hybridfree/eevblog-posts huggingface dataset:
Cheap Chineese 150$ PCB CNC millers. - Page 1
Forum section: electronics / projects

author: BrianHG
author_rank: Super Contributor
timestamp: January 22, 2017, 12:07:37 am
content: Has anyone had experience with those 150$ price ranged PCB milling machines. I'm interested in milling 2 sided copper clad boards + hole drilling.Which model & make did you choose. How easy was it to import gerbers & align the PCB when flipping it over and changing to the drill bits?

author: BrianHG
author_rank: Super Contributor
timestamp: January 22, 2017, 02:09:28 am
content: Machines similar to these:https://www.aliexpress.com/item/Freeship-DHL-PCB-Milling-Machine-arduino-CNC-DIY-CNC-Wood-Carving-Mini-Engraving-Machine-PVC-Mill/32661950881.html?spm=2114.10010108.1000014.6.RFr23H&scm=1007.13338.50051.0&pvid=678f66ac-bb08-4af2-b3db-462779fc6024&tpp=1https://www.aliexpress.com/item/PCB-milling-machine-CNC-2020B-DIY-cnc-wood-carving-machine-mini-engraving-machine-3050114C/32261769903.html?spm=2114.10010108.1000014.12.HPhtfr&scm=1007.13338.50051.0&pvid=281f2a09-1379-4d91-a694-3e222fd7d3ad&tpp=1

author: thm_w
author_rank: Super Contributor
timestamp: January 24, 2017, 12:00:19 am
content: Thats not $150, its $325 to $400. Although I do see some for $240 after shipping as well (don't forget import duties you will be paying to DHL).Machine looks decent enough if you want to learn about CNC and do some engraving for fun.If you want quality 2 layer circuit boards without pulling your hair out, look elsewhere.I don't see supplied workholding. You can use double-sided tape and a spoilboard for example. Flipping over is not too bad if you drill some registration holes and then re-align with those.Getting the height of the engraving bit correct can be a pain (assuming the surface is level).
Cheap chinese Pfets – too good to be true? - Page 1
Forum section: electronics / projects

author: 3dgeo
author_rank: Frequent Contributor
timestamp: September 01, 2019, 06:09:50 pm
content: Hello,I foundBRCS4953DMFonLCSC. Those parts are very cheap compared to similar known names equivalent. Too good to be true?It will have to switch up to 900mA@<600Hz (high side, 3.3V logic).I will test them eventually alongside known brands, but just wanted to know community opinion.
Cheap Compact Battery-Operated Programmable Outdoor Laser Projector - Page 1
Forum section: electronics / projects

author: Urger333
author_rank: Newbie
timestamp: January 16, 2021, 09:55:12 am
content: Hi everyone,I want to create laser shows for my country property. I want to be able to project onto a building from about 30-50m away. I want the projector to be chargeable/ battery option and as cheap as possible - pref under $100. I want it to be programmable - i.e. I want to be able to create my own messages and animations. Also, it would be good if it was compact.If there isn't anything like this on the market, I'd be happy to make one if there is a DIY option, maybe using Arduino or a Raspberry Pi.Thanks for any tips!
Cheap, easy, handheld RF scalar network analyzer - Page 1
Forum section: electronics / projects

author: trberger
author_rank: Newbie
timestamp: February 13, 2017, 01:17:30 am
content: HiI just posted Yana (Yet Another Network Analyzer) in the PHSNA group. Look in the Filesfor Yana. (Message #3192)https://groups.yahoo.com/neo/groups/PHSNA/conversations/messagesCheap, easy to duplicate, handheld portable SNA. Cost about $40. Follows the PHSNA designexcept a small TFT and Nano replace a computer. Detailed build instructions with experimentsto follow.For those still looking.regardstom.k1trb

author: gerryk
author_rank: Newbie
timestamp: February 13, 2017, 10:27:14 am
content: Nice... similar in design to Duwayne's (KV4QB) SNA Jr.http://kv4qb.blogspot.ie/2016/06/sna-jr-ii-update-two.html?m=1

author: Simon
author_rank: Unknown
timestamp: February 13, 2017, 06:20:43 pm
content: Please don't double post, it's very annoying. Topic closed
Cheap filter profile(r?)  - Page 1
Forum section: electronics / projects

author: BiOzZ
author_rank: Regular Contributor
timestamp: January 27, 2014, 07:24:55 am
content: So i dont own a spectrum analyzer, the sweep/scope method is too hard to control and capture and i have lots of left over components that i believe i can turn in to a fairly simple sweep/sample filter profiler for a series of filters that are < 25mhzi came up with this very rough layout (attached)its basically a DDS generator > LC > AC Bias > 350MHZ high precision opamps (i have a lot of them but there in TSSOP packages and right now i cant be bothered to look them up for the exact part number) > FILTER UNDER TEST > peak detecting circuit that's MCU resettable > ADS7924 12 bit 100khz ADC on a REF5020 2.048v ref > NXP 100MHZ M3 > USB > Matlabi will be making a proper 4 layer PCB this timeits simple, slow, dirt cheap with the parts that i have and will give me a basic understanding of many different filters that i use or made to than take to a proper spectrum analyzer after i think it works with thisthe problem here is i dont know much about tracking generators and how they work so before i continue on i would want to be sure that it worksit would set an sine wave at n-hz than sample and hold its peak, read it from the ADC and store, reset the peak detector, loop()and yes as im typing this i realize that R4 has to go!oh yeah before i forget to weed some people outIts only a basic layout, needs values and breadbording, im somewhat aware that the AD9835 needs more than just the output to run, power for exampleEDIT: why cant i just rely on math for < 50mhz filters? many many reasons but primarily because what i really want to spend time and effort testing are dynamic or digitally adjustable filters im working on for a school project

author: KJDS
author_rank: Super Contributor
timestamp: January 27, 2014, 08:31:24 am
content: You'll suffer from harmonics on the signal source messing with the measurement when you have high rejection.it is also far easier to tune a filter when measuring its return loss.

author: BiOzZ
author_rank: Regular Contributor
timestamp: January 27, 2014, 04:16:52 pm
content: Quote from: KJDS on January 27, 2014, 08:31:24 amWhat would be a workarround?i dont exactly see why i would i have built up similar circuits using AD9850 and the FFT of the output when AC coupled properly is generally very cleanand i dont need it for tuning a filter but for mutable other aspects of the filters like to set up an equation based on what is digitally sent to them ... this is the only reason im using this instead of other methodsbut as i often run in to on this site thats not the purpose of this post

author: KJDS
author_rank: Super Contributor
timestamp: January 27, 2014, 06:33:54 pm
content: Imagine testing a 15MHz bandpass filter. It has better than 60dB rejection below 10MHz and above 20MHzAt 5MHz your third harmonic, which is perhaps 50dB down is going straight through your passband into your detector. At 7.5MHz, your second harmonic is also going straight through your passband into your detector, so you have a significant limit to dynamic range.
cheap general purpose field detection probes (spectrum analyzer/oscope add ons) - Page 1
Forum section: electronics / projects

author: sarepairman2
author_rank: Frequent Contributor
timestamp: July 07, 2015, 04:56:46 am
content: is there any kind of probes I am missing?I intend to make hardline loop probes. I made a magnetic toroid based one, the two jim williams ones (slotted and figure 8 coil "highly discriminative" one, a 1 inch square loop probe, and a low Z (2 parallel with 50 ohm) 6 foot "esd" detector antenna.I am planning on making the coaxial hardline based probes.http://koti.kapsi.fi/jahonen/Electronics/Stuff/EMI_Sniffer_EDNMAG.pdf- jim williams onehttp://emcesd.com/tt070100.htm- esd detector onehttp://emcesd.com/tt080699.htm-square loophttp://www.interferencetechnology.com/wp-content/uploads/2012/04/Wyatt_NA_DDG12.pdf- current probeI have a proper tektronix clip on current probe, so I don't wanna make one of those. the one using 0.05mm wire in the figure 8 was kinda annoying to figure out how to make, I ended up using two drill bits and a 0.00something mm shim in a vice to make it..Other then the loop probes that are made using hardline, is there anything else that is useful?Are there like microwave horns or such that can be made of copper sheet/etc? I have a 22GHz spectrum analyzer and is quite fun to build these not really calibrated "diagnostic" tools. I am looking for stuff thats useful in a fairly wide band, I don't want to make "tuned" antennas until I have a good use for them.
Cheap gold plating - Page 1
Forum section: electronics / projects

author: ezalys
author_rank: Frequent Contributor
timestamp: June 08, 2018, 06:18:17 pm
content: After calling around a bit around my area, it seems like the cheapest I can get a part gold plated for is in the several hundreds of dollars. This is way too much for a hobby project. I just want some custom probes plated. Is there anyone anywhere that you've had good luck with for gold plating small parts? I don't mind sending my parts to china and waiting for them to come back, if my best bet is looking overseas. I also absolutely do NOT want to do the process at home... so I'd prefer to send the part out. Any ideas? Specifically I want hard gold with a nickel strike layer over phosphor bronze base metal.

author: woodchips
author_rank: Frequent Contributor
timestamp: June 08, 2018, 06:45:24 pm
content: Talk to your local PCB supplier, they gold plate connector fingers all the time.

author: jmelson
author_rank: Super Contributor
timestamp: June 08, 2018, 07:11:36 pm
content: You can buy "gold plating pens" on eBay and similar. You get a thing that holds a couple AA batteries, and a brush, and there's a wire with a clip on it. You put in the battery(s) clip the clip to the item, dip the brush in some deep blue solution, and wipe on the item. Repeat until desired gold finish is achieved. The blue stuff contains cyanide, so work carefully with it.You can also put a barrier layer like Nickel under the gold, depending on the base metal.Jon

author: wasyoungonce
author_rank: Frequent Contributor
timestamp: June 09, 2018, 03:08:07 am
content: If you smell almonds....straight to ED dept!

author: helius
author_rank: Super Contributor
timestamp: June 09, 2018, 04:57:31 am
content: There's a lot to learn about in this field... check out the forums atwww.finishing.com, it's a pretty good source for domain knowledge.
Cheap grayscale OLEDs? - Page 1
Forum section: electronics / projects

author: anfang
author_rank: Regular Contributor
timestamp: September 24, 2016, 02:03:34 am
content: Are there cheap (< 10 EUR) OLED displays that can display grays? 4 shades of gray would be enough, 16 would be plenty.All I can find on ebay and aliexpress are either monochrome displays (about 3 EUR) or 65k color displays (around 12 EUR). Did the OLED technology skip the monochrome step?
Cheap homemade test points - Page 1
Forum section: electronics / projects

author: gibbled
author_rank: Regular Contributor
timestamp: January 19, 2019, 12:46:02 am
content: I found "Glass seed beads" at the local dollar store a few days ago. $3 for three or four ounces of the little things.

author: intabits
author_rank: Frequent Contributor
timestamp: January 19, 2019, 12:47:58 am
content: Neat!Do they solder easily?

author: tautech
author_rank: Super Contributor
timestamp: January 19, 2019, 01:07:47 am
content: And it's a lot less hassle to use off the shelf SMD onesandyou can easily remove them from prototypes when testing is done to replace them with a zero ohm resistor. Lower profile too so to act less as an antenna.Scope probes can easy get onto 0805 SMD, no problem.I split 100 with a buddy and just recycle those I've used.https://www.digikey.com/product-detail/en/keystone-electronics/5015/36-5015CT-ND/278886

author: gibbled
author_rank: Regular Contributor
timestamp: January 19, 2019, 01:23:09 am
content: I forgot to mention that I formed the wire loops in #24 solid from old cat3 cable.

author: Doctorandus_P
author_rank: Super Contributor
timestamp: January 20, 2019, 01:06:16 am
content: Did I understand correctly that you made these yourself from glass beads and stripped CAT5 wire?Oops, you used cat3.I bought a bag of 100 for EUR2.20 from ali.Pre-made and they look gold plated, or at least yellow shiny instead of red copper which will probably oxidize more readily.https://www.aliexpress.com/wholesale?SearchText=pcb+board+bead+test+pointAnother tip:Sometimes I use a small resistor as a shunt for current measurement and I solder them directly on the target (vero board) PCB while designing. I also solder a 2 pin header with 0.71mm square pins parralell to that resistor.Those are an easy attachment for "dupont" style cables (easy for breadboard, make an adapter for your multimeter).This makes for a reliable connection, with no chance of temporarily opening the circuit because of a bad test clip.And when not in use, or when there is doubt the shunt resistor may influence your circit you can put a standard jumper over it to short it.Another tip:On a lot of the experimental designs I make I make a large ground loop from standard 2.5qmm copper stripped installation wire.Those are very easily recognized as a GND connecton to connect your oscilloscope GND probe and various GND clips for other measurement equipment.

author: cdev
author_rank: Super Contributor
timestamp: January 20, 2019, 07:06:01 pm
content: Thats areally good idea, thank you!I'm going to get some right now..maybe even get them by color so as to always have enough of needed colors to keep my color coding consistent. They also could go around wires. Nice and brightly colored and no way to miss them.I'm not getting younger, unfortunately, and I find stuff like that helps a lot. It makes all the difference for my understanding stuff.
cheap IR thermometers  - Page 1
Forum section: electronics / projects

author: JBeale
author_rank: Frequent Contributor
timestamp: March 18, 2016, 08:52:06 pm
content: I see that you can now buy a handheld IR thermometer for under $10 on Amazon, for example:http://www.amazon.com/Digital-Infrared-Thermometer-Temperature-Pyrometer/dp/B013Z8NHCGI bought a slightly more expensive $18 version which works perfectly well. Haven't taken it apart yet but I can see they are using a dime-sized IR fresnel lens to achieve the 12:1 ratio focusing onto some internal thermal sensor.Does anyone know if the thermal sensing module by itself (without the laser pointer, LCD display etc.) is available, for example with a serial output? I would think such a thing should exist, but I haven't seen it anywhere.Or maybe what I want is the TI TMP007 breakout board likehttps://www.adafruit.com/products/2023plus an IR lens fromhttp://www.glolab.com/pirparts/pirparts.html?

author: TonyD
author_rank: Contributor
timestamp: March 26, 2016, 12:29:15 am
content: I got a similar model a few years back.For what I remember it just had a simple thermopile sensor with analogue output.Any particular reason you need one with a serial output? (other than its just a cool thing to try out)

author: bhalakiya
author_rank: Newbie
timestamp: April 09, 2016, 05:31:45 pm
content: What about MLX90614!!!It has both interfaces PWM(Analog) as well as I2C

author: Raj
author_rank: Frequent Contributor
timestamp: May 13, 2016, 07:20:31 am
content: I am also working on same stuff... (i'll be using mlx90614)(Just having a display dilemma ,can't decide what display to use with atmega8 qfn just can't find a display small enough)btw here's some suggestionsmlx90614 for single pointmlx90621 for camera
Cheap lamp with magnification and awesome light. - Page 1
Forum section: electronics / projects

author: Mikey
author_rank: Regular Contributor
timestamp: September 22, 2012, 05:04:33 pm
content: Lamp:http://www.ebay.co.uk/itm/110951694009Light:http://dx.com/p/t10-39-led-white-light-car-angel-eye-120mm-diameter-25522All you need to do is to do is to remove the original socket for the light bulb, attach the wires to the led ring, followed by mounting the ring with hot glue to the case.And the result is pretty good

author: MikeK
author_rank: Super Contributor
timestamp: September 23, 2012, 02:02:19 am
content: How are you powering a 12V LED ring from mains voltage?

author: ablacon64
author_rank: Frequent Contributor
timestamp: September 23, 2012, 02:16:55 am
content: Interesting! How much magnifying? 5X? 10X?

author: T4P
author_rank: Super Contributor
timestamp: September 23, 2012, 07:26:35 am
content: Quote from: MikeK on September 23, 2012, 02:02:19 amHack in a DC jack@Mikey, What's the size of the LEDs?

author: Mikey
author_rank: Regular Contributor
timestamp: September 23, 2012, 08:58:39 am
content: Quote from: MikeK on September 23, 2012, 02:02:19 amNo, or yes... Powering them from mains through a switch mode power supply.Quote from: ablacon64 on September 23, 2012, 02:16:55 amNo idea, but it is defiantly not 10xQuote from: T4P on September 23, 2012, 07:26:35 amI have no idea about that either, deal extreme didn't really provide any specs besides voltage and weight...

author: T4P
author_rank: Super Contributor
timestamp: September 23, 2012, 11:27:26 am
content: i buy from DX most of the time and i'm pretty bummed out the sellers didn't provide the size of the LEDs (eg: 5050/3528)measure with a calliper and tell me thanks (5mmx5mm or 3.5mmx2.8mm)
Cheap, large, low-tech flex PCB - Page 1
Forum section: electronics / projects

author: Renate
author_rank: Super Contributor
timestamp: January 13, 2020, 05:54:02 pm
content: I'm looking to build a sensor using a flex PCB.The size is around 75mm x 300mm (3" x 12") plus a tail.I see plenty of options for polyimide, but it's thin and expensive.I was looking for more the crappy stuff that they make PC keyboards out of.That's tough, thick, translucent with tinned tracks and carbon globs. I don't need any carbon globs.This is so low tech that if I had the single sided material I could tape out the design myself, although obviously I'd prefer somebody to knock me out a half dozen.Does anybody have any leads on this, or even what it's called?

author: jmelson
author_rank: Super Contributor
timestamp: January 13, 2020, 08:56:38 pm
content: There are devices like the Cricut, that can cut out paper and plastic for scrapbooking (a fad, at least in the US). You can getstuff that has copper foil stuck to vinyl plastic, cut it with the Cricut and peel the unwanted parts of the copper.I never tried this, but was looking at this for a project for wearable LED systems.Jon

author: artag
author_rank: Super Contributor
timestamp: January 13, 2020, 10:23:41 pm
content: I don't know the answer, though I may need something similar myself.I intend to research FFS and FPS - those thin laminated circuits that are commonly used as ribbon cable. If I can't find a suitable one off the shelf it's possible the manufacturers will do custom pieces more cheaply than polyamide.

author: dmendesf
author_rank: Frequent Contributor
timestamp: January 14, 2020, 03:55:30 am
content: Those are PET based:https://www.kingleytech.com/show-66718.htmlYou cannot solder it because it melts.

author: Renate
author_rank: Super Contributor
timestamp: January 14, 2020, 04:16:36 am
content: Quote from: dmendesf on January 14, 2020, 03:55:30 amHmm, that looks like it would be really cheap if I wanted a million.I think the whole silkscreen bit would be expensive for a few though.
Cheap Laser Printer for Making PCB transfers - Page 1
Forum section: electronics / projects

author: daveyk
author_rank: Frequent Contributor
timestamp: March 29, 2020, 06:16:10 pm
content: Would this LASER printer work okay for making PCB transfer papers?https://www.ebay.com/itm/NEW-HP-Laser-Jet-Pro-M15a-Monochrome-Compact-Black-Mono-Laser-Printer-With-Toner/114102661449?epid=16035561397&hash=item1a910c7149:g:Bw8AAOSwb0BePGgNI want to make some of the Carlson SMT PCB designs.It's like $60!!Dave

author: Wimberleytech
author_rank: Super Contributor
timestamp: March 29, 2020, 11:15:33 pm
content: Quote from: daveyk on March 29, 2020, 06:16:10 pmI don't own it, so I cannot say for certain. However, I have the HP P1102W and have used it for a long time making PCBs. I would advise using HP Toner for best results. Just recently, I used a non HP toner and had good results but I wonder about quality control...will the next cartridge work as well. I would be confident in HP QC. The key to a good result is in the toner. HP and Brother toners have proven themselves to me.
cheap lifi detector? - Page 1
Forum section: electronics / projects

author: CopperCone
author_rank: Super Contributor
timestamp: September 22, 2017, 10:27:07 pm
content: I was curous about being able to identify, but not demodulate wifi.What kind of diode would be suitable for this?I have an OSD3E diode, which has a rise time of 7ms to a 50 ohm load. If irradiated by a lifi transitter, would it show up modulation on an oscilloscope or spectrum analyzer?
cheap magnets? - Page 1
Forum section: electronics / projects

author: vivi-d
author_rank: Regular Contributor
timestamp: January 19, 2021, 03:27:28 pm
content: Howdy!I'm working on building a small vertical wind turbine. I thought I would be cool to have the rotor suspended by a magnetic halbach array to reduce friction. I was thinking of using washers that have been magnatized for this part, since they are pretty cheap.My question is what kind of washers (what kind of metal) should I be looking for? I've tried magnetizing a few washers but could not make them permanent magnets.The electricity producing magnets would of course be made of higher performing magnets...

author: Conrad Hoffman
author_rank: Super Contributor
timestamp: January 19, 2021, 07:55:38 pm
content: IMO, no iron washer will become a decent permanent magnet. Neos are so cheap you should just buy a bunch.
Cheap material, thermally conductive, electrical insulator, heat resistant 60C? - Page 1
Forum section: electronics / projects

author: Nuttyboltz545
author_rank: Newbie
timestamp: October 14, 2022, 10:37:28 pm
content: Hi I am looking for a material with the above properties, I am leaning toward the material used for common thermal-pads however I do not know the name of this material, nor where to buy it on a large roll.The material needs to be cheap as each product will use a large amount, ideally I want the roll to be 300-500mm wide.Any Ideas?

author: Benta
author_rank: Super Contributor
timestamp: October 14, 2022, 10:54:59 pm
content: 3M is probably the best source:https://www.3m.com/3M/en_US/p/d/b10469519/Otherwise search for:"thermally conductive silicone sheet"

author: jpanhalt
author_rank: Super Contributor
timestamp: October 15, 2022, 12:01:04 am
content: BN epoxy (https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6723785/)BN = boron nitrideSometimes called white graphite is it is slippery like graphite. You could make your own paste.

author: Phoenix
author_rank: Frequent Contributor
timestamp: October 15, 2022, 12:07:14 am
content: Berquist make the SIL PAD, they are ubiquitous in electronics... Perhaps you can also find cheap no name versions.https://www.henkel-adhesives.com/us/en/products/thermal-management-materials.html

author: Nuttyboltz545
author_rank: Newbie
timestamp: October 15, 2022, 12:23:20 am
content: The legit stuff is pretty pricey, alibaba grade would be good for my application though.Thanks

author: Nuttyboltz545
author_rank: Newbie
timestamp: October 15, 2022, 01:02:55 am
content: I am more after the foam style material with some thickness, the product is a heated pad for an animal, so I want to keep the nichrome wires a distance away from the skin, it just needs to conduct heat well for a foam.I have seen pads like this in products I have dismantled, never a large one though, really anything with half decent thermal properties will do, just need decent conduction on a 3-4mm thick pad

author: pqass
author_rank: Super Contributor
timestamp: October 15, 2022, 01:11:09 am
content: I was going to suggest Kapton (polyimide); comes in sheets or tape of various widths. Expense is debatable.See comparison here:https://sound-au.com/heatsinks.htm#s7But given your last post, I think you're looking for what they put in consumer electric blankets/pads.Fiberglass cloth/fabric maybe?Properties:http://www.lewcospecialtyproducts.com/products/reinforcement-coating-laminating-fabrics/properties-of-fiberglass-fabrics/
Cheap non Chinese PCB manufacturer & assembly for small volume/proto ? - Page 1
Forum section: electronics / projects

author: Miyuki
author_rank: Frequent Contributor
timestamp: July 08, 2021, 06:51:33 pm
content: Hi. Want to ask if you have any experience with any cheap PCB manufacturer other than Chinese ones. Simple 2 and 4 layer jobs for prototyping and tiny batches of 10s or lower 100s. With and without assembly.Do they even exist?

author: mawyatt
author_rank: Super Contributor
timestamp: July 08, 2021, 07:08:14 pm
content: We gave up on this for prototypes and decided to just assemble ourselves. We just did our 1st 100 pin LQFP package (0.5mm pitch) which had me a little worried but came successfulBest,

author: Pineapple Dan
author_rank: Contributor
timestamp: July 08, 2021, 10:46:47 pm
content: I have used aisler and their boards are usually grand and the quality is good. never used their assembly though

author: Miyuki
author_rank: Frequent Contributor
timestamp: July 09, 2021, 12:42:19 pm
content: Quote from: Pineapple Dan on July 08, 2021, 10:46:47 pmTheir pricing looks reasonable and without excessive job tooling costI think I will try themTheir budget price is similar to what I pay for quick prototyping boards without vias (have them delivered the second day )

author: daqq
author_rank: Super Contributor
timestamp: July 09, 2021, 01:21:22 pm
content: Since you're from the Czech Republic, try looking at:https://www.jablopcb.cz/en/https://amset.sk/https://www.printed.cz/osazovani

author: Miyuki
author_rank: Frequent Contributor
timestamp: July 09, 2021, 01:53:41 pm
content: Quote from: daqq on July 09, 2021, 01:21:22 pmPrinted have terrible fixed fees per job.And others don't have public prices. Why the hell they don't have pricesWhat is it a weird custom here?

author: esepecesito
author_rank: Regular Contributor
timestamp: July 09, 2021, 03:05:35 pm
content: Quote from: Miyuki on July 09, 2021, 01:53:41 pmB2B bullshit?

author: poorchava
author_rank: Super Contributor
timestamp: July 10, 2021, 07:07:18 am
content: Yaaa... They do that to get away with giving you 'f*** off' pricing if they don't want to do your order. They can also drain customers who they feel can pay more (eg bigger corporation).Tbh I too bill larger corporate clients more that smaller businesses, but that's because of bureaucracy involved (eg. waiting for 2 weeks for 4 people to approve some minor engineering change)

author: Aiy
author_rank: Regular Contributor
timestamp: July 14, 2021, 04:21:27 pm
content: For work we regularly usehttps://www.eurocircuits.com/Mostly been OK. Had some trouble with no-clean flux residue in keep-out areas (for wire bonding), but in general alright quality.Best regards

author: strawberry
author_rank: Super Contributor
timestamp: July 14, 2021, 05:17:08 pm
content: https://www.volburg.lv/prototyping/http://www.almiko.lv/content/about-usthey do PCB silkscreen ,can print enclosureshttps://www.eevblog.com/wiki/index.php?title=PCB_Assemblers
Cheap OLED displays from a reliable distributor? - Page 1
Forum section: electronics / projects

author: DMoses555
author_rank: Newbie
timestamp: November 24, 2014, 12:12:25 am
content: Hey all, new to this forum so please forgive improper section/formatting. I was just wondering if you guys knew of a place to get decent sized OLED displays (2 inches preferable) in bulk that doesn't involve a one month shipping time from a seedy website. Thanks!

author: tom66
author_rank: Super Contributor
timestamp: November 24, 2014, 12:16:11 am
content: Crystalfontz may be worth considering.https://www.crystalfontz.com
Cheap Power Supplies - Page 1
Forum section: electronics / projects

author: dan3460
author_rank: Frequent Contributor
timestamp: February 02, 2017, 03:24:23 pm
content: Working on a project and coming to a conundrum. I have design a simple power supply with a power transformer to get about 8V a full wave bridge rectifier and a 5V regulator. I'm costing the transformer and the other few pieces at about $10-11 range. Then looking in the web I came across the following:http://static6.arrow.com/aropdfconversion/a1acc95a5af12e5e2811bf89f539bb2a36261c05/rs-15-spec.pdf?authToken=eyJ0eXAiOiJKV1QiLCJhbGciOiJIUzI1NiJ9.eyJTZXNzaW9uSWQiOiIzZWxlZzFnbGhicGF6eW4xbmZlZmgzMWsiLCJEb3dubG9hZFR5cGUiOiJEYXRhc2hlZXRzIiwiaXNzIjoic2VsZiIsImF1ZCI6Imh0dHA6Ly9kYXRhc2hlZXRhdXRoLmFycm93LmNvbSIsImV4cCI6MTQ4NjA0NzQwOSwibmJmIjoxNDg2MDQ3Mjg5fQ.Da_0wQiCmgh55cdgxR7APFOfTw7m2mQFF6_1-Xiqk_cfor about $7, including freight I'm probably are at the same cost as my design.For my project I need 5V at about 500mA so this unit will have plenty. One of the things that I like from this unit is that will free some space on my board.Has anyone have any experiences with this type of power supplies?

author: grifftech
author_rank: Frequent Contributor
timestamp: February 02, 2017, 03:41:11 pm
content: just buy some cheap USB chargers.

author: rstofer
author_rank: Super Contributor
timestamp: February 02, 2017, 04:07:30 pm
content: Or something like this:https://www.amazon.com/ZJchao-2000mA-Regulated-Supply-1-35mm/dp/B005CVNH1Q/ref=pd_lpo_23_lp_t_4

author: dan3460
author_rank: Frequent Contributor
timestamp: February 02, 2017, 04:28:26 pm
content: A little more background on this thing. I'm bringing AC power to the unit and tapping that to power the unit. I don't want it to look cheese, with a wall wart, or a usb tucked inside the box.

author: ThomasDK
author_rank: Regular Contributor
timestamp: February 02, 2017, 07:59:26 pm
content: These are hard to beat on price and size:https://octopart.com/irm-03-5-mean+well-71094830Thomas

author: dan3460
author_rank: Frequent Contributor
timestamp: February 02, 2017, 09:02:02 pm
content: Yes, saw this one but i'm worried that is too closed to the capacity that I need. I'm buying a couple of this to put on the prototype and test. Do you have any experience with this?
Cheap precision voltage divider networks - Page 1
Forum section: electronics / projects

author: SingedFingers
author_rank: Frequent Contributor
timestamp: January 18, 2017, 01:55:03 pm
content: I'm trying to restore an old DMM my father made. It annoyingly has a divider network on it that is damn expensive by the looks, probably one he nicked from work. The lowest value resistors are toast. It appears to be equivalent to a Vishay CNS471A6 which is currently £30which is a higher value than throwing it in the bin which I'd like to avoid.Does anyone know a cheaper solution to this? It appears you can't get exact value 9M, 900k, 90k 9k resistors easily so bodging a divider network is difficult if not more expensive considering minimum quantity of resistors these days...Edit: I've looked at Caddock dividers and they come up the same price.

author: bobaruni
author_rank: Regular Contributor
timestamp: January 18, 2017, 03:25:10 pm
content: Crikey, that is the most expensive resistor I have ever seen, $94.45 from E14....Just roll your own using discretes, use 2 each of the following in parallel to make the correct values:18M, 1.8M, 180K and 18K, the higher values are available at best 1% tolerance but you could hand match them or use smaller R's in series to make use of 0.1% R's

author: SingedFingers
author_rank: Frequent Contributor
timestamp: January 18, 2017, 03:31:36 pm
content: That's a great option. No idea why I didn't see that value relationship! Thanks for the tip!1% is probably fine for this if I'm honest. The timebase for the integrator isn't temperature compensated so I think 0.1% is probably a waste.

author: SingedFingers
author_rank: Frequent Contributor
timestamp: January 18, 2017, 04:28:56 pm
content: Just went through my nice collection of Vishay MRS25 / TE LR1F resistors (all 1% 0.6W 50ppm) and paired up a ton and found all the values apart from the 18M one. I couldn't find any 18M or 9M resistors so I spent some time pairing up a 4M7 and a 4M3 in series which I did have. Assuming my bench DMM isn't terribly calibrated I got it good to 0.5% across all values which is better than I was expecting. Only side effect is there are resistors everywhereProblem appears to be solved. Thanks again!
cheap remote control unit - Page 1
Forum section: electronics / projects

author: WB8PFZ
author_rank: Regular Contributor
timestamp: June 14, 2022, 01:09:32 pm
content: I am looking to purchase a cheap remote control unit to control one circuit. It will be controlling a 3 amp 6 volt motor. Can someone recommend one? It needs to travel 100 feet. Thanks Mike

author: fordem
author_rank: Regular Contributor
timestamp: June 14, 2022, 01:23:46 pm
content: What are you looking for - basic on/off? digital proportional? If it's basic on/off go buy a kiddie rc car that runs on 4AA batteries, strip the guts out and add a relay to handle the 3A motor current.

author: WB8PFZ
author_rank: Regular Contributor
timestamp: June 14, 2022, 01:54:25 pm
content: That's exactly what I have done ( need to get the relay) Looking to see if there is one available for a future project. (running out of rc cars)

author: ledtester
author_rank: Super Contributor
timestamp: June 14, 2022, 03:17:32 pm
content: There are these 433 Mhz modules you can get on ebay/aliexpress that look like this:They come in a variety of configurations. Search for "433 Mhz transmitter receiver".You can also get IR controlled relay modules like this:

author: Benta
author_rank: Super Contributor
timestamp: June 14, 2022, 05:56:03 pm
content: Garage opener remote. It doesn't get cheaper or simpler.

author: WB8PFZ
author_rank: Regular Contributor
timestamp: June 14, 2022, 06:02:52 pm
content: I think the rc car idea is a lot smaller and cheaper. What voltage would I need at the receiver? This is going in the back yard and needs to run off batteries.

author: Benta
author_rank: Super Contributor
timestamp: June 14, 2022, 06:18:09 pm
content: Nominally 4.8 V, but 4.5...6.0 is normally OK.
Cheap, simple and sufficiently accurate frequency standard - Page 1
Forum section: electronics / projects

author: erikka
author_rank: Regular Contributor
timestamp: July 18, 2021, 11:39:25 am
content: Yes, there are many many GPSDO designs and the designs with a stable VCXO, an accurate DAC and long measurement time will always be better than this design.But my goal was to combine some simple modules to have a frequency standard that can be used to check other oscillators.Counting the output of a 10MHz oscillator requires at least 100 seconds to reach 1e-9 accuracy so the phase detector from the Lars GPDSO was addedThis phase detector measures every second in ns seconds accuracy the time between the up edge of the PPS and the first up edge after the PPS from the oscillatorMy version of the phase detector uses a single 7474 (dual set/reset flipflop, see simulation picture)Instead of a VCXO a SI5351 is used with dedicated driver that allows setting the 10MHz output of the SI5351 in 0.001 Hz accuracy.Disadvantage of the SI5351 is the interruption of the output every time the VCO is updated and the jumps in frequency when updating the fractional output divider but for my application (frequency reference) it is sufficient to open the control loop for the (short) duration of the measurementFor best stability it is recommended to replace the Xtal in the SI5351 with a cheap TCXOSW and schematics can be found here:https://github.com/erikkaashoek/Arduino_SI5351_GPSDO

author: erikka
author_rank: Regular Contributor
timestamp: July 18, 2021, 11:43:42 am
content: And here the measurement of the correction (red trace) and frequency set to get the required 10MHz output(blue trace)This is the version with a TCXO on the SI5351

author: Terry Bites
author_rank: Super Contributor
timestamp: July 18, 2021, 02:46:06 pm
content: So you do or do not want a GPSDO as a lab standard?Buy one or get a kit.

author: erikka
author_rank: Regular Contributor
timestamp: July 18, 2021, 03:41:36 pm
content: I must have been very unclear.The github link refers to the GPSDO I'v designed and build based on some ideas I found on the internet.The chart shows its current performance which is sufficient for me (below 1e-8 error) to act as a lab standard as I need at least 10Hz accuracy at 1GHz.The accuracy is reached within 5 minutes after cold start.
Cheap single-chip power management solution - any recommendations? - Page 1
Forum section: electronics / projects

author: george.r
author_rank: Contributor
timestamp: February 13, 2024, 05:52:05 pm
content: Hi all,Having found nothing during a cursory search, I come here to ask: does anybody have an integrated solution that they like that will do LiIon/LiPoly charging from USB, and provide a 3.3V buck output from either USB or battery on a single chip?I am aware of the LTC3557/3559, but unfortunately those run afoul of the rather tight budget for this project (we're talking a few thousand units, so every dollar adds up). That's also why I'd rather not have a separate charger and separate buck (means twice the inductors, more passives, more cost). I don't need crazy high output current, either. Just running a small color display off a microcontroller and some other peripherals, no radios or anything fancier.Thanks!
Cheap, small, optoisolated part to switch 60VAC 100mA - Page 1
Forum section: electronics / projects

author: con-f-use
author_rank: Unknown
timestamp: June 20, 2015, 01:00:44 pm
content: I'm looking for a cheap, small SMD part to switch 100VAC from 3.3V logic. Load is inductive and draws about 100mA continous. Something like an opt-triac. Everything I seem to find is cost >2$. Would welcome suggestions.

author: Jeroen3
author_rank: Super Contributor
timestamp: June 20, 2015, 01:19:39 pm
content: There are- Omron G3VM...- IXYS CPC...- Sharp PR...- Panasonic AQ-HSome are under 1 EURO in the digikey catalog.But there might be a catch with pure inductive loads that I'm not aware of.

author: con-f-use
author_rank: Unknown
timestamp: June 20, 2015, 01:38:34 pm
content: Thank you very much for the suggestions. I don't think there will be another catch besides having to use an RC snubber.Thecpc on aliexpressgo for <0.30€.I could really bite my ass right now, because I know, I saw the perfect IC for this about a year ago. It was mentioned in a project on Hackaday, or some similar site. The IC was intended to switch 120VAC with small currents and cost about 0.20$ a piece. It was in an 8 pin dip package. For the life of my I don't remember the project or the IC's name. Back then I thought about saving it, but didn't because I live in the EU and didn't expect to use something like it on anything other than our 230V. Should've known that a bookmark is cheap.

author: dom0
author_rank: Super Contributor
timestamp: June 20, 2015, 02:56:12 pm
content: Sharp S26M D02?

author: edavid
author_rank: Super Contributor
timestamp: June 20, 2015, 06:50:33 pm
content: How about a good old MOC3010?

author: eneuro
author_rank: Super Contributor
timestamp: June 21, 2015, 11:30:44 am
content: Quote from: con-f-use on June 20, 2015, 01:00:44 pmI'd consider AC mosfets switch which can have small footprint depending on used N channel mosfets and PVI optoisolated gate driver described therehttp://www.irf.com/technical-info/designtp/dt94-5.pdf.However, those photovoltaic isolators provide very small gate current, so forget about fast switching but it might work as AC SSR, at least with resistive load.
Cheap SMB shorting dust-covers or dummy loads? - Page 1
Forum section: electronics / projects

author: Pack34
author_rank: Frequent Contributor
timestamp: February 03, 2017, 06:04:41 pm
content: I'm using a small SMB connector for an interlock and wanted to source some cheap dust-covers or dummy loads for when the interlock is not needed.I'm looking for more of a dust-cap like you see for BNC connectors. Those seem to be easy to find any only cost a couple dollars. Some of the dummy loads I've been able to find for SMB connectors are upwards of $20.Does anyone know of a place to buy these cheaply? I just need to ground the signal.
Cheap source of flexible PCB in china - Page 1
Forum section: electronics / projects

author: ali_asadzadeh
author_rank: Super Contributor
timestamp: June 10, 2019, 08:09:50 am
content: Hi,Hopefully JLCPCB have saved lots of lives!I wonder if there is some similar company doing flexible PCB, do we have such a luxury? I have some cool ideas and they are very cost sensitive! do we have some cheap, reliable and online quotation?

author: E.Buer
author_rank: Contributor
timestamp: June 10, 2019, 09:50:36 am
content: PCBway has instant quote on Flex PCBs. Not sure how they compare to JLC pricewise.

author: fuzzoli
author_rank: Regular Contributor
timestamp: June 10, 2019, 10:02:59 pm
content: I have a similar need and found this company:https://www.goldphoenixpcb.com/fpc-pool.htmlI haven't tried them yet, but the concept looks interesting.

author: KL27x
author_rank: Super Contributor
timestamp: June 11, 2019, 12:20:17 am
content: If you want just 10 boards for prototyping, you might want to check out ITEAD's FPC proto service. You can get 10 small FPC for $100.00.From a regular manufacturer like Gold Phoenix, for instance, you might have to shell out more than double that to get started. They are gonna charge pretty much the same for 1 board or a whole panel. But you know you can order the production board and it will be exactly the same. And for the higher initial cost, you may be receiving many times as many proto boards. This might be useful if you need more than 10 boards to determine failure rates and manufacturing issues.If you buy in high enough volume, the price between a vanilla FPC and rigid can be pretty small. FPC is only crazy expensive in small quantities.QuoteMany chinese factories will give anyone quotes. Just take the time to fill out their quote page and upload a gerber. If you're gonna do thru all that trouble, be sure to request quotes for multiple quantities to see what the price:quantity curve looks like. That's what those fields are for. Use them.BTW, I remember when this was intimidating to me. I talked with some domestic companies. Minimum cost of $1000 for someone to hold your hand through the process. All you really need to know that is different from rigid, as far as buying boards from china, anyway, is a few things. The material is polyimide. It comes in a couple basic thicknesses. 0.1mm or 0.2mm. The soldermask is an additional lamination of polyimide with holes punched in it. You can add additional laminations/stiffeners or adhesive backings for additional charge. Everything else, you can learn from mistakes cheaper than paying someone with experience.

author: ali_asadzadeh
author_rank: Super Contributor
timestamp: June 11, 2019, 12:06:28 pm
content: Guys thanks for the tips!
Cheap SPI MRAM - any experience with PM004MNIATR? - Page 1
Forum section: electronics / projects

author: blinken
author_rank: Newbie
timestamp: May 25, 2024, 07:48:46 pm
content: I'm looking for options for cheap (<$4), SPI-addressable, 1-4Mbit of fast memory for a new project and I came across these SOP-8 MRAM modules from Shanghai Siproin Microelectronics:4Mbit PM004MNIATR, qty 10 USD1.9123https://www.lcsc.com/product-detail/Random-Access-Memory-RAM_Shanghai-Siproin-Microelectronics-PM004MNIATR_C5444277.html2Mbit PM002MNIATR, qty 10 USD1.6604https://www.lcsc.com/product-detail/Random-Access-Memory-RAM_Shanghai-Siproin-Microelectronics-PM004MNIATR_C5444277.htmlDoes anyone have any experience with these parts? The cheapest option @ digikey.com for a 2Mbit SPI MRAM module is USD $6.67 (qty 1000), so this would be a substantial improvement.

author: Benta
author_rank: Super Contributor
timestamp: May 25, 2024, 09:15:41 pm
content: Why does it have to be MRAM?F-RAM or nvSRAM are much more common.https://www.infineon.com/cms/en/product/

author: MT
author_rank: Super Contributor
timestamp: May 25, 2024, 09:33:07 pm
content: 50Mhz max is not fast, even SPI Psuevdo RAM(old school DRAM) does at least 133Mhz

author: blinken
author_rank: Newbie
timestamp: May 26, 2024, 09:48:35 am
content: Quote from: Benta on May 25, 2024, 09:15:41 pmThanks for the suggestion! I'd totally take FRAM (or any other fast-write technology), but the cheapest Infineon part I can find is FM25V20A-PG, USD4.60 @ digikey.Quote from: MT on May 25, 2024, 09:33:07 pmI mostly just need fast writes to an SPI or I2C memory block to buffer some collected data for processing - 50MHz is plenty fast. Something like the Microchip 23LCV1024-I/ST actually looks pretty good though.
Cheap supplier for Wiring harnesses?? - Page 1
Forum section: electronics / projects

author: jmole
author_rank: Regular Contributor
timestamp: April 21, 2013, 08:25:19 pm
content: I'm looking for a company who can make a pretty simple wiring harness in mid-volume quantities (1000 or so).It's basically an 8-pin molex connector with 8x 1.5' wires connected to it, and terminated in spade receptacles, like these:http://www.elecdirect.com/product/fd156437-db1c-4833-b81b-d2dfc5e1c6d7.aspxI've been searching google, but all I find are these people making super complex wiring harnesses for aerospace applications that cost $100's for each unit.Anyone have any suggestions?

author: daedalus
author_rank: Regular Contributor
timestamp: April 22, 2013, 12:18:37 am
content: Why not just buy the tooling, then find someone willing to crimp wires for you, either someone working from home, or a local pcb assembler, etc. At this quantity its probably the cheapest way to go.

author: lgbeno
author_rank: Frequent Contributor
timestamp: April 22, 2013, 02:14:51 am
content: What would you want to spend?Can't some of the Chinese Porto places arrange something like this. Maybe elecrow?Otherwise try sinbon

author: nanofrog
author_rank: Super Contributor
timestamp: April 22, 2013, 02:53:20 am
content: Get a bid from this place, and see if it's what you're looking for (specialize in small - medium orders, and the work is done in the US, so should be able to meet shorter lead times):http://ramoem.com/
Cheap toaster reflow oven did 130 PCB's great - Page 1
Forum section: electronics / projects

author: exoticelectron
author_rank: Regular Contributor
timestamp: April 10, 2017, 06:58:18 pm
content: Heres my super cheap reflow setup, which I used to solder about 130 circuit boards, 5 at a time, for my dual thermocouple gauge. I gutted the toaster ovens thermostat/switch and replaced it with an off the shelf PID temperature controller. Since my PCB's had SMT on both sides, I had to protect one side from the heat, so I used a small section of refractory blanket to lay the already-soldered side on to which blocked the heat, along with some aluminum foil reflectors under it. Worked great and never had any parts fall off the protected side.The thermocouple for the PID controller was passed through the wall of the oven to the interior to measure the inside temperature. Its a flexible wire type so you can bend it so the junction goes right above the circuit boards for accuracy.This setup was very cheap and worked well. I would say unless you want a reflow oven project as a project in itself, that you can make something simple like this for very cheap and get on with soldering your circuit boards.Using it is very easy. In fact you might be able to get away without the PID controller as long as you have a fast response thermocouple located right above the circuit boards, heres why:To startup, load the boards, then plug in the oven. To get the ramp rate as fast as possible I just manually override the PID to 100% duty cycle until things get up near 390F. Then I engage the PID and the temperature usually gets to 420F and is under control there for about 30 seconds if I remember right. Keep an eye on the parts with a flashlight to see when they reflow. Once they are shiny, unplug the oven and pull them out to cool. Voila! The PID controller didnt really do anything except maintain the temperature around the peak for a few seconds, which it would probably have done anyway just from thermal inertia. So I think you could probably get rid of it.Project cost:-used toaster oven $10 (thrift store, garage sale)-PID controller $15 (ebay)-thermocouple $5 (ebay)-refractory blanket $5 (ebay)-solid state relay $10$45USD