hybridfree/eevblog-posts huggingface dataset:
Project outputs from Altium Designer - Page 1
Forum section: electronics / beginners

author: SlySmurf
author_rank: Newbie
timestamp: April 01, 2014, 01:23:57 pm
content: Hi all,Im not really into electronics per say as you guys probably are but part of my role is to learn Altium Designer. What Im trying to do is output a BOM from Altium which pulls the parts and their descriptions across - this will output to a xlsx file.When I select the output I can see the different fields for the output and required fields are selected but when I go to output the file it misses a field. Is this controlled\managed from somewhere else in Altium? Or am I missing something quite obvious?Thanks

author: T3sl4co1l
author_rank: Super Contributor
timestamp: April 01, 2014, 01:55:55 pm
content: What do you mean it misses a field?Are you using a template file?Tim

author: pa2ees
author_rank: Contributor
timestamp: April 01, 2014, 02:22:41 pm
content: Try outputting to CSV instead of xlsx, and then open the file with a basic text editor (such as notepad or emacs) to verify that Micro$oft Excel is not doing something weird (ie. make sure the columns you expect to be there are there). Also, make sure that the column has the 'show' field checked, whether it's in the 'All Columns' or 'Grouped Columns'.- Erik

author: tszaboo
author_rank: Super Contributor
timestamp: April 01, 2014, 05:59:36 pm
content: Try using output job files. It is a special file describing how to generate the output uniform way. Unfortunately there are still sub-sub-sub menus, but it is somewhat better.TBH I dont understand the problem. Can you post pictures describing it please?

author: SlySmurf
author_rank: Newbie
timestamp: April 02, 2014, 02:22:25 pm
content: Thanks for the quick replies guy. The solution was to have description= and then the field name. When this is applied the description values are pulled down to Excel from Altium.

author: T3sl4co1l
author_rank: Super Contributor
timestamp: April 02, 2014, 05:31:58 pm
content: Speaking of Descriptions...If you're importing fields from the Supplier lookup, you'll often get a Description attribute, which is NOT the Description field of the component itself! In the Parameter Manager, you see the component fields (Designator, Comment, LibRef, Description, etc... all those fields that are a fixed part of the Component Properties dialog), then to the right, you see all the attributes of all the components. The attributes have a Name and a Value, and the Name can be anything, even if it's already in use (like Description). There is no way to differentiate these in the BOM dialog, which picks the component field first.Thus, normally when I do all that (add supplier data and link and stuff to component), I copy and paste the "description" (attribute) to the Description (component's field). And then it all shows up on the BOM correctly, assuming I've remembered them all.(Has this changed in AD14 at all? I haven't seen if there are better solutions yet.)Tim
Project - Page 1
Forum section: electronics / beginners

author: aqsanaz444657
author_rank: Newbie
timestamp: December 24, 2015, 08:15:07 am
content: I wanna be make sound controlled l.e.d ( min 8 LEDs) pplz any one send me a working schematic..Sent from my DROID RAZR HD using Tapatalk

author: v8dave
author_rank: Regular Contributor
timestamp: December 24, 2015, 08:20:15 am
content: http://bfy.tw/3QjhMerry Xmas.

author: Leestons
author_rank: Contributor
timestamp: December 24, 2015, 04:46:45 pm
content: I don't think you could have made any less effort with this thread.

author: Aodhan145
author_rank: Frequent Contributor
timestamp: December 24, 2015, 08:25:44 pm
content: This is quite easy. I built a cube with 80 leds and all the Leds going to the music. Google is your friend everybody has done this before there are a lot of resources. I found using ws2812 leds were the best as I could easily control the colours and I had the colour and position changing to the music.

author: Halford
author_rank: Contributor
timestamp: December 24, 2015, 08:37:35 pm
content: Quote from: v8dave on December 24, 2015, 08:20:15 amI love the link!!!! I did not know it was possible
Projector comparison: BENQ W1070, OPTOMA HD26, EPSON POWERLITE 3000 - Page 1
Forum section: electronics / beginners

author: TRAPTRAP
author_rank: Regular Contributor
timestamp: January 30, 2015, 02:37:55 am
content: I'm trying to compare three home theater video projectors to replace my old Panasonic 53WX52F, which a few of you might remember from my first topic, where I was having trouble with shifting the display/text area?https://www.eevblog.com/forum/beginners/need-help-with-panasonic-53wx52f-tv-display/msg513058/#msg513058Well, that issue won't exist with a wall size projector! The text will be plenty big enough then!As listed in the title, I'm comparing a BENQ W1070, OPTOMA HD26, and an EPSON POWERLITE 3000?Pretty much, I'm looking for whoever has the...Biggest display (Which I think is the BENQ?)Best daytime watchingClearest picture (For text, and so on)I was the thinking the BENQ from what I've read between the three, but I was looking for more opinions first! Price range are in the same area, so I wasn't too worried on that.I plan to get whichever one falls the most rounded into the three categories? So, anyone who has these systems, or have seen them working, or who'd simply just like to help, FEEL FREE!
Promac Model 2A MOS Device Programmer - Software ??? - Page 1
Forum section: electronics / beginners

author: nh90wxr
author_rank: Newbie
timestamp: April 03, 2024, 05:19:26 pm
content: Hi folks,today I became a proud owner of above device, which works nicely for my first tries. Now am I looking for a bunch of SW for this device, capable of operating remotely via serial or parallel ports, which are present in hardware. This device is in general a stand-alone programmer with very nice features and a wide area of chips to check, program, read, verify, etc., but a remote operation is a thing I do dream of now.Is here in this forum someone able to guide me to an old or new source where the remote SW for this beast can be obtained? I appreciate all infos which may lead me a step further. Thank you in advance.Best regards.nh90wxr

author: nh90wxr
author_rank: Newbie
timestamp: April 05, 2024, 04:11:06 pm
content: Hi folks,in a German users manual (company was named SYNATRON GmbH in the eigties) I've found the information, that a remote software package for DOS was named PSH.EXE (general call to sub-parts) as remote executive, with sub-parts P2ACOM.EXE, P2CONT.EXE, P2EDIT.EXE and COMMAND.COM. I hope that these pieces of SW can be found somewhere by someone.Can someone help to identify and obtain these parts?Best regards.nh90wxrP.S. An english USERS MANUAL can be found here:https://archive.org/details/universal-mos-device-programmer-model-2-a-users-manual-promac/page/n7/mode/2up

author: m k
author_rank: Super Contributor
timestamp: April 06, 2024, 10:27:20 am
content: Connect the programmer using serial port and start a PC terminal program.Page 20/70 has cable examples.Xon/Xoff is supported soTx - RxRx - TxGND-GNDcable can be enough.Character format 19200,8,N,1 is pretty standard.Page 36/70 is Remote Control.If no software is available that is your only way.Page 38/70 has a send data example.There, after those few initial characters, you just pick the file with correct format and click send in terminal program.The programmer then send something back when ready.Raw binary file format is faster than any text based thing.

author: nh90wxr
author_rank: Newbie
timestamp: April 07, 2024, 07:58:01 pm
content: Hi folks,today after experimenting I managed to upload and download data via RS232 connection (FTDI sub-d 9-pol -> sub-d 9-pol -> sub-d 25-pol, selector switch on TTL) from my LINUX box to subject programmer. Downloading is accomplished simply by e.g. 'cat mouse.hex > /dev/ttyUSB0'. Minicom, Kermit, PuTTY or any other terminal programme can also be used in both directions. It's a happy day today for me...Best regards.nh90wxr

author: nh90wxr
author_rank: Newbie
timestamp: May 08, 2024, 09:20:43 am
content: To dig deeper into the details of this programmer I made two simple test jigs for testing the device according to test step 17 and test step 18. See attached picture for more details.
Propagation delay short? - Page 1
Forum section: electronics / beginners

author: zappedy
author_rank: Regular Contributor
timestamp: June 07, 2015, 12:36:18 pm
content: I want to read a 16 bit value over an 8 bit bus, so I'm using 2x 374 latches, and alternating which one has output enabled.If I select from only a clock signal + the same clock signal but inverted through a not gate, there will be a short interval, about one propagation delay long, where both latches are driving the bus.Is thereanyrisk that having both latches drive the bus simultaneously could fry something? Do I have to make sure only one output is enabled at any time?(It works in the simulator but I haven't wired it up yet because I'm going to have to order a PCB because the circuit grew large. I think the simulator I use, Logisim, mostly ignores analog details of circuits. I can't wrap my head around the different Spices unfortunately)

author: dom0
author_rank: Super Contributor
timestamp: June 07, 2015, 01:17:23 pm
content: Quote from: zappedy on June 07, 2015, 12:36:18 pmYou forget the propagation delay from output en/disable to the outputs of the latches. These are longer than the tpd of a inverter and are usually asymmetric by a couple ns (enabling outputs takes longer than disabling them).

author: Ian.M
author_rank: Super Contributor
timestamp: June 07, 2015, 01:22:35 pm
content: Not good. You really want non-overlapping enable signals.The '374 OE pin is active low, so your best bet is to OR a delayed version of the enable signal with the original signal to add some deadtime at the leading edge of the low going pulse. Getting complimentary enable signals from a single squarewave is best done with two XOR gates so you can match the propagation delays.
Proper 4x4 Keypad Operating Behavior? - Page 1
Forum section: electronics / beginners

author: t1d
author_rank: Super Contributor
timestamp: September 18, 2018, 10:20:16 am
content: I have these two keypads. They have what I consider to be an odd behavior. For both units, when tested with a DMM, some buttons will test correctly, for continuity. Other buttons do not, but they do register resistance, meaning something is getting through.I think the button switch contacts are some type of soft pad, which closes the circuit, on the bare traces, on the PCB.So, should they all register continuity, as I would expect? Or, due to the nature of the contact pad, resistance is typical. If resistance is typical, how is this type keypad employed in a circuit, generally speaking?https://www.ebay.com/itm/16-4x4-Buttons-Keyboard-Keypad-Key-Matrix-PIC-AVR-Stamp/370528911434?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2057872.m2748.l2649https://www.ebay.com/itm/4-x-4-Matrix-Array-16-Keys-4-4-Switch-Keypad-Keyboard-Module/150655776761?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2057872.m2748.l2649

author: Benta
author_rank: Super Contributor
timestamp: September 18, 2018, 11:52:08 am
content: Those keyboards usually have little rubber "nipples" under the keys. On the underside there is a soft conductive plastic part that closes the connection directly on the PCB.Conductive plastic has a certain resistance, so it's not like a metal to metal connection.Keyboard decoding is not an issue, there's no reason for low resistance.

author: PTR_1275
author_rank: Frequent Contributor
timestamp: September 18, 2018, 11:52:35 am
content: I’d say they might be borderline to what your meter counts as continuity or not. What is the resistance of them?

author: Richard Crowley
author_rank: Super Contributor
timestamp: September 18, 2018, 12:13:17 pm
content: That is normal. Because those switches use conductive rubber/plastic buttons you will never see the very low resistance of a traditional metal-to-metal switch.That kind of switch is typically used with a micro-controller to decode which switch is activated. Because very low voltage and current is used, a hard metal-to-metal, low-resistance contact is not required.Because the bottom part of those switches are a conventional PC board, and the top (plastic button) part is pretty standardized, it is relatively inexpensive to make very customized configurations for user interfaces for everything from automobiles to toys.

author: Rerouter
author_rank: Super Contributor
timestamp: September 18, 2018, 12:24:16 pm
content: It also comes down to the exact type of button, some will use metal pop domes, those are a hard short, but they cost more so they are rarely used (I like the feedback so Always pick them for my stuff) the rubber press pads generally seem to be about 100-1K resistance, they are generally graphite embedded or similar, so they make a conductor, just not a good one.

author: t1d
author_rank: Super Contributor
timestamp: September 18, 2018, 01:04:30 pm
content: The resistance was very low, AIR...All very great answers. Thanks, to each of you!
Proper balancing multi-cell Li* BMS - Page 1
Forum section: electronics / beginners

author: paulca
author_rank: Super Contributor
timestamp: December 31, 2017, 04:13:01 pm
content: Has anyone found a working BMS that supports multi-cell balance charging of Lithium Ion/Polymer, protection and charge/discharge control with inline load?It seems very difficult to find something that works and most of the current BMSs either work only for single cells or don't balance charge.

author: Nusa
author_rank: Super Contributor
timestamp: December 31, 2017, 10:55:00 pm
content: Or? I'd suggest that single-cell BMS's don't balance charge either. There's nothing to balance.

author: paulca
author_rank: Super Contributor
timestamp: December 31, 2017, 11:14:03 pm
content: Quote from: Nusa on December 31, 2017, 10:55:00 pmWell yes obviously. Are you suggesting limiting everything to single cell and parallel cells at 3.7V and using single cell BMS boards? Seem a bit limited. If you need roughly 12V using a 3.7V and boost converter doesn't sound efficient.

author: jonroger
author_rank: Regular Contributor
timestamp: February 25, 2019, 03:21:30 pm
content: I'm going to try this one. The IC used has 70mA of internal balancing. Fully open, with source code for the atmel CPU.https://www.tindie.com/products/ceech/18v-20a-lipo-li-ion-battery-management-system-bms/
Proper Interpretation of Clock Accuracy Spec. - Page 1
Forum section: electronics / beginners

author: frostheave
author_rank: Contributor
timestamp: May 05, 2015, 03:07:37 pm
content: I am trying to figure out the accuracy of the clock with the following specs:Arduino Accurate Clock ShieldClock uses the DS3231 IC from MaximStandardized and stackable shield board compatible with the Arduino I/O Pins. Uses the Tx & Rx pins on the controller. Uses I2Cfor host communications <25MHz.Power: 3-5VDC/ 200uA active, 900nA(timekeep)Accuracy: 2ppm 0C-40C (~1min/Yr)L: 2-5/16” W: 1-13/16” WT: .04The stated accuracy is 2ppm. Here are my calcs:* 60 sec/min x 60 min/hr x 24 hr/day x 365 days/yr = 31,536,000 sec/yr* 31,536,000 sec/yr / 2,000,000 = 15.768 sec/yrSo, if my math is correct, does this mean the clock is accurate to +- 15.768 sec/yr ?Thanks for your help!

author: jolshefsky
author_rank: Regular Contributor
timestamp: May 05, 2015, 03:49:45 pm
content: Quote from: frostheave on May 05, 2015, 03:07:37 pmI think it's 31,536,000 sec/yr * 2 parts/1E6 = 63 sec/yr = ~1min/yrAs for whether that's the correct way of interpreting the data ... I don't know either.

author: frostheave
author_rank: Contributor
timestamp: May 05, 2015, 03:58:27 pm
content: Quote from: jolshefsky on May 05, 2015, 03:49:45 pmAh, thank-you jolshefsky. That makes more sense and it matches the given quote. I suppose that means+ or - 63 seconds per year?

author: Rick Law
author_rank: Super Contributor
timestamp: May 06, 2015, 12:34:24 am
content: + or - up to 63 seconds.Up to 63 seconds means any numbers <= that 63 magic number. So it could be off just 1 second, 10 seconds, 62 seconds, or any number from 0-63 seconds.

author: frostheave
author_rank: Contributor
timestamp: May 06, 2015, 01:56:47 am
content: Quote from: Rick Law on May 06, 2015, 12:34:24 amExcellent. Thank-you Rick.
Proper method to clean soldering iron barrel and nut - Page 1
Forum section: electronics / beginners

author: Hogwild
author_rank: Regular Contributor
timestamp: November 26, 2017, 04:19:18 am
content: Hi everyone:I am putting in a new tip in my Weller WP25. Since the barrel and nut of the iron are really oxidized and have some of that white residuepowder on them, I'm wondering...what is the proper method to clean the barrel and nut.Almost every soldering post and video on the web talks about tip maintenance, but makes no mention of how to clean the barrel andnut.Thanks in advance.

author: Alex Eisenhut
author_rank: Super Contributor
timestamp: November 26, 2017, 05:54:48 am
content: I don't know. I got a tube of this years ago and I used it on all threads.https://www.tequipment.net/Hakko481-026.htmlNothing seizes anymore.

author: stj
author_rank: Super Contributor
timestamp: November 26, 2017, 05:55:57 am
content: IPA and a wire brush.
Proper MOSFET Bench Test - Page 1
Forum section: electronics / beginners

author: OpenCircuit
author_rank: Regular Contributor
timestamp: March 21, 2017, 08:30:31 pm
content: Wanted to make sure I have a properly planned test for these MOSFETs (6R190E6 HBG203) and will not destroy them:https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=1&ved=0ahUKEwifo6-gtujSAhWn5oMKHcfeBbEQFggcMAA&url=http%3A%2F%2Fwww.infineon.com%2Fdgdl%2FInfineon-IPA60R190E6-DS-v02_03-EN.pdf%3FfileId%3Ddb3a3043284aacd801286c9f28472921&usg=AFQjCNEOY_79BghqVkPc6MYAFdzytsaGCg&sig2=mRTJqW_AAUJ8JjvVf4KUvg&cad=rjaPlan:?

author: w2aew
author_rank: Super Contributor
timestamp: March 21, 2017, 08:36:53 pm
content: Not quite. You should connect the fan between the positive power supply pin and the Drain. Connect the Source to the Ground. Also, include a resistor (value not critical, say 10K or so) between the Gate and Source so that the gate capacitance will discharge when you remove the 3.3V. Finally, add a reverse biased diode (1N4001 etc.) across the fan to prevent inductive kickback from stressing the FET when you turn the fan off. Note that 3.3V won't be enough to fully turn on this device according the datasheet. See the curves on page 10 and later. If it is a very low power fan, it might be sufficient...

author: danadak
author_rank: Super Contributor
timestamp: March 21, 2017, 09:27:05 pm
content: Without knowing the fan electrical specs or the switch usedto turn on the MOSFET (thinking bounce issues) or the frequencyof swicth cycling I would recommend you bolt the MOSFET to aheat sink just in case it spends a extended period of time in thelinear area dissipating power and heating up.Regards, Dana.

author: OpenCircuit
author_rank: Regular Contributor
timestamp: March 21, 2017, 09:44:34 pm
content: Excellent, thanks for the help!Dana, thanks for posting. Both FETS are mounted to an aluminum plate. removed this from an ATX switching power supply I am trying to fix:https://www.eevblog.com/forum/repair/atx-power-supply-dead/

author: OpenCircuit
author_rank: Regular Contributor
timestamp: March 21, 2017, 10:21:56 pm
content: You were correct; 3.3v was not enough to power the fan on completely. I did try 5v at the gate and it did turn the fan on completely. Was sure hoping they were bad so I could say problem likely solved. Oh well, at least I reached a conclusion.
Proper Position of Smoothing Cap and Why? Solved - Page 1
Forum section: electronics / beginners

author: t1d
author_rank: Super Contributor
timestamp: May 21, 2024, 05:40:59 am
content: (Assuming the proper small value caps are installed on the Voltage Regulator...) Which is the correct, or better, placement for the Smoothing Cap and why?1) Mains to Transformer to Bridge Rectifier to Smoothing Cap To Voltage Regulator To Load.Or2) Mains to Transformer to Bridge Rectifier To Voltage Regulator to Smoothing Cap To Load.My guess is #2, because that allows the Smoothing Cap to support the Voltage Regulator, as well.I look forward to your answers. Thank you for your help. Cheers!

author: Swainster
author_rank: Frequent Contributor
timestamp: May 21, 2024, 07:48:40 am
content: TLDR: why not both?Assuming that you are talking about a linear regulator, then one way to look at the situation is to ask these questions;1) Can a linear regulator do its job when the input is below the require out voltage (plus drop-out voltage)?2) What does the "un-smoothed" output of a bridge rectifier look like?These 2 questions lead to #1 being the unavoidable choice, at least for smaller devices. Larger loads may require power factor correction in order to comply with local regulations, which may muddy the waters.That said, if your design has some kind of particularly 'pulse-like' load, then you would do well to put some local bypassing nearby to that load.In other words, your #1 option is the usually the best choice, but often there is an element of #2 as well.

author: t1d
author_rank: Super Contributor
timestamp: May 21, 2024, 09:54:23 am
content: Quote from: Swainster on May 21, 2024, 07:48:40 amThanks, Swainster! That's a great answer, information and thinking. Much appreciated!
Proper voltage/current- N Channell Mosfet - How to understand data sheet? - Page 1
Forum section: electronics / beginners

author: b9creations
author_rank: Contributor
timestamp: August 30, 2016, 01:10:26 am
content: Hello,Am setting up a simple flyback circuit using this mosfet:http://www.mouser.com/ds/2/196/irfp044npbf-937753.pdfHave looked over the data sheet many times but unable to understand how to interpret the info I need.My question: how much current/voltage is needed to supply the gate of this Mosfet?Will 3 or 4uA (milliamps) and 233uV (millivolts) be enough to drive this baby? (That's what the sim shows)Is there an optimal ballpark figure for the TO247 package?Thanks very much for any help, would really love to learn how understand the data sheet for future reference.Best regards to you

author: Ammar
author_rank: Regular Contributor
timestamp: August 30, 2016, 01:21:23 am
content: It depends how fast you want to switch. The gate capacitance is 1.5nF so switching on and off is very much like charging and discharging a 1.5nF capacitor. Use RC time constants to figure out how long it will take to get the gate-source voltage to the level you want. Figure one shows you how much drain current the device can pull based on the gate-source voltage.I hope that helps!

author: b9creations
author_rank: Contributor
timestamp: August 30, 2016, 01:43:43 am
content: Yes, thanks Ammar, I will check that out.I guess it's more complicated than my electronics knowledge allows.One of the circuits it's 1nF and the other uses 20nF. I guess I will just try it out on the breadboard and see what happens! lol kaboom!It seems to work in the everycircuit simulator so I guess I will find out. BTW, what a great app! So much fun to use.

author: Ian.M
author_rank: Super Contributor
timestamp: August 30, 2016, 02:06:30 am
content: If you switch it too slow (by not supplying enough gate current), and there is a significant voltage on the drain, with enough current available, it goes *BANG*. That's whatFig 8. Maximum Safe Operating Areais about. However Fig 8 assumes its case temperature is held at 25 deg C, and if you switch it more often it will heat up and you will have to derate.To get it to switch in 10ns, you need to slam at least 60mA into the gate, and to get its rated Rds_on you need to drive the gate to +10V relative to the source.Also you seem to have some confusion. uA is microamps, uV is microvolts, both one millionth part of their base unit. You are mixing them up with mA : milliamps and mV : millivolts.(ignoring the common forum use of u for greek µ)Even if you have 4mA available, 233mV is grossly insufficient voltage to even start turning it on.

author: b9creations
author_rank: Contributor
timestamp: August 30, 2016, 02:13:33 am
content: Yes that is helpful thanks again.Now I know where to measure the voltage, from the Gate to the Source, so it's a little over 10V and I was measuring in the wrong place. : )

author: T3sl4co1l
author_rank: Super Contributor
timestamp: August 30, 2016, 06:03:33 am
content: Uh yeh...WHAT, exactly,was your simulation saying?Because if it was DC, that's not what's important to the gate capacitance!Tim
Proper way of triggering LED - Page 1
Forum section: electronics / beginners

author: elki
author_rank: Regular Contributor
timestamp: April 10, 2024, 03:08:28 pm
content: A very basic question. Naively, the circuit attached should be the most straightforward way to trigger a LED by a TTL-like pulse to the base of a NPN transistor. Somehow, when tested in real life, the input triggering pulse becomes distorted, which looks like a parasitic capacitance effect. Is there any way to secure the input signal shape when pulsing the LED?

author: jmelson
author_rank: Super Contributor
timestamp: April 10, 2024, 03:54:14 pm
content: Your R1 (10K) only allows about 0.3 mA to flow through the LED. Your base resistor R2 (1K) allows at least 3 mA of base current. R2 should be at least 20 X larger resistance than R1.Jon

author: edavid
author_rank: Super Contributor
timestamp: April 10, 2024, 04:06:11 pm
content: You don't say exactly what problem you are seeing.The saturated NPN switch will be slow to turn off - is that it?For a visual indicator, this doesn't matter and your circuit is fine.If you are trying to generate fast pulses, a different circuit would be better. In that case, what are your actual speed and current requirements?When you say it was tested in real life, did you build it, or just simulate it?

author: Peabody
author_rank: Super Contributor
timestamp: April 10, 2024, 04:16:32 pm
content: Yes, it looks like the resistors need to be switched.Also, any distortion in the base drive could also be dependent on the output capabilities of the "In" drive source, which become more important with such a low base resistance.Could you draw us a picture of what you're seeing?

author: kevin.gibbs
author_rank: Regular Contributor
timestamp: April 11, 2024, 02:20:17 pm
content: Where are you measuring the distorted signal, and what is the duration of your pulses? Can you share the actual waveform?
Proper way to bias a hot wire barretter - Page 1
Forum section: electronics / beginners

author: mazurov
author_rank: Frequent Contributor
timestamp: July 30, 2015, 01:59:48 am
content: I recently scored Weinschel M926 barretter (see picture), seemingly in good working order. The LF output shows 150-ish ohms which sounds right. The bias is specified at 4.5 mA on the case.I don't quite remember how to use this thing. Shall I get a bias tee on LF out? I'm looking at old books and it seems ppl used batteries to bias barretters when they were hot. Also, my supply only steps in 1 mA steps, do I need to worry about 0.5 mA difference?
Proper way to shut down RPi2 + vncViewer - Page 1
Forum section: electronics / beginners

author: Vindhyachal.takniki
author_rank: Frequent Contributor
timestamp: June 27, 2015, 08:09:57 am
content: 1. I have installed vnc-server on RPi2 board & vncViewer on laptop PC.2. Now I have been able to run RPi2 via laptop PC.3. I want to know what is the correct way to shut down RPi2 board via laptop.4. If I directly close vncViewer on laptop, a messsgae is displayed that "connection is graciously disconnected" & screen is gone.I don't know that at this point if Pi board is shut or running?

author: electr_peter
author_rank: Unknown
timestamp: June 27, 2015, 12:25:44 pm
content: To be sure that RPi is shut down, open terminal program and type:Code:sudo shutdown -h nowCommand will close all programs and communications, RPi will shutdown and your PC will say something like "connection is lost".This command can be automated via scripts, links, etc.

author: Muxr
author_rank: Super Contributor
timestamp: June 27, 2015, 03:55:56 pm
content: you can also use:Code:haltand for reboot:Code:rebootYou have to have root privileges to do it. So if you're not logged in as root you would generally use "sudo" (superuser do) to execute the command. Example:Code:sudo halt

author: PA0PBZ
author_rank: Super Contributor
timestamp: June 27, 2015, 05:27:41 pm
content: Quote from: Vindhyachal.takniki on June 27, 2015, 08:09:57 amThe board is still running, which you can verify by trying to reconnect.

author: eejake52
author_rank: Contributor
timestamp: June 28, 2015, 02:42:33 pm
content: If you are running the graphical interface on the Pi (which would be the only reason to use vncViewer), then click on the raspberry menu and select "Shutdown". Otherwise use any of the command line methods mentioned above.
Proper Way To Use An Oscope On Grounded Battery Bank - Page 1
Forum section: electronics / beginners

author: frostheave
author_rank: Contributor
timestamp: December 11, 2014, 07:58:04 pm
content: Hi All, I am very much a noob when it comes to using an oscope and am looking to learn. A recent post about measuring high current DC got me wondering about the following hypothetical question.Say we have a small -48Vdc battery plant and want to measure the voltage of the plant with a scope. The battery charger, scope, and battery plant are all connected to Earth Ground, as seen in the picture below. What is the Proper and Safe way to perform the measurement?Thank-you for your help.

author: tautech
author_rank: Super Contributor
timestamp: December 11, 2014, 11:32:48 pm
content: Your diagram looks correct.When in doubt check with a DMM for voltage from where you wish to clip the reference lead (Gnd) to Scope BNC's (mains Gnd)If they are connected(common) there is often no need to attach the reference lead for simple measurements.

author: frostheave
author_rank: Contributor
timestamp: December 13, 2014, 02:51:16 am
content: Good deal. Thanks tautech.
Proper wire guage for USB-C GBA-SP - Page 1
Forum section: electronics / beginners

author: pharaoh3
author_rank: Contributor
timestamp: June 14, 2024, 04:36:51 pm
content: A buddy purchased a modded GBA SP from a pawn shop, and he asked me to work on it. The GBA SP had a USB-C installed whose wires were too thick and bridge a connection to the original charging port. I want to use a wire of this gauge so that I can solder them in to the circuit board. Would the wire below be suitable?Link to USB-C:https://www.boxypixel.com/collections/game-boy-advance-sp/products/type-c-battery-charging-board-with-protectionLink to wire:https://amazon.com/dp/B01M70EDCW

author: dferyance
author_rank: Regular Contributor
timestamp: June 14, 2024, 07:42:29 pm
content: Hard to say exactly but I'd go with something a little thicker than 30 AWG. That's pretty thin and can easily break. It might be fine but it wouldn't be my first choice, I'd go with 28 or 26. Careful with stranded wire as it is easy to miss a strand and have it short something else out. It sounds like you are soldering to a small connector, solid wire would be easier if you can use it.
Properbly calibrate cheap Ebay Volt/Ammeter - Page 1
Forum section: electronics / beginners

author: tobimai
author_rank: Newbie
timestamp: November 12, 2016, 09:21:26 pm
content: Hello,I bought a cheap (8€) dual Volt/Amp meter on Ebay from China. If a adjust the pot on the back so that it shows 2V if it's supposed to show 2V. But If I then apply 12V it shows only 11V for example. Is there any way to properly calibrate it or is it just "Chinese accuracy"ThanksTobi

author: Kleinstein
author_rank: Super Contributor
timestamp: November 12, 2016, 09:27:19 pm
content: Usually there is just one adjustment for the scale factor. So looks like this unit has a problem - if 12 V is near the maximum, this could be a protection circuit.
Properly mounting foot mount transformers - Page 1
Forum section: electronics / beginners

author: queennikki1972
author_rank: Regular Contributor
timestamp: May 10, 2019, 03:13:46 am
content: I know, more dumb questions, Im happy I found all of you.On my first little power supply i had used such a small transformer I mounted it directly on a raised circuit board with nylon stand offs, so it was in no way touching the enclosure. However, my question is, when mounting larger (Foot Mount) type transformers, can the foot be mounted directly to the bottom of the metal enclosure or does it needed to be suspended above the metal enclosure to prevent any contact?

author: ataradov
author_rank: Super Contributor
timestamp: May 10, 2019, 03:34:21 am
content: It depends on the transformer design. Typically large transformers like that have a plastic spool on which the wire is wound. That spool provides plenty of isolation.But if it is a cheaper version, it might have just a thin insulating wire between the core and the winding. In that case I would err on the safe side and not expose the transformer to the user in any way.

author: queennikki1972
author_rank: Regular Contributor
timestamp: May 10, 2019, 03:41:36 am
content: Here is the types I mean. Seems to have plastic in the center

author: ataradov
author_rank: Super Contributor
timestamp: May 10, 2019, 03:44:15 am
content: Just mount to the chassis, don't worry about it.The core is not electrically connected and it does not care if it is connected to the earth (as hopefully your case is).The only concern is if the insulation fails, but in this case insulation is provided by that while plastic, and that's enough plastic.

author: T3sl4co1l
author_rank: Super Contributor
timestamp: May 10, 2019, 04:18:15 am
content: Indeed, the core should be grounded in case of failure of that plastic layer: that way fault current flows to GND, away from possible touch.Tim

author: Brumby
author_rank: Unknown
timestamp: May 10, 2019, 10:59:13 am
content: If mounting to a metal panel, then just bolt it straight on.But if you're going to mount one in a plastic case, then I would suggest mounting it to a metal plate that has a larger footprint and mount that plate to the plastic. The reasoning is that if something happens and the transformer overheats, then by having it on a larger plate, the plate will slow the passage of heat to the plastic which is holding it in place. An overheating transformer directly mounted to a plastic case could melt it's way to freedom ... and chaos.

author: TERRA Operative
author_rank: Super Contributor
timestamp: May 10, 2019, 11:19:37 am
content: I bolt them straight down to the chassis then run the earthing wire from one of the mounting bolts to the earth lug on the power connector.That way I know it it well earthed right where the mains voltage is and I don't have to drill another hole, and I save a bolt and nut too.
Proportional Directional Valve Controller PCB - Page 1
Forum section: electronics / beginners

author: jamesta
author_rank: Newbie
timestamp: May 07, 2013, 03:45:23 pm
content: Hello everyone,This is my first topic in EEVblog. Please help me to trace out an electronics fault in a valve PCB I am testing. The PCB is for sending a proportional PWM signal to the valve coils. The fault is that sometimes the controller works and sometimes it does not and I want to find out what is causing it. I don't have a schematic of the circuit, but only a block diagram and I can list out the components if anyone can help me.Please advise how to proceed from here.

author: somlioy
author_rank: Regular Contributor
timestamp: May 07, 2013, 04:22:43 pm
content: Post more info please. It sounds like a bad connection somewhere tho.

author: SeanB
author_rank: Super Contributor
timestamp: May 07, 2013, 05:52:37 pm
content: Look for broken traces, dry joints ( especially on connectors and heavy components and ones that run hot) along with dying capacitors. Photos can help a lot, good quality high resolution ones on a site like Flickr ( post the small thumbnails here so the highres ones can be clicked through to) of front and back of board, along with the block diagram.
Pros and cons of planar transformers - Page 1
Forum section: electronics / beginners

author: romovs
author_rank: Contributor
timestamp: July 07, 2013, 04:09:47 am
content: I was looking for some low profile transformers and stumbled upon planars.Surprisingly there is next to none information about them on the internet (or perhaps it's just me failing at googling).Judging by the datasheets they seem to be: lower profile than toroids, higher price, higher efficiency at higher frequencies.What about disadvantages? Are there any situations when planars should be avoided?

author: SeanB
author_rank: Super Contributor
timestamp: July 07, 2013, 05:29:14 am
content: Cost for one, they are only going to be used when you have no other choice as you need the reduced height and the current is high. Otherwise a plain ferrite core will be better. Often I have seen a standard low profile transformer mounted in a routed hole in the board and connected via the mounting pins to the pads or via short ends of the windings to get the extra 5mm of height reduction so as not to go planar. The planar are a lot wider as well, so take up more board space.

author: WarSim
author_rank: Frequent Contributor
timestamp: July 07, 2013, 06:36:20 am
content: Planar transformers all started with the notion of cost and space savings.Simple transformers turned out to be too inefficient.Then more magnetic principles were introduced but these dramatically increased production costs.There has be several such evolutions and papers on the subject.Over the years new understandings and realizations of limitations have been discovered.The original intent was to give the option for engineers to intrinsically include planar transformers in their projects. Unfortunately the physics involved in creating efficient planar transformers proved to be beyond most electronics engineers.Next was the idea to sell pre-designed planar transformers that still offered some of the space saving advantages without requiring magnetic design theory.What you can buy today is what the manufactures can produce for what they believe engineers will pay for the space saving benefits.So what you can buy is a compromise of the intent of planar, manufacturing process, and efficiency.There have been allot more efficient and allot more expensive to create planar transformers made.This is not the end of the planar transformer it is still maturing.If you decided to used a planar transformer please read the datasheet carefully. The selected manufacturing process may have surprising limitations normally assume with conventional transformers.
Pro'sKit SS-331 H and non-H difference - Page 1
Forum section: electronics / beginners

author: josip
author_rank: Regular Contributor
timestamp: September 06, 2024, 09:43:08 am
content: What is difference between Pro'sKit SS-331 and Pro'sKit SS-331H?EDIT: I found that is marked on the box, it is related only to supply voltage?

author: ledtester
author_rank: Super Contributor
timestamp: September 06, 2024, 10:45:58 am
content: Regarding the differences between the versions, on this page:https://www.amazon.com/2019-New-SS-331H-220V-Desoldering/dp/B082MDQY5NI found this:
Protect circuit from accidental application of power to A/V out port. - Page 1
Forum section: electronics / beginners

author: ruthsarian
author_rank: Contributor
timestamp: February 28, 2017, 04:26:13 pm
content: I have an old video game console that outputs an RF video signal. My plan is modify the console to output composite video and audio so I can connect it to a device that doesn't have an analog tuner in it. My thought was to use a 3 or 4 conductor 1/8" phone jack (audio is mono so I don't necessarily need separate left/right audio lines) like you might find in some portable DVD players or camcorders.The problem is that this console, a 1975 Atari Pong, has a power plug (called the "battery eliminator" as it was normally powered by 4 D-cell batteries) which uses a 2 conductor 1/8" phone jack. I'd like to protect the circuit from someone plugging in that 1/8" power adapter into the A/V jack. How would I do that? It seems a few diodes would be in order, but I'm guessing the forward voltage of the diodes would degrade the video and audio signals. Would that be the case? And if I could use diodes for this, would I need something special, like a low forward voltage, high frequency diode? Or is there another way? Maybe PFETs?The simplest solution would be to not use the 1/8" jack for A/V and instead use RCA connectors. Maybe that's the way I'll go, but I'd still be interested to hear if there's a solution to using the 1/8" jack.Thanks

author: rstofer
author_rank: Super Contributor
timestamp: February 28, 2017, 05:30:22 pm
content: Composite signals ordinarily come out on RCA jacks and that solves the problem.It may turn out that there are blocking capacitors on the video and audio signals (I wouldn't be surprised since they probably want to remove any DC bias) and plugging the power supply plug into the video output socket may not cause any damage. I would want to know a lot more about the circuitry.Perhaps a 1/4" audio plug? Maybe a 5 pin DIN?If there is room, I would opt for the RCA jacks since that is a standard.

author: vk6zgo
author_rank: Super Contributor
timestamp: March 01, 2017, 01:48:34 am
content: 1/8" phone jacks are horrible,cheap,flimsy things at best, so I would recommend you steer well clear of them.I don't like RCA connectors that much, but at least you can buy sturdier versions of them, which are OK.Using the same type of connector for both power & A/V is asking for trouble, as is farting around with diodes on video & audio circuits.
protect IC from hot air - Page 1
Forum section: electronics / beginners

author: harps
author_rank: Regular Contributor
timestamp: May 17, 2014, 07:03:49 pm
content: helloI have to remove a unique ROM chip from a damaged HD and transplant it to another donor PCB.i have just bought the same hot air gun as Dave, an Atten 858d+, some kapton (temp resistant) tape for the surrounding parts and also some high quality no clean flux, in a pen, from RS components.Q: As the ROM chip is so valuable, could I place a small square piece of kapton tape on the IC itself so that when i heat the legs, i do not heat up the actual chip? or does it not work like that?thanks for help : )

author: Simon
author_rank: Unknown
timestamp: May 17, 2014, 07:14:55 pm
content: if you can put something on the chip body that does not conduct heat well it will help stop the chip from heating if hit with hot air from the gun

author: harps
author_rank: Regular Contributor
timestamp: May 17, 2014, 07:20:34 pm
content: Great , i shall cut a piece of kapton tape and stick it on the IC body to help protect it.I was not sure if the body of the ic needed to get hot too, as all the tutorials i have seen, no one has tried to keep the chip cool during removal.thanks.

author: Simon
author_rank: Unknown
timestamp: May 17, 2014, 07:23:51 pm
content: heating the body of the IC is not neccessary, it is the pins that need the heat, most surface mount stuff is rated for a certain high temperature for a few seconds once only to allow it to be soldered, as your re-using the part it could be touch and go.
Protecting 2 18650 Li-ion batteries. - Page 1
Forum section: electronics / beginners

author: VEGETA
author_rank: Super Contributor
timestamp: September 30, 2016, 09:07:09 am
content: HiI've been searching of means to protect 2 series 18650 batteries (assume unprotected and not genuine) and I came up with this:Instead of an IC to protect the 2 of them together, I thought of protecting each one of them individually using this IC:http://www.diodes.com/_files/datasheets/AP9211.pdfThis IC has the 2 mosfets inside it, so will it work this way? I tried to mimic the status of having 2 protected cells in series. Here is a schematic photo:What will happen if the user put 2 protected cells with this circuit?thanks

author: amyk
author_rank: Super Contributor
timestamp: September 30, 2016, 11:14:37 am
content: Yes, protected cells will work the same as normal cells within the protection limits. They may appear to have a slightly higher internal resistance due to the MOSFETs within the protection.

author: VEGETA
author_rank: Super Contributor
timestamp: September 30, 2016, 02:24:02 pm
content: So my circuit is correct if the 2 cells put in series?My concern is that the protection IC is made for one cell... so maybe the voltages will affect it. Like having 0-4v for first cell while the 2nd one is 4-8v. I wonder if this is normal and won't make a problem.The datasheet I guess says "Battery positive" and "Battery negative" so voltage doesn't matter here. My point is having a +4v voltage difference between VDD and VSS instead of a true 0v on VSS. Is this gonna work fine?

author: VEGETA
author_rank: Super Contributor
timestamp: October 06, 2016, 11:03:09 pm
content: Will my circuit work for non-protected cells? 2 in series?

author: VEGETA
author_rank: Super Contributor
timestamp: February 18, 2017, 07:01:14 pm
content: I've thought about this and I finally settled to use 4 Li-ion batteries! 2 in series and 2 in parallel for increased current because it is important for me. The pack's total voltage is 8.4v maximum, so will this individual protection technique works fine or should I make a 8.4v over-voltage protection for the whole pack?If protecting the whole pack is safe I will get it... but what IC? I couldn't find a suitable IC for this. I am glad to take help.
Protecting an H-bridge, from the unusual - Page 1
Forum section: electronics / beginners

author: mutas
author_rank: Newbie
timestamp: November 30, 2016, 02:43:23 am
content: Hi everybody,I'm a beginner, and am trying to solve somewhat of an unusual problem. The project involves protecting an H-bridge circuit that is used to drive a telephone bell ringing solenoid. The circuit that I am working with is essentially the one seen in the Sparkfun Port-o-rotary phone project, seen here; the "High Voltage Ringer" page:https://www.sparkfun.com/datasheets/Port-O-Rotary/Port-O-Rotary-v29-2.pdfFor my application, the solenoid also happens to be connected to a 5-bar magneto, that can produce 80+V AC. My goal is to use the Port-O-Rotary ringer circuit to drive the ringer solenoid of an old-time hand crank telephone. Somehow, I also want to maintain the original behavior of the telephone by allowing the bells to be rung by turning the hand crank magneto. Since the ringer solenoid must be driven by both the H-bridge, AND the hand crank, I am really stuck on what (if anything) must be done to protect the H-bridge (and by extension, the microprocessor which drives the H-bridge) from any voltage emitting from the hand-crank magneto.I would really appreciate any guidance or hints you folks might have.Thanks,_matt

author: jeroen79
author_rank: Frequent Contributor
timestamp: November 30, 2016, 01:32:35 pm
content: What current will the ringer draw?The microcontroller can be protected by isolating it with optocouplers.For the H bridge:-Use components that can withstand 80VAC.-Use a transformer to keep the voltage on the H bridge side low.-Use a relay to switch the ringer between the H bridge and the crank.

author: mutas
author_rank: Newbie
timestamp: December 01, 2016, 07:15:00 am
content: Hi, thanks for the reply and suggestions!The solenoid draws around 6mA at 30V.If I were to go with something like a SPDT relay to switch between either the magneto or H bridge, as the signal voltage for the solenoid, would that pretty much get the job done? Would I even need to worry about opto-isolation, or other forms of protection at that point?Thanks again!