hybridfree/eevblog-posts huggingface dataset:
mini FFC connector - Page 1
Forum section: electronics / general

author: adriten
author_rank: Contributor
timestamp: May 24, 2021, 05:55:28 pm
content: I'm looking for a (very) tiny flat cable connector , 4 pin, 0.5 mm pitch, flip type as per the attached picI easily find them but they are too big (6 mm wide) while this one is just 3.5 mmAnyone knows where to find it ?

author: Fraser
author_rank: Super Contributor
timestamp: May 24, 2021, 06:28:07 pm
content: Maybe the JAE FA10 series will suit your needs ?https://www.jae.com/direct/topics/topics_file_download/topics_id=64320&ext_no=08&_lang=en&v=202104081416564023609https://www.jae.com/en/connectors/series/detail/id=64320Fraser

author: adriten
author_rank: Contributor
timestamp: May 24, 2021, 08:47:29 pm
content: @ Fraser: had a look at the specs; yes it seems the dimensions are right Thanks !(now how to tell them I need just one)
REACH compliance - Page 1
Forum section: electronics / general

author: keef46
author_rank: Contributor
timestamp: May 24, 2021, 12:56:36 pm
content: Can anyone explain REACH to me in lay-mans terms....We manufacture devices containing circuit boards, PSU's a display etc..... All of the parts are bought in, the components used to make up the PCB's from standard suppliers. The PCB's are made and assembled by external suppliers. We carry out final assembly and testing. What do we need to do in terms of REACH compliance? What do we need to do to prove compliance?Sorry the vagary - there is lots to be found googling I know - but sometimes its easier just ask someone who might have tackled it before.
Has anyone tried using opaque "paint markers" for labelling cables etc. - Page 1
Forum section: electronics / general

author: e100
author_rank: Frequent Contributor
timestamp: May 23, 2021, 01:03:25 pm
content: These are a relatively recent product that has some kind of acrylic paint dispensed via a conventional looking marker pen. The ink is opaque like regular paint instead of being semi transparent like ink. They seem to be favorite tool of graffiti artists which would suggest that they have a fair degree of weather and sun resistance.

author: jfiresto
author_rank: Frequent Contributor
timestamp: May 23, 2021, 01:15:55 pm
content: I have used paint markers to put stripes on solid-color automotive interior wires. Twenty plus years later, the stripes are still there.

author: oPossum
author_rank: Super Contributor
timestamp: May 23, 2021, 01:19:16 pm
content: Paint markers have been around for a long time. At least 30 years. They are great for marking chips.These work great:http://pilotpen.us/categories/permanent-markers/gold-silver-metallic-marker/

author: jjoonathan
author_rank: Frequent Contributor
timestamp: May 23, 2021, 05:19:24 pm
content: They work great!
Alternative to iTead? - Page 1
Forum section: electronics / general

author: Pack34
author_rank: Frequent Contributor
timestamp: July 07, 2021, 03:06:35 pm
content: When I needed bare PCBs made I used to always use iTead since they were so cheap. It looks like they don't offer that service anymore.I remember there being some website that prices out several Chinese board houses. This is just for personal projects that I don't want to throw a lot of money at and I'm happy to do the small amount of assembly myself.Does anyone have any suggestions?

author: rea5245
author_rank: Frequent Contributor
timestamp: July 07, 2021, 03:09:08 pm
content: Quote from: Pack34 on July 07, 2021, 03:06:35 pmYou're probably thinking ofPCBShopper.com.Disclosure: I run the site.- Bob

author: Pack34
author_rank: Frequent Contributor
timestamp: July 07, 2021, 03:17:23 pm
content: Thanks! Exactly what I was looking for. I think it's been almost four or five years since I've ordered something not assembled.
How assemble flexible PCB - Page 1
Forum section: electronics / general

author: luiHS
author_rank: Frequent Contributor
timestamp: May 17, 2021, 10:32:27 am
content: Hi.Does anyone know how flexible PCB circuits are assembled?I have to make a flexible PCB layout that will mount APA102 2020 or HD107s 2020 digital LEDs.I have a pick and place machine, a Neoden4, but I can't think of how to mount the components on a flexible PCB.Apply the solder paste with stencil, I suppose it will be the same as with a rigid PCB. I guess, but I don't know, that flexible PCBs can also be soldered in an infrared oven.

author: GerardG
author_rank: Regular Contributor
timestamp: May 17, 2021, 12:37:44 pm
content: Hello Lui,Use a carrier plate for assembly and paste printing.You can stick the flex to a 1.6mm PCB and run it through your N4. Placement height needs to be increased a little.When ordering flex boards you can specify that you want a panel of flex PCB glued with the edges to the FR4.Otherwise you need to buy a special carrier for this.I would go for option 1 and use some tape to secure it to an FR4 board for now.
Versatronics RV Not importing rounded edge pads - Page 1
Forum section: electronics / general

author: Jackster
author_rank: Frequent Contributor
timestamp: May 28, 2021, 02:47:57 pm
content: Trying to get a Versatronics RV1 to import our gerbers.Any pads with rounded edges do not show as pads thus we can not place components.Any ideas?

author: TIOUK
author_rank: Contributor
timestamp: May 28, 2021, 09:30:03 pm
content: You can cut out some steps in the import process, checkhttp://electricstuff.co.uk/forum/for info. The op is on here somewhere.

author: Jackster
author_rank: Frequent Contributor
timestamp: May 29, 2021, 01:30:00 am
content: Managed to work out how to use the Modify Layers > Convert Track Group to Pads (paste layer).Was so close this evening but did not realize the whole right-click thing till pretty late.Got it placing pretty late in the evening but looks like we need to calibrate the cameras as they error out saying the component is too small.UI is somewhat dated and is taking a while to work out. Like why are some option menus using checkboxes??!?!Just got to work out how to add custom components now.
DF40 Connector Placement by CM - Page 1
Forum section: electronics / general

author: tacocat
author_rank: Newbie
timestamp: May 17, 2021, 06:36:43 pm
content: Hello,I have some designs that use the Hirose DF40 series of connector (same as the Raspberry PI CM 4). I generally get around 500 of these boards produced every year in batches of 100. I have not yet found a CM that can consistently place these connectors in the center of the pads and I was wondering if anyone has used these connectors in medium volume designs, and if so what CMs do you use for assembly?Thank you,- Curtis

author: DIYGUY Chris
author_rank: Contributor
timestamp: May 19, 2021, 05:01:00 pm
content: Saying DF40 series is not enough to get good guidance, please write the manufacturer part number.if you have any images that explains your request then it will be more helpful.I used those connectors on my board to interface with the Arduino Portenta board which has also high density connectors (see image below).Btw the technical name of these connectors is "Mezzanine connectors" or "board to board connectors" some people call it HRS connectors because of the name of the manufacturer." alt="" class="bbc_img" />
Help for Flex PCB design - Page 1
Forum section: electronics / general

author: CeD
author_rank: Contributor
timestamp: May 06, 2021, 03:22:56 pm
content: Hello everyone,I'm a former electronics engineer but never really worked in my field, which remained a hobby !I'm also a vintage PC repair "specialist".I would like to design a piece of flex cable that would allow repairs on an entire line of vintage laptops (screen hinges), and this cable cannot be found anymore.For that, I would need to "design" a (very simple) flax flex cable, that has both ends re inforced (like these cables often have) to replicate the original part.I haven't designed a pcb since my studies with Eagle many years ago, but I guess I could quickly get back to it.I could also use any software. However a flex cable is a completely different story than a PCB, or so it seemsDoes anyone have like, and example I could start with, a company that you used to create a flat flex (pcbway?) and really any other experience or insight you could share with me ?What would really help me is like- I used that company for the production,- here's a sample pcb layout for software X,then I could start with that and design my own cable...thanks everyone!

author: KL27x
author_rank: Super Contributor
timestamp: May 06, 2021, 07:56:53 pm
content: Designing a 2 layer flex is almost exactly the same as a normal board.Just add a layer to show the shape/placement of the "stiffeners." Name it clearly as the "[top/bottom] stiffener" layer. That's the term they use in the trade. You can also create a third layer for the adhesive area, if you want the stiffener to have a tab that sticks out where you can grab it with tweezers. And make sure your soldermask layer shows a box over the ends of the cable that must be exposed.Just specify the thickness of your polyimide layer for the board, and the thickness of the polyimide stiffener. Fabs that do flex will often give you suggestions based on what material they have, that will be close to what you requested. And then also give you the thickness of the stackup when it's done, including the adhesive that holds it together, soldermask coverlay, and any other jazz. If that looks good, then go with it.The only part that is suck is that you can't get cheap one offs. Most places will charge the same if you want just 1, or a whole sheet of 30-60 of them (depends on the size and shape of your ribbon of course). So expect to pay ~$200 per iteration. Sorry, maybe more like 250-300+ due to the stiffener.
Can anyone in the UK solder some VSSOP-10 chips onto adapter boards? - Page 1
Forum section: electronics / general

author: Robert Smith Eco Warrior
author_rank: Regular Contributor
timestamp: April 14, 2021, 09:50:59 am
content: Hi All,My son and I are doing a project using some very small INA238 components. I think the 0.5mm leg spacing will possibly be beyond my hand soldering capability and I might possibly cook the device for too long while encasing all ten legs in one blob of solder.I have ordered the little chips and also some little adapter boards to bring the size upto 'normal' DIP size package.Can anyone in the UK help with soldering those together?

author: artag
author_rank: Super Contributor
timestamp: April 14, 2021, 04:09:57 pm
content: I've soldered 0.5mm before, but I'm probably not the best at it. Would probably help if you say whereabouts in the UK you are.You could try a local phone repair shop - if they do their own repairs they'll generally have the equipment and skill to do it.Alternatively, try a hackspace - most of them are reopening this week. At the London one we have an infra-red reflow oven that can be used (though ideally you'd want a stencil to apply solder paste).

author: jc101
author_rank: Frequent Contributor
timestamp: April 14, 2021, 05:32:18 pm
content: They don't look too bad, providing the adapter boards have sufficient exposed pad to solder them. I could probably do them under the microscope.

author: artag
author_rank: Super Contributor
timestamp: April 15, 2021, 01:22:25 pm
content: Try this methodhttps://imgur.com/gallery/Oci79zL

author: alanambrose
author_rank: Frequent Contributor
timestamp: April 21, 2021, 05:06:28 pm
content: Hi,It's actually pretty easy to do this yourself using some magnification. Also very easy to fix if you short some legs together. A long time ago I did find someone in Scotland who did this as a service and there's also some custom PCBs with stencils for this purpose if you look - from a Canadian company if memory serves.The Scotish co was:https://tirnaelectronics.co.uk/- I can't see they offer that service now, but maybe if you ask...The Canadian co is:http://www.proto-advantage.com/(not bad searching-fu considering it was 10 years ago)Roth and a million eBay sellers also sell adapter boards you can solder yourself.Look for 'SMD to DIP adaptor kit' or something similar.Alan

author: disillusionedrealist
author_rank: Newbie
timestamp: April 21, 2021, 07:36:48 pm
content: I could do these no problem if you decide not to. No charge other than postage.

author: Robert Smith Eco Warrior
author_rank: Regular Contributor
timestamp: May 06, 2021, 11:11:56 pm
content: Hi All,Thanks for the replies.I lost track of this thread but just found the 'Show new replies to your posts' button
Stencil alignment holes - bad idea? - Page 1
Forum section: electronics / general

author: phil from seattle
author_rank: Super Contributor
timestamp: May 04, 2021, 11:04:54 pm
content: I am working on a new board for my business and will make a few hand assembled prototypes using a stencil. I am adding a couple of alignment holes in the stencil by creating circular mask areas over holes in the PCB. The holes are 1mm so I can use a couple of pins to keep the mask aligned and in place while squeegeeing (if that is a real word) the solder paste. The holes serve no other purpose.The bad idea question is should I remove these alignment pads/holes for production when I go to contract assembly. I assume that solder paste over a hole will look odd and cause some consternation at the assembly house. Or is this common practice and nobody will care?

author: Mangozac
author_rank: Frequent Contributor
timestamp: May 05, 2021, 01:01:47 am
content: You would also have to ensure that the pins aren't in the path of the squeegee (both for hand and machine pasting). Otherwise when doing it by hand the pins will get in the way of the squeegee. If you went ahead and the machine pasted them you'll end up with paste and/or solder balls all around the SMT line.It sounds like a lot of screwing around for no good reason. Just check the alignment on each hand squeegeed board. Also, technically holes aren't perfect fiducials, since they aren't aligned to the pads perfectly (that would be an issue only if you were doing fine pitch though).

author: Rat_Patrol
author_rank: Frequent Contributor
timestamp: May 05, 2021, 01:41:03 pm
content: I would personally skip it.Unless you are needing PERFECT solder paste application for very small pitch parts, at which point you should have at least a manual solder paste stencil/pcb holder, close enough is close enough. The solder will find the pad and flow in, even if it wasn't applied perfectly over the pad.

author: fcb
author_rank: Super Contributor
timestamp: May 05, 2021, 02:40:42 pm
content: Alignment holes for dowels will be as accurate as drilling is... Just do a manual alignment of the stencil if you're only doing a few.
Has anyone bought from HKInventory or similar? - Page 1
Forum section: electronics / general

author: cmos2016
author_rank: Newbie
timestamp: April 28, 2021, 03:05:11 pm
content: Hi guys,I'm in the process of buying components for an assembly run, and ICs are very scarce or not available from typical distributors like Mouser and Digi-Key.I never tried to buy components from websites such as Hkinventory or similar, so I would really appreciate to read your experiences.I know that buying ICs from Chinese distributors is a risky business due to the possibility of receiving counterfeit chips.If you have a recommended trusted places for buying ICs please share them.Thank youcmos2016
Low cost equipment labels that survive outdoors? - Page 1
Forum section: electronics / general

author: e100
author_rank: Frequent Contributor
timestamp: April 10, 2021, 04:38:16 pm
content: Cutting strips from aluminum drinks cans and embossing with a ball point pen seems like the cheapest option for cables.Not sure what to use for a polycarbonate enclosure.

author: SilverSolder
author_rank: Super Contributor
timestamp: April 11, 2021, 12:23:16 am
content: The stick-on letters and numbers sold for post boxes? They are pretty durable...

author: Ian.M
author_rank: Super Contributor
timestamp: April 11, 2021, 12:49:40 am
content: Brother P-Touch label maker / label printer laminated label tapes are pretty durable if not subjected to serious abrasion. Even their red*on white tape is good for five or more years in a temperate climate exposed coastal location.* Many red, and orange dyes are notorious for poor UV resistance.

author: Rat_Patrol
author_rank: Frequent Contributor
timestamp: April 11, 2021, 12:54:33 am
content: Quote from: Ian.M on April 11, 2021, 12:49:40 amThis.We have had products in the field for over 10 years with Brother labels on them. They don't get direct sunlight, but all sorts of moisture/oil/grease, etc., as they are used on industrial engines.

author: SilverSolder
author_rank: Super Contributor
timestamp: April 16, 2021, 06:57:31 pm
content: Quote from: Alex Eisenhut on April 16, 2021, 05:40:40 pmMuch as I love those old Dymos (had one as a kid, LOL, these are old), the "ribbons" tend to lose their color over time when exposed to UV/rain outside.

author: Alex Eisenhut
author_rank: Super Contributor
timestamp: April 17, 2021, 01:30:23 am
content: https://www.gravotech.com/

author: Messtechniker
author_rank: Frequent Contributor
timestamp: April 17, 2021, 05:29:13 am
content: +1 for Brother P-Touch - specifically TZ 231 tape - in this application.

author: 1276-2449-1-ND
author_rank: Regular Contributor
timestamp: April 17, 2021, 03:33:26 pm
content: I usethesewith a good colour laser printer and cheap vinyl cutter to make instrument nameplates. They're available pre-cut so a vinyl cutter isn't necessary (I make custom shapes.)The "paper" is laser-printable vinyl and very sticky.

author: Lunasix
author_rank: Regular Contributor
timestamp: April 26, 2021, 08:22:34 pm
content: I confirm Brother P-Touch (and particularly Tze-M961). I use this tape on many products outdoor and they show no degradation even after years.
Assembling 4-layer PCBs with black solder mask - vendor suggestions? - Page 1
Forum section: electronics / general

author: ebastler
author_rank: Super Contributor
timestamp: April 26, 2021, 04:26:30 pm
content: I need to have some 4-layer boards made and populated, and would very much prefer to use black solder mask on them. That is a combination which JLCPCB does not support yet.(Their "SMT assembly capabilities" page is unclear on that, but the order page makes it clear that black solder mask is only supported when assembling 2-layer boards; 4-layer assembly is for green PCBs only. I did ask their support via email and they confirmed that JLCPCB mean that restriction.)Is there another low-cost service which offers SMT assembly for black 4-layer boards? I guess I know the answer -- "yes, but it will get quite a bit more expensive..." -- but thanks for any ideas!

author: Rat_Patrol
author_rank: Frequent Contributor
timestamp: April 26, 2021, 05:25:15 pm
content: Companies that I have used:PCBWay.comquickturnpcb.co.kr <-- South Korean.I'm 95% sure both offer what you want.

author: ebastler
author_rank: Super Contributor
timestamp: April 26, 2021, 09:35:17 pm
content: Thanks!As I had guessed, PCBWay is quite a bit more expensive than JLCPCB. For 10 pieces of a largish board, the assembly service is $300 vs. $100 (USD; service fee alone excluding parts cost). PCB manufacturing is $200 vs. $100. Quickturnpcb.co.kr calculates $600 for the PCBs alone; I did not explore their assembly pricing.Since this comes out of a hobby budget, the costs do matter to me. I would not balk at 30% more, but a factor of 2-3, or even a factor of 6, is hard to justify for me. Which, I guess, means that my PCBs will either be green, or I will have to populate them myself...

author: Bassman59
author_rank: Super Contributor
timestamp: April 27, 2021, 04:27:25 pm
content: Quote from: ebastler on April 26, 2021, 04:26:30 pmSeeed does not charge extra for non-green soldermask. I do not know how their assembly prices compare to JLCPCB.
Soldering BT module  - Page 1
Forum section: electronics / general

author: stoyanoff
author_rank: Contributor
timestamp: April 29, 2021, 03:32:38 pm
content: Greetings! I bought 2 samples ofLaird BL654PA(the long range version]. I want to make a simple board suitable for my needs and test the device. But I have a problem soldering the module to the board. The pads are so tiny. I`ve tried to apply tinol to all pads and use hot air from beneath the PCB - many pads don`t solder well. I don`t think stencil will help because of the size of the holes. How do you do this?Thanks!

author: richardmartino
author_rank: Newbie
timestamp: May 14, 2021, 10:14:31 pm
content: A stencil might actually be good. I don't think hot air would cut it on that land grid, I think something more uniform would be better like a hot plate or an oven.
Non-chinese PCB/PCBA manufacturing - Page 1
Forum section: electronics / general

author: rfleming
author_rank: Regular Contributor
timestamp: April 09, 2021, 02:29:56 am
content: Hi All,My boss and I are getting sick of the import taxes that the Chinese impose on Non-Chinese distributed parts when manufacturing. The political situation isn't the best either with Australia right now (where I am). Supplying a BOM with DigiKey part numbers is not as good as it used to be. While we have replaced many of items these days with LCSC parts when going into manufacturing, its still not the same.As such we have started looking else where. We are happy to have the boards made/populated anywhere, we don't particularly mind, and only ever go through runs of ~100 at a time because we do heaps of different products, though always almost a one off for different customers.When looking into the huge lists of manufacturers, don't many of them like the ones in South America simply act as a facilitator and simply get the boards made in China anyway?A few things to note based on suggestions:- We don't do any BGA stuff at this point in time, though could be a nice to have- We are looking for a manufacturer that takes roughly 6 weeks to do PCB+Assembly (assuming no stock issues), not quote 6 and take 8+ like PCB Way has started doing. And 2 weeks for blanks including shipping time.- We usually prototype our stuff first, so possible suggestions could be one place for PCBs only (usually in quantities of 5-10) and another for both when actual manufacturing- happy to pay the 30-40 US for DHL express shipping- Typically only do 1 side populating and 2-4 layer boards.- Boards can range from 0.8mm - 3.2mm thickness though typically only 1.6mm- Standard FR4 and sometimes flex.Any suggestions to help filter through the behemoth lists like ones on pcbdirectory.com would be awesome!Ryan.

author: Mangozac
author_rank: Frequent Contributor
timestamp: April 09, 2021, 06:48:51 am
content: My company does assembly here in Australia - I've just sent you a PMHaving just installed a full SMT line last year (on a budget too) I don't dissuade anybody else from doing this, but it's definitely not a trivial process. 1 year on an although we're pretty confident with it all now, there are still things we're learning and tweaking.

author: Rat_Patrol
author_rank: Frequent Contributor
timestamp: April 11, 2021, 12:52:34 am
content: I would say either setup your own production line (what we did) or try quickturnpcb in South Korea. We use them for our bare PCB fab, but they also do turnkey assembly.
Long and flexible KType thermocouples for oven characterization. - Page 1
Forum section: electronics / general

author: maxkunes
author_rank: Newbie
timestamp: May 12, 2021, 07:05:55 pm
content: Hi all,I'm looking for a longish (2m maybe) and very flexible K-type thermocouple for characterization my Chinese reflow oven. Its a conveyer belt, so right now I attach a long, but not very flexible, thermocouple to a test board and run it through while using a logging temp device. The only long enough thermocouple cable I have isn't flexible as much as I would like.Anyone know of a 1.5 to 2 m long silicone (not a requirement, but would be nice as it would be very flexible) K-type thermocouple that can withstand a few hundred C?

author: dzseki
author_rank: Frequent Contributor
timestamp: May 12, 2021, 07:10:55 pm
content: Since you appear to be in the US, Omega is your best bet. Thermocouples can be bought in virtually any length, and 0.5mm sheath diameter is rather common.

author: jmelson
author_rank: Super Contributor
timestamp: May 15, 2021, 01:34:45 am
content: Years ago, I managed to snag a 1000' reel of type E thermocouple extension wire on eBay. Yes, it is an oddball thermocouple, but most of the thermocouple controllers can be set for type E, you just have to get into a deep secret menu to change it. I specifically got micro-size wire so I could poke it into plated through holes in the boards.Actually, you can get thermocouple wire down to hair thin size if you need it to be really flexible and low thermal mass.Let me know if you want some of my type E wire.Jon

author: beanflying
author_rank: Super Contributor
timestamp: May 15, 2021, 01:45:00 am
content: Quote from: maxkunes on May 12, 2021, 07:05:55 pmThermocouples run couple specific wire cable to avoid adding extra couples wherever possible. Also Plugs and Sockets (not nesecerilly evilbay and aliexpress) are similarly material matched.The Omega resource section is great and well worth a trawlhttps://www.pyrosales.com.au/blog/thermocouple-information/thermocouple-cable-colour-charthttps://www.pyrosales.com.au/temperature-sensors/thermocouple-wire-and-cable

author: 48X24X48X
author_rank: Frequent Contributor
timestamp: May 15, 2021, 04:05:20 am
content: Omega's glass braided type-K GG-K-30-SLE would work great and withstand abuse over long term usage.

author: jonpaul
author_rank: Super Contributor
timestamp: May 15, 2021, 05:34:12 am
content: In 1980s we used Omega type K in 34 or 30 ga teflon or kynar insulation.The finished TCs are costly so we got the 100' or 1000' wire and rigged to spot wekd the couples.The yellow type K plugs are redily avaiable.We had 20-50 TCs in a large rack telecom terminal system.Check the max temp rating of each type of insulation.The braded TC wires are much thicker and need ony for mechanical damage protectionJon
JLC PCBA, Supply chain, IC shortage saga, just rant - Page 1
Forum section: electronics / general

author: nuclearcat
author_rank: Unknown
timestamp: April 01, 2021, 10:59:49 am
content: Just finished PCB and STM8S003 price jumped to sky.Ok, took a week, redesigned for STM8L051 that is a bit expensive before, but now cheaper aaaaand...(sorry for rant)

author: phil from seattle
author_rank: Super Contributor
timestamp: April 01, 2021, 04:27:30 pm
content: Quote from: nuclearcat on April 01, 2021, 10:59:49 amThat is JLCPCB in a nutshell - all their chips are subject to shortage. Basic parts are less likely, though. Their extended parts inventory is pretty fluid. To be fair to JLCPCB, they don't control the supply chain. That's why I make sure to have alternate parts for as many of the chips I use as possible. Obviously, you can't easily do that with a microcontroller.If you can find another source of the STM8, you could have them assemble without it and put it on yourself. For a one-off or small run, it's not so bad.

author: crossroad
author_rank: Contributor
timestamp: April 01, 2021, 05:34:22 pm
content: Yup I was lucky and stocked up a few hundred STM8S003/103 to cover my own prototyping needs back when they were sub $0.3I don't think redesigning boards to work around shortages is an effective strategy - things like this can happen

author: shadowpho
author_rank: Newbie
timestamp: April 01, 2021, 06:55:20 pm
content: Yeah. I made a small UPS device but by time I finished half the parts I picked went out of stock.... I might have to go with seeed, but they are 3x the price.

author: DIYGUY Chris
author_rank: Contributor
timestamp: April 01, 2021, 09:37:19 pm
content: I faced that as well but as it said in some previous comments I keep alternative for some components, not the case for MCUs but anyway I order the available parts for PCBA and for the missing parts I get them from other supplier (Farnell is my favorite place for parts) and I solder them myself.I saw that they are posting some news on them Facebook group about the possibility to support parts from Mouser and Digikey soon so I believe that this will sort out the process.

author: tszaboo
author_rank: Super Contributor
timestamp: April 01, 2021, 10:59:03 pm
content: STM32F103VCT6 is sold for 23 EUR.The more I look at this company, the more comedy gold it is.I made a PCBA that I wanted to order from them. It had a JST connector, they had it in their library.Next week, it is no longer in their library. Asked them a casual WTF question. Support promised that they take a look at it. Few days later they send an email, sorry, there is no stock. Maybe I can use this other connector with completely different pitch and TH instead of SMD (no I cant. I choose parts for reasons)I check LCSC, 50K on stock.They just don't care.

author: Mangozac
author_rank: Frequent Contributor
timestamp: April 04, 2021, 12:52:17 am
content: I'm so glad to have invested in my own SMT line (and now have just added a wave solder too!). Yes, chipageddon is still a headache but I can at least try to forecast and buy the raw component stocks I need ahead of schedule.
Assembly service in the UK, any recommendations? - Page 1
Forum section: electronics / general

author: simon104
author_rank: Newbie
timestamp: April 02, 2021, 12:50:41 pm
content: Within an hour or so of London would be best.Quantities are typically a few hundred, all surface mount except for connectors.ThanksSimon

author: artag
author_rank: Super Contributor
timestamp: April 02, 2021, 06:49:28 pm
content: HCD -https://www.hcduk.com

author: jc101
author_rank: Frequent Contributor
timestamp: April 02, 2021, 08:41:35 pm
content: Quote from: simon104 on April 02, 2021, 12:50:41 pmSoumac Assembly Services (https://www.soumac.co.uk) who are in Portsmouth. I've had them do single boards through to 100's, SMD and through hole connectors, plus double sided on occasion.

author: SMTech
author_rank: Frequent Contributor
timestamp: April 03, 2021, 11:04:07 am
content: I've visited Soumacs facility back when we were shopping for equipment, they are well setup for low volume work with multiple small machines in standalone and inline config.
Cheap PCB fabs who can do hard gold edge connectors - Page 1
Forum section: electronics / general

author: plazma
author_rank: Frequent Contributor
timestamp: September 06, 2019, 02:08:02 pm
content: I checked few places and only PCBway had an option for hard gold edge connector "gold fingers".They can even make rest of the board HASL.JLCPCB only had ENIG option for gold fingers. The rest of the board also have to be ENIG.ENIG is way more prone to wear than hard gold.Making some game carts.Have anyone found other places?

author: rea5245
author_rank: Frequent Contributor
timestamp: September 06, 2019, 02:22:37 pm
content: If you search onPCBShopper.com, you can specify gold fingers and you'll see several choices. However, you'll only see the manufacturers that offer gold fingers on their online quote form. Other manufacturers can do it, but you have to talk to a human <shudder!>. For example, I've had boards with gold fingers manufactured by Elecrow.Disclosure: I run PCBShopper.- Bob

author: xavier60
author_rank: Super Contributor
timestamp: April 01, 2021, 09:42:24 am
content: Has anyone actually ordered PCBs from PCBWay with hard gold fingers and HASL for the rest of the PCB?

author: Feynman
author_rank: Regular Contributor
timestamp: April 02, 2021, 02:02:41 pm
content: I think Eurocircuits can do this.

author: wraper
author_rank: Unknown
timestamp: April 02, 2021, 02:17:15 pm
content: Quote from: Feynman on April 02, 2021, 02:02:41 pmOf course they can do. But I don't think that someone who looks at JLCPCB will like their price.
Her "dream job" was to run a semiconductor company! - Page 1
Forum section: electronics / general

author: cdev
author_rank: Super Contributor
timestamp: March 29, 2021, 11:34:23 pm
content: Lisa Su, after spending a lot of time going to school, finally tackled her life's biggest challenge, refocusing a semiconductor company to "do what it does best" better.A few years later she has succeeded
Tape used for securing wires to PCBA? - Page 1
Forum section: electronics / general

author: semifnordic
author_rank: Newbie
timestamp: March 30, 2021, 07:29:58 pm
content: I'm working on a prosumer AV product design -- actually something already in production, but doing some design revisions. I'd like to make assembly a bit easier by giving the assembly techs some kind of tape that can be used to hold some fan and antenna wires in place and out of the way. Having taken apart various consumer electronics before, I've seen some sort of flexible, fabric-backed tape used for this purpose -- often for things like antenna leads in laptops and such -- but I have no idea what kind of tape it is. Something like Kapton would probably work, but it seems like a fabric-backed tape might offer more flexibility and easier installation. I have to imagine 3M's giant product list has something specifically for this, but I haven't found it.... Anyone know what kind of tape I'm talking about, or have a suggestion on something that might work? Thanks!

author: fcb
author_rank: Super Contributor
timestamp: March 30, 2021, 07:43:56 pm
content: Cloth tape. TESA make a black cloth tape (51608) - I've seen it called fleece tape also.

author: Dave8266
author_rank: Contributor
timestamp: March 31, 2021, 07:43:25 pm
content: Sounds useful to me too for taping up wiring harnesses.Googling TESA 51608, I get a number of references to 3M 1755. But while the 3M 1755 says harness bundling on the datasheet, it also says that it is a cloth backing which is covered with rubberized adhesive on BOTH sides. So I think this is a fundamentally different tape.(The TESA 51608 looks great... it just isn't stocked by any of the distributors my purchasing department has accounts with...)

author: thm_w
author_rank: Super Contributor
timestamp: March 31, 2021, 09:02:54 pm
content: Quote from: Dave8266 on March 31, 2021, 07:43:25 pmIts coated on both sides, but only sticks to itself.https://www.uline.ca/BL_6450/3M-1755-Cotton-Friction-Tape

author: semifnordic
author_rank: Newbie
timestamp: April 01, 2021, 03:03:18 pm
content: Thanks -- Tesa is a manufacturer I wasn't familiar with, and it looks like they have lots of niche products, good company to know. Too bad it's hard to find distributors for some of their stuff, I guess they mostly sell direct to large OEMs. Anyway, found a place selling 51608 and ordering a roll to try.

author: tooki
author_rank: Super Contributor
timestamp: April 10, 2021, 03:05:32 pm
content: Quote from: semifnordic on April 01, 2021, 03:03:18 pmBasically, Tesa is the 3M of adhesive tape in Europe. It’s omnipresent, and in many European languages, people say the equivalent of “tesa tape” where Americans say “scotch tape”.
black vinyl potting? - Page 1
Forum section: electronics / general

author: erikblue
author_rank: Newbie
timestamp: March 28, 2021, 06:13:42 pm
content: Hi, I'm doing a quick teardown and noticed a black, hard rubber potting. Seems similar to electrical tape (smells like it) so I'm assuming it is vinyl. Was able to get it off with boiling water. Does anyone know the basic tooling setup and cost for a solution like this? I assume is lower cost than epoxy, but I'm a complete nube to potting compounds. Any help or pointing me in the right direction is appreciated.Erik
Where to get small amounts of Manganin wire for shunts? - Page 1
Forum section: electronics / general

author: e100
author_rank: Frequent Contributor
timestamp: March 27, 2021, 03:56:11 am
content: Google turns up ready made shunts, bulk suppliers where the minimum order quantity is measured in kg, thin gauge "new old stock" from sellers in the Ukraine or wire that looks suspiciously like constantan.I just need a meter or so of 14 AWG to play around with making milliohm shunts like you would find in a multimeter.

author: bob91343
author_rank: Super Contributor
timestamp: March 27, 2021, 05:45:42 am
content: Cannibalize an old meter.

author: penfold
author_rank: Frequent Contributor
timestamp: March 27, 2021, 11:01:40 am
content: Which country are you in?https://www.wires.co.uksell it, so I guess it's not all that niche

author: e100
author_rank: Frequent Contributor
timestamp: March 27, 2021, 02:41:21 pm
content: Quote from: penfold on March 27, 2021, 11:01:40 amThanks, I'm in Aus.

author: bob91343
author_rank: Super Contributor
timestamp: March 27, 2021, 05:05:42 pm
content: Austria or Australia?

author: ledtester
author_rank: Super Contributor
timestamp: March 28, 2021, 12:54:15 am
content: Aliexpress:-- 1m various gauges:https://www.aliexpress.com/item/1005002073502029.html-- 32 AWG:https://www.aliexpress.com/item/32858623659.html-- 10m various gauges:https://www.aliexpress.com/item/32821451063.htmlI would contact these vendors to see if they can hook you up with what you're looking for.I searched for "constantan".

author: e100
author_rank: Frequent Contributor
timestamp: March 28, 2021, 02:20:17 am
content: Quote from: bob91343 on March 27, 2021, 05:05:42 pmAustralia.
Potting compounds used in permanently wet areas?   - Page 1
Forum section: electronics / general

author: e100
author_rank: Frequent Contributor
timestamp: March 27, 2021, 07:40:55 am
content: Not many things stick to PVC cable insulation so I'm curious as to what manufacturers use for things like electric toothbrush chargers that are powered from the mains yet typically sit next to the sink and therefore spend a large proportion of the day in damp or wet conditions.Presumably the insulation has to be super reliable and low leakage in order to get approval for use in this type of product.

author: Ian.M
author_rank: Super Contributor
timestamp: March 27, 2021, 08:37:58 am
content: Its all a matter of the surface preparation of the PVC. If you lightly abrade, solvent degrease (to remove contamination and free plasticizer from the surface) then lightly treat the surface with a flame or plasma to oxidize the surface PVC molecules, (not for long enough to melt the surface), Epoxy will bond very well to PVC. Properly prepared, the PVC substrate will fail before the Epoxy to PVC bond.There are also commercially available liquid adhesion promoters for various potting compounds and substrates - contact your potting compound manufacturer's technical department for advice.
UV resistant plastics other than acrylic, polycarbonate, PVC and ABS - Page 1
Forum section: electronics / general

author: e100
author_rank: Frequent Contributor
timestamp: March 24, 2021, 08:17:23 am
content: Dedicated project boxes seem to be priced in ways that make no sense and in my quest to do things on the cheap I found some good looking food containers that are made from transparent SAN (Styrene acrylonitrile resin).https://en.wikipedia.org/wiki/Styrene-acrylonitrile_resin.UV stability information seems a big vague and doing an actual outdoors test will take literally months of just waiting.So has anyone had any success with any of the newer engineering plastics such as SAN or are we forever stuck with acrylic, polycarbonate, PVC and ABS and the prices that go with these?

author: tszaboo
author_rank: Super Contributor
timestamp: March 24, 2021, 12:13:20 pm
content: You just have look for a material plastic, or enclosure with UL 746C tests.Apparently, this is not as simple as selecting a type plastic, as there are other factors to this. Like additives, color, surface treatment and so on.

author: nuclearcat
author_rank: Unknown
timestamp: March 24, 2021, 12:23:02 pm
content: Quote from: e100 on March 24, 2021, 08:17:23 amYou can accelerate aging/destruction by using dedicated UV lamps. (especially UV-C)

author: kosine
author_rank: Regular Contributor
timestamp: March 24, 2021, 01:33:03 pm
content: https://omnexus.specialchem.com/polymer-properties/properties/uv-light-resistanceSAN is relatively cheap and can be UV stabilized for outdoor applications, as can most plastics, but the containers you have are probably not. Acrylic/Perpsex/Plexiglass (PMMA) is probably your best bet. PVC is also fairly good for UV resistance, which is why it's used for drainpipes and guttering.ABS is more common, but will gradually yellow and go brittle in UV, and PC is not that great outdoors. (It's also more expensive.)Sadly there isn't anything better unless you start looking at quite exotic materials, and they get very pricey. I've used nylon 11 (paid about £12 per kg) which is pretty good in UV (it's used to make specialist cable ties for solar farms), and I've also dabbled with the even more expensive fluoropolymers - specifically PDVF (5kg of it cost over £250!!). Some of these fluoropolymers (like FEP) are almost transparent to UV so largely unaffected by it, but you can be paying up to £100 per kg for it.Acrylic at £2-3 per kg is a bargain by comparison. It's also easy to cut and drill.
JLCPCB Assembly Site Not Working - Page 1
Forum section: electronics / general

author: Miti
author_rank: Super Contributor
timestamp: March 21, 2021, 11:24:09 pm
content: I'm trying to quote a board to assemble with JLC. I can load the Gerber files, I can select assembly, select the side that I want to assemble, etc, but when I click confirm, it doesn't go to the next page to load the BOM and pick and place file. I tried Chrome and Firefox with the same result. Does it work for you?Cheers,Miti

author: phil from seattle
author_rank: Super Contributor
timestamp: March 22, 2021, 12:01:07 am
content: give it some time. their web site isn't the most stable. maybe try again later.

author: Miti
author_rank: Super Contributor
timestamp: March 22, 2021, 11:24:43 am
content: Still not working...

author: mon2
author_rank: Frequent Contributor
timestamp: March 22, 2021, 03:19:53 pm
content: Their service has been quite good in the past. Only one sort of a screw up with our gerbers.Consider to ping them directly with your RFQ:support@jlcpcb.com

author: DIYGUY Chris
author_rank: Contributor
timestamp: March 22, 2021, 08:29:14 pm
content: I just used it and it works fine for me, clear the cache of your browser and try again!

author: Miti
author_rank: Super Contributor
timestamp: March 22, 2021, 10:52:52 pm
content: Still no luck. I tried on two computers with three browsers and I get the same result.Chrome and Firefox on a Linux machine, the one I used to order before, and Chrome and IE on a Windows machine.

author: Miti
author_rank: Super Contributor
timestamp: March 23, 2021, 01:05:59 am
content: Mistery solved. They added a Layer Stackup which wasn't there before and that is mandatory. If you don't fill that, it simply doesn't do anything.
0402 chip resistor problem - Page 1
Forum section: electronics / general

author: Aleksei
author_rank: Newbie
timestamp: March 18, 2021, 11:56:22 am
content: I have a problem with 0402 chip-resistors.When the top tape is detached from paper tape, the resistor jumps out or flips over.PnP machine doest pick component.Adhesive (glue) between the top tape and the paper tape got caught on the resistor, i think.OrStatic electricity attracts the resistor to the top tape...I dont have any ideasDoes anyone have a same problem?PS. No problem with the 0402 chip-capacitor.

author: SMTech
author_rank: Frequent Contributor
timestamp: March 18, 2021, 01:51:23 pm
content: I've not seen a definitive reason for this happening but I doubt it is static or glue. The best (and most common) suggestion I have seen is moisture, so you could try sticking the reels that have this problem in a food dehydrator or filament dryer, or storing it in a sealed box with some fresh desiccant bags.

author: Rat_Patrol
author_rank: Frequent Contributor
timestamp: March 18, 2021, 06:14:41 pm
content: Curious what brand resistors you are running.I've run a LOT of Panasonic chip resistor reels w/o any kind of issue, but never smaller than 0805.

author: Aleksei
author_rank: Newbie
timestamp: March 19, 2021, 05:44:12 am
content: Quote from: SMTech on March 18, 2021, 01:51:23 pmWe store the components in a dry storage cabinet.Quote from: SMTech on March 18, 2021, 01:51:23 pmI think, i'm trying this!Quote from: Rat_Patrol on March 18, 2021, 06:14:41 pmFaithful LinkToday i tooke a photo. It's not good quality, but i saw the samples are different.I haven't problem with top sample - it's matte.I have problem with bottom sample - it's glossy.I think it's realy glue or somthinge else

author: jmelson
author_rank: Super Contributor
timestamp: March 19, 2021, 08:51:59 pm
content: Are you actually running this with the feeder top cover up, like in the middle photo? There is nothing to keep the component tape from bouncing as the cover tape is peeled! I would definitely expect this to happen if you are trying to run it like that middle picture.That cover is supposed to hold the component tape down flat, and peel the cover tape at one specific spot.Jon

author: Siwastaja
author_rank: Super Contributor
timestamp: March 20, 2021, 09:28:21 am
content: Indeed, any bouncing of the tape is the likely culprit. It happens easily, it doesn't need to bounce more than a few hundred µm. The feeder design must transfer the tape smoothly without any up-down motion.

author: Aleksei
author_rank: Newbie
timestamp: March 21, 2021, 06:06:59 am
content: Quote from: jmelson on March 19, 2021, 08:51:59 pmNo! I opened top cover to take a photo, and show you chip-resistor glue on a top tape.I tooke a new photo with closed top cover feeder on a PnP machine camera.
Solder bridge jumpers - pre-configured? - Page 1
Forum section: electronics / general

author: phil from seattle
author_rank: Super Contributor
timestamp: March 20, 2021, 09:08:00 pm
content: I have been using solder bridge jumpers on PCBs for a fairly long time. For the default setting, I route a trace and the customer has to cut it to make a bridge for the other option. I would like to get away from a trace for the default and have the assembled board use an actual solder bridge for the default.I have seen this on some boards (STM32 Nucleo boards, for example. How is this specified to an SMD assembler - via a soldermask layer entry that covers the two pads you want bridged? (I guess technically, it is a soldermask opening/hole...) Are there any issues I should be aware of? Make it extra large to ensure lots of solder paste gets laid down?

author: PeteH
author_rank: Unknown
timestamp: March 20, 2021, 09:09:53 pm
content: Why not zero ohm resistors as a BOM option?

author: phil from seattle
author_rank: Super Contributor
timestamp: March 20, 2021, 09:20:55 pm
content: It's a possibility but with solder you can just use an iron and wick to remove it. Resistors are little harder to remove. Trying to keep the intimidation factor as low as possible for my customers.

author: PeteH
author_rank: Unknown
timestamp: March 20, 2021, 09:33:24 pm
content: You could design the shorts as a baseball diamond shaped pad (arrow like)... And perhaps oversized paste mask opening, even with some small "wicking webs" to pull the paste into the pad area... Not sure how reliable that is.Small 0402s with good thermal relief are pretty easy to remove with a ball of solder on the iron tip.

author: SMTech
author_rank: Frequent Contributor
timestamp: March 20, 2021, 10:51:53 pm
content: We used to have two pads with a narrow gap that need linking to program the device and then wicking off later. Despite those processes both happening in house we found it was in fact quite tricky to successfully wick off that link and not leave a basically invisible trace reliably so I would say be careful not to make the gap too small or perhaps don't use straight edges.I would agree a small zero ohm link such as 0402 is pretty easy to remove and doesn't need you to experiment with a custom pad gap and stencil adjustments - you already know what works there. I would think you would need a solder deposit across both pads plus some extra to get a reliable link with paste to stop it turning into two big lumps.