hybridfree/eevblog-posts huggingface dataset:
Wide voltage input - Page 1
Forum section: electronics / projects

author: Jr.Maxwell
author_rank: Contributor
timestamp: February 20, 2020, 11:58:26 am
content: Hello membersWhile designing an Interface for a product I've noticed that the product has a wide range voltage input, it made me think about the applications for wide range voltage input.What are applications for having a wide range input? I can imagine that this is helpful when using batteries as power supplies, as the voltage keeps on changing. Are there any OTHER aplications you can think of that are usefull with a wide voltage input?Thank you for your time

author: SiliconWizard
author_rank: Super Contributor
timestamp: February 20, 2020, 02:28:59 pm
content: Maybe you should define what you mean by "input" here.The example you're giving is with power sources. Whereas that sometimes requires a "wide" range, batteries are usually not a particularly significant example, as typical batteries' voltage doesn't vary THAT much (for instance, for a typical LiPo cell, that would be ~3.0V to 4.2V - even for multi-cell batteries, that will usually be just a few Volts - I don't call that "wide", but hey.)Typical WIDE voltage inputs: multimeters, scope channels, acquisition systems in general.Multimeters can usually deal with voltages as low as a few µV (or less for the high-end ones) up to 1000V or above! That's what I call wide!

author: ArthurDent
author_rank: Super Contributor
timestamp: February 20, 2020, 03:26:02 pm
content: Quite often there are pieces of TELCO equipment that may be required to run from either 24 or 48 volt battery supplies and having one power supply that will operate over the entire range without changing voltage selection switches is a big plus.Most plug-in wallwarts are designed to operate from either 120VAC or 240VAC to allow the unit to be used worldwide with one supply, making it cheaper to produce and more foolproof.
Wideband Amplifiers (partial text?) - Page 1
Forum section: electronics / projects

author: T3sl4co1l
author_rank: Super Contributor
timestamp: January 03, 2015, 04:03:12 pm
content: For those of you interested in wideband and lightly tuned / peaked sorts of reading:http://extras.springer.com/2006/978-0-387-28340-1It looks like the book is still in print (for a characteristically optimistic price, at that), and you're only supposed to be able to download supporting materials and excerpts? This directory looks pretty useful though.Tim

author: Marco
author_rank: Super Contributor
timestamp: January 03, 2015, 08:03:40 pm
content: He also has a bit on the design of a scope front end.

author: moffy
author_rank: Super Contributor
timestamp: January 05, 2015, 11:00:47 pm
content: Thanks for the post. Looks interesting.
Wien Bridge oscillator - Op Amp types? - Page 1
Forum section: electronics / projects

author: Solder_Junkie
author_rank: Frequent Contributor
timestamp: February 27, 2025, 10:46:46 am
content: I built a two tone oscillator based on the one by Elecraft. Their design use LMC6482AIN Op Amps (rail to rail types). The harmonics of a single tone are around 50 dB below peak output. If I swap the Op Amps to TL072 (not rail to rail), the harmonic content increases significantly to around 30 dB below peak.While I have no issue using the LMC types, I cannot see why using the more common TL072 Op Amps increase the harmonic levels so much. It doesn't matter whether I use TL072s for either the oscillator or the buffer, the increased harmonic level is the same. The supply is a little low at 9V (min level suggested for the TL072 is 10V) increasing the supply to 16V made no difference.The basic oscillator circuit is attached. The Elecraft manual can be downloaded at:https://ftp.elecraft.com/Mini%20Modules/Manuals%20Downloads/2T-Gen_Manual_Rev_B.pdfAny ideas?ThanksSJ

author: Kleinstein
author_rank: Super Contributor
timestamp: February 27, 2025, 11:36:47 am
content: Already harmonics at -50 dB is not great for a wien bridge oscillator. -30 dB harmonics suggests a real issue, like the amplitude regulation not working and the OP-amps clamping instead. This could be more an issue with the more asymmetric output range of the TL072.

author: Solder_Junkie
author_rank: Frequent Contributor
timestamp: February 27, 2025, 11:40:44 am
content: Quote from: Kleinstein on February 27, 2025, 11:36:47 amUsing an LMC6482 as the oscillator and a TL072 as the split rail/buffer (see the Elecraft manual for the full circuit) still produces 20 dB more harmonics. The issue relates to using the TL072 type of Op Amp as opposed to the "rail to rail" LMC one. It is possible that the TL072 op amps I have are "fakes" but as they basically work it is not likely.

author: Kleinstein
author_rank: Super Contributor
timestamp: February 27, 2025, 11:50:44 am
content: There were a few cases where fake TL072 were sold from China. The reports I heard of had kind of slightly improved lm358 OP amps - so kind of working, but relatively poor performance (low speed and cross over distortion). With an LM358 OP-amp I would not be surprised to see distortion already -30 dB could be visible on the scope.

author: Doctorandus_P
author_rank: Super Contributor
timestamp: March 01, 2025, 09:25:57 am
content: How do you even get a symmetrical output if you use a rail splitter for the wien bridge, and then reference the oscilloscope to the negative power supply?
Wierd behaviour with Lithium battery - Page 1
Forum section: electronics / projects

author: Sarthdave
author_rank: Newbie
timestamp: December 23, 2018, 06:40:48 am
content: Hello,I a using a TP5410 based lithium battery charging and boost converter circuit. The circuit is intended to charge the lithium battery and also provide a stable 5V using its internal boost converter. Currently I am experimenting with two types of lithium batteries.1. A samsung 18650 cell2. A BL-5C type flat cellThe 18650 have an internal PCM circuit and the BL-5C internal PCM has been removed. I deliberately installed a separate PCM circuit module in both the batteries.While testing, When I short the 5V to GND using the 18650 cell, the circuit protects it and once the short is taken away, the system starts to function normally.However, in case of the same experiment with the BL-5C cell, the PCM also protects it from short but after the advent of a short circuit, the system does not produce 5V again. I probed the battery for voltage but it shoes 0V. The wierd thing is the once I remove the battery from the system and re attach it, everything starts to function normally.My reading on this is that something, somewhere is causing the battery to latch after a short and can only recover once it has been re inserted.Any ideas on this one? Please share your thoughts on this.

author: timpattinson
author_rank: Contributor
timestamp: December 27, 2018, 03:01:44 am
content: Is there a resettable fuse hidden in the BL-5C?

author: Sarthdave
author_rank: Newbie
timestamp: December 27, 2018, 07:14:58 am
content: Hello tim,Thanks for the response. After removing the PCM, It seems tome like a plain cell. I dont have any information about the cell's internals (no datasheet) so I dont know whether the resettable fuse is inside or not.
Wierd WiFi Connectivity Issues - Page 1
Forum section: electronics / projects

author: Marc M.
author_rank: Regular Contributor
timestamp: March 09, 2013, 09:54:46 am
content: I've been working on an Arduino based data logger to collect data from our CNC machining centers and dump it over WiFi to the office. I'm using the WizFi based module made by tinyosshop.com. I've got 2 prototypes installed in 2 machine centers that sit right next to each other (1 Toyoda, 1 Niigata). Both prototypes are identical and enclosed in grounded die-cast enlosures. The problem I'm having is that they work decently without any antenna connected. The time it takes before it drops out varies from a few minutes to sometimes a day or two. With an external antenna attached, they lose their connection and can't reconnect. As soon as I remove the external antenna, they have no problem re-establishing a connection. If I pull the RSSI readings directly out of the WiFi modules I get around -78db without an antenna, and right around -60db with either a rubber duck or the magnetic mount antenna I intended to use. So with an antenna I'm gaining almost 20db and it drops out.I thought there might be an interference issue so I purchased a RF Explorer to look for any signs of interference in the band. Unfortunately, it doesn't show anything out of the ordinary. All WiFi signals are centered on channels 1,6, and 11, nothing inbetween. During the holidays we only had a couple of people in the shop and it still dropped so I've eliminated Bluetooth/Cell phone issues. In the area of the 2 machines with the rubber duck adapted to the RF Explorer I'm showing a peak of -64db on 11, -79db on 6 and -70db on 1. I played around with trying to force the modules to channel 11 but never could get them to accept the AT command for it. But something changed because the module installed in the Toyoda is now working most of the time. The Niigata still won't stay connected with an external antenna.I swapped out the WiFi board in the Niigata with a different one and I still get the same result. I'm pretty much out of ideas so I'm hoping someone here might be able to offer some insight.
Wifi adapter (mini PCIE) to PCIE X1 schematic - Page 1
Forum section: electronics / projects

author: binary_99
author_rank: Newbie
timestamp: April 30, 2018, 10:30:26 pm
content: Hi all,Long time Dave watcher, first time poster.As the title says, I'm looking for advice or a schematic to make my own mini PCIE to PCIE X1 adapter for a wireless card. I know they can be bought off Ebay for less than $10, but, for sh!ts and giggles I'd like to etch my own board to fit into the PCIE X1 slot on my computer (plus I'd like not to have to wait 8 weeks for it)I made a board based on the schematic from this sitehttps://boundarydevices.com/wp-content/uploads/2014/12/PM2-C.pdfand......it doesn't work. There are resistors and talk of capacitors for the Tx/Rx lines but do not give details of values.If anyone is able to give any assistance I would much be appreciative. I don't need the USB port or LEDS, I just would like the bare bones to get the wireless card to work in my computer.Thanks!

author: ANTALIFE
author_rank: Frequent Contributor
timestamp: April 30, 2018, 11:28:02 pm
content: Can you give us a picture of the board you made?This project would be dealing with some "high-speed" signals so your board design would need to take things like impedance matching & trace lengths into account

author: binary_99
author_rank: Newbie
timestamp: April 30, 2018, 11:55:34 pm
content: Thanks for the reply ANTALIFE,Yeah, the length matching. I did it to the TXp and TXn lines, but neglected to do it on the RX lines so they were out by about 100mils or so. I don't think that was the issue with it not working at all though?This was a project I was hoping I could just Google and find a layout someone else had done. Imagine my surprise.I'll attach the PCB layout, but please forgive my barbaric crudeness. I only did one via and the others I needed to do I just went around the edge of the board.....don't laugh! lol I also have some jumpers on there to cross traces......don't laugh!

author: binary_99
author_rank: Newbie
timestamp: May 01, 2018, 12:04:55 am
content: And just for further information. I installed a jumper wire on the motherboards pcie x1 slot from PRSNT1# to PRSNT2#.

author: Bratster
author_rank: Frequent Contributor
timestamp: May 01, 2018, 01:58:57 am
content: Are you sure your WiFi card is actually pcie?I'm pretty sure the mini pcie port has usb as well, so the card may use that.Sent from my Moto x4 using Tapatalk

author: Monkeh
author_rank: Super Contributor
timestamp: May 01, 2018, 02:29:05 am
content: That layout is just not going to work for PCIe.It's really not practical to do this with a home etched board.Quote from: Bratster on May 01, 2018, 01:58:57 amVery unusual and unlikely.
Wifi Antenna and right angles - Page 1
Forum section: electronics / projects

author: johnnyfp
author_rank: Frequent Contributor
timestamp: March 15, 2014, 12:59:14 am
content: Hi,I'm putting together a Wifi enabled board and have a ceramic antenna positioned close to the wifi chip. The datasheet says that sweeping curves must be used to connect to the antenna and that sharp corners must be avoided to stop any reflections.Now the circuit requires a couple of caps and inductor on the line. If I arrange the caps as shown, and try and cheat, is that still regarded as a right angle or sharp corner?

author: Gustav
author_rank: Newbie
timestamp: March 15, 2014, 01:30:18 am
content: Using a cap as a corner point should be fine. I have used it in a couple of designs with out any noticeable effect, and i also know TI uses it on their reference design for the CC3000 module.

author: KJDS
author_rank: Super Contributor
timestamp: March 15, 2014, 10:44:14 am
content: If you want perfection, then use a mitered corner. I really don't like putting components on corners, it just adds to the to the stray excess capacitance to ground at a right angle bend. I suspect it won't make much difference, probably less difference than placement accuracy of the antenna ceramic.
WiFi-Audio-Device Idea.  - Page 1
Forum section: electronics / projects

author: Kalu
author_rank: Newbie
timestamp: November 24, 2015, 07:21:07 pm
content: Hi,I own a Spark Photon, and some ESP8266 Modules.And I noticed that they have an I2S interface.Also there exist I2S Amps (IS31AP2121, TAS5713).So i guess it might be possible to create a DLNA (or AirPlay) Device with such Chips and Modules.Sadly i'm not an electrical engineer, i'm a software engineer.Does anyone have a clue about simple Modules to build a Hardware Prototype and then write the software and so on?Thanks.

author: kripton2035
author_rank: Super Contributor
timestamp: November 24, 2015, 08:01:52 pm
content: http://www.esp8266.com/viewtopic.php?f=13&t=99http://bbs.espressif.com/viewtopic.php?t=553
Wifi audio hub  - Page 1
Forum section: electronics / projects

author: chaminda12001
author_rank: Newbie
timestamp: May 08, 2019, 05:33:07 am
content: Wi-Fi audio hub for headphones and speakers. It lets instantly share wireless audio with multiple simultaneous listeners using any earbuds, headphones or powered speakers. I need a help design this project using VHDL. This is going to be system on chip design. I need some help in designing ﻿

author: cat87
author_rank: Regular Contributor
timestamp: May 08, 2019, 11:44:15 am
content: First, welcome to the forum.Secondly, if you want help with designing stuff, a one-liner doesn't really go well with engineers.You way wireless... ok, is that Bluetooth, Wifi, will you make your own wireless protocol ?For headphones AND speakers.... what kind of speakers? What power levels are we talking about?How will the audio be stremed to the hub ?And more importantly, what do you actually need help with?

author: NiHaoMike
author_rank: Super Contributor
timestamp: May 08, 2019, 02:26:07 pm
content: You can probably do it with an ESP8266 or ESP32 running some custom firmware.

author: cgroen
author_rank: Unknown
timestamp: May 08, 2019, 05:03:45 pm
content: Quote from: NiHaoMike on May 08, 2019, 02:26:07 pmOr any other random piece of electronicsNo need to dream up solutions when there is absolutely ZERO information provided in the original post....

author: NiHaoMike
author_rank: Super Contributor
timestamp: May 08, 2019, 05:42:29 pm
content: Quote from: cgroen on May 08, 2019, 05:03:45 pmThe ESP8266 is the cheapest thing I can think of that has both Wifi and I2S. I like the idea of low latency HD audio over Wifi, basically an open source alternative to Nvidia's implementation of HD audio over Wifi.

author: cgroen
author_rank: Unknown
timestamp: May 08, 2019, 05:59:27 pm
content: Quote from: NiHaoMike on May 08, 2019, 05:42:29 pmI'll just reply with the same reply once moreNo need to dream up solutions when there is absolutely ZERO information provided in the original post....
Wifi - Bluetooth RF Interference - DC Power. - Page 1
Forum section: electronics / projects

author: DW1961
author_rank: Frequent Contributor
timestamp: August 19, 2020, 12:08:03 am
content: A few month ago I had a problem that I fixed by putting space between my class D amp/BT receiver combo and my router. I didn't know what it was until I started trouble shooting.So, I was getting interference between the amp and the router. I put space between them and the interference stopped.The Amp has an integrated BT 5.1 receiver and is Class D. It comes with a power brick. It was about 18" away from my Motorola modem/router. Every time I would load a web page using wifi, the music would stutter. After putting about 3' of space between the Class D amp / BT package and the Router, the stutter stopped.What intrigues me is that the wifi signal was interfering with the amp's BT connection, so what did the manufacturer of the amp forget to do, or not do well? (I believe 2.4Ghz is the same frequency that BT uses.)(I'm testing another Class D amp right now and I have it literally 6" away from the router, an I get no interference at all. It's the same similar package, Class D amp/BT 5.1 integrated, just a different vendors build. So, that's why I'm interested.)
WiFi connected Weather station - Page 1
Forum section: electronics / projects

author: Mikey
author_rank: Regular Contributor
timestamp: October 12, 2014, 09:10:19 am
content: I have been working on a pcb for a while for a wifi connected weather station.The pcb is more or less just a breakout board for an Electric Imp, so there isn't that much in it, but I still managed to learn a fair deal while making it.As you will spot right away, is the missing names for the components, this is because the text was too small for iTead to print, so instead of telling me, they just removed it and finished the pcb's.For the first time, I also got a stencil made, and now I just wait for the last few parts so I can test it and reflow the smd components.During the making of this PCB I also had to learn how to make my own component in Eagle, and so far everything seems to line up just fine.To try and keep my excitement in check, I just had to put some more components on, without soldering them in, just to get a better idea about how the finished thing would look.While the silkscreen is a bit low quality, I am happy to see the traces are a lot better.

author: LukeW
author_rank: Frequent Contributor
timestamp: October 12, 2014, 12:56:37 pm
content: Looks nice.You don't often see those smooth curved corners on most layouts, except for controlled-impedance RF stuff. But of course it doesn't hurt anything when used in a slow circuit, and it looks really sleek.

author: Mikey
author_rank: Regular Contributor
timestamp: October 12, 2014, 01:18:01 pm
content: Quote from: LukeW on October 12, 2014, 12:56:37 pmI have no idea about when to use them or when not to use them, I just liked the look of it, and figured with the signals I am going to use them for, it would not really matter.

author: David Hess
author_rank: Super Contributor
timestamp: October 12, 2014, 01:50:52 pm
content: Quote from: LukeW on October 12, 2014, 12:56:37 pmI used to do all of my boards this way. Transmission line construction does sometimes help with low frequency circuits as far as making them more resistant to RFI.

author: Mikey
author_rank: Regular Contributor
timestamp: October 13, 2014, 03:14:59 pm
content: Quote from: David Hess on October 12, 2014, 01:50:52 pmUsed to? Why did you stop?

author: Mikey
author_rank: Regular Contributor
timestamp: October 13, 2014, 04:23:14 pm
content: Quote from: mojo-chan on October 13, 2014, 04:10:14 pmI am going to use a constant output from my garage door opener, but it could easily run for a while on a battery. When connected to wifi and transmitting it uses about 40-45mA, and if I wanted to, I could put it into sleep.

author: David Hess
author_rank: Super Contributor
timestamp: October 13, 2014, 05:29:50 pm
content: Quote from: Mikey on October 13, 2014, 03:14:59 pmIt takes more time at least the way I was doing it. The photo below shows a poor example (selected based on being within reach) although it was one of the first boards I laid out. I think the smallest line size shown is 8 mils but most are 12 mils or thicker. Later boards were a lot more complex and as I got better at it, included more layout features.
WiFi dongle antenna modding - Page 1
Forum section: electronics / projects

author: Alex8
author_rank: Newbie
timestamp: June 24, 2022, 06:31:45 pm
content: So, this is a bit of an oddball project, for reasons I don't think are too interesting to most, i need to get one of those tiny WiFi/BT USB dongles and somehow replace the PCB trace antennas with IPX connectors.Now, I have little to no experience with RF, so i'm a bit out of my element here, so I'm wondering if anyone here might have the expertise to kinda evaluate the possibility of this thing, as well as potentially walking me through any necessary considerations.Thanks in advance!Alex

author: Haenk
author_rank: Super Contributor
timestamp: June 24, 2022, 07:16:38 pm
content: How about using a USB WiFi dongle with attached antenna, that would make things really easy...Likehttps://www.kaufland.de/product/432053911(Just a random link, plenty of other sellers available; maybe also look on Amazon or Aliexpress...)

author: Alex8
author_rank: Newbie
timestamp: June 24, 2022, 10:28:41 pm
content: Haven't seen any of that variety with bluetooth also built in, i'm pretty sure that'd require multiple antennas, but the prospect is indeed promising, the key is that it's crucial that the board, stripped from USB housing and plastic, is as tiny as possible. I will investigate further, thanks for the tip!
WiFi home automation components - General question  - Page 1
Forum section: electronics / projects

author: WattsThat
author_rank: Frequent Contributor
timestamp: February 16, 2025, 02:24:42 pm
content: I’m looking to create a one of a kind thermostat system for a house I’m remodeling. It’s a combination of hot water baseboard heat with a H/W radiant floor zone. I could do it with many hard wired individual thermostats but would like to build something integrated just because it’s a challenge. I’m thinking I’ll start with an ESP32 Arduino due to the amount of support it appears exists for this type of project.I see both Zigbee and WiFi battery powered thermometers (with humidity) everywhere for less than $10. These would make a great sensors as I could discretely apply them in the areas to be controlled.It appears the Zigbee protocol is supported on the ESP32 but for the life of me, I cannot figure out the WiFi device protocol used. Is it MQTT? I’ve ordered one each of Zigbee/WiFi devices to play with and figure out if it’s feasible to use them as the sensors.It’s probably my search terms that leads me to dead ends. I’d hate to have to resort to WireShark and have to deal with that low of a level only to just a read a temperature every minute. Has anyone out there worked with these types of devices and can get me pointed in the right direction?Oh, yeah, I know about Home Assistant and all the open home automation stuff out there. That’s not where I want to start. It may be where I end up but I wanted to start out bare metal so to speak and see how far I can get. Learning new tech (to me ) is the reason for the journey as much as the end result.

author: Tation
author_rank: Regular Contributor
timestamp: February 16, 2025, 07:40:26 pm
content: WiFi is not feasible provided you want the sensors to be battery powered, as is my case.Apart from Zigbee there is also Bluetooth Low Energy (BLE), supported by ESP32 and, of course, by many other devices, including Raspberries and other SBCs.There's also a proposed open standard for the protocol to be used to broadcast sensor data thru BLEhttps://bthome.io/. You can receive the BTHome broadcasts from the sensor with an ESP32 based device, or with a Raspberry Pi with Python or whatever, and then report them to an MQTT broker, locally or via WiFi/Ethernet. Such BTHome protocol is also understood by Home Assistant, in case, in the future, you are interested on it. In any case, once the data has been "MQTT'ed", it can be processed in many ways, with HA or other systems.Shelly is producing now many devices supporting BLE & BTHome. Its gen3 WiFi relays can even be used as BTHome gateways for any BTHome device. No affiliation with Shelly, but a happy customer.

author: Tation
author_rank: Regular Contributor
timestamp: February 17, 2025, 07:29:57 am
content: Also, the Xiaomi Temp & humidity monitor 2 can be reflashed (search for Telink Flasher) to report its measurements using BTHome.
WiFi Light switch in a wall box with no neutral - Page 1
Forum section: electronics / projects

author: JacoRoselt
author_rank: Newbie
timestamp: May 24, 2018, 06:41:30 am
content: Hi,I found the attached schematic on another forum. It describes a way to install a WiFi controlled light switch, which requires a live and neutral AC connection, in a wall box that does not have a neutral connection. It looks a bit weird to me.Will it work and what are the possible problems with a setup like this?

author: Whales
author_rank: Super Contributor
timestamp: May 24, 2018, 06:46:41 am
content: That will work for incandescent bulbs, but fluoros and LEDs will flicker or light dimly. EDIT: the cap bypassing the bulbmightfix this.The circuitry in the wall-plate does actually have a neutral going to it. Wires normally have a resistance much smaller than our circuits/loads, so we simplify things and assume this resistance does not exist. Similarly in this situation: the unlit lightbulb and capacitors will have an resistance much lower than the circuit in the switch. Enough current leaks through the light and capacitors to power the circuit, but not enough to light the bulb.EDIT: from a safety point of view it ispossibleto use caps small enough to minimise any electric shocks given to humans (when they change bulbs and slip a finger), but you'll need to be clever in how you design in the in-switch circuit.

author: james_s
author_rank: Super Contributor
timestamp: May 25, 2018, 09:28:12 pm
content: If you can access the boxes, say from the attic then a better idea would be to run another cable that has a neutral. The solution outlined there may work if no other is available though.
WiFi Module for CNC Power Supply (Sinilink ESP8585H16) - Page 1
Forum section: electronics / projects

author: JoanBS
author_rank: Contributor
timestamp: May 23, 2025, 01:27:19 pm
content: Hi, I've built a switching power supply with an XY-6014 CNC module and a Sinilink WiFi module for remote control.The power supply has a sleep function that, after a period of inactivity, switches the display to weather station mode (it's silly, I know, but I didn't request it).The problem is that when the power supply's sleep function is activated, the display shows the current date and time, synchronized via the WiFi network, but it doesn't show the temperature and local weather. I assume this requires connection to a weather station.I have a home weather station connected to my WiFi network and would like to view the data through this power supply's display, but despite this option being advertised on Aliexpress, I haven't found a way to implement it.I'd like to know if anyone uses this module and has managed to get it to work properly. Thanks.
WiFi module test strategies - server response - Page 1
Forum section: electronics / projects

author: hcglitte
author_rank: Regular Contributor
timestamp: August 25, 2022, 05:59:17 am
content: Hi,I currently use cc3100mod wifi module as a client. I open a socket, connect to server, send and receive.All these actions are blocking, and I use a timeout in case things don't go well.In order to test the timeout for the mentioned actions (or errors), I think I would need to control the wifi access point or the server somehow. I would need to intentionally give error responses from the server and delay the various responses from server.I have no idea where to start. Is there any test systems available which give me full control for this requirement? Any help is appreciated.
WiFi Project - Page 1
Forum section: electronics / projects

author: ebrkw
author_rank: Newbie
timestamp: April 13, 2017, 08:50:07 pm
content: Hello Everyone,I was brainstorming for a project that would involve taking in a form of real-time data and performing DSP on that signal. Once that was completed, I would like to send the real-time data values to an Android Mobile App to plot the data. Is it possible to create a WiFi TCP/IP or UDP connection between an Arduino MKR1000 (coded in C/C++) and an Android Mobile App (coded in Java)? I understand that this may not be a typical electronics project, but I know there is a huge supporting community here at EEVBlog so maybe someone has experience in this field. If so I'm very interested in finding sources on this specific combination of microprocessor to Android device if there are any.

author: frozenfrogz
author_rank: Frequent Contributor
timestamp: April 14, 2017, 12:10:23 am
content: The MKR1000 is basically an Arduino Zero with a wifi shield piggy-backed. It is capable of TCP/UDP, both P2P and AP mode should be possible.Just from the datasheet for the MKR1000 I would suggest you also take a look at the ESP8266MOD (ESP12F). This little thing is fast! It comes with 4Mb flash memory and there is good integration with the Arduino IDE (need to load additional board info first).ESP12F does support P2P and AP mode, can act as a small web server and features more than enough GPIO pins and I2C for most small to medium sized projects. I don’t want to persuade you at all cost, but I am a huge fan since I started using them a while ago!They are mostly advertised in context with NodeMCU and the LUA script based system, but the latter did not convince me at all.
WiFi range Extender help! Projects Help! - Page 1
Forum section: electronics / projects

author: JacobIsHere
author_rank: Contributor
timestamp: April 14, 2015, 07:12:56 am
content: Hello,I was wondering if there was a WiFi range extender could make. I live in a extended house and my bed room is all the down the other end of the house and the WiFi will not reach in there i have (my mum) bought WiFi range extenders from shops and none work, I am new in electronics and i don't know much but i would like to try to make one. if any one has an idea please comment on this post. Thank You!

author: GreyWoolfe
author_rank: Unknown
timestamp: April 14, 2015, 11:53:15 am
content: Working in GHz frequencies for a beginner will be very difficult. My suggestion is to do some research and buy a compatible WiFi router( 802.11G/N/AC, that matches what you are using) that can be put into repeater mode and use that. An alternative would be to reflash a compatible router with Tomato or DD-WRT. From what I understand, these firmware options will give you the ability to use the router as a repeater and, in some cases, actually allow you to increase the output power.

author: madires
author_rank: Super Contributor
timestamp: April 14, 2015, 12:28:07 pm
content: The best idea would be to find some router/WLAN expert in your area and let him do the configuration of the WLAN extender. In most cases it's also a good idea to buy a WLAN extender made by the same company as the WLAN router.

author: Kjelt
author_rank: Super Contributor
timestamp: April 14, 2015, 12:30:44 pm
content: Better than an extender is to add a wireless Acess Point (AP) if you can get a cat5e networkcable from your router/switch to your location that would be much better than an extender.

author: tggzzz
author_rank: Super Contributor
timestamp: April 14, 2015, 12:49:42 pm
content: You will not be able to (legally) make any such radio device. If you try and get it wrong, then expect to get The Authorities paying you a visit!Consider using a pair of powerline LAN devices which plug into mains sockets and transmit the LAN signals over the mains wiring. Connection between the devices and router/computer is via standard LAN cable.

author: JacobIsHere
author_rank: Contributor
timestamp: April 15, 2015, 12:24:37 am
content: thank you all for the feed back!

author: NiHaoMike
author_rank: Super Contributor
timestamp: April 15, 2015, 04:21:59 am
content: Look up "cantenna".
WiFi Reflow Oven - Page 1
Forum section: electronics / projects

author: danielrp
author_rank: Newbie
timestamp: May 28, 2019, 06:41:00 pm
content: Hi all,I recently started working in a reflow oven controlled remotely via WiFi. I know reflow ovens based on toaster ovens are not a new topic at all and also have some controversy, but it could result interesting for someone. I have the idea of doing a series of videos and just published the first one. The first one is just about the wiring diagram and how I assembled it, next will be some open loop results and a cooling system.https://www.danielrp.net/projects/proj-reflow-ovenCheers,Daniel.

author: abumbalough21
author_rank: Newbie
timestamp: May 30, 2019, 02:23:47 am
content: Looks like a really neat project. Like you mentioned in the video, the response time for those large resistive heating elements can be quite slow. I'm interested to see what kind of solution you come up with!

author: danielrp
author_rank: Newbie
timestamp: June 16, 2019, 06:24:21 pm
content: Just published a new "episode" of the reflow oven. It covers the cooling system:
WiFi TV Remote - Page 1
Forum section: electronics / projects

author: ColdKeyboard
author_rank: Contributor
timestamp: October 21, 2020, 06:02:40 am
content: This is a extremely simple project, but, it saved me so much time.One of the things that started happening way to often is, I'm not the one who is misplacing the TV remote but I'm always the one recruited to find it... which is not fun.So I built my own WiFi remote, it sits on a shelf and I interact with it with my phone and PC.https://youtu.be/XKWTu5t2lUAHonestly, I wish my smart TV had this feature since now I don't even need the remote that came with the TV.What do you guys think?

author: nuclearcat
author_rank: Unknown
timestamp: October 21, 2020, 06:56:49 am
content: Has same thoughts, but my smart TV(Sony) have such feature.But as usual - unreliable (first click after idle doesnt work, can't do powercycle sequence over long hold power-off button as on IR), over-proprietary and over-cloudified.So still might worth to do project similar to yours (only minor difference - i use mosfet to drive led), already did custom PCB for that.

author: ColdKeyboard
author_rank: Contributor
timestamp: October 22, 2020, 01:22:42 am
content: Oh that's awesome! I didn't know they started adding that to smart TVs. I thought it would be an awesome feature since my TV doesn't have it. But you're right, if implementation is not right... then it might be easier to just spin your own design.Please share your version once you have it up and running, I would love to take a look at it.
Wifi+bluetooth module - Page 1
Forum section: electronics / projects

author: Vipu
author_rank: Newbie
timestamp: March 27, 2015, 10:36:08 am
content: Hiiii friends,Have anyone worked on TiWi5 module??? Now I am working on TiWi5 module based project. How to interface this module with PIC microcontroller.If anyone have circuit diagram,please share it here. Thanks in advance.
Wig-Wag circuit using Two relaya and a capacitor - Page 1
Forum section: electronics / projects

author: rohmell
author_rank: Newbie
timestamp: January 30, 2016, 05:22:18 pm
content: Hi, I am looking for a schematic to build a wig-wag circuit. I have searched all round, and have found versions that use a 555 timer, multivibrator circuits that use transistors, an automotive-type flasher coupled to a relay, SCR-driven designs, etc.The one that I want is one that I recall seeing in Radio-Electronics magazine in the '80s, perhaps around '81?I tried to search for old RE magazines or articles, but no luck.The circuit that I am trying to find uses two multi-pole relays and a single electrolytic capacitor. I know that I built one and it worked perfectly, both relays cycled in equal on/off time ratios, etc.Alas, the one I build has been lost to time, and I want to recreate it.When I built mine, I used 4PDT 24V relays, and if I remember correctly, the design needed two poles from each relay in order to switch the single timing capacitor between them.Any help will be greatly appreciated!rohmell@yahoo.com (not scared of spam, have excellent filtering).

author: rdl
author_rank: Super Contributor
timestamp: January 30, 2016, 07:21:47 pm
content: I have no idea what you mean by "wig-wag", but many old issues of Radio-Electronics are available at the Internet Archive.https://archive.org/details/radioelectronicsmagazineFrom your description it sounds like you want a multivibrator. One can easily be built with two transistors and a few other parts, but you will probably need additional circuitry to drive your load. Here is one example.http://www.instructables.com/id/Two-transistor-LED-Flasher-Circuit/

author: Gyro
author_rank: Super Contributor
timestamp: January 30, 2016, 07:43:23 pm
content: That's a term that I haven't heard in a long time ("wig-wag").If you're doing it just with two relays then I suspect that the electrolytic capacitor will need to be a bipolar one!

author: janoc
author_rank: Super Contributor
timestamp: January 30, 2016, 08:00:41 pm
content: You mean something like this?http://relayscircuits.blogspot.fr/2010/12/simple-oscillator-with-one-relay_02.htmlI have built one of these when I was a kid using two telephone relays salvaged from something. It is pretty easy to design your own - just realize that for the thing to oscillate the relays need to cut power to each other's coil.The capacitor is there only to slow down the oscillations - but it needs to be a fairly large value and bipolar, or the high voltage inductive spikes from the coils will kill it.
Will a hipot test of a power mosfet breakdown voltage cause permanent damage?  - Page 1
Forum section: electronics / projects

author: julian1
author_rank: Frequent Contributor
timestamp: June 27, 2023, 10:22:46 pm
content: Perhaps they shouldn't be recycled, or used for other tests?With a common/ordinary trip current - eg. at 5mA, or 10mA.

author: Conrad Hoffman
author_rank: Super Contributor
timestamp: June 28, 2023, 02:48:08 am
content: A full breakdown test of any semiconductor, save for protective devices, is apt to damage it. BJTs can be tested on a curve tracer for breakdown, but you typically stop the second you see an upward curve to the current. That's an extremely low current, probably nowhere near mA levels. Don't know if it's safe at all with MOSFETs, but I'd be very wary.

author: ArdWar
author_rank: Frequent Contributor
timestamp: June 28, 2023, 03:38:30 am
content: Some MOSFETs are avalanche rated. The datasheet will say so (with huge asterisks). The common 250uA IDSStest currentshouldbe fine.Unless you're talking about VGSbreakdown, which you should always treat DUT as toast.
Will a simple Peak detector with bleed reset ineviably slowly oscillate? - Page 1
Forum section: electronics / projects

author: 741
author_rank: Frequent Contributor
timestamp: August 27, 2021, 04:35:22 pm
content: I think what happens is it overshoots, then once the output decays below the true peak, it again overshoots...Given a LF sine wave input the response looks good "at a distance", however this peak "restores" with a periodic (1 or 2 seconds) classic RC decay and the "restore spike" is about 300mV amplitude.This seems (in retrospect) what would be expected. I never really thought about it until the comparator I was driving starting flashing its indicator LED at rougly 1Hz.I can't afford sufficient comparator hysteresis to swamp this effect. It would be better if I could have a smaller and faster overshoot - would feed-forward be worth trying? A smaller capacitor, larger resistor would help somewhat, but not enough.There are many solutions involving different Peak detect principles and/or more elaborate reset methods, but I was wanting a very simple design, which I why I chose this one.

author: mikerj
author_rank: Super Contributor
timestamp: August 27, 2021, 06:11:05 pm
content: Which op-amp are you using? Are you sure it's going to be happy driving a 10uF cap? 10uF seems pretty excessive for a peak detector.

author: spostma
author_rank: Regular Contributor
timestamp: August 27, 2021, 06:54:20 pm
content: I would raise the 'Z' ground vokage node a little using a voltage divider such that the divided voltage is a little higherthan the Opamp input offset voltage plus the maximum input noise voltage.Just experiment a little; I would start with a divider of 10K to +5V and 22R to GND, which yields 11 mV offset.
Will an alternative ic work - Page 1
Forum section: electronics / projects

author: Njackste
author_rank: Contributor
timestamp: October 25, 2021, 05:44:51 pm
content: I need to replace an ltc4054 but my local Farnell/rs don't have it but they have alternatives such as thishttps://ie.rs-online.com/web/p/battery-management/7328730.Will this work?Will any other alternatives that I can get locally work.Otherwise I'll just get it on AliExpress or eBay

author: mikerj
author_rank: Super Contributor
timestamp: October 25, 2021, 06:55:09 pm
content: The Maxim part provides a similar function but it is not pin compatible.

author: Njackste
author_rank: Contributor
timestamp: October 25, 2021, 08:23:53 pm
content: Thank you

author: wasyoungonce
author_rank: Frequent Contributor
timestamp: October 26, 2021, 07:03:33 am
content: Many other mfgrs copy ICs and they still retain the core part number...in this case "4054"....so a quick search for "4054 battery management"...finds quite a few with the same foot print.Looking at LTC4045 datasheet Vs STC4054..only a quick glance...looks pretty good to me as a drop in alternate. There are others as well....LR4054. Of course I reserve the right to be completely wrong here!https://au.mouser.com/ProductDetail/STMicroelectronics/STC4054GR?qs=%252BFmDY%2FmH7Ib7AgzA73nDoQ%3D%3Dhttps://www.st.com/en/power-management/stc4054.html#documentationlink below downloads a pdf ...sorry best I could dohttps://www.google.com.au/url?sa=t&rct=j&q=&esrc=s&source=web&cd=&cad=rja&uact=8&ved=2ahUKEwjBoYPkwOfzAhVNcCsKHXFvBr0QFnoECAIQAQ&url=http%3A%2F%2Fwww.lrc.cn%2FUpload%2FPDF%2FProduct%2FIC%2FLIB%2FLR4054.pdf&usg=AOvVaw2YbqgKqHWfz1pmum-UUchkcheers
Will Ferroxcuble EFD12/6/3.5 SMD  former always be in stock? - Page 1
Forum section: electronics / projects

author: ocset
author_rank: Super Contributor
timestamp: August 09, 2017, 07:54:03 pm
content: Hello,We need to design a single stage PFC’d Offline Buckboost converter LED driver for 30 to 100W. (as much power as components can be fitted inside the small enclosure that we have to work with)The enclosure that we must fit inside is 140mm x 65mm and just 8mm high. We are only allowed surface mount components inside this enclosure.We can put the AC filter and MOV, fuse etc, outside of this enclosure. Also, the bulk output capacitance, we have been told, can also be outside of this enclosure.We need a small isolated flyback bias SMPS inside the enclosure, but the smallest off-the-shelf core and former that I can find in surface mount is the EFD12/6/3.5 by Ferroxcube. (it must be <8mm in height)Since this is the only vendor of such a part in the world, can we always be sure that it would be in stock?Ferroxcube EFD 12/6/3.5 Core and SMD former:http://c1170156.r56.cf3.rackcdn.com/UK_PMA_EFD12_6_3.5-3C94_DS.pdf

author: leblanc
author_rank: Regular Contributor
timestamp: August 09, 2017, 08:08:09 pm
content: Given the note in the front page of the datasheet "Supersedes data of September 2004", I'd say these parts have been around for long enough to be at a pretty low risk of going obsolete any time soon. I sort of remember the part numbers, I must have used these a few years ago.Worst case scenario, you can definitely either find some Chinese knockoff (or a Chinese manufacturer that can make custom parts), potentially for cheaper. Or if you see it go NRND, just buy enough to last until the next product design iteration.

author: floobydust
author_rank: Super Contributor
timestamp: August 09, 2017, 08:37:24 pm
content: Ferrite cores have terrible lead-times, much worse than semiconductors.It's the core-gap that makes the part even harder to find in stock. Definitely find a second-source core, the bobbin can be a standard size and easier to procure.But will it always be in stock? I say dream on unless you volumes are high enough.For a standby-SMPS I would not make a transformer- it's cheap but don't forget regulatory approvals apply with the safety aspect.Your manufacturing know how to wind/insulate/varnish appropriately or expect surprises.I pick the SMPS IC and order an off-the-shelf transformer, fromCoilcraft,Wurthetc. Epcos/TDK offer this.If I need oddball windings, I get them to do it.If I have no room, I change/make the enclosure bigger because this is already silly to have one component in the world suitable for a product. Unless you can afford to stock them yourselves.
Will increasing the capacitance make it work without power - Page 1
Forum section: electronics / projects

author: Grayfox
author_rank: Regular Contributor
timestamp: April 30, 2014, 08:43:22 am
content: I have a jaycar flexi/interval timer which is based on a PIC16F84A and i want to use this to stop a my car from beeping non stop when i am cleaning it.The car beeps cause i have the keys in ignition while the drivers door is open.Now I could not leave the keys in the car but i like to listen to the radio while i detail the inside.I can tap the internal fusebox to get power during ignition so the device can reset when power is reapplied.Would replacing the 470uF and 100nF capacitors help keep charge for about 20seconds so it does beep for a short time.Power consumption according to silicon chip online.<50mA when relay is on<5mA when relay is offRelay status indicated via a red LED.Thank you

author: amyk
author_rank: Super Contributor
timestamp: April 30, 2014, 09:50:57 am
content: Did the thought of just disabling the door switch temporarily come to mind?The ones on my car even have a feature for this - push the button in and turn it clockwise to lock it in position. Turn it counterclockwise and it pops back out.

author: Grayfox
author_rank: Regular Contributor
timestamp: April 30, 2014, 10:58:43 am
content: I can remove the door switch easily but i do not want to do that as i still want warnings if the door is not closed when driving or if i leave the parking lights on.There is no option to turn this off.

author: Grayfox
author_rank: Regular Contributor
timestamp: May 01, 2014, 07:17:04 am
content: Been playing around with electrodroid and this set up my work just need someone who is more clued in about this sort of thing if this would do what i need.RC constant would be around 12sR is 12KohmC is 1mFV is 14+14v from ignition source---->|(diode)--------||(1mF cap)---~~~~~(12KOhm Resistor)------DC input to timer_____________________________________|__________________________________|Ground