hybridfree/eevblog-posts huggingface dataset:
Cheap DC Volt/Amp meter that measures on positive leg - Page 1
Forum section: electronics / beginners

author: PhysicsDude55
author_rank: Contributor
timestamp: June 24, 2020, 03:41:31 pm
content: I have a few projects coming up where I want some of those cheap small panel mount Volt/Amp meters like these:I have about a dozen different ones that I've ordered from China. The problem is that they all measure current on the "negative" side, like this:For some of my projects I want these for, there will be a common negative to many devices (automotive stuff, PC bench power supply, etc). Does anyone know of a relatively cheap volt/amp meter that's roughly the same form factor that can measure current on the "positive leg" of the circuit? I understand why they design them to measure off the negative, and why that's a simpler/cheaper design, but wanted to see if anyone knew of some different models that measure differently.Thanks!

author: bob91343
author_rank: Super Contributor
timestamp: June 24, 2020, 08:39:10 pm
content: You probably need two units instead of one.

author: Ian.M
author_rank: Super Contributor
timestamp: June 24, 2020, 08:58:01 pm
content: To do high side current sensing, one needs either an isolated sensor like Allegro's range of ACS... Hall effect current sensing ICs, or an 'over the top' OPAMP + precision matched resistors to implement a differential amplifier, with sufficient gain to keep the shunt burden voltage low enough, but also with excellent common mode rejection. Either option significantly increases component costs, so no cheap meters. Low side sensing doesn't have the same problems as there's no common mode voltage to reject, so no need for precision matched resistors, and any 'jellybean' OPAMP with a common mode range including its negative supply is suitable to amplify the shunt voltage to a suitable range for the ADC.

author: ledtester
author_rank: Super Contributor
timestamp: June 25, 2020, 04:51:24 am
content: You might see if this (5-year old) video is applicable to your displays:It is quite likely that the design mentioned in the video is not available anymore.

author: Ian.M
author_rank: Super Contributor
timestamp: June 25, 2020, 08:39:41 am
content: Unfortunately,without a datasheet for the differential ADC + PGA IC, there's no way of telling whether or not its inputs have an 'over the top' common mode range. If it doesn't odds are taking them outside the rails (which is only 0V to 3.3V if it shares Vcc with a 3.3V MCU) will let the magic smoke out. Also current measurement accuracy may be compromised before it reaches 3.3V common mode.One approach that would work even if the modules no longer use that circuit, would be to remove the shunt, and build an over the top capable unit gain differential amplifier to allow the shunt to be inserted in an arbitrary positive rail, and translate the differential voltage across it down to an equal zero referenced voltage that can be injected at the load terminal of where the shunt was. Its differential rejection could be hand trimmed, with lets say a 1mA test current through the shunt, while varying the rail voltage, so it could be built with only 0.1% resistors.
Cheap DC Volt/Amp meter that measures on positive leg - Page 1
Forum section: electronics / beginners

author: PhysicsDude55
author_rank: Contributor
timestamp: June 24, 2020, 03:33:04 pm
content: I have a few projects coming up where I want some of those cheap small panel mount DC Volt/Amp meters like these:I have about a dozen different ones that I've ordered from China. The problem is that they all measure current on the "negative" side, like this:For some of my projects I want these for, there will be a common negative to many devices (automotive stuff, PC bench power supply, etc). Does anyone know of a relatively cheap panel mount DC volt/amp meter that's roughly the same form factor that can measure current on the "positive leg" of the circuit? I understand why they design them to measure off the negative, and why that's a simpler/cheaper design, but wanted to see if anyone knew of some different models that measure differently.Thanks!

author: Vovk_Z
author_rank: Super Contributor
timestamp: June 25, 2020, 07:58:38 am
content: I have seen the same LED panel meters but with isolation DC/DC inside, sometimes it may help a little. But it can't help measure both current and voltage on the high side. I haven't seen ready-made volt-amper-meter for high side measure of current, unfortunately.

author: Ian.M
author_rank: Super Contributor
timestamp: June 25, 2020, 08:12:40 am
content: O.P.'s multiposted the same questionhttps://www.eevblog.com/forum/beginners/cheap-dc-voltamp-meter-that-measures-on-positive-leg-244945/
Cheap differential probe with a AD8421? - Page 1
Forum section: electronics / beginners

author: eTobey
author_rank: Super Contributor
timestamp: January 04, 2025, 06:47:32 am
content: I readhere, that a AD8421 can be used to build a differential probe. And with that, i found the following products:https://de.aliexpress.com/item/1005005747516705.htmlhttps://www.ebay.de/itm/355082474820Can these products be used as a differential probe? If not, could they be modified in a simple way to accomplish that?Signals would be up to 42V and i would be satisfied with a risetime of tens of nanoseconds.

author: Kleinstein
author_rank: Super Contributor
timestamp: January 04, 2025, 07:21:08 am
content: The modules seem to have no extra protection. So they are likely easy to damage. The input is also DC coupled only and the voltages need to be in a rather limited range set by the supply and CM range of the chip.This makes them useful for special cases with small signals / low voltages (e.g. 1 V), if used with care. It than has low noise (less than most scopes).The usual differential probes start with a high impedance divider and a differential amplifier to get a much larger voltage range. The shown amplifier is not ideal for the relatively high impedance (e.g. 100 K) of such a divider.Speed wise the linked amplifiers are more in the 100-300 ns range for the rise time.
Cheap dirty driving of a miniature speaker with logic gate - bad or good enough? - Page 1
Forum section: electronics / beginners

author: daqq
author_rank: Super Contributor
timestamp: July 11, 2014, 02:08:54 pm
content: Hi guys,For a project that would benefit off a beeper indicator, I would like to use the ABMT-801-RC micro speaker ( datasheet:http://datasheet.octopart.com/ABMT-801-RC-Pro-Signal-datasheet-8816666.pdf). I would like to drive it from 3.3V from a single gate 74HC1G00 device, through a 10 uF coupling cap. The gate should act as an amplifier/driver so it would not be driven directly by the MCU GPIO. The MCU will provide a 1-4 kHz signal to drive it.The speaker has a resistance of around 10 Ohms. My questions are: Is such a gate suitable for this kind of use? Will it be reliable? If not, what's the cheapest way of driving such a micro speaker?Thanks,David

author: Simon
author_rank: Unknown
timestamp: July 11, 2014, 04:21:48 pm
content: how about just driving it off a small mosfet ?
Cheap DMM - Uni-T UT890D - Page 1
Forum section: electronics / beginners

author: LEDAero
author_rank: Regular Contributor
timestamp: March 31, 2015, 12:55:03 am
content: I just bought my Dad a new multimeter to replace his old broken down one.He says it's great and much better than the one he broke. (he also has a 30 year old Fluke, but says he is too old to get it fixed... he only needs one to last 5 years) He is an EE of significant vintage - but completely analogue until only a couple of years ago.It is a Uni-T 890D - 6000-count, True RMS and the best part - $13.99.I recently bought a Uni-T UT61E and am very pleased with it, but it cost 4x what this one does. I am going to order one as my 'garage' meter.http://www.aliexpress.com/item/2015-New-arrival-UNI-T-Digital-Multimeter-manual-range-true-RMS-tRMS-REL-AC-DC-frequency/32283150142.htmlIt was packed well, shipped fast and arrived in NZ in about ten days. It did have a Chinese manual with it, but the vendor is sending me the link to the English manual. I will post the link here.It has CE / CAT.II 1000V / CAT.III 600V certification (if you believe that stuff)It looks like a good beginners meter on a budget.

author: retiredcaps
author_rank: Super Contributor
timestamp: March 31, 2015, 01:29:13 am
content: Quote from: LEDAero on March 31, 2015, 12:55:03 amIf you want to try and fix his old Fluke, start a new thread and I will try to help. You will need to post the model number and state what is wrong with it.

author: LEDAero
author_rank: Regular Contributor
timestamp: April 01, 2015, 07:58:03 am
content: Quote from: retiredcaps on March 31, 2015, 01:29:13 amHe's about 7500km from me, but I will get the info from him. Thanks
Cheap electronics enclosure for low quantity - Page 1
Forum section: electronics / beginners

author: VEGETA
author_rank: Super Contributor
timestamp: February 12, 2020, 09:01:51 am
content: Hello,I've been wondering about how does people with low quantity (<=100) manage to get enclosures for cheap. Enclosures like 150x100x70mm or anything similar. Prices on Aliexpress are good for up to 5 quantity which is nice for DIY stuff but not if you have a project that you want to sell right?Not to mention shipping costs which are huge due to size and weight which you cannot go around it IMO. All of this by assuming you have PCB front and back panelsto further reduce costs of milling and printing (are they too costly?).So a quick calculation about one of those aluminum enclosures from Aliexpress turned out to be 25$ per unit including shipping! this is kinda a lot right? so if I have say 40$ worth of component costs + 25$ = 65$ =~ 70$ in total per unit cost. x2.5 as Dave says = 175$ selling price which is a lot TBH. BTW the project I aim to design properly and sell is a lab psu with batteries (sepic pre-regulator 1v difference, 30v-3a, batteries charging and protection...etc)So I wonder what is your experience with this issue.thanks!

author: beanflying
author_rank: Super Contributor
timestamp: February 12, 2020, 09:36:12 am
content: Have a read of this recent thread for links and results.https://www.eevblog.com/forum/manufacture/custom-aluminium-anodized-cncd-enclosure/msg2759686/#msg2759686

author: EEEnthusiast
author_rank: Frequent Contributor
timestamp: February 12, 2020, 09:57:50 am
content: I buy my boxes from SZOMK. They are reasonably priced and they will cut the holes needed on the front and back panels. Also laser etching for the text instead of screen printing. The aluminium enclosures from them are of good quality. you could contact them on their website. They do have an MOQ for the cutting, but 100 Qty should be Ok.https://www.chinaenclosure.com/

author: VEGETA
author_rank: Super Contributor
timestamp: February 12, 2020, 12:31:46 pm
content: Quote from: beanflying on February 12, 2020, 09:36:12 amThanks for directing me there. Nice thread.QuoteI know them, they seem popular. What is your product? I'd like to see the final result and how to stack your PCB to the front panel.
Cheap Func. Gen. to Exercise an Old CRT O'scope - Page 1
Forum section: electronics / beginners

author: jdutky
author_rank: Regular Contributor
timestamp: December 08, 2020, 02:06:30 am
content: I'm thinking of getting one of these inexpensive RF signal generators from eBay (https://www.ebay.com/itm/ADF4351-35M-4-4G-RF-Signal-Generator-PLL-Sweep-Frequency-Generator-Touch-Screen/283893337277) as a way of generating high frequency signals that can test the limits of my old Tektronix 475 and 475A oscilloscopes. The price is certainly right, but I'm not actually sure what these RF function generators do. Does anyone have experience with these?I'd really like to have something that could produce a modulated sine wave (like Dave uses to demo scopes in the EEVBlog videos) but I'd be perfectly happy with just being able to generate sine waves in the 100-500 MHz range and see the rolloff on my scope at higher frequencies.-- Jeff Dutky

author: bob91343
author_rank: Super Contributor
timestamp: December 08, 2020, 03:29:46 am
content: In my experience the cheapest way to get a generator like this is from a private party. For instance I have a boat anchor generator that goes to 400 MHz, calibrated and leveled, with AM built in, that I don't use. Surely there is someone local to you that has something similar to give or lend or sell to you. PM me if you are near Los Angeles.I don't think there is a better answer. Of course the heavy tube units are electrical bargains but you need to consider the space they take.Insidentally I recall seeing a rising output voltage with frequency until I realized the test cable wasn't terminated.
Inexpensive GPS modules supporting raw measurement? - Page 1
Forum section: electronics / beginners

author: abhishekkumar1902
author_rank: Regular Contributor
timestamp: December 13, 2017, 12:41:22 pm
content: I am working on an application where I want to implement RTK (Real Time Kinematics) and/or DGPS (Differential GPS) which needs GPS modules which supports raw measurements for example the NEO-7P module from ublox. NEO-7P is a pretty expensive module costing around 70$. I just wanted to know if there are any inexpensive GPS modules available in the market which supports raw measurement?

author: David Hess
author_rank: Super Contributor
timestamp: December 13, 2017, 06:52:28 pm
content: I did not know that any of the Ublox GPS receivers or anybody elses supported raw measurements. Huh, it even says it supports raw data in the specifications.Raw measurement output is supported for GPS signals at an update rate of up to 10 Hz. The UBX-RXM-RAW message includes carrier phase with half-cycle ambiguity resolved, code phase and Doppler measurements, that can be used in external applications that offer precision positioning, real-time kinematics (RTK) and attitude sensing. The UBX-RXM-SFRB message contains sub-frame data for GPS and SBAS satellites.$70 seems like a deal for that.

author: Gyro
author_rank: Super Contributor
timestamp: December 13, 2017, 08:22:22 pm
content: The LEA-6T also supports Raw data output (5Hz on the LEA-6T-0 and 2Hz on the LEA-6T-1).I think I remember reports of some sort of bug in it though or workaround needed, possibly resulting in it appearing in a bunch of cheap ebay GPS (+ Compass) units for drones.e.g.https://www.ebay.co.uk/sch/i.html?_from=R40&_trksid=p2380057.m570.l1313.TR0.TRC0.H0.Xlea-6T.TRS0&_nkw=lea-6T&_sacat=0Probably worth some further research on the subject.

author: edavid
author_rank: Super Contributor
timestamp: December 13, 2017, 08:48:48 pm
content: There is also a $50 NavSpark module:http://navspark.mybigcommerce.com/ns-hp-rtk-capable-gps-gnss-receiver/
Cheap intl. online sources for good caps? - Page 1
Forum section: electronics / beginners

author: lpc32
author_rank: Frequent Contributor
timestamp: March 24, 2014, 10:31:46 am
content: Are there are known trustworthy online stores for good caps, with good prices and cheap international shipping?Tayda, Futurelec, and similar stores, either don't have much of a cap selection or just carry generic/unknown ones.There are some on eBay, from sellers with >99% rating, but I don't know if those caps are authentic (e.g.,Rubycon MCZ, orPanasonic FJ).

author: mariush
author_rank: Super Contributor
timestamp: March 24, 2014, 03:15:55 pm
content: Digikey.com .ca (if you buy a lot, you get free shipping) - they may have UK shipping at some point if not already, not sureMouser.com - US but cheap shipping if you buy a lotFarnell.com (newark.com in US, element14.com in some other places)RS-Online.comdistrelec.comand there's others but I can't remember them right now.Tip: find a part you're interested in, get the part code and search for it in findchips.com and then see those companies' shipping policies.

author: lpc32
author_rank: Frequent Contributor
timestamp: March 24, 2014, 03:47:40 pm
content: Okay, I should've added: very small quantities.

author: AKM
author_rank: Contributor
timestamp: March 24, 2014, 04:20:12 pm
content: Never had problem with this guy on ebay:http://www.ebay.com/usr/egekecu

author: lpc32
author_rank: Frequent Contributor
timestamp: March 24, 2014, 04:40:50 pm
content: That seller does indeed have a good rating.But I wonder how can one tell if the caps are authentic.

author: mariush
author_rank: Super Contributor
timestamp: March 24, 2014, 04:59:33 pm
content: Well, if you want just a few capacitors and you're in Europe or close to Europe, pm me.I buy stuff from Farnell regularly aso i can cover the shipping costs from farnell to me. I can mail you small capacitors for farnell's price (or even lower if i happen to have bought already what you want in quantity), plus 2-3$ shipping (stamps and bubblewrap envelopes)

author: BravoV
author_rank: Super Contributor
timestamp: March 24, 2014, 06:26:35 pm
content: Quote from: AKM on March 24, 2014, 04:20:12 pmJust fyi, bought bunch of high performance Sanyo OSCON solid caps from this seller, and they're all genuine and perform as specification.

author: lpc32
author_rank: Frequent Contributor
timestamp: March 25, 2014, 02:26:48 pm
content: Thanks mariush! See PM.BravoV, how did you verify their authenticity? That various signs point to a trustworthy seller, but those "short leaded" caps he sells do suggest something odd, at least for these specific caps.
Cheap-ish multimeter with insulation resistance tester? - Page 1
Forum section: electronics / beginners

author: fubar.gr
author_rank: Unknown
timestamp: August 09, 2016, 07:44:37 am
content: I am routinely dealing with electric motors or other electrical installations that have some earth leakage and trip the RCD. In such cases, an insulation resistance tester is an invaluable tool.I have a UNI T UT513, but it is quite a beast to haul around. So it would be nice to have a multimeter with an integrated insulation resistance tester.But all such meters are made by Fluke, Gossen Metrawatt, Keysight, etc. Is there any cheaper meter available?I am not interested in particularly high voltages, or measuring Polarization Index and such. A single resistance measurement as a pass/fail test is enough for my needs.

author: TheAmmoniacal
author_rank: Unknown
timestamp: August 09, 2016, 08:02:25 am
content: The cheapest option I could find was the UNI-T UT533 ~ €110 (or alternatively the UT505A)A good quality "medium" option is the Brymen 878 ~ €260
Cheap Kapton Tape Adhesive Question - Page 1
Forum section: electronics / beginners

author: t1d
author_rank: Super Contributor
timestamp: November 10, 2018, 07:57:43 am
content: I have some... Never again... Its adhesive fails, at temperature. Does the adhesive hold, at temperature, for the real stuff?

author: xavier60
author_rank: Super Contributor
timestamp: November 10, 2018, 09:22:23 am
content: There is supposed to be types that have strong adhesive. I have not been able to track it down.

author: t1d
author_rank: Super Contributor
timestamp: November 10, 2018, 11:25:55 am
content: I think the good stuff is made by 3M. I will add that, to my Mouser.com wish list, for my next order. I guess I can use the cheap stuff to tape up boxes, or some such;-)

author: ArthurDent
author_rank: Super Contributor
timestamp: November 10, 2018, 02:42:28 pm
content: Years ago I worked at a remote weather station in winter that was only accessible by a big snow cat and the temperature never got above freezing for months. There were a lot of experiments that were set up outside where tape had to be used and one of the researchers told me of his theory that the worse the tape adhesive smelled, the better it held. His theory seemed to 'hold' at low temperatures and it might be true for high temperatures as well.
Cheap load for mAh measurement? - Page 1
Forum section: electronics / beginners

author: kalel
author_rank: Frequent Contributor
timestamp: August 23, 2017, 04:28:01 pm
content: I would like to get one of these to get some approximate values. Seems to be capable of measuring V/A like the USB power meters too, could be useful.The unit is not expensive, but the load could be. They seem to give some 7.5 ohm resistors. Product rating comments mention that they can get very hot, but this surely depends on the power going through.E.g. at the low end: 1.5V / 7.5Ohm = 0.2A * 1.5V = 0.3WWhen testing batteries, the voltage will drop eventually. That means the current drawn by the resistor will decrease. Resistor temperature will also affect resistance and current slightly. Do I need a constant current load to measure the Ah value of a battery with this unit, and if so, is there a cheap (being the most important part) way to obtain or improvise one? Slow discharge is fine if needs be. It does not need to be adjustable.

author: jeroen79
author_rank: Frequent Contributor
timestamp: August 23, 2017, 07:37:14 pm
content: Ebay/aliexpress/etc offer a 10A adjustable constant current load for €15-ish.Or you can put something together with a transistor.Feed the transistor's base through a resistor from the 5V supply of the discharge tester.How crucial will the current be anyway?Fluctuations in current wouldn't matter, the thing constantly calculates how much charge went through.And it displays the current so you can make adjustments

author: kalel
author_rank: Frequent Contributor
timestamp: August 23, 2017, 08:04:37 pm
content: Quote from: jeroen79 on August 23, 2017, 07:37:14 pmThat's a nice idea. Relatively cheap (for low currents) and adjustable too (although probably more stable to use a resistor than a potentiometer).Quote from: jeroen79 on August 23, 2017, 07:37:14 pmYes, you're probably right there and it makes things easier to just use a resistor if that's good enough for a rough estimate of the capacity. I'm guessing it would matter if the current changes so rapidly that the unit isn't fast enough to measure and factor in the changes. It probably won't change rapidly at all with a battery, so that should be fine.

author: anishkgt
author_rank: Frequent Contributor
timestamp: August 23, 2017, 09:00:44 pm
content: Or you could try this alsoeBay auction: #http://www.ebay.com/itm/18650-li-ion-lithium-Battery-Mobile-Power-Capacity-Tester-Meter-discharge-load-/292125965820?hash=item4404107dfc:g:IrYAAOSw4shYBclkor maybe wait for Lexcelon's battery analyzer
Cheap multimeter : Uni-t 133a vs Aneng An870 vs Aneng An8009 - Page 1
Forum section: electronics / beginners

author: Newbie12
author_rank: Newbie
timestamp: October 24, 2024, 07:41:57 pm
content: Hello guys, I'm looking for a budget relatively fast multimeter for continuity, capacitors, short circuit measurements.Do you know which one in this list, Uni-t 133a, Aneng An870, Aneng A 8009 is faster, especially for continuity/resistor testing ?

author: BeBuLamar
author_rank: Super Contributor
timestamp: October 24, 2024, 10:24:44 pm
content: I wonder why fast coninuity is so hot? About the only time I use the coninuity function is to trace wire for example 2 connectors with a cable in between. I never use the function to check for short.

author: EEVblog
author_rank: Unknown
timestamp: October 25, 2024, 12:02:09 am
content: Quote from: BeBuLamar on October 24, 2024, 10:24:44 pmVery common for finding solder shorts after board assembly for example. A fast continuity buzzer lets you "sweep" quickly across a wide range of contacts.Quickly finding a ground point to connect to is another example.

author: floobydust
author_rank: Super Contributor
timestamp: October 25, 2024, 03:15:36 am
content: As far as I know, there is no standard way to measure continuity response time and so it's all subjective.I'll use an analog circuit design for fast continuity, and have a few DMMS with analog continuity beep that are very fast.-If I need to hear a bad connection crackle in order to find it.-If I am following a PC board trace and need to probe say 50 IC pins fast, to see where it connects.

author: Aldo22
author_rank: Super Contributor
timestamp: October 25, 2024, 06:34:20 am
content: The best cheap DMM for continuity testing that I have is the UNI-T UT123. But it can't do much else.Areviewsays:Continuity is fast in speed (About 15ms).Continuity beeps when resistance is below 30ohmContinuity green led turns on with beep, red led turns on when resistance is below 420ohmContinuity is 2.1V open and 0.26mA shortedIn my opinion, the best cheap general purpose DMM is theZOYI ZT-225It is slightly better than the AN870 in many aspects, but also somewhat larger.Continuity testing is acceptable.

author: Newbie12
author_rank: Newbie
timestamp: October 25, 2024, 10:32:57 am
content: I ordered the Uni-T 89X before seeing your reply , having manual range should be faster. Also it brags that it charges capacitors faster than many others, and has temperature probe. Paid about 25$, we will see, if I like it I will keep it, if not I will return.Another main point is that I found it in my country, so I can return it easily. If I took one from Ali, I would be stuck with it.
cheap online shopping for hardware and components in Australia - Page 1
Forum section: electronics / beginners

author: wilmer
author_rank: Contributor
timestamp: July 30, 2016, 01:56:45 pm
content: Hi, I just start my Ph.D. in Australia, I am at the Australia maritime college in Tasmania.The problem is, there are not many options to buy tools as breadboards, multimeters, or components because it is a small town.can you suggest me places online with cheap shipping on tools for electronics?
Cheap power bench supply, any recommendations? - Page 1
Forum section: electronics / beginners

author: Azhar
author_rank: Regular Contributor
timestamp: August 30, 2020, 04:03:19 am
content: I would like to buy one these cheap chinese bench power supplies, there are lot of models on ebay.thought of asking you see if you can recommend any brand/model!thanks

author: ledtester
author_rank: Super Contributor
timestamp: August 30, 2020, 04:13:50 am
content: For a switching supply, 0-32V 0-5A the Gophert NPS-1601:https://youtu.be/bSkeV2ezuBs

author: ataradov
author_rank: Super Contributor
timestamp: August 30, 2020, 05:20:02 am
content: I would not cheap out. The most generic 30 V, 5 A power supply from eBay/Ali is about $50.KORAD KA3005D is $100, but a way better power supply in all possible respects. I would strongly suggest just getting it and not worrying about what you get from the cheap ones.KORAD is also linear, so no noise issues and much better reaction to variable loads. Having presets and digital controls makes it much harder to accidentally change the voltage/current.

author: JustMeHere
author_rank: Frequent Contributor
timestamp: August 30, 2020, 06:07:17 am
content: I like my TP3005P. The price is a bit up right now.

author: Electro Fan
author_rank: Super Contributor
timestamp: August 30, 2020, 06:42:45 am
content: Quote from: ataradov on August 30, 2020, 05:20:02 am+1Korad KA3005D

author: ercapoccia
author_rank: Regular Contributor
timestamp: August 30, 2020, 07:38:54 am
content: If you not need a linear programmable power supply, Gophert NPS-1601 is excellent for the price.

author: radiolistener
author_rank: Super Contributor
timestamp: August 30, 2020, 10:50:26 am
content: Quote from: ataradov on August 30, 2020, 05:20:02 am+1KORAD KA3005D very good linear power supply with precise output.This is linear power supply and have no switching noises like Chinese switching power supplies.

author: wizard69
author_rank: Super Contributor
timestamp: August 30, 2020, 09:13:06 pm
content: It might help to tell us what you will do with it.The cheap Chinese power supplies can be pretty dismal if you are not careful. As such I wouldn't suggest any model that isn't from an established company with a track record. Further you effectively throw away your money on such products because when the do fail warranty repair is a joke. Even repairing them yourself can be problematic due to low quality and hard to find parts. I just don't see an advantage here in most cases. A decent power supply should last years.More importantly to me is that people end up buying supplies that they really don't need and at the same time pass up the opportunity to build a supply themselves.You may ask why is it important to build a power supply. Fairly simple as supplies are a common failure point in electronics and understanding them is important when it comes to digital stuff. Or to state it another way it is a valuable asset to understand how power supplies work and fail, when working on digital circuits and designs.Quote from: Azhar on August 30, 2020, 04:03:19 am
Cheap ESD Flooring - Page 1
Forum section: electronics / beginners

author: ocset
author_rank: Super Contributor
timestamp: June 12, 2018, 06:06:52 pm
content: Hello,We need ESD flooring for our electronics assembly lab.We will use these ESD floor tiles, they have a resistance of 100 billion ohms per metre^2...https://www.antistaticesd.co.uk/shop/anti-static-esd-mats/heavy-duty-esd-7mm-interlocking-tiles/...so we will put loads of strips of conductive tape beneath them and earth those.Please could you help review this?..it is as in the attached document

author: JourneymanWizard
author_rank: Newbie
timestamp: June 12, 2018, 08:26:39 pm
content: This may help answer your questions:https://www.staticworx.com/articles/the_basics_of_esd_floors.phpHow is it being used (heel clips and conductive shoes? civvies?), and can it effectively be grounded from the back?What is your sensitivity? Can you handle higher risk (e.g. 1kV risk), or are you dealing with sensitive (a few hundred volts) or very sensitive parts (a few tens of volts - probably not, unless you are wire-bonding)?There are some resources at Desco, the ESD Association, and others, including the ESDA article reproduced in a magazine linked belowhttp://sites.csn.edu/slots/ET138B/appendix_b_electrostatic_discharge.htm
cheap smt breakout boards - Page 1
Forum section: electronics / beginners

author: desolatordan
author_rank: Regular Contributor
timestamp: January 06, 2010, 07:36:48 pm
content: I need to stock up on SMT to DIP breakout boards, cheaply. It's hard to find breakout boards for MSOP,SOT23,SC-70 and other small footprints for less than $1 per adapter. Does anyone know of a good source, or a good pcb manufacturer that would let me crank out perforated or v-scored sheets of breakout boards on the cheap side (<$1/adapter).So far, this is the only good deal I've found for SOIC and SSOP.http://www.dipmicro.com/store/PCB-SOIC-SSOP16

author: madworm
author_rank: Frequent Contributor
timestamp: January 10, 2010, 07:19:10 pm
content: Some time ago I had the very same problem, so I chose to have the adapters made.If you have time and can wait for several weeks, I can recommend MakePCB.comI got about 200 MSOP10/TSSOP8 to dip adapters for about 80$ including shipping. They also did the panelizing for me and the boards were v-scored. Quality is good. Double sided silk screen and gold plating and everything ;-)(click for larger image)

author: Unknown
author_rank: Unknown
timestamp: February 05, 2010, 12:22:38 am
content: Futurlec has a variety of SMD breakouts for decent prices. Shipping is slow, however.http://www.futurlec.com/SMD_Adapters.shtml

author: Ferroto
author_rank: Frequent Contributor
timestamp: February 15, 2010, 09:19:28 pm
content: Can I have the gerber files

author: madworm
author_rank: Frequent Contributor
timestamp: April 14, 2010, 08:41:44 pm
content: Of course. Seems like I didn't get a notification of your post.

author: DavidDLC
author_rank: Frequent Contributor
timestamp: April 15, 2010, 07:52:54 am
content: Check Sparkfun, they have some breakboards.http://www.sparkfun.com/commerce/categories.php?c=20I hope this helps you out.

author: johnboxall
author_rank: Unknown
timestamp: April 18, 2010, 09:03:21 am
content: littlebirdelectronics.com has the sparkfun range of SMD breakout boards, but local.

author: tlschumacher2000
author_rank: Newbie
timestamp: January 23, 2012, 05:02:23 pm
content: MadwormDo you still have some of the MSOP-10 -> Dip adapter board?If so, please contact me offline at tlschumacher2000@yahoo.comI am interested in a few (3-4) of them.Thanks for any info.Terry

author: ivan747
author_rank: Super Contributor
timestamp: January 23, 2012, 10:11:14 pm
content: What about making a PCB panel full of assorted SMD footprints to DIP footprints. You would just have to send the gerbers to a PCB fab and you're good to go. THAT's open source hardware put into good use.

author: madworm
author_rank: Frequent Contributor
timestamp: March 15, 2012, 09:21:26 pm
content: Quote from: tlschumacher2000 on January 23, 2012, 05:02:23 pmSorry, no. All gone.Seems I don't get any new-posts notifications...
'Cheap' soldering iron: TS100 or CircuitSpecialists 60 Watt? - Page 1
Forum section: electronics / beginners

author: brych34
author_rank: Contributor
timestamp: November 24, 2019, 09:18:53 pm
content: Hi all,Up to this point I've been using a soldering iron that just plugs into a wall socket. It takes ages to heat up and struggles to melt solder when there is a large mass attached to it.I'd like to upgrade to a soldering station, but I was wondering which one? My budget is only around £50, or $64.I've been looking at these irons:TS100 -https://www.aliexpress.com/item/32860309312.htmlCircuitSpecialists 60 Watt -https://www.circuitspecialists.com/60_Watt_Soldering_Station.htmlDoes anyone have any experience with either? Or do you recommend something else?Thanks.

author: thinkfat
author_rank: Unknown
timestamp: November 24, 2019, 09:48:24 pm
content: TS100, the other one doesn't have a directly heated cartridge. The drawback of the TS100 is, it's a bit flimsy. If you have more than one thumb on each hand, might be a problem.I have a TS100. It's not my main soldering station. But as an on the road tool it's fine.

author: brych34
author_rank: Contributor
timestamp: November 25, 2019, 06:32:53 pm
content: Ok - TS100 it is!Thanks!

author: Domagoj T
author_rank: Frequent Contributor
timestamp: November 25, 2019, 07:23:18 pm
content: I too have TS100 as a secondary iron, and it's pretty decent. What I like most about it is that I can hook it to a small motorcycle battery and have a decent portable iron that just happens to be floating.It is still a bit of a struggle if you try to solder something big. There is a quite significant difference between TS100 and Weller WSP 81 which is my go to iron.

author: Gyro
author_rank: Super Contributor
timestamp: November 25, 2019, 08:01:17 pm
content: These days, portable drill batteries and chargers make a convenient portable power source. In the UK, Lidl are the cheapest.https://www.eevblog.com/forum/reviews/teardown-lidl-20v-2ah-lithium-battery-pack-and-charger/msg2469087/#msg2469087If you use the Ralim TS100 firmware, it has Lithium battery level monitoring and low voltage shutoff included.

author: IDEngineer
author_rank: Super Contributor
timestamp: November 27, 2019, 12:13:28 am
content: Quote from: Gyro on November 25, 2019, 08:01:17 pmI don't know that specific firmware for the TS100, but I definitely second the firmware upgrade recommendation. The stock firmware limits you to 350C, whereas the firmware we loaded onto ours goes to 400C which really helps with higher-mass soldering jobs like connectors. It also permitted a custom startup graphic, so I created one with my son's name so when he loans it to people there's no question to whom it belongs!

author: Gyro
author_rank: Super Contributor
timestamp: November 27, 2019, 09:27:57 am
content: That's probably the one. I forgot to link...https://github.com/Ralim/ts100
Cheap solution for RGB DAC - Page 1
Forum section: electronics / beginners

author: Jaunedeau
author_rank: Regular Contributor
timestamp: May 18, 2023, 06:11:16 am
content: Hi,I'm trying to ouput a video signal from a microcontroler. If I manage to output an 8 color signal (one bit per component), I'll then try adding an ADC that needs to be cheap, with a precision around 1/256, and that can output a signal at in the 3-4MHz range. (I need a 0.7V output in the end)I don't know much about analog components and am a bit lost on mouser trying to find the solution. Is there some ready made, easy to find abvious solution ? Should I got for a R-2R ladder with trimpots ? (my temperatur range will be 20-40°C most of the time I think)I'd rather have a parallele interface, that probably will be easyer to handle at 3MHz than some serial one. I use a 160MHz cortex mcu so serial might work thought.Thx,J.

author: hubi
author_rank: Regular Contributor
timestamp: May 18, 2023, 08:07:23 am
content: Here is a design for the RP2040https://datasheets.raspberrypi.com/rp2040/hardware-design-with-rp2040.pdfusing resistors for the DAC. See page 20 for details on how the divider provides (close to) the 0.7V required. There are Kicad files available fromhttps://datasheets.raspberrypi.com/rp2040/VGA-KiCAD.zip.

author: Benta
author_rank: Super Contributor
timestamp: May 18, 2023, 06:22:25 pm
content: Quote from: Jaunedeau on May 18, 2023, 06:11:16 amI don't understand this sentence. Please clarify.thx.
Cheap Streaming USB Oscilloscope - Page 1
Forum section: electronics / beginners

author: chris9000
author_rank: Contributor
timestamp: February 04, 2017, 11:14:08 am
content: Hi,Just wondering, I'm looking for a streaming USB scope (so that the scope transmits all data directly to the computerover USB, rather than using a small internal memory).I think a bandwidth of 10MHz or so would be fine.I was hoping to pay < $100 or so, but maybe that's not possible?CheersChris

author: Gyro
author_rank: Super Contributor
timestamp: February 04, 2017, 12:28:16 pm
content: As far as I'm aware there are only a couple of USB scopes that act as 'dumb' USB streamers, they are the Hantek 6022be and the Sainsmart DDS140...https://www.eevblog.com/forum/testgear/hantek-6022be-20mhz-usb-dso/https://www.eevblog.com/forum/testgear/sainsmart-dds120-usb-oscilloscope-(buudai-bm102)/The other contenders are the Owon VDS1022(I) (sub $100) and the Diglent Analog Discovery ($more)...https://www.eevblog.com/forum/testgear/owon-vds1022i-quick-teardown-(versus-the-hantek-6022be)/(can't find the Diglent teardown thread)These second two have much more on-board inteligence, triggering etc. which makes them able to achieve higher sample rates, but less suitable if you're specifically looking for a basic streaming device.

author: chris9000
author_rank: Contributor
timestamp: February 04, 2017, 01:27:28 pm
content: Thanks a lot!, I'm going to look through all those now.
Cheap way of verifying radio transmitter tx frequency (to avoid interference) ? - Page 1
Forum section: electronics / beginners

author: e100
author_rank: Frequent Contributor
timestamp: November 29, 2016, 01:40:03 pm
content: I was thinking of buying the 902 to 928 MHz United States ISM version of the Xbee and flashing the firmware for the Australia ISM band which has a much narrower range from 918 to 926 MHz.We have cellular carriers operating either side of this range so I'd like to be extra sure that I'm not accidentally transmitting where I shouldn't be.Is there a cheap way of verifying the transmit frequency without buying a spectrum analyser. I'm probably only need to do the check once, so a breadboard solution would be OK.Mike

author: tggzzz
author_rank: Super Contributor
timestamp: November 29, 2016, 01:46:43 pm
content: What makes you think you can flash just that parameter?If you want to do a proper job, you'll have to measure not only the carrier frequencies, but also the amplitude of sidebands and harmonics.Almost certainly cheaper and more defendable to just buy the right device in the first place.

author: e100
author_rank: Frequent Contributor
timestamp: November 29, 2016, 02:00:34 pm
content: Quote from: tggzzz on November 29, 2016, 01:46:43 pmDigi makes the Australian specific firmware.http://ftp1.digi.com/support/firmware/pcn.xbp900.20110119.pdfMost resellers just sell the default US version or don't specify the version.Digi provide a utility for flashing the firmware.

author: Kelbit
author_rank: Regular Contributor
timestamp: December 08, 2016, 05:36:34 am
content: In a pinch, I've used anRTL-SDR stickas a makeshift spectrum analyzer when caught without one. Not nearly as good as a real spectrum analyzer, but it costs $20 and fits in a laptop bag.

author: kripton2035
author_rank: Super Contributor
timestamp: December 08, 2016, 07:14:22 am
content: Quote from: Kelbit on December 08, 2016, 05:36:34 am+1
Cheap wifi camera with very clear sound quality (do not care about video) - Page 1
Forum section: electronics / beginners

author: sairfan1
author_rank: Frequent Contributor
timestamp: December 09, 2019, 04:51:15 pm
content: I'm looking for Wifi camera with very sensitive mic and clear sound quality, does someone know any specific in North America?I do not care about video, I will remove camera from the module as i need to trigger some device from audio activity, or is there some DIY

author: SL4P
author_rank: Super Contributor
timestamp: December 09, 2019, 11:57:41 pm
content: I think the device you’re looking for is called a ‘microphone’ ?

author: sairfan1
author_rank: Frequent Contributor
timestamp: December 10, 2019, 02:28:59 pm
content: No, I'm looking for wifi camera module that has audio capability as well, I bought some but they have very poor sound quality, i believe they used just ADC for audio, after trying 4 different camera modules i thought to get help on it.There are some expensive ones like NEST, but I'm looking for cheap solution,

author: SL4P
author_rank: Super Contributor
timestamp: December 10, 2019, 07:27:07 pm
content: QuoteI must be missing part of the story.Audio is generally about four times simpler to capture than video.
Need cheaper tools to install a Harwin Datamate connector - Page 1
Forum section: electronics / beginners

author: nidlaX
author_rank: Frequent Contributor
timestamp: May 02, 2017, 04:23:24 am
content: I made the mistake of damaging one of these secure plugs by Harwin:https://www.digikey.com/products/en?mpart=M80-8892005&v=952Now, I'm looking to assemble an affordable set of tools to build a new plug (buying the DMC stuff is out of the question). For the crimping tool, I'm thinking of using this el cheapo 4-indent crimper:https://www.amazon.com/gp/product/B003WRJATU/However, I don't know what to use for the insertion / removal tool. Does anyone have any recommendations for how I can do this plug job without breaking the bank?

author: LouisS2p
author_rank: Newbie
timestamp: May 02, 2017, 09:57:33 am
content: For a critical product I would recommend rebuilding the connector with a new plastic housing. Indeed, even with Harwin's tools it is possible to damage the plastic shape used to retain the sockets.In any case you can pull out the socket using a round and pointy tool. You can insert a new one using a flat plier pinching the cable and in contact with the metal back end of the socket.

author: nidlaX
author_rank: Frequent Contributor
timestamp: May 02, 2017, 11:07:46 am
content: I'm definitely buying a new housing since I damaged mine by forcing two pins out. It would be nice to have a removal tool in case I miswire the plug or need to change the layout sometime down the line.

author: cowana
author_rank: Frequent Contributor
timestamp: May 02, 2017, 11:11:20 am
content: Even using the official removal tool has a fairly high chance (50%?) of damaging the plastic part of the plug - the internal circlips that grab onto the pin are pretty much single use. If you're planning to remove more than one pin, it's usually best to just replace the entire plastic part.
Cheapest DIP glue logic - Page 1
Forum section: electronics / beginners

author: mrpsychotic
author_rank: Contributor
timestamp: December 02, 2010, 06:37:45 am
content: I am looking to by some glue logic chips to prototype in so they must be in dip packages. I also want them to be cmos chips and not ttl. I am looking for which family of logic is the cheapest and for a good place to by them on the cheap. I don't care about the specs that much in terms of speed by I would hope for 5V and the ability to supply 15mA or more. The reason I am asking instead of finding the answers for myself is that I have already tried looking but there seem to be so many families that are very similar and I cant come to a conclusion. Ii was hoping that somebody who had some experience working with them would have some insight into me question.

author: EEwannabe
author_rank: Contributor
timestamp: December 02, 2010, 07:36:55 am
content: Are you looking for the 4000 series?http://en.wikipedia.org/wiki/4000_series- Patrick

author: CryptLordGR
author_rank: Contributor
timestamp: December 02, 2010, 09:27:45 am
content: As you want also to drive 5 V you could use the 74HCTxxx which are CMOS based and can work also with the power levels of the ttl

author: mikeselectricstuff
author_rank: Super Contributor
timestamp: December 02, 2010, 10:33:49 am
content: 74HC and 4000 series are the most commonl and cheapest. 74HC is faster, 4000 has wider supply voltage range of 3-15V

author: Zero999
author_rank: Super Contributor
timestamp: December 02, 2010, 06:28:37 pm
content: The 4000 series doesn't meet that specification because the output current is too low.74HC is good because it has a supply voltage range of 2V to 6V. HCT is the same but TTL compatible so only rated for 4.5V to 5,5V. I prefer 74HC because I don't have any TTL gates.
Cheapest ESP32/ESP8266 competitors with built in WiFi support? - Page 1
Forum section: electronics / beginners

author: YurkshireLad
author_rank: Frequent Contributor
timestamp: May 01, 2021, 11:23:40 pm
content: Silly question but what's the cheapest ESP32/ESP8266 competitor with built in WiFi support? I'm currently playing around with ESP32s and ESP8266s and I was wondering what else is in this space. I should trawl through the various STMs to see what they offer. I know I could buy a separate WiFi module and connect it to pretty much anything.Apparently my collection of ESP32s and ESP8266s are currently wired up to projects on hold and I'm too lazy to record their pin diagrams and disconnect them!

author: JustMeHere
author_rank: Frequent Contributor
timestamp: May 02, 2021, 12:43:42 am
content: Probably not going to find much cheaper than the $3 or so for the ESP32.

author: rsjsouza
author_rank: Super Contributor
timestamp: May 02, 2021, 01:21:27 am
content: Indeed. The other module family I know (Wilink) is quite more powerful but much more expensive.https://www.mouser.com/new/texas-instruments/ti-wilink-8-combo-solutions/

author: YurkshireLad
author_rank: Frequent Contributor
timestamp: May 02, 2021, 05:41:00 pm
content: Thanks all. I'll stick with ESP8266s and ESP32s due to familiarity.

author: Renate
author_rank: Super Contributor
timestamp: May 02, 2021, 06:34:18 pm
content: It's a different animal, but the Raspberry Pi Zero W is pretty nifty at $10.https://www.microcenter.com/product/486575/raspberry-pi-zero-wIt can't be beat when you actually need the HDMI output.There used to be a in-store promo for $5 (1 per visit) and I managed to collect a lifetime supply.

author: Doctorandus_P
author_rank: Super Contributor
timestamp: May 08, 2021, 12:49:35 pm
content: EEVblog #1056 of the Digilent Open Scope MZ has some kind of Microchip module for WiFi.@05:19https://www.eevblog.com/2018/02/15/eevblog-1056-digilent-open-scope-mz-review/