hybridfree/eevblog-posts huggingface dataset:
RFID reader, missing proper docs, how to utilize Door Bell wires? - Page 1
Forum section: electronics / projects

author: nardev
author_rank: Unknown
timestamp: March 03, 2017, 12:24:03 pm
content: I bought some cheap RFID reader, which is not standalone , so i was thinking to make something with arduino.This is the reader i got:http://www.ebay.com/itm/322252348733?_trksid=p2057872.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AITI was able to establish data connection, to read cards and keyboard input, turn on/off buzzer and led, but i don't know how to utilize the Door Bell.I tried to read any voltage/analog/digital movements on those two wires but i didn't notice anything. As if those are dead.Seems to me as quite popular reader type, so many out there but no docs how it actually works.Issue with it is that there are two wires just labeled as "ring" or "Door Bell" and i don't know how to use them.Here is the only doc i have:https://www.soselectronic.cz/productdata/12/70/19/127019/RFID_CARD_R.pdfAnyone has any idea, what to do? What to try?Greetings.

author: jeroen79
author_rank: Frequent Contributor
timestamp: March 03, 2017, 01:06:34 pm
content: Maybe the wires are shorted when the 'bell' button is pressed?

author: nardev
author_rank: Unknown
timestamp: March 03, 2017, 05:30:32 pm
content: ha ha you were rightthank youthank you so muchomg, how dumb i was... i expected more of this thing
RFID scanner stopped suddenly - Page 1
Forum section: electronics / projects

author: Md Mubdiul Hasan
author_rank: Regular Contributor
timestamp: October 20, 2017, 01:51:56 am
content: Hello There,I need a suggestion how to proceed a hardware failure. Recently, I am working with a RFID scanner( 1D and 2D) that has a variety of application(Buzzer,vibrator,bluetooth senors) interfaced with android smartphone. This device has a Gun interface (similar tohttps://www.go4mobility.eu/wp-content/uploads/2017/06/M3-Mobile-RFID-Gun-Handleiding-User-Manual.pdf).When I frequently scan the object through RFID, the device gets power OFF suddenly after 1 hour test. For sure, PCB is also getting hot.I am not sure whether it has firmware or hardware problem.Kindly suggest me what to do, in case of power management IC, this has been used,http://www.ti.com/lit/ds/symlink/bq24074.pdf.Thank you
RFID/NFC bcb design - Page 1
Forum section: electronics / projects

author: mickpah
author_rank: Regular Contributor
timestamp: January 04, 2013, 09:38:18 pm
content: HI all,I'm playing with NFC and have been using an excellent breakout from microbuilder ->http://www.microbuilder.eu/Projects/PN532.aspx.I'm now to the stage where I want to move the breakout to an embedded board, however RF PCB design is something I have never dabbled in (waiting for someone to say 13 Mhz is DC) . I know I need to tune the antenna and a VNA is so far out budget as to be a dream.I have found this producthttp://www.microbuilder.eu/Projects/PN532.aspx& it looks interesting , but is it in the same category as the nano Oscilloscopes, little better than a toy ? My gut feeling is ad $350 product replacing a $14k tool is well into the too good to be true range on the Bulllshit-O-meterTM, but may just be good enough to help me get a PCB antenna working.Comments and guidance most welcome please.
RFM12/RFM69 Standby? - Page 1
Forum section: electronics / projects

author: NivagSwerdna
author_rank: Super Contributor
timestamp: September 01, 2016, 07:22:15 am
content: Does anyone have experience of using the RFM modules in very low power applications?I would like to have my module basically OFF for the majority of the time since I have a weigh scale application which will only weigh a few times per dayI am very new to design!My options seem to be...Put the RFM12 on the 3v3 power rail (Power rail will be around 3v3, intermittently pumped from cell voltage)Power the RFM12 from a PIC pinSwitch power to the RFM12 via a MOSFETAny recommendations?

author: EmmanuelFaure
author_rank: Regular Contributor
timestamp: September 01, 2016, 01:21:39 pm
content: https://lowpowerlab.com/forum/
RFSoC multiboard synchronization - Page 1
Forum section: electronics / projects

author: jhenderson0107
author_rank: Regular Contributor
timestamp: March 27, 2020, 04:48:42 pm
content: Here's a screenshot of my current project involving concurrent capture/playback from multiple Xilinx ZU39 RFSoC SOMs (system-on-module). Depicted are two 4x5" SOMs atop two carriers. Each card has sixteen, 6.4 GHz DACs and sixteen 2.2 GHz ADCs, all operating synchronously with other cards in the system. In this test, all ADCs from board A are connected to DACs from board B and vice-versa. In the application, each subsystem will incorporate sixteen such cards each operating from a common reference clock providing 256 coordinated DACs and ADCs. All analog I/O samples are aligned +/- 0 samples based on a common trigger, issued by an arbitrary card in the system designated as master.Petalinux is running on each RFSoC and all cards communicate with the host application via Ethernet. The target software acts as a TCP server and a multicast client, allowing the host to auto-identify all cards on the network.
RG 59 or Cat5 UTP, which is better? - Page 1
Forum section: electronics / projects

author: diegoperez
author_rank: Contributor
timestamp: December 10, 2015, 09:43:19 am
content: Hi,I'd like to set up a CCTV (with ntsc video output) and I need to connect a camera to a monitor which is 100 m far away. Aparently, it is not possible to directly connect both devices using a normal RG 59 cable due to atenuation losses. Would it be possible to solve this problem using something like thishttp://www.amazon.com/Evertech-Passive-Twisted-Pair-Video-Transceiver/dp/B00GXE92X8/ref=sr_1_8?ie=UTF8&qid=1449740406&sr=8-8&keywords=ntsc+utp?Any advice would be apreciated,Thanks,Diego

author: SL4P
author_rank: Super Contributor
timestamp: December 10, 2015, 09:49:58 am
content: Being a passive 'balun' (transceiver) - it will introduce losses within itself (twice), so RG59 alone will be better... but you could put a small low-cost/noise video amplifier at the camera end - to boost the signal (as measured at the recorder/monitoring end.There are other approaches, but they involve a bit more complexity.The use of co-ax or twisted pairs, is not entirely irrelevant, but does to some extent depend on the electrical environment around the cable route.

author: vk6zgo
author_rank: Super Contributor
timestamp: December 10, 2015, 10:25:39 am
content: Quote from: diegoperez on December 10, 2015, 09:43:19 amLong 75 Ohm flexible coax cables have been used for decades in TV Broadcasting,but there seems to a fad in some other circles to use twisted pair cables.Towards this end,a lot of false information has appeared on the 'Net & elsewhere.100m of RG59 is down by 2.53dB at 5MHz,so you will be getting a bit of high frequency fall off.A video amp with a simple cable equaliser built in will correct that with ease if you are fussy.RG6 will be better at -1.87dB at 5MHz.In your application,as it is NTSC,& not required to meet Broadcast specs,you may not need to use equalisation at all.

author: diegoperez
author_rank: Contributor
timestamp: December 10, 2015, 11:47:13 am
content: Quote from: vk6zgo on December 10, 2015, 10:25:39 amThanks for the responsesI suspected that these type of adapters might be useless, now it's confirmed.

author: MagicSmoker
author_rank: Super Contributor
timestamp: December 10, 2015, 12:24:00 pm
content: I suspect the most compelling reason to use UTP (ie - "networking") cable is cost, as Cat-5e UTP typically runs around 1/3rd the of price of "consumer grade" coax.

author: SeanB
author_rank: Super Contributor
timestamp: December 10, 2015, 07:12:11 pm
content: I used those passive converters ( really just a BNC to terminal block arrangement) as I used the other 3 pairs to feed the camera the 12V supply. Worked well enough during the day, though at night when the IR illuminator turned on the camera still operated, though with a supply of 8V.
RG Leds change the polarity from 12 to -12 V - Page 1
Forum section: electronics / projects

author: Linda
author_rank: Newbie
timestamp: August 09, 2024, 11:15:46 am
content: I have a problem with the LEDs in the diagram below, when the LEDs are installed, the polarity changes from 12V to -12V and the color does not change, where the problem is?the C is for RED color LED and Z is for the GRREN color LED

author: CaptDon
author_rank: Super Contributor
timestamp: August 09, 2024, 01:15:13 pm
content: One of the most difficult to understand schematics I have seen in years. I worked on MAZAK's with over 100 relays and those schematics made more sense!!! The person who did that relay logic in the OP's schematic should get a second job laying out Corn Mazes!!
RG or RGB SMD LED within 4.1mm dia - Page 1
Forum section: electronics / projects

author: Richard Crowley
author_rank: Super Contributor
timestamp: January 28, 2019, 06:45:36 pm
content: I have an application (low-profile video switcher control panel) where I would like to use these Panasonic EVPADK04K switches.I need R/G lighted indication (industry convention: Red = on-air, Green = preview)These switches are nice low-profile and provide a 4.1mm "hole in the middle" to deploy the lighting.But I am trying to find a nice bright R/G LED solution that would fit into that 4.1mm dia space constraint.I fear that the ordinary SMD LEDs that will fit within the 4.1mm diagonal are not bright enough to shine through the button cap.Unless I can find molded buttons, I am fabricating my own from white translucent acrylic.There are SMD LEDs that mount from the back-side of the PCB, and shine through a hole in the PCB.But I don't know what is the proper name for that style?Ideally I would like something like a fully-controlled RGB component with integrated controller (what AdaFruit calls "NeoPixel")But those are much to large to fit within the 4.1mm dia space.I suppose, worst-case I could simply use ordinary 3mm RGB (or RG) LEDs poked in from the back-side of the PCB,and fold over the leads to create a DIY surface-mount kludgy solution.

author: ajb
author_rank: Super Contributor
timestamp: January 28, 2019, 07:59:16 pm
content: If you really want RGB, what about a second PCB with the LEDs mounted behind the first with the buttons? You may need a light pipe or lens to get better light coupling, there are a number of simple cylindrical light pipes that might work.

author: mikeselectricstuff
author_rank: Super Contributor
timestamp: January 28, 2019, 08:04:40 pm
content: 2x2mm RGB LEDs are readily available and fairly bright

author: Buriedcode
author_rank: Super Contributor
timestamp: January 28, 2019, 08:56:53 pm
content: A RGB PLCC4 might also fit in there ( 3.2 x 2.8 ) but they tend to be extremely bright.Edit: stupid emotes

author: Mr.B
author_rank: Unknown
timestamp: January 28, 2019, 09:03:16 pm
content: I have used Cree 2mm x 2mm PLCC4 in small/tight spots.These ones are pretty bright.They were too bright in my particular application and I ended up using them with 35% PWM.Datasheet here:https://nz.mouser.com/datasheet/2/90/1273-CLMVC-FKA-1519109.pdf

author: Domagoj T
author_rank: Frequent Contributor
timestamp: January 28, 2019, 09:14:48 pm
content: They are called reverse mount LEDs.https://www.digikey.com/en/product-highlight/s/sunled/reverse-mount-rgb-plcc-smd-led

author: LapTop006
author_rank: Unknown
timestamp: January 29, 2019, 02:42:15 pm
content: It somewhat depends how you're planning to cover them, you need some diffusion to avoid a bright point source anyway, but even standard 0603 indicator LEDs run at full power are almost certainly brighter than you'd ever want if you use modern parts.Red & Green are on the dimmer end for LEDs, but at 5-10mA should be plenty bright enough, even through a lossy diffuse layer. (For blue < 1mA can still be obnoxiously bright)
RGB led Display with tlc5940 project, request for feedback - Page 1
Forum section: electronics / projects

author: Roeland
author_rank: Newbie
timestamp: December 11, 2020, 08:19:56 pm
content: Hello,I'm a student electronics and for a project a'm making for myself a would like to have some feedback on it.The general concept:- A 16 x16 RGB matrix with those RGB leds:https://nl.aliexpress.com/item/32384196929.html?spm=a2g0s.9042311.0.0.24a94c4d0eIKMW- Controlling all the leds with 3 TLC5940 PWM led drivers.- Scanning Row by Row.- Controling the Led-drivers with a STM32F103.Pictures from every layer ande pdf's of the schematic are below.Resistor values used befor the leds are 33Ohm (Red) and 43Ohm (Green and Blue)All the leds and components on a 4 layer pcb and will be made by JLCPCB (very cheap 4layer pcb)All comments are welcom!thanks in advance

author: tooki
author_rank: Super Contributor
timestamp: December 13, 2020, 03:43:45 pm
content: TI makes newer drivers specifically for RGB displays. I'd strongly recommend using those instead. Fewer ICs and better correction for the intricacies of full color.Or make your life much, much easier and just use addressable LEDs (like APA102C/SK9822/HD107). They'll give you excellent performance (very high PWM frequencies on SK9822 and HD107) with minimum effort, since they handle the entire LED driving internally and need only two data pins for the entire array.

author: mikeselectricstuff
author_rank: Super Contributor
timestamp: December 13, 2020, 03:57:28 pm
content: tlc5940 is a constant-current driver - you don't need resistors.

author: Roeland
author_rank: Newbie
timestamp: December 14, 2020, 04:39:14 pm
content: Quote from: tooki on December 13, 2020, 03:43:45 pmthanks for the comment.I know I could use some addressable Led's but I want to do it this way by scanning every row.Do you have any suggestions of a specific led driver? The one I'm using is actually easy to find on AliExpress and it has some cpp libraries (writing one is a little to difficult for mee).

author: mikeselectricstuff
author_rank: Super Contributor
timestamp: December 14, 2020, 06:16:01 pm
content: TLC5940/41 is a reasonable choice as the BLANK input and external clock lets you synchronise the PWM and row scanning accurately. I think TI now do some with multiplexing built in - it's a while since I looked.

author: Roeland
author_rank: Newbie
timestamp: December 15, 2020, 07:50:32 am
content: Quote from: mikeselectricstuff on December 14, 2020, 06:16:01 pmQuestion? is the library in the link below supports that synchronization between the PWM and the row scanning? Like I said before my cpp skills are not the best.https://os.mbed.com/users/Spencer/code/TLC5940/
RGB LED Light - Page 1
Forum section: electronics / projects

author: Dzambaz
author_rank: Newbie
timestamp: January 22, 2018, 11:20:05 pm
content: Hi,Few weeks ago I finished making an RGB LED light, which I would describe here as a general purpose LED light with a separate control over the red, the green and the blue light output, with no dimming capability and a potential to be used in videography or experimental photography. The design is rather simple and it is suitable as a project for educational purposes.The main component of the light is one 30W RGB LED module consisting of three arrays of red, blue and green LEDs (it is widely available from various online sources).Other components needed are aluminium heat sinks, three step-down DC/DC converters (used as LED drivers), one boost DC/DC converter (to provide powering from a wide range of input voltages), lens with a lens holder and a reflector, fan, switches, aluminium profiles and various scrap plastic for the enclosure. With proper tools, I could have made the enclosure even better but this one also came out well.The light can be powered from a wide range of input voltages, including a car battery, or a typical laptop AC adapter. It has a fuse and input inverse polarity protection. However, the RGB light outputs were not properly balanced, so the resulting white is most probably not a neutral white as one would expect.In short, these would be the technical specifications:• Switch controlled red, green and blue light output (independent or combined)• Input voltage: 9-30V DC• Input power: 32W MAX• Input inverse polarity protection and fuse protection• RGB LED module consumed power (R+G+B): 23WAgain, my need for this light was to use it as an auxiliary light for experimental photography and video and I used the opportunity while making it to record the process and make an educational video which I believe it can be useful as a tutorial for beginners in electronics.Your questions or comments related to the project are welcome.Thanks,Goran
RGB LED matrix chain limits - Page 1
Forum section: electronics / projects

author: davorin
author_rank: Unknown
timestamp: April 27, 2018, 01:59:04 pm
content: EHLO (o;I guess some or many have used or use the RGB matrix library fromhttps://github.com/hzeller/rpi-rgb-led-matrixThe author states that it would be theoretically possible to drive a chain of 32 * 32x32 panels at 100Hz refresh rate and 24bit colors...I have some 64x64 panels here I want to use...but when calculating the required clock rate I get:Code:Refresh: 60HzRows: 32 (two rows are lit at the same time)Columns: 64Clock rate for simple on/off: 122.88kHzNow when adding colours levels with 8 bit PWM the clock rate needs to be multiplied by 256, leading to a clock at 31.46MHz, which is already above the DP5220X shifter specs...So how would it be possible at all to get a larger chain setup while keeping a good refresh rate?Or did I calculate something completely wrong here? (o;

author: german77
author_rank: Regular Contributor
timestamp: April 27, 2018, 04:41:08 pm
content: I never heard of or tested this library.But talking theoretically if you can only light a led at a time you need a frequency of 245.7kHz in order to only turn on an off a led. With pwm this value will get to 62.9MHz which is impractical.This library is for raspberry which from were I know it has 2 pwm channels. That's why you get 31MHz. You should be able to lower the PWM resolution to lower the clock speeds. With 6 bit pwm you would have 64 different values, a clock rate of 7.86MHz and I bet that would look just as fine as the 8 bit pwm.

author: davorin
author_rank: Unknown
timestamp: April 28, 2018, 10:37:43 am
content: Actually PWM is only used for switching GPIO pins on/off...not for brightness control as it won't work..as you would control the brightness of two rows at once ( in case of the 64x64 panel).
RGB LED selection for battery powered device - Page 1
Forum section: electronics / projects

author: ramonmaruko
author_rank: Contributor
timestamp: May 20, 2022, 02:36:20 pm
content: I am not sure if this board or the "Beginners" board is the correct place to post this thread, since I am a beginner.I am designing a keyboard for personal use. This will be a wireless split keyboard with per-key backlight RGB LED. I will be using theLP5868 matrix driver.These are the design specifications I am looking for for the LED:If = 3mAWill work at 3.3v"Reverse mount"/bottom entrySince this will be powered by a battery, I want to limit the maximum current consumption per LED channel to 3 mA (the minimum allowed by LP5868). I also want to avoid adding a 5v rail and just want to usethe available 3.3v rail on my board.I have narrowed down my options to:T36K3BGR-05D000121U1930APF3236LSEEZGKQBKCThe APF3236LSEEZGKQBKC is not really reverse mount, but I am thinking of drilling a hole in the PCB and soldering it upside down. I am not sure of the implication sit will have on thermal dissipation.The T36K3BGR-05D000121U1930 meets almost all of the criteria I want, except it was tested at 5mA; but I guess that can work at 3mA. The specifications for T36K3BGR-05D000121U1930 is also suspicious.It listed a minimum luminous intensity @ 5mA of 900 mcd for RGB, while the APF3236LSEEZGKQBKC @ 2 mA can only output 6/20/4 typ. mcd. So I am hesitant on using the Harvatek part.Another option that I am looking at is using standard power RGB LEDs likeXZMDKCBDDG45S-9, butthe max Vf for the blue and green channels also exceed 3.3v. However looking at the charts in the datasheet, running them at If = 3mA, they should only have a Vf of around 2.7v... if I understoodthe charts correctly.So my questions are:1. Should I trust the datasheets of T36K3BGR-05D000121U1930 and Harvatek in general? I also see that they had been sued before y other companies for patent infringing...2. Is it alright to use "standard" (i.e. not advertised as low power/low vf) LEDs provided they have a Vf < 3.3v @ If = 3 mA?3. How much lumens is needed for a per key backlight RGB led for a computer keyboard? Ideally, it should be visible even with ambient light, but should not be annoying to my while I use it.
RGB LEDs Top Hat - Page 1
Forum section: electronics / projects

author: safarir
author_rank: Regular Contributor
timestamp: August 04, 2012, 02:29:43 am
content: Hi Everyone,This is not a "real electronic" project but I still want to show you a small project I am working on, it still not completed, but I want to show it to you guys. Soo there are some video:EDIT: NEW VIDEOIn this video, the link between strip 3 & 4 had a cool joint, that why there is a big difference of color.I am currently making a video explaining how I build it and another showing differents effects. But there is some specs for you:400 RGB led11400 mah batteryNXP mBed LPC1768 controllerBost Buck Converter

author: PeterG
author_rank: Frequent Contributor
timestamp: August 04, 2012, 03:39:27 am
content: Nice project..Regards

author: David_AVD
author_rank: Super Contributor
timestamp: August 04, 2012, 04:23:16 am
content: Nice. What programming language did you use to write the software?

author: safarir
author_rank: Regular Contributor
timestamp: August 04, 2012, 05:09:32 am
content: Quote from: David_AVD on August 04, 2012, 04:23:16 amHi David,Both the software and the firmware are wrote in C++. For the software, I used the qt framework. I gonna publish the source a soon as I have the time to clean them up a little.

author: safarir
author_rank: Regular Contributor
timestamp: August 04, 2012, 05:46:15 am
content: I just made a new video:
RGB Mod in Panasonic CTP-2780SF - Page 1
Forum section: electronics / projects

author: Technotronic
author_rank: Contributor
timestamp: August 22, 2024, 06:56:07 pm
content: Doing one of these on this TV, was able to get the SAMS photofact for it a SAMS 3203.https://crtdatabase.com/modding/rgb-via-muxThere is a basic diagram at the bottom of that page on the concept of the mod.Its using this as the jungle IC:https://www.alldatasheet.com/datasheet-pdf/view/13342/PANASONIC/AN5304NK.htmlPin 28-30 are RGB, and 27 (blanking pin) needs like 2-5V DC on it to activate the OSDfunction so those pins become active to the CRT. I have that much working with thatgreen switch, however the sync is messing me up.I have sort of ok test pattern from the Sencore CM2125 computer monitor analyzerbut its got vertical roll. I tried recall0 and that seems to almost give asteady image only its traveling vertically very slowly, and part of the color bars seem like thereis a pin issue near the top left corner. Image may be a little too far to the right too.Sencore settings are:Vertical F: 60.5Horiz F: 15.8KcH.Pixel: 640V.Pixel: 200From what I can tell, the sync from the Sencore goes to the Yellow(Video-in) jack on the rear panel for Video 1 so I have one of the Sync lines on the DB15 to 5 plug BNC cableon there but I cant tell if thats correct. It definitely effects the sync ofthe pic and in this video where another guy does the mod he seems to combine both the H+V syncwith 470 ohm resistors to be 1 composite sync line maybe?Theres confusion if this chip is taking TTL / Analog or digital for thosesignals? He also used coupling caps and I think some resistors to knock downthe RGB lines somewhat? Would too high a level sync cause the V.roll?Attached is a screenshot showing the video-in sync line to the IC main and then out toPin 4,5 on the jungle IC...which I guess is composite sync?My test signal from the Sencore is going into a HD15 VGA type monitor cablewith the (5) BNC connectors on the end, so there are (2) sync lines..one for V,the other Horiz. So would I need to combine them into this input jack maybe?
RGB modding sony vcr/combo - Page 1
Forum section: electronics / projects

author: pejman1998
author_rank: Newbie
timestamp: September 21, 2019, 09:43:00 am
content: hi i don't know if i posted in the right place or not if not admin please relocate it i did my best not to bother you.anyways i am trying to do a RGB mod on my vcr tv combo like eevlog guy but this is a very different model i cant find any service manual since the model label is worn out but by opening the case i got the identification of chips and ics apparently tho osd rgb seems to be digital since there are 6 pins related to rgb due to datasheet of mcu that provides the osd rgb there are R,G,B ,I ,YS ,YM related to that function in microcontroller ic , in other hand there is a jungle ic that has 3 of RGB pins beside rgb outputs with the names of Rclp,Gclp,Bclp and i dont know what does clamp means really at the end of each color but r and b are connected to pal secam ic and g is grounded by a cap . i have done rgb mods before but there were very easy to do i dont know anything about this tv combo i provided the pics of pinouts so you can give me your opinion on this project , guide me how can i mod it into rgb monitor , thanksps my remote has a model number on it and its rm-847 but i couldnt find any information about tv that belongs to this remote!
RGB to component - Page 1
Forum section: electronics / projects

author: Mrwoodchuck
author_rank: Contributor
timestamp: October 06, 2015, 07:38:41 pm
content: Hi all,I'm working on an rgb to component circuit.I'm a rookie and this circuit is building off of 3 other circuits i found on the net.its using the THS7314 rgb amp supplying the signal to a ba7230ls ntsc tv encoder, while using the lm1881 sync stripper adding it to the G in line.then from the ba7230ls the signal is put through the 2sc945 transistors some passives and out as component.I have ordered most of my parts and will be wiring up a test circuit when they come in.I wanted to know if what I have drawn out here is going to work or just blow up in my face.Any tips would be appreciated as i said im a rookie and still learning.Thanks all!

author: ajb
author_rank: Super Contributor
timestamp: October 06, 2015, 08:40:09 pm
content: First of all, you'll have a much easier time if you work on cleaning up your schematic.- Spread things out a little more so that all of your wires can be at right angles.- At the THS7314, why do you have wires terminated at the root of the pins rather than the tips? Are the pins backward in the library?- No pin descriptors on the BA7230. . .that's just asking for trouble. You want to be able to immediately be able to see if the the components are connected correctly in the schematic, if you have to refer to the datasheet to know what the pins do then you have a much higher risk of mistakes.- Never run a wire over a component. Either route the wire around from one side to the other, or flip the component to a more suitable orientation.- Positive power ports should point up, negative or ground ports should point down.Spending the time to lay out a schematic nicely in accordance with the standards and conventions will not only make it prettier, but more importantly will make it easier for you and other people to read and understand. When it's easier to understand, it's much easier to spot mistakes.

author: Mrwoodchuck
author_rank: Contributor
timestamp: October 06, 2015, 10:40:45 pm
content: Thank you for the reply,Ya i was worried how bad the schematic looked, i was just trying to get it setup for the board part of eagle that i did not put a lot of effort in the schematic.The THS7314 was a mistake on my part i made the library.BA7230 was a Library i downloaded I forgot to turn on the names.I was unaware of the power / ground ports thing but now that its mentioned it seems so obvious.Hopefully you will like the redo as this version looks a lot better.
RGB to VGA input on LCD - Page 1
Forum section: electronics / projects

author: Gusbert
author_rank: Newbie
timestamp: September 16, 2019, 01:23:02 pm
content: I have a BBC B micro with a 5-pin RGB output. I've searched on these forums and the web, but I can't find a suitable answer. Is it possible to convert from this RGB output to a VGA input on a modern LCD monitor (not TV)? If not VGA, then what would be needed? [ Attachment Invalid Or Does Not Exist ]

author: coromonadalix
author_rank: Super Contributor
timestamp: September 16, 2019, 02:20:11 pm
content: https://www.amazon.com/Video-Converter-HD9800-GBS8200-Arcade/dp/B078HNW6SJsomething like this?
RGB to YPbPr (YCbCr) conversion and bright picture issues - Page 1
Forum section: electronics / projects

author: MaarioS
author_rank: Newbie
timestamp: November 07, 2019, 09:21:17 pm
content: I'm working on a specific RGB to YPbPr (component) converter. It is supposed to connect old consoles to a modern flat 240p supportive TV. However I have an issue with luma Y output part. Here is the schematic of the current version I created:YPbPr formula is R 0.299 + G 0.587 + B 0.114 and resistors R1-R3 are supposed to do this partSometimes the picture is too bright on the top, especially if the picture is black, the picture gets bright on the top and gets even brighter after time. I noticed when I put R6 75ohm resistor as pictured, the brightness decreases a little as it should, however if I lower the resistor value even more, the picture gets screwed up overall.Right now I'm clueless on how to fix it. Does anyone have any ideas?? I can take a photo of the brightness issue if needed. Many thanks in advanceEDIT: here's the real photo of the effect (some reflection is shown but the main issue is still visible)

author: flynwill
author_rank: Regular Contributor
timestamp: November 08, 2019, 02:30:15 pm
content: Do you have a scope? If you do this should be straightforward to debug, without one pretty difficult.I would hazard a guess that there is something terribly wrong with the DC levels of the R, G & B signals or possibly they are not blanked properly, the net result is the level of you Y output is shifting shifting significantly during the vertical interval.Is is possible there already is sync on the green channel?

author: Audioguru again
author_rank: Regular Contributor
timestamp: November 08, 2019, 03:24:02 pm
content: Video is supposed to have DC coupling so that the black level is always correct. This circuit has an output capacitor that messes up the DC brightness levels.Many, many years ago high cost TVs used a "DC restorer" circuit because they did not know how to DC-couple a video amplifier.

author: tooki
author_rank: Super Contributor
timestamp: November 08, 2019, 03:26:07 pm
content: Quote from: MaarioS on November 07, 2019, 09:21:17 pmGiven that we are starting to see TVs with no analog inputs at all, wouldn't it make more sense to use an RGB-to-HDMI converter? They're readily available, from simple off-the-shelf ones, all the way to FPGA-based ones made specifically for console gaming.
rgba - reasonably good bluetooth audio  - Page 1
Forum section: electronics / projects

author: fu5ha
author_rank: Contributor
timestamp: March 15, 2021, 08:27:14 pm
content: Hey allHere's a project I'm calling the RGBA - Reasonably Good Bluetooth Audio.It's a very small Bluetooth audio receiver, DAC, and amp that is meant to attach inline to the cord of a pair of IEMs (or headphones, though for my current purposes it's targeted at a pair of high sensitivity custom IEMs I have--you could adjust the OpAmp feedback network to tune it for other devices fairly easily). It aims to provide as high-quality audio as possible while retaining reasonable battery life and its tiny form factor.It's based around the TI PCM5242 DAC and OPA1662 op-amp, with necessary power regulation and filtering circuitry and a Qualcomm CSR8675-based Bluetooth audio module that handles Bluetooth audio communication and charging the 3.7v LiPo cell.Here's a couple of renders of the front and back of the current version of the PCB, which comes in at about 5x3cm total. Just sent it off to OSHPark for fabHeres a few of images of the board layout. It's a 4-layer stack up, with PWR/Signal on layers 1 and 4 and two ground planes on the middle layers. I tried to prioritize the cleanliness of the signal path, then the power train going into the analog side of the DAC, then power into the opamp and everything else fits in around those.Finally, you can check out the schematic rendered as PDF here:https://github.com/termhn/rgba/blob/master/rgba.pdfand you can also check out the KiCad files and BOM in the Git repo here:https://github.com/termhn/rgbaThis is my first audio circuit design... it's based a lot around TI reference designs and application notes about HiFi audio/headphone amplifiers from them. Let me know what you think
RGMII voltage levels - Page 1
Forum section: electronics / projects

author: abquke
author_rank: Regular Contributor
timestamp: June 28, 2022, 07:26:25 pm
content: Are the voltage levels of a RGMII device the same as its DVdd supply? That's the guess I have that makes the most sense...A more sticky question might be regarding mixed voltages between two devices. Can they be mixed (1.8 and 2.5 say) as long as the lower voltage device's Vhigh > V_high-min of the higher voltage device?

author: NiHaoMike
author_rank: Super Contributor
timestamp: June 28, 2022, 10:17:12 pm
content: Quote from: abquke on June 28, 2022, 07:26:25 pmIf the lower voltage device outputs a high that's a comfortable margin above the threshold at which the higher voltage device calls high, yes. The other way around will need measures to attenuate the voltage if it's not tolerant of the higher voltage. The trickiest to deal with are bidirectional lines.

author: ajb
author_rank: Super Contributor
timestamp: June 28, 2022, 10:53:02 pm
content: Generally the IO voltage will be the same as Vdd unless otherwise specified. Some devices (among PHYs and switch ASICS anyway) will have separate VddIO pins to power the IO buffers so that the IO voltage can be selected separately from the operating voltage(s). You could think of these parts as having level-shifters built in, conveniently preconfigured with the correct IO directions.

author: abquke
author_rank: Regular Contributor
timestamp: June 28, 2022, 11:42:45 pm
content: I'd read a TI App Note on voltage translation (SCEA065B) where they showed off a SN74AXC8T245 translating a RGMII bus. I got all excited only to find that the SN74AXC8T245 didn't seem to be available. I asked about a near-replacement on the TI E2E forums on the important parameters and the response was more or less "Yeah, we don't guarantee anything for that application".
RGY led indicator circuit - Page 1
Forum section: electronics / projects

author: ton88
author_rank: Newbie
timestamp: February 24, 2020, 07:40:09 pm
content: Hello,Iam using a RGY led on a ethernet switch and want to use each color one at a time to indicate the current ethernet speed,the switch provides 2 led pins per port that are active low(pulsing or solid) and a truth table to indicate the speed.The only problem is to indicate a speed of 10mbps both led pins on the switch are pulled low.So now i would need some sort of logic to switch between which color to have on iam thinking of using some AND gates the max current i have limited on each color is 10ma.Iam not really sure if there is another way to achieve switching between the led colors.Any input is appreciated thanksthere should be a image attached for the led truth tablehttps://i.postimg.cc/wBF0KG9F/led-pins.png
Rhumkorff Coil Restoration - Page 1
Forum section: electronics / projects

author: Terry Bites
author_rank: Super Contributor
timestamp: August 08, 2024, 05:08:20 pm
content: This is a you genuinely know it or you don't kind of question.I've plenty of my own opinions.I've been given an antique Rumkorff coil to restore.It's in bits an looks like some on had a go an gave up. Electrically it's fine, shockingly good in fact. Whacked by my LCR meter!I've seen a lot of photos of interuptor mechanisms which are mostly simple break types. Some bizarre contraptions. I'm still trawling ancient patents.My coil has three posts and two springy arms which I'll remake. I've tried to make sense of the various configurations that might work but I'm still not happy.BTW, can you hard silver solder Tungsten to brass?Any ideas?Ta
Ribbon cable connector help - Page 1
Forum section: electronics / projects

author: Hornnumb2
author_rank: Regular Contributor
timestamp: September 17, 2023, 10:21:01 pm
content: I broke the locking tab off this connector and need to order a new one. Do I just count the pins or what else do I measure? Thanks Michael

author: themadhippy
author_rank: Super Contributor
timestamp: September 17, 2023, 11:38:56 pm
content: Quotethe pin pitch,thats the distance between pin centers

author: zapta
author_rank: Super Contributor
timestamp: September 18, 2023, 12:02:23 am
content: Also notice if the contacts are on same or opposite sides if the cable.

author: bostonman
author_rank: Super Contributor
timestamp: September 18, 2023, 12:36:43 am
content: If you're definitely replacing it, I'd try removing it to look for a part number; or some prefix that will help narrow down the manufacture (unless the part number is visible from the top).I had a similar issue with a ZIF connector, found a marking on it, contacted the company, and they helped me find the replacement.
Ribbon cable shorting jumper? - Page 1
Forum section: electronics / projects

author: Alex Eisenhut
author_rank: Super Contributor
timestamp: October 20, 2021, 09:09:41 pm
content: I have a ribbon cable with plain old .100" IDC connectors on each end. However turns out I need to short two pins together on the cable. Is there something I can crimp on to the cable to connect between two adjacent conductors?I could just buy the smallest IDC and solder the pins across and crimp that. I am talking almost DC logic signals, no worries.Just sending out feelers here.

author: EPAIII
author_rank: Super Contributor
timestamp: October 21, 2021, 06:02:19 am
content: Someone may make such a device, but I have never seen one.I have made tools to remove IDC connectors from paper clips: flatten the ends and bend at a right angle then use to gently pry the plastic catches loose. If you can move one of those IDC connectors a bit from the end of the cable, you could then trim all the wires except those two off flush. Then strip those two wires and solder then together. Add a bit of insulation (brush on?) and epoxy it down to the side of the connector.
Ribbon cable spacer thingy - Page 1
Forum section: electronics / projects

author: itscoldoutside
author_rank: Contributor
timestamp: August 11, 2025, 02:00:44 pm
content: I am creating a custom ribbon cable in kicad that I am going to get a small run made by one of the Chinese companies. Anyway it's nearly finished but I am not sure what the thicker part is called that helps it stay in the connector and more importantly what it's called in kicad.This is just a stock picture but I am talking about the blue part, some times it's brown.Thanks.

author: sd
author_rank: Unknown
timestamp: August 11, 2025, 02:29:01 pm
content: It's called a stiffener.

author: ataradov
author_rank: Super Contributor
timestamp: August 11, 2025, 03:56:46 pm
content: It is not called anything in KiCad. Those things are specified in manufacturer-specific way. It will be either an option on the order form, or you will need to supply a separate mechanical drawing.You may create a custom layer and place it there, but this will still need to be explicitly communicated to the manufacturer.

author: gamalot
author_rank: Super Contributor
timestamp: August 11, 2025, 04:27:34 pm
content: I remember that JLCPCB website has relevant content for reference, although you may be working with other manufacturers.

author: tooki
author_rank: Super Contributor
timestamp: August 11, 2025, 05:21:16 pm
content: Quote from: itscoldoutside on August 11, 2025, 02:00:44 pmJust FYI, for historical reasons, that is called a "flat flex cable" (FFC), and not a "ribbon cable", because the latter term was already taken ages ago for the cables that are made of individual round wires whose insulations are fused together side by side.Also, if you're talking about making a custom one in KiCad, then you're probably not actually thinking of an FFC, but of a flex PCB. The PCB manufacturers tell you how to define the features needed (glue, stiffeners, etc.)
Ribbon cable strain relief - Page 1
Forum section: electronics / projects

author: btfdev
author_rank: Contributor
timestamp: March 29, 2012, 02:33:54 am
content: Hello TeamCan anyone tell me where I can get this kind of molded strain relief for ribbon cable?Thanks, BTFDev

author: PeterG
author_rank: Frequent Contributor
timestamp: March 29, 2012, 08:21:22 am
content: You could start here.http://au.element14.com/jsp/search/browse.jsp?N=203151&ref=lookaheadRegards

author: dfnr2
author_rank: Regular Contributor
timestamp: March 29, 2012, 12:51:39 pm
content: That does not look like a commodity part.
Ribbon cable with pin ends suitable for 2mm pitch PCB receptacle - Page 1
Forum section: electronics / projects

author: perdrix
author_rank: Frequent Contributor
timestamp: January 31, 2022, 10:57:47 am
content: I can find loads of 6" (15cm) male to male ribbon cable jumper sets such as:https://www.ebay.co.uk/itm/122177310007Those work fine with 0.1" pitch connectors, but the plastic bodies of the pin connectors are too large to allow plugging into a 2mm pitch connector (Samtec SQT-105-01-F-S)Does anyone know of a similar cable with smaller pin housings so it will work with 2mm pitch?ThanksDavid

author: Ian.M
author_rank: Super Contributor
timestamp: January 31, 2022, 11:54:43 am
content: I did a bit of digging - Samtec don't give the contact's mating pin specs directly, but if you dig in the data for mating connectors, you can find its a 0.020" (0.50 mm) square pin, 0.090" (2.29mm) long. Unfortunately the common 0.1" pitch headers use 0.025" (0.635 mm) square pins, so even if you stripped the shells and used heatshrink to get them closer together, the common 'duPont' clone pins aren't going to do the job - they'll strain the contacts so the connector will never be reliable again with the proper mating plug.Protoadvantage do a 6 pin SIL 2mm to 2.54mm bare adapter PCB you could use -http://www.proto-advantage.com/store/product_info.php?products_id=3800080- to break it out to 2.54mm pitch.Otherwise you are looking at finding a compatible 2mm pitch connector system with shells, crimp pins and a reasonably affordable crimp tool. If that was easy, I'd have suggestions for you . . .
RIDEN 6000 Series Master/Slave or Tracking Between Controllers  - Page 1
Forum section: electronics / projects

author: AJ3G
author_rank: Regular Contributor
timestamp: November 08, 2020, 05:14:44 pm
content: All:I a in the beginning stages of collecting parts for a SMPS Build using the RIDEN front ends. Due to the cost, I am considering using multiple RIDEN Front ends to make a quasi multi channel PSU. I wonder if anyone has looked at having one RIDEN front end as a master, which then controls another controller in a tracking/slave fashion?It would seem based on some of the high level documentation I have been able to review, at a minimum this should could be accomplished through the WI-FI ModBus Protocols, but I do not have a controller to do more sniffing around. If anyone has a definitive answer, or has tried this before, I would like to hear your thoughts.Rich

author: S. Petrukhin
author_rank: Super Contributor
timestamp: November 10, 2020, 02:12:03 am
content: Quote from: AJ3G on November 08, 2020, 05:14:44 pmThe RD6006 has some good PC software. I don't remember exactly if there is synchronous control, but it can manage multiple blocks for sure.

author: AJ3G
author_rank: Regular Contributor
timestamp: November 10, 2020, 04:31:04 pm
content: Hello:That is good information. I think it does deserve a closer look. I will have to wait for my 6018's to arrive in the USA, so I have no actual hardware to test this theory at the moment. I did land a 65V 35Amp supply to use as the back end for the controller, which did arrive. I also have a enclosure to fit the supply, two controllers, AC Input Filter, Fuse, and some additional DC Distribution Banana Jacks.Maybe in a week or so I will have a post about how the build is coming along.Rich
RIDEN 6018 Ripple Specification - Page 1
Forum section: electronics / projects

author: AJ3G
author_rank: Regular Contributor
timestamp: December 19, 2020, 06:06:30 am
content: All:I am running a couple of the RIDEN 6018’s through some test for documentation purposes. I just completed testing the ripple at the output while running 50VDC at 10A. Their spec seems to indicate that I should encounter something closer to 250mV of ripple, and I am seeing 11.3mVp_p accept my voltage and loading is higher than how they indicated they tested it.Does anyone off hand know if this specification is incorporating the SMPS they sell with 6018 controller? I am using a better SMPS than what they sell as a package eat or kit to go along with the controller.Rich
Rifa Transparent Yellow X2 Caps BAD In Box - Page 1
Forum section: electronics / projects

author: Bushougoma
author_rank: Regular Contributor
timestamp: October 26, 2017, 01:39:12 am
content: I was just browsing E-bay today and found someone selling the old Rifa transparent yellow X caps that are known to explode in older electronics.These were new in box and what intrigued me was that they show the typical cracks that ones installed in old electronics do just before they are about to fail. So even in the box without seeing any use they develop the cracks that lead to their demise.Unfortunately 5 unsuspecting buyers purchased some I hope they have plenty of air freshener when they decide to blow.

author: Keicar
author_rank: Regular Contributor
timestamp: October 26, 2017, 01:45:49 am
content: Oh dear - must resist the temptation to shop for NOS Schaffner line filters...
Right approach to calculate Temperature from voltage and resistor for thermopile - Page 1
Forum section: electronics / projects

author: radhika
author_rank: Regular Contributor
timestamp: July 24, 2020, 01:46:29 pm
content: Hi all, I am working on contactless thermometer using TSP434 thermopile detector. I didn't found much data on datasheet. But, when I tested, I got 0.01uV as output V from pin 1 and I used LTC1050CNB Opamp to amplify it.I am using PIC16F microcontroller to get the temperature display on datasheet. Though, I just tested the voltage variation on room temperature only. I am unable to get temperature, because I don't know the right formula for it. I have followed this tutorialhttps://www.instructables.com/id/Thermopile-Sensor/but I am not sure about my reading. I got thisthermopile value = 0.00thermistor value = 862.00ambient temp = 88.12object temp = 117.96thermopile value = 0.00thermistor value = 861.00ambient temp = 101.40object temp = 140.48thermopile value = 0.00thermistor value = 861.00ambient temp = 101.40object temp = 140.48thermopile value = 0.00thermistor value = 861.00ambient temp = 101.40object temp = 140.48from the code by using arduino added on the link. Do you have any idea, how do I get right formula for thermopile TPS434? Thanks

author: bjbb
author_rank: Contributor
timestamp: July 24, 2020, 04:13:35 pm
content: web.sensor-ic.com:8000/ANFANG/TPS334_R3.pdf