have to create a mid plane later on. BTW, your videos are always the first video I click on when I see it in my feed. Keep it up!
Oh, excellent tip on the origin. I hadn't thought about that. On complex projects, I think a lot about setting up orthogonal sketches and mapping out the overall structure. With something this simple, I usually just drop a rectangle and dive in, but that would have made things a lot easier.
I do love your F360 walkthroughs. I always pick up something I would have done differently(not as easily) prior to watching you. Love it! More please. 😎
Protip: Replace the rubber bands on your insert press with "latex free" ones. I have found they tend to degrade much more slowly on exposure to the environment (no idea whether it's UV, heat, trace ozone, just oxygen or some combination) compared to "regular" rubber bands, which tend to dry out and crack with distressing speed when used in this way.
I like the Fusion modeling stuff, but I think what you showed here was the vast majority of what I want to see from those videos anyhow, and it was nicely condensed down.
James is as usual the perfectionist 🏆 I would've bodged together something with LM317, rewired the switch and hot glued everything together at the back 🤣
@Clough42 James, I would definitely be interested in the Fusion step-through for the design of this piece. Your methods are excellent and easy to learn from.
I keep seeing more and more useful stuff on your channel, so you just earned my support on Patreon. Thank you and I look forward to learning more from you.
"There's no reason to expect anything to be wrong with this" haha - how many times engineers have said this before disaster :) All jokes aside, you made a fantastic solution.
really enjoyed the quick fusion 360 tips.. Would love to see them in more videos. as you say the whole modeling process is a long video but these are great to get the point....
Hi James, just a thought, there must be other vintage kit out there with what are nowadays weird and wonderful voltage requirements. Maybe your viewers could chime in. There may be a market for a variable or pre-selectable multi-voltage variant of this handy device. Kudos for keeping the Federal up and running, it would be sad to lose these interesting examples of vintage test gear.
Rigol makes nice test equipment for the hobbiest don't they. I really like your Fusion 360 videos. I get why they may not be popular but your Fusion 360 videos are better than most of the videos on YT. Also, the box design made me think about creating something for the old battery operated farm radios from the 40's
No need to go back and show the modeling process for this box but I do really like your modeling segments. I learn a lot so please consider keeping them in for future videos.
I appreciate that you didn't just cut the terminals off and solder in a wall wart 5.4V power supply like most ppl would've done. Really enjoyed this, thank you for uploading! 👍👍
Very interesting. All this stuff is over my head as far as understanding goes. The way you present it though is kind of making it easy to understand you have a way about you in your delivery that works well for me. Thank you I'd also like to thank you for your work at the summer bash appreciate the time you put in and as always you did a wonderful job. GOOD DAYS .KIMBER
With LM317 there is another issue: Its internal circuitry is supplied from the difference between the input and output. So the current consumption of that internal circuitry needs to be drawn from the output as a minimum load, otherwise it will loose regulation and put higher voltage on the output. The datasheet specifies this minimum load, it uses to be in the 5..10mA ballpark. This minimum load requirement and the minimum drop of about 1.5..2V is the price to pay to make a 3-pin adjustable regulator feasible.
Seeing how casually James whipped up that circuit board, it really does give me a push to just give circuit board creation a try. I can't help but think if this guy finds it easy and is sort of a generalist maker who I would have assumed just wouldn't have wanted to bother picking up something I previously just sort of held in my mind as a huuuuge undertaking, surely I can get some stuff done with my relatively similar projects in terms of complexity. It's at least approachable. Seperately, a lot of things are getting worse in the world, but I love the fact some dude can now make a circuit board design, something you'd have to be a multimillion dollar company to do before from the comfort of his home office with a cheap service to fix his own stuff. It's too bad modern items are purposefully built to disallow that so much.
Making pcbs is pretty straight forward if you understand the electronics already. Plan on having a few wrong ones before you get any board right though lol. Also it might be easiest to start with getting the boards made and soldering them up yourself first. Do get the stencil though, that's worth it for surface mount. Ordering PCB assembly is another step on top. Not particularly hard or anything but if you're just starting smaller steps might be better. Jlcpcb are pretty good, they have a "basic library" of parts for assembly and if you stick within that you can actually get boards assembled with components really pretty cheap when you get to that level.
Just subscribed to your Patreon. I’ve been watching your videos for a bit now. Between you, AVE, and ThisoldTony I’ve learned more than my pride will let me admit.
That's an interesting comment. I guess I would never see learning new things from someone else as a hit to my pride. I have already learned a couple of new things just reading through the comments on this video this morning.
Nice project. Been looking for a boost converter with similar idle current under no load to switch my 9V battery flukes over to lithium. I have an Itec DC load with similar annoying screw terminals so I designed a small adapter PCB that slips over the screw terminals and adds two banana receptacles spaced .75" apart. (for double banana plugs). Post your terminal spacing, if it's the same I can send you a board. You will have to lathe out your own brass receptacles.
Instruments with obnoxious or obnoxiously spaced terminals: I've had this problem several times in the past. I'd cut out a piece of 1/8" Plexiglas big enough to cover the existing terminals, plus space for a pair of 5-way binding posts on 3/4 centers, then wire ring terminals on flying leads to the bottoms of the banana jacks, and screw the whole thing to the instrument with the original obnoxious binding post caps. Works a treat. Obviously these days in the world of easy PC boards, you could make a little PC board, but would want to use thicker than normal stock for physical stiffness. Or you could 3D print a thing and mount a preassembled 3/4" spacing dual banana jack to it (if they still make those). If the machine can deal with multiple megaohms I might prefer the piece of plex to some hunk of possibly slightly conductive printed plastic.
in the name of preservation I'd highly recommend using keyed headers on the PCB, that way you get it right once, and then future-you (or future inheritor) can't accidentally screw it up. if the voltage drop is acceptable and the device is rare enough to justify the effort, might even be worth splicing a diode in series with the wire going to the output connector as an extra layer of protection. also, might be worth checking the output voltage with an oscilloscope when you enter the dropout zone, from the meters it looks like it was jumping around a bit, the voltage regulation is probably unstable in that region. it would be good to verify the frequency and magnitude of those oscillations, and if they seem problematic you either add an under-voltage lockout (UVLO) circuit to the input to cut off power once the voltage dips too low, or if they're minor enough to mitigate, something like a pi filter to the output to prevent the noise from reaching the device. unfortunately, looks like the chip's Power Good output is not suitable for detecting the dropout condition, it's only meant to be used to signal when startup is complete, otherwise you could use that output to drive a MOSFET on the output also: pointless but cute idea: bin the PCBs by quiescent current and dropout voltage, there will be some amount of variation between them you could exploit to get that extra tiny fraction of performance
I retired from the engineering department at a local university. We had instruments that used mercury cells/batteries. When health and safety came around we had to hide the mercury cells. I could tell lots of stories about mercury. We had a kepro pcb prototype system, we would sensitize our copper clad boards and then photo etch the pcb's. We used Cadence Orcad, for us, it was cheap. If I wanted to make a box like yours, it would probably be broke up sheet metal, welded plates, or machined from a block of aluminum. Eventually we got a cnc system to route the boards and do the drilling. I'm responding to illustrate how the world has changed. It is so cheap to send the cad files out and get the boards mailed back quickly. I'm impressed. Jim
That's very cool. I've used pre-sensitized copper clad boards and spray-on photoresist with ferric chloride. I was just getting ready to set up a cupric chloride etching bath when the cheap PCB manufacturing services started coming on-line. The solder mask you get with the commercial processes is the biggest win.
James plus one for the F 360 Tutorials please. I have always found your snippets to be the easiest to follow and the most germane to the work flows I use.
Loved the video, i too follow you for fusion and 3d printing things among others. Speaking from pure jealousy only - your bench equipment alone is worth almost $2000 - but surprisingly affordable for such usable gear
this is a really nice design, if I read the data sheet right these can be built to from about 12.5 to 17.5 volts. with a few good parametric prints, you could make this into a framework and have a print your own battery replacement standard. you would need to keep multiple output options on stock though. but you could corner the market on old battery replacement.
Thanks, James. A request for your next Mercury Battery Replacement: while there are work-arounds available in the form of metal cell adapters, it would really be nice not to have to use extra pieces to provide power to my vintage (original owner) Nikon F Photomic Ftn finder (requires 2, 1.35V PX625 cells). This should challenge your micro circuitry abilities 😊
My first thought was that they might have put that backwards board at the 10th spot for easy counting when you have a full reel or parts or something but I think that one was around 17th so that doesn't make sense. Another thought was that maybe that board did not pass their continuity testing but you still get what you ordered so they are just letting you know. Or maybe the parts were in a box and they just didn't care. But places like PCB houses are usually very conscious of things like this. Attention to detail is important in this world.
Hey there, one side thing i do on the side is modernize old equipment (data logging, battery replacement, communication modernization, exc) and this is basically how we do it. If the device is sensitive we use a low QI LDO, if its not very sensitive we will use a buck regulator with a following linear regulator, or if its not-sensitive we just use a buck. For power we either use lithium AA batteries or 18650 cells. if the back was externally accessible i would have thrown in a switch and a battery indicator, however nothing here took from the original design and you can't argue with that! keep it up ... except using alligator clips directly on the threads of the load ... that hurt
Yeah. I need a better solution for connecting the load. I did some searching, expecting to find some purpose-built leads, but I must not be using the right keywords.
Always wondered why you don't use Kicad, but was too scared to ask, fearing the irascible answer. I'm a big fan and user of Kicad, so kudo's! With the help of CERN, they've come a long way. Additionally, I always love your Fusion tutorials. I've used 2D CAD all my life, but I'm extremely F360 challenged, to my great frustration. It helps watching you, and yes, I'm very jealous. Nice battery solution BTW. I was one of the whiners about alkalines :-)
I started with the free version of Eagle, but the license doesn't permit commercial use, which is why I ended up using CircuitMaker. CircuitMaker is great, but Altium dumbed down the library management, which really wrecks the workflow.
Thanks for showing the Fusion highlights, those are always a treat! Can I find some info about your education and work experience? You're combining pretty much all the areas that I love to tinker with but I'm just going about this as a hobby whereas it seems like you've actually been able to work with these things professionally.
Thanks! Watched it right away. Sounds like I'm on a very similar track to yours! I would love to somehow get the opportunity you had at the model shop. It's a difficult combination to achieve as a software developer though. Not a lot of jobs out there where those two industries meet and certainly not where is allowed to tinker the side. How long ago was that?
I just ordered a board. I don't have any need right now for 5.4V, but I figure I can always change a resistor value for another voltage I may need. At least the tiny WSON package will already be mounted on the board.
For faster (electronics) prototyping, you can get breakout boards that convert SMT layouts to DIP. I haven't used them, but Proto Advantage sells a SON-6 to DIP10 breakout that should work with the TPS7A25's WSON-6 package, it's their IPC0165: SON-6 to DIP-10 SMT Adapter.
Nice projet! On battery device, always use protective device for limiting current at the input, a PTC of 100 to 300mA are good, a "0ZCK0010FF2G" or "0805L010YR" is 100ma 15v. In case of static discharge kill the regulator, the ptc device limit the current and make the fail much safer....
I was hoping that you would go so far as to make new terminals for the existing battery plug instead of using that old bit of board from the old battery.
I thought the CAD sequence was a nice level of detail, it gave tips for the parts that weren't obvious but skipped a lot of the boring parts. I'd love to see that again in future videos When you make spring tabs, does it matter that they will bend "across the grain" so they're pulling against inter-layer adhesion? I would have thought you have to make springy things bend *along* layers? I've never 3D printed anything
For the battery holder platform in the box you made. Would it be better to make a thick perimeter of the platform or possibly stakes to hold the threaded inserts? The way I see it, why not just take advantage of the battery holders rigidness and use it as the top? Maybe brace the corners if that is a weakness. Am I missing something about this that it wouldn't work?
For those that don't have the free time to do this you can do what I did for my old gate opener and use a 3s lipo RC battery and a combo voltage regulator with low voltage cutoff, this cost about $30 on amazon and I had it in hand the next day.
That's a perfectly acceptable solution, but a rather short video. Given there were original 4 NiCads (~4.8v) the voltage isn't all that critical anyway.
The eBay listing for these boards should now offer international shipping. I spent about two hours with eBay support, and they were able to get it working.
Personally, I gain a huge amount from the walkthroughs of your Fusion skills James - especially from your analytical explanations of the thought process behind your approach to the design and modelling problems.
This aspect plus the huge variety of engineering, electronics and software topics is the USP that makes your channel so unique and unequalled - please let it continue!
For just a quick explanation of your modeling process, this may actually have been one of the most informative videos I have seen. I think I just picked up a ton of tips to improve my projects.
Agreed. And you asked us to comment if we'd like to see more of your Fusion360 modeling process in your projects: yes, please!
You said chaotic neutral .. and used it correctly. Well done good sir.
Chaotic Neutral is best neutral
Very cool.. most folks would have just cut the end off of an old answering machine power supply and called it a day. I like the fact you took the time to engineer a proper power supply explicitly suited for the vintage batteries ..perfection
Personally, I really like the CAD explanations. I get that you're not specifically a CAD tutorial channel, but I'll happily take however much CAD stuff you want to put in!
James, the Fusion 360 tutorials is one of the main reasons I watch your videos. I've learned so many useful tricks that no else explains. You teach Fusion using real projects and solve real problems. Keep them part of the videos...
Can we just take a moment to appreciate how clean the design/function of that 3d print is? Feels like a masterclass in simplicity meets functionality meets perfect form factor
Also, want to echo the commentary from others that seeing more of the modeling process is super helpful
I've not used this particular LDO (although I've used many others), but many are quite sensitive to the output impedance, i.e. they need the output capacitor to be physically located close to the output pin in order to avoid trace inductance reacting in series with the capacitor. Your design is "neat" but places the caps at a distance from the IC (compare to the suggested layouts in the TI datasheet). I suggest you test your final PCA for ringing or other nasties in response to step load changes.
I'd also strongly suggest conformally coating the circuit, else atmospheric contaminants will affect the output voltage.
So slather in hot glue, got it :)
To avoid polarity issues, you can use a P-MOS as polarity protection. You'll probably lose a tiny bit of dropout but it should be worth the added safety.
That's not a bad idea.
always love the detail you go to in your videos and the fact that you dont skip any steps. always nice to see a purposeful project from start to finish. Solid info, thank you.
If there was a neat-o-meter, your projects would bend the needle. Your command of CAD is also always a pleasure to watch. Nice to see KiCad get used! It's really great software.
For me, the Fusion 360 work is my favorite part of your channel!
I like the quick overviews of modelling. I always get ideas from workflows and thinking paths of other people. A full modelling videos often get very long and have too many boring routine operations. Giving out main points and tips are something I really like.
This video is another reminder of how valuable tool a 3d printer is for fixing stuff. Getting custom parts with pretty accurate dimensions is so helpful and before 3d printers it often was a lot of work, like manually filing enclosures (that were paint to repeat if the fit was not perfect).
Once you have a 3D printer (and the CAD skills to design what you need) the applications find themselves.
@@Clough42 I've noticed that but still I often surprise myself when I first think of the hard way and then note "I can print that", especially when it need something like printing a part to just help out the other things.
23:25 - It's the fascinating, creative and ingenuity of the solutions they came up with. Like a CRT TV. Despite modern TVs are based on major scientific advancements compared to CRTs, one can help but to feel like the old CRTs is a way more impressive achievement, both as a invention and the practical workings.
An electron beam shooting out, bend by magnetic fields, hitting a phosphor coating in various intensities. Amazing.
Considering that the first televisions were mechanicak (for the display), you are quite correct about how far technology can advance in just a short time.
Great video! Thank you for the quick fusion highlights, they flowed well and the info/time ratio was perfect 🎉
The pcb design and test equipment demo was excellent too along with the quiescent current calculations. Thank you for the effort and for sharing the story 🥳
Voting for more Fusion details. I learn something new from you in ever video. Thanks for the hard work and well made videos!
Great video, as always! I for one really like watching the CAD work! I'd say that I'm mid tier to fairly advanced when it comes to the Design portion of Fusion, and while this particular CAD work is fairly elemental to me, I _still_ enjoy watching it. It's really interesting to see how other ppl approach a modeling task and how they solve different problems. There is often something to be learned, and if not, it's still entertaining (not in the ha-ha nor facepalm way).
Tip: If you use a center point rectangle in the first sketch, the origin will be in the center of the box, and you wont have to create a mid plane later on.
BTW, your videos are always the first video I click on when I see it in my feed. Keep it up!
Oh, excellent tip on the origin. I hadn't thought about that. On complex projects, I think a lot about setting up orthogonal sketches and mapping out the overall structure. With something this simple, I usually just drop a rectangle and dive in, but that would have made things a lot easier.
I put the center point rectangle on the tool bar since that's the only one I tend to use.
I do love your F360 walkthroughs. I always pick up something I would have done differently(not as easily) prior to watching you. Love it! More please. 😎
Thanks for filing this TPS Report, James.
Iiiii'm gonna have to go ahead and give it a thumbs up.
I do watch your Fusion content as I always learn something new. Yah is James.
Protip: Replace the rubber bands on your insert press with "latex free" ones. I have found they tend to degrade much more slowly on exposure to the environment (no idea whether it's UV, heat, trace ozone, just oxygen or some combination) compared to "regular" rubber bands, which tend to dry out and crack with distressing speed when used in this way.
I find when you need a specific long lasting elastic band with repeatable stretch, o rings work well and last a long time.
I like the Fusion modeling stuff, but I think what you showed here was the vast majority of what I want to see from those videos anyhow, and it was nicely condensed down.
Thanks! I've been working on finding the right balance. It's easy to get bogged down.
James is as usual the perfectionist 🏆 I would've bodged together something with LM317, rewired the switch and hot glued everything together at the back 🤣
@Clough42 James, I would definitely be interested in the Fusion step-through for the design of this piece. Your methods are excellent and easy to learn from.
I learn so much from your modeling sections. Would love to see some more in depth videos on the subject.
I think these kind of quick modeling rundowns (tips) are a perfect middle ground.
I keep seeing more and more useful stuff on your channel, so you just earned my support on Patreon. Thank you and I look forward to learning more from you.
I am jealous of your Fusion 360 skills. You could do a channel just for that.
Great work! Very useful analysis of the Fusion 360 process. Thanks!
"There's no reason to expect anything to be wrong with this" haha - how many times engineers have said this before disaster :)
All jokes aside, you made a fantastic solution.
Your content is always super interesting and keeps getting better and better.
really enjoyed the quick fusion 360 tips.. Would love to see them in more videos.
as you say the whole modeling process is a long video but these are great to get the point....
You give the best fusion 360 tutorials
Hi James, just a thought, there must be other vintage kit out there with what are nowadays weird and wonderful voltage requirements. Maybe your viewers could chime in. There may be a market for a variable or pre-selectable multi-voltage variant of this handy device. Kudos for keeping the Federal up and running, it would be sad to lose these interesting examples of vintage test gear.
Thanks James! I'll never need this but I much appreciate tagging along:)
Rigol makes nice test equipment for the hobbiest don't they. I really like your Fusion 360 videos. I get why they may not be popular but your Fusion 360 videos are better than most of the videos on YT. Also, the box design made me think about creating something for the old battery operated farm radios from the 40's
I look forward to watching your videos every Saturday. Keep up the good content!
No need to go back and show the modeling process for this box but I do really like your modeling segments. I learn a lot so please consider keeping them in for future videos.
I appreciate that you didn't just cut the terminals off and solder in a wall wart 5.4V power supply like most ppl would've done. Really enjoyed this, thank you for uploading! 👍👍
Very interesting. All this stuff is over my head as far as understanding goes. The way you present it though is kind of making it easy to understand you have a way about you in your delivery that works well for me. Thank you
I'd also like to thank you for your work at the summer bash appreciate the time you put in and as always you did a wonderful job. GOOD DAYS .KIMBER
TIL about the shell command. Thanks James!
With LM317 there is another issue: Its internal circuitry is supplied from the difference between the input and output. So the current consumption of that internal circuitry needs to be drawn from the output as a minimum load, otherwise it will loose regulation and put higher voltage on the output. The datasheet specifies this minimum load, it uses to be in the 5..10mA ballpark. This minimum load requirement and the minimum drop of about 1.5..2V is the price to pay to make a 3-pin adjustable regulator feasible.
I always learn something from your Fusion 360 demos. Thanks so much.
As usual very good work! Thanks again James,
I'm one of your viewers who love the Fusion 360 tutorials.
I would LOVE to watch and learn Fusion 360 from some videos you make. i like the way you work. Great job mate.
Seeing how casually James whipped up that circuit board, it really does give me a push to just give circuit board creation a try. I can't help but think if this guy finds it easy and is sort of a generalist maker who I would have assumed just wouldn't have wanted to bother picking up something I previously just sort of held in my mind as a huuuuge undertaking, surely I can get some stuff done with my relatively similar projects in terms of complexity. It's at least approachable.
Seperately, a lot of things are getting worse in the world, but I love the fact some dude can now make a circuit board design, something you'd have to be a multimillion dollar company to do before from the comfort of his home office with a cheap service to fix his own stuff. It's too bad modern items are purposefully built to disallow that so much.
Making pcbs is pretty straight forward if you understand the electronics already. Plan on having a few wrong ones before you get any board right though lol. Also it might be easiest to start with getting the boards made and soldering them up yourself first. Do get the stencil though, that's worth it for surface mount. Ordering PCB assembly is another step on top. Not particularly hard or anything but if you're just starting smaller steps might be better.
Jlcpcb are pretty good, they have a "basic library" of parts for assembly and if you stick within that you can actually get boards assembled with components really pretty cheap when you get to that level.
Now that's a really well thought out solution. I may need to order one of your boards for mine.
Just subscribed to your Patreon. I’ve been watching your videos for a bit now. Between you, AVE, and ThisoldTony I’ve learned more than my pride will let me admit.
That's an interesting comment. I guess I would never see learning new things from someone else as a hit to my pride. I have already learned a couple of new things just reading through the comments on this video this morning.
Excellent design! Enjoyed the hell out of it.
We've come a long way from the 1.5+ volt drop, 5V linear regulators.
21:51 I can't speak for all your viewers, but it would be kinda neat to see how tall fingerprint ridges are.
Nice project. Been looking for a boost converter with similar idle current under no load to switch my 9V battery flukes over to lithium. I have an Itec DC load with similar annoying screw terminals so I designed a small adapter PCB that slips over the screw terminals and adds two banana receptacles spaced .75" apart. (for double banana plugs). Post your terminal spacing, if it's the same I can send you a board. You will have to lathe out your own brass receptacles.
Instruments with obnoxious or obnoxiously spaced terminals:
I've had this problem several times in the past. I'd cut out a piece of 1/8" Plexiglas big enough to cover the existing terminals, plus space for a pair of 5-way binding posts on 3/4 centers, then wire ring terminals on flying leads to the bottoms of the banana jacks, and screw the whole thing to the instrument with the original obnoxious binding post caps. Works a treat.
Obviously these days in the world of easy PC boards, you could make a little PC board, but would want to use thicker than normal stock for physical stiffness. Or you could 3D print a thing and mount a preassembled 3/4" spacing dual banana jack to it (if they still make those). If the machine can deal with multiple megaohms I might prefer the piece of plex to some hunk of possibly slightly conductive printed plastic.
in the name of preservation I'd highly recommend using keyed headers on the PCB, that way you get it right once, and then future-you (or future inheritor) can't accidentally screw it up. if the voltage drop is acceptable and the device is rare enough to justify the effort, might even be worth splicing a diode in series with the wire going to the output connector as an extra layer of protection.
also, might be worth checking the output voltage with an oscilloscope when you enter the dropout zone, from the meters it looks like it was jumping around a bit, the voltage regulation is probably unstable in that region. it would be good to verify the frequency and magnitude of those oscillations, and if they seem problematic you either add an under-voltage lockout (UVLO) circuit to the input to cut off power once the voltage dips too low, or if they're minor enough to mitigate, something like a pi filter to the output to prevent the noise from reaching the device. unfortunately, looks like the chip's Power Good output is not suitable for detecting the dropout condition, it's only meant to be used to signal when startup is complete, otherwise you could use that output to drive a MOSFET on the output
also: pointless but cute idea: bin the PCBs by quiescent current and dropout voltage, there will be some amount of variation between them you could exploit to get that extra tiny fraction of performance
Very nice work, you checked all the boxes for function,fit and finish.
Watching you model in Fusion 360 is really helpful for me - I’d be happy to watch a. Full video!
I retired from the engineering department at a local university. We had instruments that used mercury cells/batteries. When health and safety came around we had to hide the mercury cells. I could tell lots of stories about mercury.
We had a kepro pcb prototype system, we would sensitize our copper clad boards and then photo etch the pcb's. We used Cadence Orcad, for us, it was cheap. If I wanted to make a box like yours, it would probably be broke up sheet metal, welded plates, or machined from a block of aluminum. Eventually we got a cnc system to route the boards and do the drilling.
I'm responding to illustrate how the world has changed. It is so cheap to send the cad files out and get the boards mailed back quickly.
I'm impressed.
Jim
That's very cool. I've used pre-sensitized copper clad boards and spray-on photoresist with ferric chloride. I was just getting ready to set up a cupric chloride etching bath when the cheap PCB manufacturing services started coming on-line. The solder mask you get with the commercial processes is the biggest win.
thanks for showing your CAD workflow. Always good to see how other people do it, considering there are many ways to achieve the end result (18
Lighting in the background at the end: machining and dance party. Wild weekends.
Yuchol Kim sent me that disco light as a joke. I used it in a video as a joke, and I kind of liked it. :)
Really enjoyed the presentation. Many thanks.
James plus one for the F 360 Tutorials please. I have always found your snippets to be the easiest to follow and the most germane to the work flows I use.
Loved the video, i too follow you for fusion and 3d printing things among others. Speaking from pure jealousy only - your bench equipment alone is worth almost $2000 - but surprisingly affordable for such usable gear
this is a really nice design, if I read the data sheet right these can be built to from about 12.5 to 17.5 volts. with a few good parametric prints, you could make this into a framework and have a print your own battery replacement standard. you would need to keep multiple output options on stock though. but you could corner the market on old battery replacement.
I was surprised there wasn't already something out there. It will be interesting to see if there's much demand.
Thank you for showing the Fusion 360 steps, very good tips for a hobbyist!!
Very neat work. Enjoyable to watch.
Thanks, James. A request for your next Mercury Battery Replacement: while there are work-arounds available in the form of metal cell adapters, it would really be nice not to have to use extra pieces to provide power to my vintage (original owner) Nikon F Photomic Ftn finder (requires 2, 1.35V PX625 cells). This should challenge your micro circuitry abilities 😊
My first thought was that they might have put that backwards board at the 10th spot for easy counting when you have a full reel or parts or something but I think that one was around 17th so that doesn't make sense. Another thought was that maybe that board did not pass their continuity testing but you still get what you ordered so they are just letting you know. Or maybe the parts were in a box and they just didn't care. But places like PCB houses are usually very conscious of things like this. Attention to detail is important in this world.
Elegant, James, elegant. 👍
Hey there, one side thing i do on the side is modernize old equipment (data logging, battery replacement, communication modernization, exc) and this is basically how we do it. If the device is sensitive we use a low QI LDO, if its not very sensitive we will use a buck regulator with a following linear regulator, or if its not-sensitive we just use a buck. For power we either use lithium AA batteries or 18650 cells.
if the back was externally accessible i would have thrown in a switch and a battery indicator, however nothing here took from the original design and you can't argue with that!
keep it up ... except using alligator clips directly on the threads of the load ... that hurt
Yeah. I need a better solution for connecting the load. I did some searching, expecting to find some purpose-built leads, but I must not be using the right keywords.
I'm sure it's niche content, but I always learn something about Fusion360 when you do the design segments!
Always wondered why you don't use Kicad, but was too scared to ask, fearing the irascible answer. I'm a big fan and user of Kicad, so kudo's! With the help of CERN, they've come a long way. Additionally, I always love your Fusion tutorials. I've used 2D CAD all my life, but I'm extremely F360 challenged, to my great frustration. It helps watching you, and yes, I'm very jealous. Nice battery solution BTW. I was one of the whiners about alkalines :-)
I started with the free version of Eagle, but the license doesn't permit commercial use, which is why I ended up using CircuitMaker. CircuitMaker is great, but Altium dumbed down the library management, which really wrecks the workflow.
Three lithium cells in series gives 5.4 volts, perfect, done.
Thanks for showing the Fusion highlights, those are always a treat!
Can I find some info about your education and work experience? You're combining pretty much all the areas that I love to tinker with but I'm just going about this as a hobby whereas it seems like you've actually been able to work with these things professionally.
I did a Q&A a couple of years back with some of this info.
Thanks! Watched it right away. Sounds like I'm on a very similar track to yours!
I would love to somehow get the opportunity you had at the model shop. It's a difficult combination to achieve as a software developer though. Not a lot of jobs out there where those two industries meet and certainly not where is allowed to tinker the side.
How long ago was that?
I like the modeling tips James, although im using solidworks it helps me overcome potential hurdles
I just ordered a board. I don't have any need right now for 5.4V, but I figure I can always change a resistor value for another voltage I may need. At least the tiny WSON package will already be mounted on the board.
Enjoyed…thank you for sharing…awesome discussion
Silly question, why not 3 Li batteries?
For faster (electronics) prototyping, you can get breakout boards that convert SMT layouts to DIP. I haven't used them, but Proto Advantage sells a SON-6 to DIP10 breakout that should work with the TPS7A25's WSON-6 package, it's their IPC0165: SON-6 to DIP-10 SMT Adapter.
Nice projet!
On battery device, always use protective device for limiting current at the input, a PTC of 100 to 300mA are good, a "0ZCK0010FF2G" or "0805L010YR" is 100ma 15v.
In case of static discharge kill the regulator, the ptc device limit the current and make the fail much safer....
TBH I'd watch unedited modeling footage. Seeing how someone else approaches different types of problems is incredibly handy.
This is something I've considered. I wonder if anyone else would watch it...or if you would keep watching once you discovered how chaotic it is. :)
Just learned more about confusion 360 in 20 minutes than my collage professor was able to teach in 2 weeks. Where was this video 4 months ago
I was hoping that you would go so far as to make new terminals for the existing battery plug instead of using that old bit of board from the old battery.
I really like to see your thought process regarding design in Fusion 360.
Nice work. You could of made your model with a hood around the plug so the wire would have to line up to make it only possible to slot in one way. 👍
Nice thorough design, James. P.S. I bought one in case I can use it for the vintage milliohmeter.
I was really looking forward to seeing that new plastic box slide into the original paper box. Sigh.
Same here, and thought that would be a surprise ending as it hadn't been mentioned. I'm guessing the AA battery holder is a tad too wide for the box.
I'm really into the modeling videos!
Overkill, absolutely amazing work man 😂
Overkill is underrated. :)
Hello Clough, I really love using fusion 360 I also made a battery holder for one my transitor radios !
I thought the CAD sequence was a nice level of detail, it gave tips for the parts that weren't obvious but skipped a lot of the boring parts. I'd love to see that again in future videos
When you make spring tabs, does it matter that they will bend "across the grain" so they're pulling against inter-layer adhesion? I would have thought you have to make springy things bend *along* layers? I've never 3D printed anything
For the battery holder platform in the box you made. Would it be better to make a thick perimeter of the platform or possibly stakes to hold the threaded inserts? The way I see it, why not just take advantage of the battery holders rigidness and use it as the top? Maybe brace the corners if that is a weakness. Am I missing something about this that it wouldn't work?
Nicely done!
For those that don't have the free time to do this you can do what I did for my old gate opener and use a 3s lipo RC battery and a combo voltage regulator with low voltage cutoff, this cost about $30 on amazon and I had it in hand the next day.
perfect retrofit exists!
If 4 cells gives 7.23V, then 3 cells give 5.42V. The most obvious solution to get 5.4 volts would be to use 3 cells, not a linear regulator.
That's a perfectly acceptable solution, but a rather short video. Given there were original 4 NiCads (~4.8v) the voltage isn't all that critical anyway.
That would work for a few minutes, but the voltage drops as the battery discharges, dropping below 1.4v per cell toward the end of its useful life.
Thanks!
I wouldn't mind very detailed videos on the CAD work.
It would be kinda cool if you could make a cardstock "box" for the battery pack that looks like the mercury battery packaging.
I'd love more videos of the modeling process