hybridfree/eevblog-posts huggingface dataset:
Car Switch Relay Arduino Project - Page 1
Forum section: electronics / projects

author: numloxx
author_rank: Contributor
timestamp: November 04, 2017, 02:36:48 pm
content: Hi all,I'm thinking about building a panel of switches to operate various things in my car... 3 radios, a few other things, and someone suggested using an Arduino Touchscreen to operate all the relays..I don't really know much about this sort of thing, so looking for suggestions and advice on how to get started?

author: TomS_
author_rank: Frequent Contributor
timestamp: November 04, 2017, 07:34:28 pm
content: Everything is touch screen this and touch screen that these days.Whats wrong with good old fasioned toggle switches if all youre doing is switching things on and off?Unless you need some complicated startup sequences or to generate some effects, perhaps some interlocking (which could be achieved with relays mind you...), or external communications/logging, I dont see the need to complicate things with an Arduino or other microcontroller?

author: Mjolinor
author_rank: Frequent Contributor
timestamp: November 04, 2017, 07:49:29 pm
content: Or at the other extreme, you could write an Android app to talk to your Arduino and there you go.

author: numloxx
author_rank: Contributor
timestamp: November 05, 2017, 08:07:00 am
content: Hmm, true. My original plan was physical switches, but the touchscreen idea looked pretty cool. Seems very complicated though

author: Ian.M
author_rank: Super Contributor
timestamp: November 05, 2017, 08:26:32 am
content: Individual physical switches can be operated by touch without taking your eyes off the road. You have to look at a touchscreen to operate it which is unsafe if you are the driver unless you pull over. I leave aside any issues like whether or not operating switches on an aftermarket accessory might legally count as distracted driving in your jurisdiction.
Carbon Pile Audio Amplifier - Page 1
Forum section: electronics / projects

author: Mr. Coffee
author_rank: Regular Contributor
timestamp: June 15, 2015, 04:25:14 pm
content: Here's a little oddity I made. I wanted something to turn an audio signal to a high impedance piezo earphone piece into one I could play over an earbud or small speaker out loud. It uses the vibration of the piezo to vary resistance and battery current through a graphite point contact to reproduce audio with power gain...like the old telephone system carbon mic repeaters.cheersRob

author: calexanian
author_rank: Super Contributor
timestamp: June 15, 2015, 05:56:59 pm
content: How well does it work?

author: SeanB
author_rank: Super Contributor
timestamp: June 15, 2015, 06:16:15 pm
content: Lousy gain, noisy and poor bandwidth, but as a power amplifier or generator control it is great, provided you can keep it cool enough.

author: Mr. Coffee
author_rank: Regular Contributor
timestamp: June 15, 2015, 09:47:33 pm
content: Quote from: SeanB on June 15, 2015, 06:16:15 pmPretty much so, as compared to a tube or transistor base amplifier. The gain though, is pretty good.But it does work just well enough for its intended purpose, and uses no factory made amplification devices--just a piezoelectric element. A moving coil will work, too, but needs a transformer to keep the input impedance high enough to not seriously load a crystal receiver. If I had some sound powered phones and an appropriate transformer, that would be fun to experiment with.cheersRob
Careless reflowing - Page 1
Forum section: electronics / projects

author: itdontgo
author_rank: Regular Contributor
timestamp: March 09, 2016, 08:11:24 pm
content: Hi,I've got a prototype PCB here and have had to use used chips that have been hot-air de-soldered from old PCBs. These have a pad on the bottom and so need some serious heat to move them! I've had issues with these chips and could not find a fault with the rest of the circuit although it did sort of work. I tried more carefully to desolder a 3rd chip and the circuit behaves much better.Can you shift the spec of a chip with the hot air? I was surprised because it still worked but did not start-up properly. Anyone come across this? My concern is that the PCB is on the edge of not working and a chip slightly out of spec stops it so the heat would have had to have shifted the spec considerably for me to be confident in it.Michael

author: KL27x
author_rank: Super Contributor
timestamp: March 09, 2016, 10:48:02 pm
content: Personally, the only things I have ever botched through high heat are ceramic resonators. On checking the datasheet for the max temps and reflow curve, whoa! Some of these things are VERY sensitive to heat.QuoteI wonder if your chip relies on an internal ceramic resonator for a clock. Perhaps one on which the startup power-on enable timer relies. Maybe it got cooked.Just vapid speculation, though. I've never botched an IC through hot air removal, before. (To my knowledge, anyway!)

author: John_ITIC
author_rank: Frequent Contributor
timestamp: March 09, 2016, 11:12:50 pm
content: Quote from: itdontgo on March 09, 2016, 08:11:24 pmYou have to "soak" the whole board from the bottom with hot air (approximately 150 deg C). Then you don't need too much heat from the top.

author: uncle_bob
author_rank: Unknown
timestamp: March 10, 2016, 12:43:06 am
content: Quote from: John_ITIC on March 09, 2016, 11:12:50 pmHiThere are a lot of variables here:1) How much heat was used to remove the parts from their old boards?2) Were the parts damaged before they were pulled (over voltage ...)?3) How were the parts stored after they were pulled (ESD etc)?4) How well are the temperatures on your hot air system controlled / set?5) How is solder put down on the new board?6) How was solder removed from the "pulled" parts?7) Were leads bent / damaged on the pulled parts?That's only getting into the obvious parts of the list. If you have parts with ground pads in the middle of the chip, there's a full list just for them....Bob
Carprog china clone missing ic?! - Page 1
Forum section: electronics / projects

author: Hagis2k
author_rank: Regular Contributor
timestamp: August 31, 2022, 04:21:35 pm
content: So I bought a chinese clone of Carprog and I realized that one of the IC circuits on mine isnot even populated, its an transponder IC TMS3705 that seems to be forgotten at factoryI doubt the transponder function will work properly without it?I have been looking to buy one of these for a long long time, and I been checking pcb designsand layouts on different forums and blogs but I have never seen a pcb with a missing ic yetlol guess I am the lucky sucker to get the first maybe lolbut no worries I can put one one too.I really doubt that it will work as intended without the ic missing?It is called IC1 in the schematics that I attached...The missing IC datasheet etc:https://www.ti.com/product/TMS3705and the ic next to it that is populated is:https://www.nxp.com/products/rfid-nfc/hitag-lf/hitag-reader-solution:HTRC11001T

author: thm_w
author_rank: Super Contributor
timestamp: August 31, 2022, 10:22:03 pm
content: TMS3705 seems to be expensive and out of stock from TI.Maybe it will work for some features and not others? Can you test it.

author: Hagis2k
author_rank: Regular Contributor
timestamp: August 31, 2022, 11:30:40 pm
content: Yeah I been looking at it but then I think the seller should mention it too, I shall let him know for sure.

author: coromonadalix
author_rank: Super Contributor
timestamp: September 01, 2022, 01:09:50 am
content: Even if you put / add this ic, if the eeprom firmware doesn't have it ... it will be no usei'm registered on a few forums about obd stuff for my truck, i mostly see the photos with this ic

author: Hagis2k
author_rank: Regular Contributor
timestamp: September 01, 2022, 03:36:42 am
content: Unless I flash it with the right firmware too yeah it adds a bit more work lol.

author: Hagis2k
author_rank: Regular Contributor
timestamp: October 10, 2022, 05:15:02 pm
content: So finally won my battle with AliExpress took me weeks but getting 50% off the price, as the unit does not match the listing. Could be a good thing for other users to check if their units are complete, and I urge other users that might run into the same problem is to fight this. They even gave me the wrong return shipping address, but after a week fighting with them they realize this is considered as fraud. I even made it clear to them that if I have to I will file a fraud case with the UK Police and told them that I will send an 11 pages long complaint to AliExpress in London. After that things changed rather quickly and a refund was processed in a few hours haha.Look at the return address LOLAnd I told them exactly how I did feel and I spent $1407 only this year and they are about to lose me as customer, been spending way to muchmoney there over the last 10 years haha.
Cascaded 5 level MLI  - Page 1
Forum section: electronics / projects

author: salem1
author_rank: Newbie
timestamp: April 10, 2025, 05:58:46 am
content: Hello everyone,I'm designing a 5-level cascaded multilevel inverter (MLI) using two isolated H-bridges and would appreciate feedback on my power supply configuration. Here's my current setup:Key Components4x Isolated Gate Drivers: UCC21551CDWKR (dual-channel)Isolated DC/DC Converters:Input-side: 1x converter (6.5–32V input → 5V output) powers:This converter supplies 5v to All 4 drivers' input sides (PWM logic) and to the Current sensors (ACS732).Output-side: 2x MEV3S0515SC (+15V isolated converters):One for HB1's 2 drivers.One for HB2's 2 drivers.Grounding SchemeInput Side (Control):5V converter output ground is shared with MCU ground, Current sensor grounds and Drivers' input-side grounds.QuestionsIs it correct to use separate MEV3S0515SC converters for each H-bridge's drivers? And is the GND correctly labeled?Are there risks in sharing the same 5V supply for drivers and sensors?In this case do I need 5 external sources? 2 for isolated H bridge (my H bridge needs 60v) and 3 external supply for the DC/DC converter ?

author: mtwieg
author_rank: Frequent Contributor
timestamp: April 10, 2025, 05:51:13 pm
content: A few remarks:1. I'm guessing HIGHSRC_H2 is supposed to connect to HIGHSRC_H32. All your isolated gate drivers have their VDDA and VDDB tied together. This won't work.3. It looks like U5 and U10 are intended to provide the secondary side power for the gate drivers, but their -Vout pins are tied to GND_S1 and GND_S2. These nets are not referenced anywhere else in the schematic. I'm guessing these are supposed to be LOWSRC_H1/2 and LOWSRC_H3/H44. Also it's not clear what the difference between GND, GND_P, GND_P1, and GND_P2 is.5. The IP+ and IP- pins of your current sensors are shorted together on page 5.Overall it's an extremely difficult schematic to read, despite the circuitry not actually being very complex. Poor organization makes these sort of trivial mistakes much more likely. I'd suggest the following:1. Assigning multiple names/labels to the same net (for example LOWSRC_H1, LOWSRC_H2, GNDHB1, VBAT-) in particular in particular should be avoided. Four names for one net is insanity.2. When you have a design with multiple isolated "grounds," it's best to put group components which share a common GND. Instead, you've put your FETs, gate drivers, and isolated DCDC converter on separate pages. I'd suggest devoting a page to each half or full bridge, containing the FETs, gate driver, and isolated supplies.

author: salem1
author_rank: Newbie
timestamp: April 11, 2025, 10:32:52 am
content: Thank you so much for the comments. I will correct my schematics accordingly.
cascading 74hC163 sync counters - Page 1
Forum section: electronics / projects

author: Dan Moos
author_rank: Frequent Contributor
timestamp: December 10, 2017, 12:59:10 am
content: Whats the proper way to cascade these counters? Its the carry output pin that confuses me. Shouldn't i just send the terminal count pin of the first chip to the clock enable of the second?

author: David Hess
author_rank: Super Contributor
timestamp: December 10, 2017, 06:25:47 am
content: In the simple case, the ripple carry output goes to both of the enable inputs of the next counter:http://wakerly.org/DDPP/DDPP4student/Supplementary_sections/Cntr.pdf

author: tggzzz
author_rank: Super Contributor
timestamp: December 10, 2017, 09:39:11 am
content: Figure 1 inhttp://ee-classes.usc.edu/ee459/library/datasheets/sn74162.pdfCaution: I haven't bothered to check the hc version is internally the same.
cascading dc-dc converter mc34063 - Page 1
Forum section: electronics / projects

author: TuralH
author_rank: Newbie
timestamp: November 15, 2024, 01:13:47 pm
content: have assembled a cascade converter circuit. My main goal is to accumulate a voltage of 80 volts on a C6 1000uf capacitor in about 6-8 seconds. The problem is that I am using a 3.7 V battery. If I assemble a circuit with only one cascade and try to accumulate 80 volts from 3.7, then the energy accumulation occurs very slowly, that is, it takes about 20 seconds, but I have tried to do it with other DC-DC converters and it works, but the only problem, as it seemed to me, is that there should be capacitors with a large capacity between the converters. When I use this circuit, the voltage drops to 2 V instead of 10 volts. What could be the problem? In the peak current of the inductor or in the circuit itself? How else can I achieve this voltage of 80 volts for a 1000 UF capacitor?

author: Andy Chee
author_rank: Super Contributor
timestamp: November 15, 2024, 10:47:45 pm
content: Don't double posthttps://www.eevblog.com/forum/beginners/dc-dc-boost-convetter-cascade-(series)/The obvious reason why it doesn't work is because the GND references between the two converters are common. In order to have any chance of working, the GND references should be separate.
Case (38x22x8 cm) for my project? - Page 1
Forum section: electronics / projects

author: stevepe
author_rank: Newbie
timestamp: June 08, 2020, 05:23:56 am
content: Hi everyone,I started my corona project a few months back and am making good progress. Now I am at a stage where I am thinking about final looks and a case for the thing. Am quite naive when it comes to case design and am hoping to get a couple of pointers here that lead me in the right direction. What I am looking for is a simple case like this (attached) what I have come up with in Fusion 360.Now that I have a shape, I am looking for a cost effective way to derive engineering drawings so that I can get 10 pcs done via Alibaba and possibly more later down the line. Price point should defs be below $20 per piece delivered to Germany, anodised Aluminium is a humble hope of mine, plus engraving on the front and back. Is this reasonable?I imagine this being a rather standard problem and appreciate your input to get me over this final hump.

author: Wimberleytech
author_rank: Super Contributor
timestamp: June 08, 2020, 07:50:28 pm
content: Quote from: stevepe on June 08, 2020, 05:23:56 amI suggest you get a 3D print first to make sure that everything fits the way you want.
Case capacitive coupled to Vcc and GND - Page 1
Forum section: electronics / projects

author: eTobey
author_rank: Super Contributor
timestamp: January 03, 2024, 09:50:12 am
content: Hi,i wonder, if anyone knows what this coupling is for:I would have thought, that just connecting it to GND would be good enough? Its the controller of an ebike motor.Cheers,Toby

author: Ian.M
author_rank: Super Contributor
timestamp: January 03, 2024, 10:03:39 am
content: It provides RF grounding for EMI while avoiding any risk of current flowing via the mounting hole pads, possibly melting undersize ground tracks, if the negative feed to its power in terminal comes loose.

author: magic
author_rank: Super Contributor
timestamp: January 03, 2024, 10:20:13 am
content: This explains the AC coupling, but not the coupling to 50% of VCC rather than to GND.Normally if GND is grounded, such connection would put 50% of VCC ripple on the case. Usually a cap is placed between the case and GND alone.But this is a floating circuit, so maybe they figured that its average potential is constant and equal to the midpoint between BAT- and BAT+, hence such grounding.

author: Ian.M
author_rank: Super Contributor
timestamp: January 03, 2024, 10:23:27 am
content: ... or they wanted it to work equally well (or at least equally poorly) for positive ground and negative ground vehicles.

author: wraper
author_rank: Unknown
timestamp: January 03, 2024, 10:23:45 am
content: I've seen plenty of bad engineering to first assume that engineers had no clue what they were doing rather than it actually serving some valid purpose.

author: wraper
author_rank: Unknown
timestamp: January 03, 2024, 10:39:42 am
content: On second thought this could potentially reduce EMI created by the circuit. However only if hardware is laid out in a quite specific way.

author: magic
author_rank: Super Contributor
timestamp: January 03, 2024, 10:47:12 am
content: Quote from: Ian.M on January 03, 2024, 10:23:27 amHmm, are e-bike batteries electrically connected to the frame like in cars? I assumed the whole thing would be floating.

author: Ian.M
author_rank: Super Contributor
timestamp: January 03, 2024, 10:50:05 am
content: Some cheap manufactures cant resist the temptation of using frame ground as return for low current accessories, even though its less than ideal from corrosion and reliability viewpoints.
Case to house dual rail adjustable PSU - Page 1
Forum section: electronics / projects

author: Aethelstan
author_rank: Contributor
timestamp: January 16, 2018, 05:42:04 pm
content: Hi folks. I have decided to make a dual rail PSU, I have a decent grasp of the electronics side but I am struggling to find much regarding how a case would be specified. There are lots of project boxes to choose from such as aluminium, plastic or a combination of the two, and I can 3d print something in ABS if needed. Obviously if I were to have any exposed metal then I would have it earthed, but would I be better off having something completely plastic to avoid an earth, as in class 2 device? My feeling is to use/make a plastic box with a sheet aluminium plate at the front and rear, both bonded to earth, but that's based on a gut instinct rather than any concrete data or theory. On a related note, the toroidal transformer I have for the project has a metal bolt to mount to the chassis. If I were to go for a totally plastic case, could I use a nylon bolt instead?

author: CopperCone
author_rank: Super Contributor
timestamp: January 16, 2018, 06:00:04 pm
content: Easier to make a metal box then earth front and back with a wire so long you use star washers that dig into the metal.Metal will also sheild external emissions and supress internal emissions.

author: David Hess
author_rank: Super Contributor
timestamp: January 17, 2018, 04:41:20 am
content: It may be possible to use a metal enclosure as the heat sink for the power pass elements if required.
Cased Universal NiCd/Lithium battery charger project – NOT Arduino based please! - Page 1
Forum section: electronics / projects

author: Chris56000
author_rank: Frequent Contributor
timestamp: January 13, 2022, 11:30:21 am
content: Hi!I'm looking for a decent project write–up for a bench–sized universal NiCd/NiMH/Lithium battery tester/charger – I do remember coming across one about three years ago but I can't remember where I found it – I think it was PIC based and had a character 1602 LCD!(NO stupid Arduino rubbish or Chinese modules please – they don't work and I'm fed up trying to unravel shitty code or turf out blown up Chinese specials – at least a project using a PIC is far less likely to have "bugs" or "howlers" in the code as authors won't want to commit to programming unless it works!)Chris Williams

author: Phil_G
author_rank: Regular Contributor
timestamp: January 13, 2022, 01:00:31 pm
content: This doesnt answer the question, but its just a suggestion - for £25 you could have a brilliant charger and put your own efforts into something more rewardinghttps://www.hobbyrc.co.uk/isdt-q6-nano-200w-dc-chargerMy own Q6has been in constant use for three years now, highly recommended.[I know, I know, I'll get back in my box now...]Phil
Cases and Enclosures - custom unusual examples wanted  - Page 1
Forum section: electronics / projects

author: ez24
author_rank: Super Contributor
timestamp: June 13, 2015, 05:16:40 pm
content: HiA few years ago (about 40) a friend broke his radio case and put the guts into a cereal box with the controls on the front of the box and it was cool. His roommate threw it away thinking it was an empty box of cereal.I know people use mint tins for arduino projects.I was wondering what unusual cases people have used for their electronics projects. Not the normal plastic or metal enclosure cases that are made for electronics.I am thinking about candy boxes, cigar boxes, cereal boxes, etc., with wood cigar boxes at the top of my listSome pictures would be nice.thanks

author: miguelvp
author_rank: Super Contributor
timestamp: June 13, 2015, 05:45:27 pm
content: I made a case for my Jetson TK1 dev board out of a Cypress pioneer shipping box.Other than that I did make a monitor out of a pizza box:I then upgraded it to a fine wines box:

author: mikeselectricstuff
author_rank: Super Contributor
timestamp: June 13, 2015, 06:52:27 pm
content: Urine specimen jar. The nice thing is that this was a perfect fit for an existing board from a previous project - this version was to fit in the neck of a weather balloon to light it up different colours as it bounced around an audience.

author: atferrari
author_rank: Frequent Contributor
timestamp: June 14, 2015, 12:56:20 am
content: CD reader. Used the enclosure plus the plastic front / rear panels. Enclosure was cut at about 3/4 of its length.

author: tautech
author_rank: Super Contributor
timestamp: June 14, 2015, 01:26:34 am
content: My crappy old dim bulb tester, PC PSU case.

author: atferrari
author_rank: Frequent Contributor
timestamp: June 14, 2015, 11:38:52 am
content: Quote from: tautech on June 14, 2015, 01:26:34 amThe switch looks like a very OLD one, isn't it?
Casio F91W buzzer? - Page 1
Forum section: electronics / projects

author: Deku Tree
author_rank: Contributor
timestamp: July 24, 2020, 03:17:12 pm
content: I'm working on a project to replace the main board on the Casio F91W with my own design. The original has a small beeper/buzzer which I believe is piezoelectric, but I can't find anything smaller than this to replace it:http://www.puiaudio.com/pdf/SMT-0540-T-7-R.pdfThe original buzzer is round, with a 3mm diameter and 1.4mm height. Something of the same dimensions would be best as there is a small recess in the housing for the buzzer, anything larger will require modification to the case. If not piezo what other other small buzzers/beepers are typically used in watches/pagers/etc? The watch runs off of a single CR2016 which gives me a drive voltage between 2 and 3 volts.Here's an image of the original board and buzzer:https://imgur.com/a/tSrtCqr

author: Zero999
author_rank: Super Contributor
timestamp: July 24, 2020, 06:28:18 pm
content: The product you've linked to is an electromagnetic transducer.Are you sure the object the calipers are measuring in the photo, is a buzzer? It looks like an inductor.I've opened similar Casio watches before. The piezo buzzer is normally integrated into the stainless steel back and consists of a wafer of piezoelectric crystal fixed to the metal, presumably with a conductive adhesive.

author: Deku Tree
author_rank: Contributor
timestamp: July 24, 2020, 07:16:30 pm
content: That makes more sense, there is a white piece of what I thought was tape on the back. It looks like white electrical tape. Think that's it?

author: Zero999
author_rank: Super Contributor
timestamp: July 24, 2020, 09:13:05 pm
content: Quote from: Deku Tree on July 24, 2020, 07:16:30 pmIt's normally a disc on the back, which is connected to the PCB via springs.
Cassette recording tape waveforms - Page 1
Forum section: electronics / projects

author: e.sotillet
author_rank: Contributor
timestamp: June 17, 2023, 05:00:34 pm
content: Hi folksI'm working on a audio cassette recording system. I'm able to "read" the cassete but the recording is not working too well, the sound is distorted and I want advice about how should looks the waveforms in different stages of the recording system of a cassete.I'm using a bias signal of 85kHz and the following heads, I could not find any datsshet about them.This is the record's head bias signal at 10V per division. This signal is injected using a 220pF + 50k trimmer from the 40Vpp 85kHz signal.This is the 40Vpp 85kHz signal, I have 4ohm shunt resistor in erase head and I measure 75mA of current. I can erase perfectly any commercial tape:I added a 10ohm shunt resistor in the recording head and this are the waveforms, first is at 5mV per division with no modulation. I have 10mV peak, so 1mA is passing through the recording head :Later, the same test point in the shunt resistor but now with a 1kHz modulation signal. The same 5mV per division.And finally, the waveform at the top of the recording head, now at 5V per division with the 1kHz modulating signal.My questions are:1.- The recording current is ok? (Around 1mA to 2mA)?2.- The recoding bias level should be increased or decreased?3.- How I can determine the best bias frequency for the heads?Best regards

author: ElektroQuark
author_rank: Unknown
timestamp: June 17, 2023, 06:40:21 pm
content: Ask here:tapeheads.net

author: e.sotillet
author_rank: Contributor
timestamp: July 08, 2023, 03:23:54 pm
content: I post the question on the tapehead forum but no response yet. I will try to modify the bias frequency or the output capability of the driver opamp.Best regards

author: Vovk_Z
author_rank: Super Contributor
timestamp: July 10, 2023, 08:47:48 am
content: I'm bad familiar with a tape recording (and haven't done anything like that more than 20 years) but one of the ways to find an optimal magnetising current is to set it so you have the same output voltage level at 400 Hz and 10 kHz. After that you may vary it more to find a point with smaller nonlinearity (or higher tape linearity).
Cassette Tape Data Storage PCB project build files are now available - Page 1
Forum section: electronics / projects

author: Ccandrews
author_rank: Contributor
timestamp: March 30, 2020, 01:50:55 am
content: The gerber build files for the SBC-85 Single Board Computer cassette tape interface are available for download. While this board can use the SID and SOD signals from the SBC-85 backplane, it primarily uses the digital I/O header for connection to any type of microcomputer or interface (TTL). Information on the project is onHackaday.ioand the user manual, gerber build files, etc., is on theSBC-85.COMproject site. Example code is also available on the SBC-85 site.RegardsCraig
Castellated holes and high current battery pins - Page 1
Forum section: electronics / projects

author: OwenH
author_rank: Contributor
timestamp: October 04, 2022, 11:24:12 am
content: Hi,I'm working on a design with limited clearance from the edge of my power connection. This is a DC 24v design that uses small 3mm banana pins to transfer power from a battery. Peak current is about 20 amps (momentary) with the average current being slightly less than 10 amps. The banana pins screw into a receptacle that is built up into an electrical block made out of PEEK. The electrical routing needs to make two 90 degree turns and make it to a spring pin target header. In addition to the two banana pins there are five spring pins for data connections, but I'm not very concerned about them, considering they don't carry significant current. This whole assembly is mounted into an aluminium machined and anodised enclosure.The issue is that there is very limited clearance between the solder cup on the banana pin and the enclosure. The routing needs to make the two 90 degree turns very close to the receptacle and this limits my ability to directly solder and bend the wires. Hopefully the screen grabs help to illustrate the design.My thought was that maybe I could use a small PCB with castellated holes to make the 90 degree bend and then just solder wires from the PCB to get to the spring pin target header. The PCB would be screwed to the back of the PEEK connector block for additional support (the screw isn't shown in the screen grab). Not sure how good of an idea this is with high current, but I would be able to use at least 2oz copper on both the top and bottom layers. Does anyone have any experience with using a castellated hole to mount a pin? Could this be reliable?

author: NiHaoMike
author_rank: Super Contributor
timestamp: October 04, 2022, 01:07:14 pm
content: Doesn't look very mechanically robust to me. It looks like you can get wires into the ends if you bend the wires before soldering.
Cat 7 RJ45 Ethernet Cable for CAN-FD application - Page 1
Forum section: electronics / projects

author: Blackgar
author_rank: Contributor
timestamp: May 23, 2022, 10:16:41 am
content: On a application with CAN-FD, I want to use a Cat 7 cable with 30 AWG pure copper.I choose it since it has twisted pair cables and its shielded.I am not sure if the 30 AWG are enough. Could someone explain me?P.S I forgot to mention that the distance/length is 4-5m

author: fchk
author_rank: Frequent Contributor
timestamp: May 23, 2022, 12:40:08 pm
content: RJ45 is mentioned in CAN in Automation (CiA) Standard 303 Part 1. You really should use the standard pinout:1. CAN_H2. CAN_L3. CAN_GND (Signal Grould)4. (NC)5. (NC)6. Optional CAN Shield7. Optional Ground for 8.8. Optional external positive supply for transceivers, optocouplers etc. Should be between 18VDC to 30VDC with nominal 24VDC.30AWG should be enough given the length.
Cat Toy or RoboVac..Maybe I have the perfect tool to learn about Robotics! - Page 1
Forum section: electronics / projects

author: SuzyC
author_rank: Frequent Contributor
timestamp: July 01, 2019, 12:03:56 am
content: A friend also gave me a completely anonymous standard size robot vac. Absolutely no ID on it or model number or even a Made in GNW sticker! A sticker clearly identifies the 18V charger power supply voltage and current and says 35-Watt power when in use.I call this vac Moron, It had bad NIMH batteries which I replaced, and now I press the Auto button and it moves about the floor just like it should do when it is cleaning up everything, in an usual systematic semi-random way, but it doesn't turn on the cleaning brushes/roller brush or the Vac Fan.I've taken it apart, and no ID inside at all. Has one large PCB with a no p/n 64-pin flat-pac pinout MCU 8MHz clock xtal, and all the electronics on it, all of the PCB has a clear conformal coating and all the connectors to the multitude of sensors, motors, etc. have been epoxy-like glued so they cannot be unconnected. All the sensors seem to be working correctly, it bumbles away around the room just like the real thing and knows when it has come upon a stairway!It is a pretty sophisticated vacbot, no bumper switches, works with infrared sensors for almost everything except the dustbin inserted and wheel motors prolapse off-the-ground sensor both use microswitches. It even has an infrared sensor to detect if any large dirt particles have entered and change/interrupt the beam signal across the port to the dustbin.Also has a remote-control IRF lens on the top, but I have n o remote!Here is a chance to learn how to hack a bot!But this would mean that I would have to start out with a MCU from scratch, not a problem for me, but it would take me a few weeks to just teach it to dance! And then I would have to learn how to use the infrared sensors to detect stairways and collisions.Finally, I would have to develop an algorithm to clean the room.Right now, I have rubbed tuna fish oil and catnip on the top of it and the cats love to watch it move and play with it!.All in all, sounds like fun. I could build any kind of basic robot with this as a base, or just have fun learning how to design robots.What to do next?? Leave it to the cats or hack it?What would you do with something like this?
CAT6a, USB 3.0 and SFP Cable Eye Diagram Verification with Signal Analyzer - Page 1
Forum section: electronics / projects

author: batteksystem
author_rank: Regular Contributor
timestamp: December 01, 2021, 11:15:36 am
content: I am quite new to high frequency design and currently need to verify the performance on some cables and devices used in data center, like CAT6a 8p8c (833MHz Baud Rate), USB 3.0 (5Gbps), 100G QSFP (25Gbps) per lane.I am wondering if there are any cheap Chinese scope (Rigol come to my mind) that can help me verify the eye diagram?Thanks.

author: Terry Bites
author_rank: Super Contributor
timestamp: December 01, 2021, 01:56:24 pm
content: At these speeds you need a serious scope with high speed and complex triiger facilties. You need to spend at least $5k or get lucky on ebay.I'd be thinking Anritsu.
Catalex MP3 Player interfacing with Pic Chip - Page 1
Forum section: electronics / projects

author: andybarrett1
author_rank: Regular Contributor
timestamp: February 23, 2018, 10:46:13 am
content: Hi thank you for reading :-I have a project in mind using a Catalex MP3 playerhttp://geekmatic.in.ua/pdf/Catalex_MP3_board.pdfAm wondering if anyone here has had experience of using same or similar ....I need buttons (relay outputs) 1-16 to play tracks 1-16 with a possible stop and resetAny help welcomeBRAndy

author: David_AVD
author_rank: Super Contributor
timestamp: February 23, 2018, 10:02:25 pm
content: I played with that module a while back and did a smallwrite-up.
Cavity wavemeter design - Page 1
Forum section: electronics / projects

author: ChristofferB
author_rank: Frequent Contributor
timestamp: December 06, 2014, 07:08:04 pm
content: Being a ham, and looking into microwave design, I am trying to build up a set of test gear for the 10GHz(3cm) band. Turns out that frequency counters in that frequency range can get a bit (!) pricey, so the best option for measuring frequency is still a wavemeter and power detector.I know the classic HP waveguide-flanged wavemeters go for reasonable prices on Ebay and similar places, but I've decided to build it myself.These wavemeters basically consists of a lenght of waveguide, with a hole drilled in it, and on top of that, a metal(copper or brass, usually) tube is soldered to it, acting as a tunable cavity.In the lid of the can is a plunger, that can be screwed in or out, adjusting the resonant frequency of the cavity.I found an old article describing something like this, which is great, except I have completely given up on finding copper pipe in those, about 3-4 cm diameter dimensions.The question is this: If you need to calibrate an apparatus like the aforementioned with a known frequency source anyway; wouldn't the dimensions of thecavity tube be almost irrelevant? As long as it is somewhat close to the desired band, and you have a wide tuning range?Thanks in advance!-Christoffer

author: sca
author_rank: Regular Contributor
timestamp: December 07, 2014, 12:00:15 am
content: If you have any model engineers (ie steam engine makers) in your area, they will know where to get copper tube in larger sizes and small quantities.sca

author: Vgkid
author_rank: Super Contributor
timestamp: December 07, 2014, 01:04:07 am
content: here are a few divider chips: hittite microwavehttps://www.hittite.com/products/index.html/category/258

author: TerraHertz
author_rank: Super Contributor
timestamp: December 07, 2014, 01:11:27 am
content: You know you'll have to silver (or gold) plate the copper tube, right? The plunger must make good contact at the sliding point. Fine spring fingers and silver/gold plating is a must.I know it's fun to make stuff yourself, but really, why not buy a good resonator frequency meter of two anyway? You're right, they can be very cheap. Plus once you've seen the precision engineering involved, maybe you'll be less enthusiastic about attempting to make one. Would save you a lot of time, not re-inventing wheels.
CB/HAM/Microphone circular connectors part number? - Page 1
Forum section: electronics / projects

author: poorchava
author_rank: Super Contributor
timestamp: November 15, 2013, 01:24:14 pm
content: I think everyone knows, what type of connector I'm talking about. Circular type, from 2 up to >10 pins, secured with a nut. It's widely used to connect microphones to CB radios, as a soldering iron connector in Xytronic soldering equipment and probably in many more places. Looks like this:https://www.google.pl/search?q=cb+radio+microphone+connector&source=lnms&tbm=isch&sa=X&ei=Zx-GUprVNMOBhQe-74H4Aw&ved=0CAkQ_AUoAQ&biw=1440&bih=725Radioshack items 274-001 and 274-002I can obviously get that from ebay, but in this case I need a part from reputable manufacturer like Amphenol, Molex, Lemo, Tyco etc. Does anyone know the part number or family name for those connectors from a reputable supplier? The customer wants the connector to be very good quality, but at the same time it has to be compatible with those "CB radio mic connectors" because of existing stuff that people may connect to the device.

author: qno
author_rank: Frequent Contributor
timestamp: November 15, 2013, 08:35:03 pm
content: These connectors are not made by any reputable manufacturer.They are made in Taiwan.They are quite robust though.I have used them in the past.What is the application??

author: Rory
author_rank: Frequent Contributor
timestamp: November 15, 2013, 08:50:40 pm
content: These have been traditionally called Philmore plugs, and the mfr has been around a very long time.http://www.calcentron.com/Pages/philmore/philmore_multi-pin_mobile_connectors.php

author: Jon Chandler
author_rank: Frequent Contributor
timestamp: November 15, 2013, 09:55:06 pm
content: The source posted above is the only one I could find when I needed a 2-pin version for my solder paste dispenser.

author: JackOfVA
author_rank: Unknown
timestamp: November 15, 2013, 09:59:55 pm
content: Sometimes called "Kenwood" plugs because Kenwood ham radio gear uses them, but that's not the real origin of the connector.I buy mine from The RFSource in Gaithersberg Maryland -http://www.therfc.com/micconn.htm-- scroll to the bottom of the page.They will export ship for sales outside the USA.Jack

author: G7PSK
author_rank: Super Contributor
timestamp: November 16, 2013, 10:37:52 am
content: I used to use them for electrical control of hydraulic tipping gear on trailers some years ago they were just called multiway connectors, I got them from maplins and never had one fail although the operators of these trailers managed to break just about every thing else from the switch box, cables to the axles of the trailer I never had a connector failure despite it never having been designed for this type of use. Maplins still stock them.http://www.maplin.co.uk/buy-cables-and-connectors/connectors/multiway-connectors

author: madires
author_rank: Super Contributor
timestamp: November 17, 2013, 03:31:19 pm
content: And another well known online shop with 4 up to 8 pin connectors (sockets and plugs):www.reichelt.de/Mikrofonverbinder-fuer-Funkgeraete/2//index.html?ACTION=2&GROUPID=5189&LANGUAGE=EN
cc cv laser driver - Page 1
Forum section: electronics / projects

author: quadzillatech
author_rank: Contributor
timestamp: March 06, 2019, 01:13:08 am
content: Hi all,im building a 2 watt laser engraver for my cnc mill,its a 450nm laser diode,max voltage is 4.8v and it needs 1400ma ,im planing on using one 317 as a voltage regulator feeding a 2nd 317 as a current regulator,any reason why it shouldnt work,also as the 317 ref voltage is 1.25v i assume the first 317 will have to output 6.25v to the 2nd 317,im i right in thinking that?,also it can handle 1800ma puled,i againe assume it means pwn the power to it,if so any idea what frequency it should be,the diode is a nichia m-140,thanks in advance Paul m3-vuv.

author: unitedatoms
author_rank: Frequent Contributor
timestamp: March 06, 2019, 02:12:42 am
content: You can test the voltages, currents regulation in LTSpice, replace laser diode with resistor. So the calculations will prove correct for constant output. However the constant work mode will overheat the laser.May be in engraving it is more advantageous to create impacts by peak power rather than average power.It looks that people use high pulsing frequencies, higher than LM317 will handle.For PWM you may want to go several kHz with energy say of 0.1 milliJoules of output energy per pulse. Say 10KHz will average at 1W. Also the PWM needs to be constant width, due to energy per pulse, and frequency to be fixed or variable.So practical engraving circuit turns complicated quickly.
CC Debugger clone - Page 1
Forum section: electronics / projects

author: delicado
author_rank: Contributor
timestamp: October 04, 2015, 10:46:15 pm
content: HiDoes anyone know how reliable CC Debugger clones typically are? They're quite a bit cheaper than TI's, of course.On eBay, they're just around £7:http://www.ebay.co.uk/itm/Bluetooth-Emulator-CC-Debugger-For-Zigbee-Support-2540-2541-2530-Protocol-BH-/301742246401?hash=item46413d4a01Cheers

author: ruffy91
author_rank: Regular Contributor
timestamp: October 05, 2015, 04:38:58 am
content: I have 3 of those and they just work like the original:http://vi.raptor.ebaydesc.com/ws/eBayISAPI.dll?ViewItemDescV4&item=251219519218&category=4661&pm=1&ds=0&t=1444019795489I think when i bought them the 10$ clones didn't exist.
CC-Load, Again - Page 1
Forum section: electronics / projects

author: Thor-Arne
author_rank: Unknown
timestamp: February 14, 2013, 12:41:02 am
content: I've made Dave's CC-Load to.First "slam together" ending with it osculating the load... Between 80 kHz and 190 kHz.I guess I should read a bit more before putting it together, as I hadno caps in there at all.Oh, well... That was the night-time version:pSo I skimmed through the various implementations discussed all over the forum and I ended up with the attached schematic, based on Jay_Diddys suggestions. This has been tested with a couple relative low power psu's, 1.5A@5V and 2A@12V. more testing when I finally get that lab-psu finishedThe whole ting is mounted on a CPU heatsink with a fan, and I use 12V supply for it.So far, so good. Some more testing, and I might expand it with a uC and display.EDIT: Fixed schematic.

author: slashguitar
author_rank: Contributor
timestamp: February 14, 2013, 01:16:12 pm
content: Why did you connect the inverting inputs of the op-amps together?

author: Thor-Arne
author_rank: Unknown
timestamp: February 14, 2013, 01:41:43 pm
content: Doh, I didn't.....I just made that scematic from a cribble I did on paper, guess I didn't pay enough attention to what I was doing.Thanks for pointing that out.It's fixed now.
CC or CV power supply for an induction heater? - Page 1
Forum section: electronics / projects

author: drummerdimitri
author_rank: Frequent Contributor
timestamp: December 28, 2024, 05:51:09 pm
content: I bought a 1000W 20A 48V DC induction heater from Aliexpress and need to buy a power supply for the unit.Would I be better off with a CC or CV design? I'm afraid that a CV unit might get overloaded if a very large piece of steel is inserted into the coil and a CC unit would just limit the power output and not trip the power supply.That being said, I know that these units need to get 48V immediately and not a slow voltage ramp up since it needs a kick to get them to start oscillating.Either way, I will be installing a switch on one of the wires so that I can give the power supply time to get to the appropriate voltage before turning the unit on.What are your thoughts on this?

author: Vovk_Z
author_rank: Super Contributor
timestamp: December 31, 2024, 10:06:13 pm
content: I'm nor well known with induction heaters but unlikely it needs to be CC powered.
CC2510 Anyone? - Page 1
Forum section: electronics / projects

author: hithesh123
author_rank: Contributor
timestamp: June 12, 2013, 03:42:11 pm
content: Need some help getting started with CC2510. I am not using simpliciTI. Just a simple code for receiving RF packet.The code is not working. I am transmitting a pkt using smartRF studio. But nothing happens on the receiver.Here's the code. The RFTXRXIF is never set.I am using the CC2510 mini dev kit.Code://Clock config. Xtal osc,CLKCON = 0x80; //Main clk = OSC(26MHz) .Timer is HS OSC div by 128//END//**************RADIO CONFIG***************//RFTXRXIF=0; // clear RF int FlagRFST=0X00; // SFSTXON - Enable and calibrate freq synthesizer//while (MARCSTATE !=0x01); //wait till Radio enters IDLE modeRFST =0X02; // Radio in Receive Mode//while (MARCSTATE !=0x0D); //Wait or Radio to enter RX modewhile(1){if (RFTXRXIF) // interrupt{bcount_buff= RFD;RFTXRXIF=0; // reset interruptP1_1= 1; // RED LED ON- indicates int occurreddelay(); //LED stays ON for a whileP1_1 =0;RFST=0x04; // Radio Enters idle mode}if (tcount>1 && bcount_buff>0){for(i=0;i<bcount_buff;i++) //Blink GRN LED. # of Blinks=# of button presses{P1_0=1;delay();delay();P1_0=0;}}}}Here's the RF register settings -Code:PKTLEN = 0x05; // packet lengthPKTCTRL1 = 0x05; // packet automation controlPKTCTRL0 = 0x04; // packet automation controlADDR = 0x11; // device addressCHANNR = 0x00; // channel numberFSCTRL1 = 0x0A; // frequency synthesizer controlFREQ2 = 0x5D; // frequency control word, high byteFREQ1 = 0x93; // frequency control word, middle byteFREQ0 = 0xB1; // frequency control word, low byteMDMCFG4 = 0x86; // modem configurationMDMCFG3 = 0x83; // modem configurationMDMCFG2 = 0x03; // modem configurationDEVIATN = 0x44; // modem deviation settingMCSM0 = 0x14; // main radio control state machine configurationFOCCFG = 0x16; // frequency offset compensation configurationFSCAL1 = 0x00; // frequency synthesizer calibrationFSCAL0 = 0x11; // frequency synthesizer calibrationTEST1 = 0x31; // various test settingsTEST0 = 0x09; // various test settingsPA_TABLE0 = 0xFE; // pa power settingIOCFG2 = 0x2E; // radio test signal configuration (p1_7)
CC2530 - Page 1
Forum section: electronics / projects

author: Spekkio
author_rank: Regular Contributor
timestamp: September 01, 2011, 06:20:19 am
content: Hi!I have been trying build my own programmer for TI's CC2530. I cannot simply afford the dev-kits.I can probably never afford IAR that is needed for programming, but I thought it would be fun to try and write programs for it in SDCC. since it has a 8051 CPU.But it seems really hard to build a programmer.I have done the PCB according to the reference design you can find on TI's website. So I guess that I have set up up the chip correctly.I have connected pins P.2.2 and P2.1 to some digital IO's on a PIC. These two pins are needed for programming, they don't seem to use any standard like SPI, but a "SPI-like" interface.It is described in Users Guide and Datasheet how to time the signals to these pins.has anyone ever done something similar or worked with CC2530 before in this way?I want to use it for a ultra tiny wireless temperature sensor. I found that AVR has a MCU with built in IEEE 802.15.4, ATmega128RFA1. But it's too big.Are there any other MCU's with built in RF transceivers ?

author: joelby
author_rank: Frequent Contributor
timestamp: September 01, 2011, 06:29:38 am
content: Most things are only "SPI-like", so don't be afraid to bit-bang pins if you can't get the PIC's SPI peripheral to do exactly what you want. You should be able to find some examples of this to get you started (it looks like there might be one athttp://www.gedanken.demon.co.uk/amb-pic-code/, for example).

author: 74HC04
author_rank: Contributor
timestamp: September 01, 2011, 09:13:18 am
content: I've sucessfully used a GoodFET (http://goodfet.sourceforge.net/) with the CC1111 and CC1110 ICs. I can't see why it wouldn't work with the CC2530 but it may be worth dropping the designer an email if you're interested.

author: Spekkio
author_rank: Regular Contributor
timestamp: September 01, 2011, 10:14:08 am
content: Thanks

author: freker
author_rank: Newbie
timestamp: March 08, 2013, 06:29:51 am
content: Hi Spekkio,I realize this is an old thread, but I just wanted to hear if you were successful in programming the CC2530?Cheers

author: amyk
author_rank: Super Contributor
timestamp: March 08, 2013, 06:49:55 am
content: You can look for the "CC253x Flash Programming Guide". It's on TI's forums somewhere.