hybridfree/eevblog-posts huggingface dataset:
Seeed PCB Assembly? - Page 1
Forum section: electronics / general

author: phil from seattle
author_rank: Super Contributor
timestamp: January 27, 2021, 08:23:44 pm
content: Anyone using Seeed for PCB assembly? They have some rather large discounts to entice people. I looked at their "library" but it's pretty meager and (relatively) expensive. I wonder how they do with parts from a disti like LCSC?Any feedback would be appreciated.

author: Kasper
author_rank: Frequent Contributor
timestamp: January 29, 2021, 10:32:26 pm
content: I like Seeed, actually have a bookmark from them on my fridge now, it has a quote from Parks and Rec: "Never half-ass 2 things, whole-ass 1 thing" - Ron SwansonI've had a handful of bare boards from them, some metal stencils and maybe some assembly, can't remember. Haven't had any problems with them.They recently launched an interesting sounding new platform to help people launch their products:https://www.seeedstudio.com/fusion-marketplace.html

author: phil from seattle
author_rank: Super Contributor
timestamp: January 29, 2021, 11:07:03 pm
content: Thanks, I have used them for a couple of bare boards, too. They were ok as I recall. Seeed is pushing their (new?) assembly services and I was hoping to hear of other people's experiences. I suspect they are watching the success of JLCPCB and wanting a piece of that market.Fusion looks interesting, especially with kitting services, but it looks aimed at hobbyists that do maybe 10 units. I use Tindie and have done >200 units in the last 7 months. Will probably move to selling off my web site if the volume goes up much as Tindie doesn't really add that much value. I would probably keep tindie as a channel, though.

author: Kasper
author_rank: Frequent Contributor
timestamp: January 31, 2021, 06:25:12 pm
content: I think Seeed has been offering PCBA for at least a couple years, probably longer. I actually went the other direction when trying low cost fabs, I started with Seeed then tried JLC. Been happy with both of them.Haven't checked recently but a while ago Seeed would make some components free if you use PCBA.Congrats on the >200 units. I'm at 0 myself, but hopefully some day that will change.

author: tszaboo
author_rank: Super Contributor
timestamp: January 31, 2021, 10:13:18 pm
content: I've asked them for a qoute, but their pricing wasnt really interesting compared to other chinese fabs, as I recall.
Ag vs Ni/Au finish - Page 1
Forum section: electronics / general

author: olkipukki
author_rank: Frequent Contributor
timestamp: January 15, 2021, 11:32:52 am
content: What type of applications you would consider a silver surface finish instead of gold?

author: asmi
author_rank: Super Contributor
timestamp: January 15, 2021, 01:35:24 pm
content: High currents? Specific resistance of gold is about 40% higher than that of a silver, for nickel it's much worse - over 4 times higher than silver.

author: jpanhalt
author_rank: Super Contributor
timestamp: January 15, 2021, 02:14:01 pm
content: Immersion silver can be a problem in certain environments ("creep corrosion"):https://www.dfrsolutions.com/hubfs/DfR_Solutions_Website/Resources-Archived/Publications/2005-2007/2007_08_creep_corrosion_on_lead-free_pcb_in_high_sulfur_environments.pdf

author: olkipukki
author_rank: Frequent Contributor
timestamp: January 15, 2021, 07:59:10 pm
content: Quote from: asmi on January 15, 2021, 01:35:24 pmHow 'high' is that?

author: asmi
author_rank: Super Contributor
timestamp: January 15, 2021, 09:10:18 pm
content: Quote from: olkipukki on January 15, 2021, 07:59:10 pm"High" current relatively to what's possible with other terminations.See examples for PJ-102A (tin termination) vs PJ-102AH (silver). Latter has current rating of 5 Amps vs 2.5 Amps for the tin-terminated version. Otherwise those two parts are identical.

author: arlo_g
author_rank: Contributor
timestamp: January 17, 2021, 08:15:34 pm
content: A silver surface finish might be called for in RF/microwave applications.The usual "Gold" surface finish is ENIG, which consists of vanishingly thin "immersion" plated gold on top of an electrically significant thickness of electroless plated nickel. Nickel is needed as a diffusion barrier between gold and copper, but Ni is a mediocre electrical conductor with terrible RF conductivity because of its high relative permeability which reduces the skin depth that carries high frequency current. Making the Au layer thick enough that it dominates the RF conductivity is not usually an option because it is 1) expensive and 2) not consistent with reliable solder joints. Reliable soldering to thick Au requires esoteric tin-free solder.Silver is a good conductor, and has less severe diffusion problems than Au when plated on copper. It also can remain solderable for longer than bare copper.

author: David Hess
author_rank: Super Contributor
timestamp: January 18, 2021, 08:55:49 pm
content: In an RF application like a cavity, silver plating yields about a 10% improvement over bare copper.

author: ANTALIFE
author_rank: Frequent Contributor
timestamp: January 18, 2021, 11:47:00 pm
content: As always depends what you are doing, but attached is a good summaryA surprising fact I found out about ENIG is that the Nickel/Phosphorus part makes surface magnetic, so if you are designing something that is meant to say measure tiny variations in magnetic fields then you should not use ENIG
Order boards now and ship before Chinese New Year?  Where? - Page 1
Forum section: electronics / general

author: Civilenjuneer
author_rank: Newbie
timestamp: February 01, 2021, 01:48:54 am
content: My regular supplier just told me they can't ship any boards until after Chinese New Year (Feb 19th), but I am in a bind and need some sooner. Does anyone know if any of the regular places can ship before? I have 2 boards I need, one is 2 layer, white soldermask, ENIG and I generally get them panelized but I can do without for a quick short batch. Other one is 4 layer, white solder mask and ENIG also... again usually get them panelized but individual would be OK. I usually order both boards in batches of 1,000 (1000 boards, not 1000 panels) but a couple hundred of each would tide me over until my usual supplier can ship.

author: 48X24X48X
author_rank: Frequent Contributor
timestamp: February 01, 2021, 03:02:36 am
content: Unless you are looking elsewhere out of China, I wouldn't want to risk it for board quality. Based on many years experience ordering from China, boards made during this time of the year is a hit or miss. Everyone wants to quickly finish their work and go home (at least less this year). I think JLCPCB continues to run this CNY, probably on a smaller scale production and limited layer count.

author: NorthGuy
author_rank: Super Contributor
timestamp: February 01, 2021, 05:00:26 pm
content: PCBWay can still do it:https://www.pcbway.com/blog/Activities/Holiday_notice_____2021_Chinese_New_Year.html

author: mon2
author_rank: Frequent Contributor
timestamp: February 03, 2021, 09:12:00 pm
content: Due to the CNY holidays, you can try JETPCB. Met them in Taipei and they have had a US office for a while now. Excellent quality PCBs. Have used them many times for upto 6L. Cost wise they are not JLCPCB but they can support requirements that JLCPCB cannot touch.They usually do not close for the CNY holidays but you can confirm.Recommend them highly.http://us.jetpcb.com/PS: They build in Taipei.

author: MadScientist
author_rank: Frequent Contributor
timestamp: February 03, 2021, 09:13:07 pm
content: JCL are continuing to make 2 layer pcbs during the new year holidays

author: S. Petrukhin
author_rank: Super Contributor
timestamp: February 08, 2021, 01:05:55 pm
content: It's fun to work in the international market and have a long vacation.
Elecrow assembly mainstream components overpriced? - Page 1
Forum section: electronics / general

author: Tif
author_rank: Contributor
timestamp: January 18, 2021, 06:49:46 pm
content: Hi,I have been using elecrow assembly services a few times and I am very satisfied with the quality of their service.Recently, I have started to look at the prices they charge you for components since I need to order medium batch of about 500 boards (20 unique parts, about 40 components).In their quote, they want to charge me 3 cents a 100 nF cap used twice in the board (CC0603KRX7R9BB104, US$ 0.0031 par unit for qty 1000 @ LCSC) => almost10 timesthe price!I can understand that they charge for component preparation, overage, etc, but here we are talking about a 100 nF cap in 1000 pcs qty! If they charge me $0.03, that's $30 for the 1000 pcs. Even if they buy a complete reel, it's only $11.6 (and you get 4000 pcs!).So I asked their service to tell me more about their pricing and they respondedQuoteAll right, these fees seems fair to me, but still, a 30% fee is very far away from the actual 968%...Has anyone experienced similar prices and fees?
Who is familiar with Yucheng Technology machines - Page 1
Forum section: electronics / general

author: Sivers
author_rank: Newbie
timestamp: January 17, 2021, 06:24:23 pm
content: Hello.Anyone who has experience using the installation machines of Yucheng Technology. http: // w w w .yuchengtech.nethttps://v.youku.com/v_show/id_XNDExNDg5NTIwMA==.html?spm=a2hbt.13141534.1_2.d_1_55&f=22282265

author: 48X24X48X
author_rank: Frequent Contributor
timestamp: January 18, 2021, 12:41:03 am
content: Long long time ago, there was a company named Yushengtech run by 2 guys names Li Sheng and Cheng (I can't remember his surname). After a short while, they have disagreement and went on separate ways. Li went on with his company called Eleesen and Cheng with Yuchengtech (they are obsessed with company naming after themselves). Both company machines are still similar having that push feeder mechanism and probably running similar software and firmware (probably updated on different path after they split). Eleesen has since have SmallSMT as their distributor outside of China while Yuchengtech allows you to buy from them directly without much English support. I owned one of Eleesen's machine sold by SmallSMT that I eventually sold off after having issues getting it to work reliably. Yuchengtech's machine has since made some changes and added a built-in PC into their machines but concentrate mainly on 2-3 models only. While, Eleesen have numerous machine variations with some having 4-head and CL feeder supports. I did have some chats with Cheng before decided to buy something better in the market but I can see he seems knowledgeable on his machines. I do like the tiny details he has upgraded his machine which reflects how much he notice the drawbacks/issues with the earlier versions of the machines. At RMB27K (~USD4.2K) for his top specifications machine (which is better than most drag feeders machine out there that copied earlier versions of TM220A & TM240A but definitely below par when compared to bigger machines from HWGC/Kayo/Boreytech/Bovi/etc), it fits into small batch assembly well as long you are willing to work with the quirks of the push feeder (and changing reels on them). Cheng has since refreshed and did a lot of work on the software and it looks and feels a lot better than the older ones now.This is just my humble opinion after having combed through most manufacturers in China before buying my current machine.

author: Sivers
author_rank: Newbie
timestamp: January 18, 2021, 07:37:32 pm
content: 48X24X48X thank you for your reply.Please share your experience with Pick & Place machines when nothing else was involved.
Buying reels from places other than DigiKey etc - Page 1
Forum section: electronics / general

author: Northy
author_rank: Regular Contributor
timestamp: January 13, 2021, 11:01:44 am
content: Hi,I've seen a few mentions that DigiKey etc isn't really the place to buy reels of components for manufacturing.If you only buy a reel of components every few months for example are there any better options?Do many people buy parts in from the Far East? Who are the trusted sources?Thanks,G

author: Mangozac
author_rank: Frequent Contributor
timestamp: January 13, 2021, 11:56:32 am
content: Arrow.com is very competitive once you place a few orders and get gold member status (also gets you free rerealing and free shipping). I get a lot from them these days. Mouser I generally find cheaper than Digi-Key for reels.I occasionally order from LCSC but will usually only go for Asian brands for resistors.Edit: also, the TI and Microchip online stores are proving to be quite competitive (the former in particular).

author: mikeselectricstuff
author_rank: Super Contributor
timestamp: January 13, 2021, 11:58:55 am
content: Look up the list of franchised distributors on the manufcturer's website

author: SMTech
author_rank: Frequent Contributor
timestamp: January 13, 2021, 12:09:57 pm
content: Quote from: mikeselectricstuff on January 13, 2021, 11:58:55 amIndeed, we buy a very large mix of both reels and cut tape, the total volumes add up to fairly significant sums over a year so we get discount structures (% on some line types, last break price regardless of qty on others etc) on RS and Farnell, this leaves Mouser and Digikey for stuff UK suppliers don't stock. However as a general rule for the more boring stuff, if Anglia stock it, they are still the cheapest place. Of course in the UK Brexit is affecting all these choices because free frictionless trade is a total myth spoken and believed only by fools. This probably plays into the hands of RS and Farnell as it also affects purchasing from Mouser/Digikey as we don't have a US deal yet but the EU had something.
Cost of making one shot, large PCBs (for antennas) - Page 1
Forum section: electronics / general

author: cdev
author_rank: Super Contributor
timestamp: January 06, 2021, 03:16:56 pm
content: If its affordable, I'd like to make some largish antennas out of double or single sided PCB material.What kinds of costs would I be looking at to make something say 1 meter by 750 mm in size?Probably a lot, right?

author: wraper
author_rank: Unknown
timestamp: January 06, 2021, 03:19:13 pm
content: Over $1k for 5 pcs and most likely not less at places which will make a single PCB.

author: NorthGuy
author_rank: Super Contributor
timestamp: January 06, 2021, 03:35:26 pm
content: The longest I made was 500 mm. It was about $40 for 10 pieces at PCBWay.You can build a longer piece by connecting shorter pieces together. Then there's no limit how long you can go.

author: cdev
author_rank: Super Contributor
timestamp: January 06, 2021, 03:37:21 pm
content: Ouch!This is a good argument for other means of making them.

author: GerardG
author_rank: Regular Contributor
timestamp: January 06, 2021, 03:40:03 pm
content: Hello,Keep in mind that a production sheet for the most machines are about 610x510mm.Then you need tooling holes for the process. So the net size is smaller.The manufacturer buys sheets of 1220 x 1020 (or 1080)

author: cdev
author_rank: Super Contributor
timestamp: January 06, 2021, 07:18:17 pm
content: Thank you!Quote from: GerardG on January 06, 2021, 03:40:03 pm

author: mikeselectricstuff
author_rank: Super Contributor
timestamp: January 06, 2021, 07:34:48 pm
content: PCBWay go up to 1200mmm - you could try their online quote siteOversize shipping fees can add a lot, both for the size and the weight of packing needed to keep it flat
SMT Washers for Board Spacing and Custom Part to Reel Service - Page 1
Forum section: electronics / general

author: bugrobotics
author_rank: Regular Contributor
timestamp: January 05, 2021, 01:35:00 am
content: Hi all,Looking for a reel mounted SMT standoff in washer form (as in no through hole required like the standard spacers from Wurth/Keystone/Mac8). The PCB I'm mounting currently needs to be spaced off their mounting standoffs anywhere between 0.3-0.75mm. M2 screw is used to mount the PCB to the case. I am currently implementing M2 brass washers as spacers that get soldered to a pad on the bottom of the board. Would be cool if anyone knows of any off the shelf spacers available in this form. I could use the THC-1.6 spacers from Mac8 but the screw head would not be able to squeeze the PCB as the required through hole size is larger than the screw head diameter. Could then implement a washer but then it's another part and I'd like to keep it clean as possible.This brings me to my next question...Does anyone know of a service where you can send a custom part (in this case a small brass washer) to be added to a reel? I'm in Denver, CO.Any and all suggestions welcomed. Thanks.EDIT:Thinking about this a bit more and trying a few things I may need to dial back the OCD. Looks like it will fit OK without the spacer.I'd still like to know if a washer is available as a reel part and if there are any services that custom package parts.

author: SMTech
author_rank: Frequent Contributor
timestamp: January 05, 2021, 10:14:30 am
content: I don't think I've seen one, as you may have noticed the most obvious sources have limited selections of types and sizes - this is a low profile threaded insert for instancehttps://www.keyelco.com/category.cfm/Spacers-Standoffs/Standoffs-Spacers-Inserts-Surface-Mount/id/1335.There are re-reeling services out there but I don't know if they can package something that doesn't have an existing generic tape, for some small levels of extra height just opening apertures in your stencil around a mounting hole annulus might work, you see that on PC motherboards for instance.
LTCC Manufacturers in the US - Page 1
Forum section: electronics / general

author: ezalys
author_rank: Frequent Contributor
timestamp: December 31, 2020, 04:27:05 am
content: Hey all,I'm trying to have a small LTCC board made. Maybe one or two layers, quantity anywhere between 50 and 100. Lead time is really the key thing. Ideally in the northeast of the US but anywhere in the US is also fine. If neither of those, anywhere that has a good reputation and is fast will do.Thanks!

author: bob91343
author_rank: Super Contributor
timestamp: December 31, 2020, 05:36:15 am
content: https://en.wikipedia.org/wiki/LTCC

author: jduncan
author_rank: Regular Contributor
timestamp: December 31, 2020, 07:04:44 pm
content: https://en.wikipedia.org/wiki/Co-fired_ceramic
JLCPCB - confused about Gerber analysis - Page 1
Forum section: electronics / general

author: JohnnyMalaria
author_rank: Super Contributor
timestamp: December 27, 2020, 11:28:28 pm
content: Hi,I created a 2-layer PCB in Eagle with 6 and 20 mil wide traces and minimum 6 mil spacing.When I run the JLCPCB Gerber analysis, it reports:Analysis Resultslayers : 2minimum trace width : >=10 milminimum trace spacing : >=10 milminimum drill size : 0.61 mmwidth : 142.24 mmheight : 93.98 mmAnd their capabilities state that the minimum trace width/spacing on outer layers is 5 mil.So, I don't know what to make of the analysis report. Is it saying that my traces have to be >10 mil? Or does it think none of my traces are less than 10 mil?Thanks.

author: ebastler
author_rank: Super Contributor
timestamp: December 27, 2020, 11:44:22 pm
content: I think it's the latter. The report is meant to be a summary of the design parameters they found; I don't think it directly ties these back to any JLPCB design rules.So they incorrectly state ">= 10 mil" if your design actually includes smaller structures. Doesn't seem to matter though: I just checked a design I had them produce recently -- their anaysis also claims ">= 10 mil", but they manufactured the 5 mil traces and spacing nicely.

author: phil from seattle
author_rank: Super Contributor
timestamp: December 28, 2020, 01:19:35 am
content: I wouldn't worry, their gerber stuff has a number of bugs. Fortunately, they don't actually use it for manufacturing.
Eagle/PCBLayout.com vs. JLCPCB price - Page 1
Forum section: electronics / general

author: JohnnyMalaria
author_rank: Super Contributor
timestamp: December 27, 2020, 11:45:54 pm
content: Just curious...Eagle has a built-in PCB quote feature that uses PCBLayout.com. It seems it has a blanket price of $1 per pad/pin. I have a 2-layer design with 323 "pins" and the quote is $328 with a 10-day turnaround. JLCPCB is about $17.50 for 5 boards with a 8-16 business day delivery.Why would I choose the PCBLayout.com option?

author: rea5245
author_rank: Frequent Contributor
timestamp: December 27, 2020, 11:51:51 pm
content: There is an Eagle plugin that that pops up PCBShopper.com in a browser window and shows prices for manufacturing your board from over 20 different companies. Get the plugin athttps://github.com/JeremyRuhland/pcbshopperDisclosure: I run PCBShopper (but I did not write the plugin).- Bob Alexander

author: JohnnyMalaria
author_rank: Super Contributor
timestamp: December 28, 2020, 12:04:33 am
content: Quote from: rea5245 on December 27, 2020, 11:51:51 pmThanksI just tried it - very easy and quick. JLCPCB came out cheapest...

author: phil from seattle
author_rank: Super Contributor
timestamp: December 28, 2020, 01:17:19 am
content: In general, a PCB quote from inside an EDA package is not likely to pass the "economic sniff test". There are some exceptions though - basically captive EDAs from board houses. Earlier versions of Eagle had quote plugins from different boar houses and they they were all similarly overpriced.
Anyone have experience w/ brokers Abacus, Classic, Rotakorn, One Stop, iodParts? - Page 1
Forum section: electronics / general

author: IDEngineer
author_rank: Super Contributor
timestamp: December 22, 2020, 10:46:24 pm
content: Somehow a Bosch part that we use is suddenly out of stock at all authorized distributors and the factory is backordered until March/May/August (depending upon whom you ask). We need several hundred parts to get us to the point where the factory and/or its authorized distributors say they'll have stock again.We and our contract manufacturing house have zero experience dealing with brokers, but I can imagine it's a shady business. In fact our CM house has a policy against buying from brokers at all... we'll have to buy them ourselves and provide them.Does anyone have any experience, good or bad, with the following brokers who claim to have stock?Abacus TechnologiesClassic ComponentsRotakornOne Stop ElectroiodPartsAny guidance will be greatly appreciated. Thanks!EDIT: Yes, we've already considered pin compatible substitutes. We evaluated them when we chose this part, and Bosch's own recommended substitute is anightmareof hideously bad design choices. Plus we really don't have time to redesign the PCB and firmware (plus qualification) before we'll run out of parts. This part is current production so it's just a short term problem.

author: IDEngineer
author_rank: Super Contributor
timestamp: December 23, 2020, 01:21:51 am
content: Hmm... tried moving this question to a different subforum but now I find I cannot delete my own, unanswered message.Please delete this thread and leave the one in the "Projects" subforum where I'm hoping it will get some responses.

author: cdev
author_rank: Super Contributor
timestamp: December 23, 2020, 03:36:15 am
content: Abacus the sex cult owned store?
off the shelf component picker head - Page 1
Forum section: electronics / general

author: Simon
author_rank: Unknown
timestamp: December 21, 2020, 09:33:33 pm
content: Are there any off the shelf component pick up heads that can be bought? ideally something that can be rotated by a motor.

author: Mangozac
author_rank: Frequent Contributor
timestamp: December 21, 2020, 09:50:11 pm
content: As in a pick and place head?https://www.robotdigg.com/product/559/Surface-Mounting-PnP-Head-for-OpenPnP

author: Simon
author_rank: Unknown
timestamp: December 22, 2020, 07:59:21 am
content: Yep that's the kiddy, you'd be amazed how good your googlefoo needs to be to find these

author: Simon
author_rank: Unknown
timestamp: December 22, 2020, 08:39:33 am
content: I'm confused does this:https://www.robotdigg.com/product/800/OpenPnP-nozzle-CP40LVmount straight to this:https://www.robotdigg.com/product/559/Surface-Mounting-PnP-Head-for-OpenPnP?

author: SMTech
author_rank: Frequent Contributor
timestamp: December 22, 2020, 09:34:57 am
content: Good question, from the pictures the head is designed to take Juki nozzles, (green spring loaded) whereas the nozzle in the picture looks simpler. You can also find pick heads that take Juki Nozzles on Ali in various counts form 1-4 at least with and without Z rail.

author: Mangozac
author_rank: Frequent Contributor
timestamp: December 22, 2020, 12:17:33 pm
content: Yeah, it says JK nozzle adaptors. It's an OpenPNP head system and from what I've seen most of those guys are using Juki nozzles. These have become the defacto standard in the same way that Yamaha CL feeders have.

author: Simon
author_rank: Unknown
timestamp: December 22, 2020, 05:02:07 pm
content: So Juki nozzles are a standard? I don't need the Z travel just the rotation motor and then the stepper motor driver for it.

author: langwadt
author_rank: Super Contributor
timestamp: December 22, 2020, 05:37:59 pm
content: Quote from: Simon on December 22, 2020, 08:39:33 amshouldn't it be these ones?https://www.robotdigg.com/product/1638/7500-to-7508-nozzles-compatible-for-RS-1-PnP-Machine

author: Simon
author_rank: Unknown
timestamp: December 22, 2020, 05:48:13 pm
content: So do those just fit into the PnP head as supplied?

author: langwadt
author_rank: Super Contributor
timestamp: December 22, 2020, 06:12:54 pm
content: https://youtu.be/HqL2Nd4ixHI

author: Simon
author_rank: Unknown
timestamp: December 22, 2020, 06:36:34 pm
content: Right so I can buy that picker and Juki nozzle and that's the unit complete.

author: Mangozac
author_rank: Frequent Contributor
timestamp: December 22, 2020, 10:23:08 pm
content: Looks like that's the case...
JLCPCB Wifi modules - Page 1
Forum section: electronics / general

author: phil from seattle
author_rank: Super Contributor
timestamp: December 19, 2020, 06:14:27 pm
content: I don't know if this is a recent addition but they have several Wifi Modules in their parts library. Ai-Thinkers and Espressif designs. Anyone used these on a JLCPCB board? Anything to watch out for?

author: Mangozac
author_rank: Frequent Contributor
timestamp: December 19, 2020, 08:29:07 pm
content: Note that they're not an authorised distributor for Espressif. It may or may not matter to you but we have a rule of only using integrated circuits from authorised distributors.

author: phil from seattle
author_rank: Super Contributor
timestamp: December 19, 2020, 09:39:33 pm
content: Is LCSC? That's where they are getting them.

author: Mangozac
author_rank: Frequent Contributor
timestamp: December 19, 2020, 09:53:58 pm
content: No, LCSC isn't. I specifically asked Espressif.
Transparent ESD safe material - Page 1
Forum section: electronics / general

author: olkipukki
author_rank: Frequent Contributor
timestamp: December 05, 2020, 08:34:41 pm
content: Does <subj> exist or someway DIY with a 'generic' material and a special treatment?Added: Need to be able to machine a custom shapes and drill holes

author: Kean
author_rank: Unknown
timestamp: December 06, 2020, 04:23:26 pm
content: I have recently been looking around for something like this myself again. I know I've looked several times before.I've used on Acrylic (Perspex/PMMA) in some test jigs and such that I have then treated with Desco Reztore Topical Antistatic - but I have no data on how well that works or lasts.I also bought a spray can of Techspray Licron Crystal ESD but I'm not sure if I have actually tried it yet. It is a lot more expensive but seems like it would be a somewhat more permanent treatment.https://desco.descoindustries.com/DescoCatalog/Education-Awareness-Accessories/Reztore-Antistatic-Coating/10415/https://www.techspray.com/licron-crystal-esd-safe-coating-3

author: mxhll
author_rank: Contributor
timestamp: December 11, 2020, 11:35:16 am
content: There are some metallised film materials that you could apply to a clear acrylic backing.(Basically thin antistatic bags, so only mediocre optical clarity).If it is a 2D shape, you could look at ITO coated glass.I have no experience in machining, but i can imagine it can be waterjet-cut or machined with abrasive/diamond tooling.

author: tszaboo
author_rank: Super Contributor
timestamp: December 11, 2020, 01:21:09 pm
content: Quote from: olkipukki on December 05, 2020, 08:34:41 pmThey usually add carbon into the material to make it conductive.Carbon is black.So I would look for dissipative materials. Or review the requirements.

author: GerardG
author_rank: Regular Contributor
timestamp: December 11, 2020, 01:31:01 pm
content: Take a look at this one.Acrylic antistatic material.https://wkhgroup.co.uk/materials/antistatic-acrylic-and-polycarbonate

author: olkipukki
author_rank: Frequent Contributor
timestamp: December 14, 2020, 11:47:48 am
content: Quote from: mxhll on December 11, 2020, 11:35:16 amInteresting, but the most available is very thin (around 1mm) for me, above that - custom and min order $$$

author: Whales
author_rank: Super Contributor
timestamp: December 14, 2020, 11:58:17 am
content: I wonder if 'smoked' perspex uses carbon as the tinting agent?

author: olkipukki
author_rank: Frequent Contributor
timestamp: December 15, 2020, 09:52:19 am
content: Quote from: NANDBlog on December 11, 2020, 01:21:09 pmThe requirements are quite simple - towards 100% transparent machinable and cost-effective material that easy to source from more than one supplier
Test points/designs for measuring PCB flux residue leakage currents? - Page 1
Forum section: electronics / general

author: rt
author_rank: Regular Contributor
timestamp: December 12, 2020, 04:52:34 pm
content: Any recommendation techniques for placing additional pads/traces/components to allow post-assembly measurement of leakage currents?Just trying to quantify the effectiveness of our cleaning procedures before the next version of our ADC board.rt

author: kylehunter
author_rank: Regular Contributor
timestamp: December 13, 2020, 01:52:22 pm
content: Quote from: rt on December 12, 2020, 04:52:34 pmI doubt you'll have success doing that. The leakage through an NC/RMA will likely not be measurable with an ADC unless you're using a very accurate, high resolution ADC. Especially after you washed it. Typically flux residues will only be an issue on high-speed/RF boards. A better method is to use the IPC R.O.S.E. Method 2.3.25. That tests the conductivity of the residue dissolved from the entire board after washing. Do note: depending on the flux chemistry used, this test may or may not be effective.To be fair, the industry is lacking a good cleanliness standard right now. The ROSE method is great for truly conductive flux's, like OA water soluble's. For RMA/NC, we've had very mixed results with it.

author: IconicPCB
author_rank: Super Contributor
timestamp: December 14, 2020, 01:29:17 am
content: May be searching for SIR ( surface insulation resistance) may give You a clue.
Tool for opening & closing ZIF / FPC connectors? - Page 1
Forum section: electronics / general

author: nctnico
author_rank: Super Contributor
timestamp: December 05, 2020, 09:59:32 pm
content: Is anyone aware of tools to make it easier to work with ZIF connectors for FPC cables even for ham fisted blokes? I'm not a fan of using these because they are so fiddly to work with but sometimes it is unavoidable.

author: S. Petrukhin
author_rank: Super Contributor
timestamp: December 06, 2020, 08:39:28 pm
content: https://aliexpress.ru/item/32763766213.html

author: exmadscientist
author_rank: Frequent Contributor
timestamp: December 11, 2020, 06:17:53 am
content: I have found the Wiha Chip Lifter (27920 is one version; they're all the same except for the handle) to be surprisingly useful for opening vertical slide lock FFC connectors. It's good for a lot of other things too, including prying off stuck faston terminals and threatening people who think FFCs are a good idea....

author: radar_macgyver
author_rank: Frequent Contributor
timestamp: December 11, 2020, 06:21:52 am
content: Plastic "spudger", like the ones iFixit popularized. I used to use small flat-blade screwdrivers (~2mm) but these can break the tabs off.
Cable supplier recommendation - Page 1
Forum section: electronics / general

author: pisoiu
author_rank: Regular Contributor
timestamp: December 09, 2020, 01:43:50 pm
content: Hi all,Until now I worked with some european supplier of cables for my products but I need to step up the quantities and I would like to look for a supplier in China for raw wires.I mostly use single copper wire, stranded, pvc insulation, type LGY, purchased from TME/BQ cable, various colors, 0.5 and 0.75mm2.Can anyone make me a recommendation for a supplier from alibaba or elsewhere? I would like to avoid situations where I purchase samples and they're ok, then when I make the final order I get something else.Thanks.

author: Nauris
author_rank: Regular Contributor
timestamp: December 09, 2020, 07:24:25 pm
content: Huh?For that simple of a product I don't think chinese have any real cost advantage over italian/eastern european suppliers. Gamakabel comes to mind first but there are many others.

author: Mangozac
author_rank: Frequent Contributor
timestamp: December 09, 2020, 08:38:58 pm
content: ^ this. Plus, cable is heavy, so unless you're bringing in containers of it it's very difficult to compete with the cost of local suppliers. Don't forget you may need specific certifications for any appliance wire being used for mains voltage (although I'm guessing not relevant to you at 0.5 and 0.75mm).

author: wraper
author_rank: Unknown
timestamp: December 09, 2020, 09:01:56 pm
content: Quote from: Mangozac on December 09, 2020, 08:38:58 pmYeah, I buy cheap connectors from China and for the vast majority of them shipping costs more than 50% of the part itself (I buy thousands at a time). For cables it will be even worse. Even for connectors this makes price advantage quite small, and for cables shipping can easily make it even more expensive than locally sourced stuff.

author: pisoiu
author_rank: Regular Contributor
timestamp: December 09, 2020, 09:50:45 pm
content: Well, I didn't thought that the price difference is so small and the shipping fee will erase it....Thanks for the tips.
TH wave soldering - slots in PCB a problem? - Page 1
Forum section: electronics / general

author: mikeselectricstuff
author_rank: Super Contributor
timestamp: December 13, 2020, 12:28:30 pm
content: Does anyone have experience of wave soldering a PCB that has (2mm) isolation slots ?Does the solder squirt through the slots to the top of the PCB, or does surface tension keep it out?

author: fcb
author_rank: Super Contributor
timestamp: December 13, 2020, 01:34:36 pm
content: 2mm is pushing it. It will depend somewhat on length of slot and angle w.r.t the wave.Tekspray WonderMask is commonly used by CEM's to sort problems like yours out.

author: jmelson
author_rank: Super Contributor
timestamp: December 13, 2020, 09:36:59 pm
content: Quote from: fcb on December 13, 2020, 01:34:36 pmOr, you can tape the bottom of the board with Kapton tape. It resists soldering temperatures well, and peels off later with no residue. This should work fine to keep solder out of the slot. I use it to prevent a dip-soldered board from getting solder into some dual-row header holes when soldering the board.Jon

author: tszaboo
author_rank: Super Contributor
timestamp: December 13, 2020, 11:10:23 pm
content: They set up the waves, so they are barely above where the PCB is. Wave soldering is often times used for power supplies, that have these isolation slots.The slot is not really different than the edge of the PCB. If you dont feel comfortable, ask for selective wave soldering. Or accept that they might ruin a board or two at the beginning of you batch. But I think it will be fine.

author: IconicPCB
author_rank: Super Contributor
timestamp: December 14, 2020, 01:26:41 am
content: You can always ask the PCB shop to apply peelable soldermask.

author: Niklas
author_rank: Frequent Contributor
timestamp: December 14, 2020, 08:09:05 pm
content: It could depend on the board dimensions and weight of the components. We had a 2 layer FR4 board with a Hahn 30VA transformer in one corner and 2.4 mm routing under relays and around the edge. No problems with lead free wave soldering.Another board, approx A4 sized, and 4 layers FR4, with the same transformer and also a heat sink with some semiconductors caused issues with the same slots in the center of the board. Had to change from 2.4 mm routing for 4 holes for support points to the heat sink as the board dipped into the wave due to the weight. We already had 1 mm routing between pins on the power semiconductors so that was used instead for the holes. 2.4 mm routing was still possible around the edge without any problems.
Neural Network powered Assembled PCB inspection tool  - Page 1
Forum section: electronics / general

author: jpedroc
author_rank: Contributor
timestamp: November 19, 2020, 03:31:07 pm
content: Hi all,We have developed a neural network capable of detecting faults on the electronics components placed on a PCB just from a photo.The service has been released a month ago:www.AgnosPCB.comPlease feel free to take a look at our site and the current visual inspection tool: the web Apphttps://app.agnospcb.com/(You just need to drag and drop the photos you have taken to your PCBa)This neural network powered inspection tool can detect missing/misplaced or rotated elements on any PCBA. It does not matter the type of elements placed/ PCB architecture/ color or size of the components."official" Agnospcb.com Forum thread:https://www.eevblog.com/forum/eda/neural-network-powered-assembled-pcb-inspection-tool-(aoi)/msg3331110/#msg3331110
GF-12HC/HT  Reflow Oven - Page 1
Forum section: electronics / general

author: KG7AMV
author_rank: Frequent Contributor
timestamp: November 13, 2020, 06:37:18 am
content: The Price Was Right.. I could Not Pass it Up!! GF-12HC/HT PCB Reflow Oven! Anyone have experience with this model?Now have to think about what I want to build or do with it.. May have to order some open source PCB's and Stencils and give it a go after the holidays.Video.https://youtu.be/lT2MkcTNlqQSpecs..https://www.ddmnovastar.com/userfiles/file/pdf/GF-conveyer-&-batch-reflow-oven-Lit-R0.pdfI may have a line on a bench top pick n place machine also.

author: IconicPCB
author_rank: Super Contributor
timestamp: November 13, 2020, 07:28:55 pm
content: I have one of those.You will need the security codes to be able to set it up, auto tune the the oven, and set the profiles.A fine small oven, awkward manufacturer to deal with.They may ask for a thousand dollars to support it should you need the information about the machine.Did you score the user manual with the machine?

author: KG7AMV
author_rank: Frequent Contributor
timestamp: November 13, 2020, 08:54:35 pm
content: I Printed the user manual rather poor and lacking detailshttps://www.pcbunlimited.com/pdf/Reflow_Solder_Oven_GF_12HC.pdfI can set the profiles seems to not require a code.I have the 2 codes Got them from a post on smtnet. Tested them and they work on my appliance.Tune: F1 - Left - Down - RightSetup: F2 - Left - Up - DownI seen they wanted seven and a half bills for their software umm nope! Not for Personal Lab Use!Not sure it will get much usage.

author: IconicPCB
author_rank: Super Contributor
timestamp: November 14, 2020, 04:55:05 am
content: The manual seems to be a third party effort.It is somewhat different to the one I have.What was the right price?

author: KG7AMV
author_rank: Frequent Contributor
timestamp: November 14, 2020, 10:05:46 am
content: I sent you a PM.Yea, I found another version that was similar but the one I posted earlier printed better. Wish there was a more detailed manual by seeing what they charge retail for these there should be a manual 2" thick lol.The other manual about the same as the other.https://www.stencilsunlimited.com/pdf/gf_12hc.pdf

author: IconicPCB
author_rank: Super Contributor
timestamp: November 14, 2020, 11:01:05 am
content: I had to change wiring to Australian 3 phase power.Had to trace it out and modify it.A bit of a gamble fortunately the instalation solid state relays and heaters are good for three phase power'
need schematic for Quad IQ feeder - Page 1
Forum section: electronics / general

author: jmelson
author_rank: Super Contributor
timestamp: November 13, 2020, 11:36:08 pm
content: Does anybody know where to get schematics for a Quad IQ feeder? They have a quite complicated board in them with a micro, sensors and motor drive.I have a feeder that worked for a while, now it just gives a pattern of blinking LEDs when you press any button.Thanks,Jon
Approval and cost for South Africa, Australia and Europe - Page 1
Forum section: electronics / general

author: calvingloster
author_rank: Regular Contributor
timestamp: November 13, 2020, 09:11:24 am
content: Hi AllI have a product i want to sell in South Africa, Australia and Europe. The product will be manufactured in South Africa and sold directly to customers in South Africa, Australia and Europe.The product uses an FCC and CE approved wifi module however this is integrated onto a PCB. As i understand i will still need to do EMC testing and Safety testing.What lab and what tests will i need to do to be able to sell the product in South Africa, Australia and Europe and what cost am i looking at?

author: Mangozac
author_rank: Frequent Contributor
timestamp: November 13, 2020, 11:15:56 am
content: That's not enough information to give a definitive answer but as a guideline for Australia:Safety to AS/NZS/IEC 60335 is around AU$6k-10k (depends on whether there is a "hard" on off switch. EMC to CISPR14 around AU$3k from a formal test lab. If you're using the same type and gain antenna the radio module was verified with there should be no additional testing needed for radiocommunications compliance.
Reflow oven "air knife" - Page 1
Forum section: electronics / general

author: mpbrock
author_rank: Contributor
timestamp: November 12, 2020, 12:42:28 pm
content: Hi guysI can't find much info online on this - one of our reflow ovens (an "old timer") has nitrogen input with a "Air knife" which you can control the speed + gas temperature. The PCB goes through pre-heat zone #1, zone #2 and then gets blasted by the "Air knife" before going in to the reflow zone.All I can find online is air knifes in relation to wave solder machines.Thanks in advance

author: Mangozac
author_rank: Frequent Contributor
timestamp: November 13, 2020, 01:09:49 am
content: I'd suggest air knife is probably the wrong search term - it's generally intended for a violent air blast for removing excess coatings/compounds/etc. But that said, "Air Knife" brings up plenty of matches for similar items on Alibaba...
Is there a market for a 140v brushless motor driver board? - Page 1
Forum section: electronics / general

author: FaustElectronics
author_rank: Newbie
timestamp: November 06, 2020, 09:52:17 pm
content: I'm in the process of designing an open source 140v max motor driver board for myself. I'm wondering if maybe there would be some interest in it, and if it's something maybe I should kickstarter.

author: james_s
author_rank: Super Contributor
timestamp: November 06, 2020, 10:21:08 pm
content: I'd need more details to know whether it's something I could use. What is the use case you have in mind? Is this for small equipment like kitchen appliances, medium stuff like brushless electric lawnmowers, or large stuff like vehicles?

author: FaustElectronics
author_rank: Newbie
timestamp: November 06, 2020, 11:22:33 pm
content: I'm thinking Ebikes and the like 100 amps plus easy

author: FaustElectronics
author_rank: Newbie
timestamp: November 06, 2020, 11:24:29 pm
content: just to add some clarity I'm making an electric skateboard and my 56V odrive seems right at the edge of usability. I'd like to use higher voltage and have comfortable room to spare. I like using higher voltage motors because of the smaller wires.

author: james_s
author_rank: Super Contributor
timestamp: November 07, 2020, 02:35:40 am
content: I'm sure a market exists, there are certainly plenty of e-bikes out there and it is growing. Is there not something commercially available that fills this niche? It's pretty hard to compete with China on this sort of thing.

author: FaustElectronics
author_rank: Newbie
timestamp: November 07, 2020, 08:08:14 am
content: So I'm building off of the odrive. All of the commercial high voltage boards I've seen aren't open source, and I can compete with china because I have pick and place machines

author: NiHaoMike
author_rank: Super Contributor
timestamp: November 12, 2020, 02:28:56 am
content: Extend that to about 170V nominal and you'll also cover 120V mains powered BLDC motors.

author: thm_w
author_rank: Super Contributor
timestamp: November 12, 2020, 08:33:18 pm
content: Quote from: NiHaoMike on November 12, 2020, 02:28:56 am
DIY Preheater options? - Page 1
Forum section: electronics / general

author: cheater
author_rank: Regular Contributor
timestamp: December 24, 2020, 07:25:25 pm
content: Hi all, I was thinking of getting a pre-heater for repairing large PCBs such as motherboards (especially from older computers), but there is nothing out there, really.This threadmentions that using a small pre-heater to locally preheat a pcb will create stress and warping, not sure if I want that. However, one thing that I've been wondering about is, aren't quartz pcb preheaters basically just a mica heating element in a metal box, with a temperature controller? if so, why not just get a large mica space heater that's large enough for my pcb, lay it down (on some sort of frame so it's lifted a few inches off the surface it's on), and control it with a thermal controller? As a bonus you could put your thermocouple down on a large ground plane to find out when that reaches the desired pre-heating temp (say, 150C). Those space heaters are like 2000W and cost absolutely nothing, especially compared to, say, an Aoyue 853A, which can only pre-heat like a small cell phone pcb, and only does 500W. How much heat could I need? If I need more heat output (for faster heating), is it fine to take the heating mats out of multiple space heaters and just stack them on top of each other? Possibly with some thermal interface material inbetween? I understand mica heating elements handle up to 430C, and ceramic ones up to 650C. So if I want a board to heat up fairly quickly, would it be fine to stack three mica heaters and then the board on top of that? My guess is you'd have the multiple layers running for a few minutes at most, and then just the top layer after that to maintain the heat.The nice thing with a space heater like say the one in the attachment is that you not only get the heating elements, but also get a nice grill to put your board on, and it's all really cheap and easily available, which is great for when you want to build a project like this. You'd need some sort of metal tub to put everything in as a housing, and some legs to distance it from the table it's on, but that's not really /that/ expensive.I guess one could adapt one of those open source reflow controllers for this sort of project.
Juki Nozzle Size for Hirose u.Fl Connectors - Page 1
Forum section: electronics / general

author: 48X24X48X
author_rank: Frequent Contributor
timestamp: November 17, 2020, 10:14:11 am
content: Hi guys,Does anyone know what size of Juki nozzle to use for Hirose u.Fl connectors? I believe it doesn't come with a kapton tape for pick and place like other connectors. The middle pin of the connector which is around 0.45mm in diameter is probably the only section a nozzle can pick it up. Around this center pin, there's void area. Would a 502 size nozzle work? Or there's a special nozzle for it?This is how it looks like if you are not familiar with it:

author: Mangozac
author_rank: Frequent Contributor
timestamp: November 17, 2020, 09:49:38 pm
content: No, picking up on the middle pin won't be an option as there will be too much variation in where the part is sitting in the pocket. I haven't placed one of these yet but will be very soon, so I've just compared one with our nozzles. I reckon a 505 nozzle will pick it up. It should seal on the outer coaxial ring.

author: nisma
author_rank: Regular Contributor
timestamp: November 17, 2020, 10:16:34 pm
content: I can confirm 505 works.

author: 48X24X48X
author_rank: Frequent Contributor
timestamp: November 18, 2020, 02:38:06 am
content: Thank you guys. Will try this out. Lucky it is 505 else I would have run out of head to put a different nozzle. Haven't a full reel yet so it's a relief it could work.