hybridfree/eevblog-posts huggingface dataset:
Old linear actuator problems starting up - Page 1
Forum section: electronics / projects

author: step_s
author_rank: Regular Contributor
timestamp: February 08, 2018, 08:34:56 pm
content: Hi guys.I recently got a hold of a couple of old 240V AC linear actuators and wanted to test out their lifting strength.My setup is quite simple (See picture 1). I just have the actuator hanging with some weights on the other end, to see how much it will lift.The issue is now that the actuator wont start running unless the load is around <5 kg, OR as I have done to test, I let the piston axle spin around ½ a rotation to get it going (it's obviously a snaildrive piston that will rotate if not fixed). When the actuator is started it will lift 25kg with ease, which is why I'm confused.The two directions are run by a simple BTA12-600 TRIAC with a 5k resistor from T2 to Gate, on each of the directional coils, kept on by an alligator clip (See picture 2, sorry for the messy setup). Ofcourse one at a time, depending on direction.My question is now, if this is normal, or if I need to do something else?TRIACshttp://www.st.com/content/ccc/resource/technical/document/datasheet/aa/8c/87/f6/18/fc/46/93/CD00002267.pdf/files/CD00002267.pdf/jcr:content/translations/en.CD00002267.pdf

author: Benta
author_rank: Super Contributor
timestamp: February 08, 2018, 08:48:28 pm
content: Looks to me like an AC induction motor. The starting torque is less than working rpm torque, so I don't wonder at your starting problems.No way to get around this, just accept that they are rated a 5 kg max.

author: CatalinaWOW
author_rank: Super Contributor
timestamp: February 11, 2018, 02:41:37 am
content: I fundamentally agree with Benta, with one small bit of wiggle room. These motors usually have a startup feature involving a capacitor to somewhat shift the input phase to simulate a second power phase. I believe that this is the component in the top left of your picture. If that capacitor has partially failed it will result in less phase shift and even lower starting torque. You may be able to improve your results by replacing the capacitor. I wouldn't expect much out of this, but if you need only a little more you might get there.
OLD METRIX 742C - Page 1
Forum section: electronics / projects

author: Kidon
author_rank: Regular Contributor
timestamp: May 24, 2020, 09:41:46 pm
content: Hi,Some time ago I picked up this 60’s METRIC 742C for cheap at a yard sale (before the confinement).It’s a very neat piece of equipment. However, it was missing the AC probe. So today I finally took the time to build oneAccording to the schematic. It’s using a 6AL5 double diode detector tube. Fortunately I had a few lying around.It’s not pretty, but it works great.
old nuclear reactors - Page 1
Forum section: electronics / projects

author: m3vuv
author_rank: Super Contributor
timestamp: September 01, 2021, 11:58:45 pm
content: just a quicky,are there any snaptran reactors still in operation ?

author: I wanted a rude username
author_rank: Frequent Contributor
timestamp: September 02, 2021, 04:23:00 am
content: No, all three were used only briefly. I don't think any ofthe SNAP systemsare still in use, although many of the spaceborne ones stillexist, most notably the famousSNAP-10A, which is of the reactor type.
OLD project Spectrum Analyzer Elektor OCT 2008 - Page 1
Forum section: electronics / projects

author: GGMM
author_rank: Frequent Contributor
timestamp: May 28, 2022, 04:22:43 pm
content: Hello,This is an old Elektor project from 2008.It’s a spectrum analyzer that works with a PC.Did either of you realize that?https://www.elektormagazine.com/magazine/elektor-200810/18924Before starting anything, the HEX 040360-W file is missing on the site to program the ATMega 8535.If anyone have it, he can download it.By being broader, I’m actually looking to build an analyzer. I am tolerant on the maximum frequency, because it is for shortwave radio. So even 100Mhz max can suit.In particular, I’m looking for something that works on PC, at worst with an oscilloscope.Thank you for your answerscdt

author: DavidAlfa
author_rank: Super Contributor
timestamp: May 28, 2022, 05:15:23 pm
content: From thepdf article:QuoteSo you had to buy the atmega from them.

author: GGMM
author_rank: Frequent Contributor
timestamp: June 16, 2022, 05:01:46 pm
content: Hello,Someone has already done this project in the past and would have the HEX file?? Elektor support does not find it.In fact, I want to make what simple thing for some HF measurements. (Radio)]A system with connection on oscilloscope suits me perfectly, (I found some diagrams), but not much with connexion on PC except the Elektor model.If you have links on this, knowing that 100MHZ is enough for me.here some simple interristings homebrew like i want. (For examples)https://www.qsl.net/va3iul/Homebrew_RF_Circuit_Design_Ideas/Homebrew_RF_Circuit_Design_Ideas.htm#Spectrum%20AnalyzersCdt

author: rstofer
author_rank: Super Contributor
timestamp: June 17, 2022, 03:26:30 pm
content: If you could live with 50 MHz, the Digilent Analog Discovery 2 can handle it. You can download the Waveforms software and play with a demo device to get a feel for the operation.https://digilent.com/shop/analog-discovery-2-100ms-s-usb-oscilloscope-logic-analyzer-and-variable-power-supply/That little box has a lot of capability.
Old RF semiconductors? - Page 1
Forum section: electronics / projects

author: mr ed
author_rank: Regular Contributor
timestamp: November 05, 2022, 02:16:56 am
content: I am beginning to think that some rf semiconductor devices get weak as they age. I'm talking about 100k hours of service old. Supplies are right on and match a DC ref chip) The reason is, as I try to repair a rohde and schwarz SMIQ, I see some mmics with lower gain than expected. I have found dead rf devices (a fet and 2 mmics so far) but I seem to have low gains in some related circuits. I don't know what's going on here? Replacing one mmic amp, I get a bit more db of rf (only running at 300Mhz). This repair has been a real grind.Am I mistaken?
Old Ricoh printer reusing the lcd - Page 1
Forum section: electronics / projects

author: no_name03
author_rank: Newbie
timestamp: January 17, 2025, 03:50:25 pm
content: Hi there, I would like to reuse the electronic components of and old Ricoh Aficio MP C2031, more specifically the screen, which is and LCD (640x200) labeled SHARP, with part number LM089HB1T02. I was unable to find any datasheet on the device, so I have no idea how to use this device. It has a flex cable with 17 pins and 2 wire cable for power (most probably). I'd like to use also the other components (some RICOH labeled chips there, for example MB87F4192), for which I also couldn't find any datasheets. Any help would be appreciated.

author: DavidAlfa
author_rank: Super Contributor
timestamp: January 17, 2025, 05:36:17 pm
content: https://www.elektroda.pl/rtvforum/topic2686696.html
Old Scanner type? - Page 1
Forum section: electronics / projects

author: Chris56000
author_rank: Frequent Contributor
timestamp: January 28, 2019, 07:00:21 pm
content: Hi!Just a quickie one - I know it's only a minor point - I'd like to build this UV LED exposure box. . .https://lytrax.io/blog/projects/diy-uv-exposure-box. . .but it would be handy to have the same or a very similar scanner as a base as the model depicted already has 12V and USB inlets ready for use and two buttons on the front in a convenient place all ready for use!Does anyone recognize this make and model of scanner so I can look for the same or one very similar?Chris Williams

author: rsjsouza
author_rank: Super Contributor
timestamp: January 28, 2019, 07:11:43 pm
content: This one?http://www.itholix.com/products/128-hp-scanjet-g2410-flatbed-scanner-l2694a.aspx

author: webgiorgio
author_rank: Regular Contributor
timestamp: January 29, 2019, 12:34:07 pm
content: Any old scanner will work.Here is minehttp://www.ingdemurtas.it/elettronica/bromografo2/

author: Chris56000
author_rank: Frequent Contributor
timestamp: February 25, 2019, 07:23:46 pm
content: Hi!Thanks for that – the reason I was interested in the same model as per the original prototype as it already has USB and power holes provided to give a neat completed finish plus a convenient sloping front for the display module, control buttons & encoder control!Chris Williams
Old school LED display for my hobby CNC mill - Page 1
Forum section: electronics / projects

author: homebrew
author_rank: Frequent Contributor
timestamp: June 04, 2015, 07:55:34 pm
content: Just wanted to share a project I did for fun during the last weeks.I really like those old school 7 segment LED display so I wanted to built a little XYZ coordinate display for my CNC mill.So I decided to not only use 80's display technology but also to do the rest of the project in 80's style:* 74HC573 latches* UDN2585 transistor array* RS232 link to computer* (ATTiny2313 - ok, not so much from the 80's)Of course everything on veroboard connected with enameled copper wire ... But hey, it works!If you are interested in the design-files (cad/firmware/source-code for emc) or more detailled description then go to:http://www.open-instruments.ch/But as I'm just a hobbyist I'm looking forward to any sort of feedback! Maybe you would have approached this completely different ...Have fun!
Old SD micro to MMC board - Page 1
Forum section: electronics / projects

author: hichm19956
author_rank: Newbie
timestamp: October 26, 2019, 12:13:04 pm
content: Hello,it's first time that i use kicad to draw pcb not circuit,i find the pinout of MMC card thereUntangle the web of removable storagethen i try to do conversion between SD midro card 8-pin MMC card mobile 13-pin .i attached my pcb shema here, i want your opinion to see if it will work or not.

author: Rerouter
author_rank: Super Contributor
timestamp: October 26, 2019, 12:27:24 pm
content: Afraid that what you attached will not really work for others, the current version of Kicad does not embed footprints in the .pcb file,Instead on the main kicad program screen, up the top the icon of a shipping box, archive the project then it will all be includedRight now its traces, a few pads with no net name, and a missing footprint.
Old Tektronix connector - Page 1
Forum section: electronics / projects

author: EV
author_rank: Frequent Contributor
timestamp: November 20, 2013, 08:00:28 am
content: Where can I find a female connector for the male connector in the picture?

author: david77
author_rank: Frequent Contributor
timestamp: November 20, 2013, 08:27:55 am
content: Quote from: EV on November 20, 2013, 08:00:28 amThat looks like a standard US mains plug. I'd say a trailing socket from a US extension cord should fit. Where in Europe you might get such a thing is another matter.

author: uoficowboy
author_rank: Regular Contributor
timestamp: November 21, 2013, 03:47:33 pm
content: Quote from: david77 on November 20, 2013, 08:27:55 amMy understanding is that the Teks used a standard US plug there. So most extension cords will fit in. Except - you have to reduce the extension cord's socket's outer diameter so that it'll fit in - you can just take a knife to one and remove the extra material.

author: EV
author_rank: Frequent Contributor
timestamp: November 21, 2013, 09:04:14 pm
content: Thaks for replies!I have ordered one like in this link:http://www.ebay.co.uk/itm/350913051163?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1497.l2649It is only for 125 V, but try it.

author: Stonent
author_rank: Super Contributor
timestamp: November 23, 2013, 06:37:53 am
content: Just on the off chance that someone is working with adapting a US plug to something else. Keep this in mind. (In order to stay safe as possible)If the male plug has a sideways blade on your right (holding the plug facing you), it is meant for a 20 Amp socket. If the female end has the T shape on the left, it is 20 Amp rated but can accept a 15 Amp plug as well.And here's the others.

author: VintageTekFan
author_rank: Regular Contributor
timestamp: November 25, 2013, 03:00:46 pm
content: Quote from: Stonent on November 23, 2013, 06:37:53 amNice chart!

author: Stonent
author_rank: Super Contributor
timestamp: November 25, 2013, 09:05:00 pm
content: Quote from: VintageTekFan on November 25, 2013, 03:00:46 pmYou can thank Wikipedia.
Old Thomas and Betts IDC connector - Page 1
Forum section: electronics / projects

author: dorkshoei
author_rank: Frequent Contributor
timestamp: December 15, 2017, 05:31:09 pm
content: Posting here as folks have been pretty good in past at ID'ing connectors.This is from a fairly valuable piece of 1990s Fluke test equipment that I'd like to keep original. The IDC connector is stamped "T&B/Ansley" and the handle is stamped T&B. I reached out to Thomas and Betts and they said the design was sold to TE Connectivity and they've not made it in 15 years. TE doesn't recognize it.It's different from the current IDC connectors which have holes on the edges where the optional strain relief fits into. On the T&B the handle portion looks like it snaps onto the sides and has gone missing on one.I'm looking for the part# for this handle, or at least if there is an standard term for it that I can use to try and find a surplus one.I'm aware I could remove, crimp a new IDC connector onto it with a strain relief and a loop but as I said, I'd prefer to keep it original. That said, I do need functional as right now I'm having to pull on the cables to remove/pry off with screwdriver which isn't ideal.Thanks
OLD TLA704 - TLA7AA4 - TLA7N4 questions - Page 1
Forum section: electronics / projects

author: rfdes
author_rank: Regular Contributor
timestamp: January 16, 2023, 06:58:47 pm
content: Hoping someone might know how to accomplish the following:I use an old 704 analyzer LAN connected to my PC running TLA version 6.1. My principal LA module is the TLA7AA4. However I only own a single cable with flying leads. Recently I have need for 32 channels for a debug project. Not wanting to purchase more cables and flying lead adapters, I want to put into service a good working TLA7N4 module where I have all of the cables/leads. I just realized that Ver 6.1 of the TLA app no longer recognizes this 7N4 modules.Short of downgrading to Ver 5.1, is there a way to trick Ver 6.1 to 'see' the 7N4 module? I thought maybe there might be a registry patch, etc. that would allow the unit to work with this module. I guess it is not a biggy to downgrade, do my thing, and then upgrade again. I'm just looking for an easy way to get across the goal line...ThanksJim

author: rfdes
author_rank: Regular Contributor
timestamp: January 19, 2023, 05:01:55 pm
content: Hi -Thanks for the response.Reading the 'Release Notes' for Ver 6, they note that the older modules are no longer supported.7. No longer supports the following modules/systems, which are beyond LongTerm Product Support:TLA7Lx/Mx/Nx/Px/QxTLA7Dx/ExTLA704/714/715/711/720/721I took that to mean that the software would simply ignore the older modules.So, I am not sure if that is totally true or not. Possibly someone else that has an older module running under Ver 6.x can verify that is true.I will run the firmware loader to check and see what it reports.Thanks again - Jim

author: avics
author_rank: Newbie
timestamp: February 06, 2023, 08:12:47 pm
content: You could use V5.8 as well. This one will recognize the old modules.

author: dxl
author_rank: Regular Contributor
timestamp: February 06, 2023, 08:19:44 pm
content: I have TLA5.1 running on my TLA7012 with a TLA7P4 and a TL7AA4. So if you have no real need for the changed UI, you could just switch to 5.1. My experience is that this is the most stable version. I encountered quite some bugs in the later (>= 5.6) version when using a TLA7BB4 module. I finally sold the TLA7BB4 just because 5.1 doesn't support it.

author: calibrationfixture
author_rank: Regular Contributor
timestamp: February 09, 2023, 08:51:42 am
content: Hi dxl,@ « Reply #4:I posted a request on your Tektronix MSO70404 SPC Failure Topic regarding the Python Option enabling Program. I don't have a MSO70K Instrument, but the Program shows some anomalies with TDS5000B Instruments. Maybe also for MSO70K Series.Greetings,Calibrationfixture
old VTVM (vacuum tube volt meter)? - Page 1
Forum section: electronics / projects

author: heathkitman
author_rank: Contributor
timestamp: June 05, 2013, 12:35:36 pm
content: Hi all:One of the first pieces of test equipment that I built over 45 years ago was a Heathkit IM-18 VTVM. I keep it on my bench now just to remind me of the good old days. I have always wondered why old VTVM (vacuum tube volt meter) use a 1.5 volt battery to make ohm measurements. My Dad's old meter was destroyed when I forgot and left the D cell in it and the acid leeched out.I am thinking about using a small bridge rectifier and a LM317 to replace the battery. Is there any reason why this will not work?I have attached a link of the schematichttp://www.heathkit.nu/IM-18_schema_1024.gifThanks

author: SLJ
author_rank: Frequent Contributor
timestamp: June 05, 2013, 01:44:55 pm
content: Should work. Here's a circuit:http://mikeyancey.com/VTVM_battery_eliminator.phpRun it off the 6.3 V filament tap.

author: heathkitman
author_rank: Contributor
timestamp: June 05, 2013, 04:33:45 pm
content: Thank you. That is exactly what I was looking for. I wonder why it was designed with a battery in the first place. Cost of components? Before the advent of devices like the LM317 it was not a simple task to accomplish the V regulation. Is it necessary that C5 be Tantalum?

author: SLJ
author_rank: Frequent Contributor
timestamp: June 05, 2013, 05:37:33 pm
content: I think that's exactly it. No voltage regulation needed with a battery. Just a control to adjust the voltage to zero the ohms scale.

author: Paul Price
author_rank: Super Contributor
timestamp: June 05, 2013, 10:47:04 pm
content: I built one of these for a Heathkit V7A. All the electorlytic capacitors and the power MOSFET were pulled off a defunct PC motherboard that are always present near close to the CPU power supply section of the motherboard.The 4 1N4001 diodes protect against connecting the VTVM probe to a live circuit. If you dpn't ever think you will make that mistake, you don't need them.If you don't want to pull a N-Chan MOSFET from a motherboard, any 1W medium power high beta NPN transistor will substitute.Cheaper than a LM317 circuit and simpler to build if you can find any op-amp laying around.And, unlike any other circuit, this one is fool-proof and nothing, no high voltage could kill anything in this battery circuit with any accident with the meter's probing around looking for ohms in all the volt places.
Old Z8671- & P8052-BASIC MCUs - Page 1
Forum section: electronics / projects

author: matseng
author_rank: Frequent Contributor
timestamp: December 30, 2015, 04:20:25 am
content: While rummaging thru my old electronics junk boxes I found both a Zilog Z8671 and an Intel P8052 CPU/MCU. Both are kinda special since they have internal BASIC interpreters and can be programmed by just hooking up a terminal to them.The Zilog was made in August 1983 and the Intel in December 1984 so they are really ancient. I also got a bunch of contemporary SRAMS and other crap so I can hopefully get them running without any modern parts. I just need a real VT100 terminal and I'm set :-)I'll be using one of them for my entry in the Retrochallenge Competition, but not sure which one.http://www.wickensonline.co.uk/retrochallenge-2012sc/

author: retrolefty
author_rank: Super Contributor
timestamp: December 30, 2015, 07:04:55 pm
content: Cool. That 8052AH may be old but apparently still available for sale:http://www.micromint.com/products.html?id=97

author: ChristofferB
author_rank: Frequent Contributor
timestamp: December 30, 2015, 07:44:08 pm
content: Nice find!I've worked a bit with both. Apparently, you can get a FORTH version of the z8671..The 8052 has routines for writing basic and assembler programs directly to EPROM, which I found really neat.Note that when you establish serial to the 8052, the first character needs to be a "space" -it calculates the baudrate from that! I spent a loooot of time on debugging before i knew that...Looking forward to seeing what you come up with!--Christoffer

author: TheSteve
author_rank: Unknown
timestamp: October 30, 2016, 01:41:00 am
content: Did you happen to ever use the Z8671 and write code for it?I have an ancient(but cool) battery charger/discharger that uses the Z8671/Z8681/Z8691 CPU's with an external eprom and sram. I'd like to make a few changes to the program and would like to some help with it.I also have quite a few Z8681 "romless" CPU's in stock if anyone needs one.
Old - Page 1
Forum section: electronics / projects

author: variometer
author_rank: Newbie
timestamp: July 17, 2022, 04:58:08 pm
content: HelloDoes anyone know if Tektronix made an analog/crt 100 MHz, 2 channel scope that featured 500 uv vertical division (or better)Thanks

author: tooki
author_rank: Super Contributor
timestamp: July 17, 2022, 09:13:27 pm
content: Hi, and welcome!I don’t think this is going to invite many answers:1. I doubt you could have come up with a worse thread title if you tried. A title should be a summary of what’s inside. “Old” says literally nothing about your question. If it was written in error, note that as the thread starter, you can edit the post and with it, the title.2. The Test Equipment subforum would be a better match for this question than here (Projects, etc).

author: Jeff eelcr
author_rank: Frequent Contributor
timestamp: July 19, 2022, 01:44:19 am
content: The 2225 was the only one I remember with that spec and at nowherenear 100MHz.If any others it would be very hi end or custom.Jeff

author: niconiconi
author_rank: Frequent Contributor
timestamp: July 23, 2022, 01:17:23 am
content: Check Jim Williams' Application Notes. They contain encyclopedic information on electronics instrumentation and vintage oscilloscopes.AN70: A Monolithic Switching Regulator with 100μV Output Noisehttps://www.analog.com/media/en/technical-documentation/application-notes/an70.pdfAN124: 775 Nanovolt Noise Measurement for A Low Noise Voltage Referencehttps://www.analog.com/media/en/technical-documentation/application-notes/an124f.pdfThe answer is No. There is no Tektronix oscilloscope plug-in that measures down to microvolt with 100 MHz bandwidth. They only go to 1 MHz. Though, at 1mV, there are a few 100 MHz plug-ins.If you want high-bandwidth, low-level measurement, at least for power supplies, you can do what Jim Williams did - use a general-purpose wideband RF amplifier (he used an HP 461A, as listed), DC-block your input with a large capacitor (most RF DC blocks have a capacitance too small for low-frequency measurements, the HP 10240B DC block is an unusual one was a really huge capacitor inside, but I think it's not difficult to make your own) and proceeds with full 50-ohm instrumentation - RF amplifier + oscilloscope, or spectrum analyzer.

author: Neomys Sapiens
author_rank: Super Contributor
timestamp: July 23, 2022, 02:41:30 am
content: The Tektronix 454 analogue 150MHz scope seems to have a special mode that does at least come a bit closer.Citation from TekWiki:It is possible to cascade the channel-1 and channel-2 input amplifiers to obtain a sensitivity of 400 μV/div. In that configuration, the vertical bandwidth is 33 MHz.

author: Jeff eelcr
author_rank: Frequent Contributor
timestamp: July 24, 2022, 12:43:18 pm
content: I did notice that this could be done with some 2400 series DSOsand some other manufactures scopes.Jeff
Older 3M 724 Workstation Monitor - Page 1
Forum section: electronics / projects

author: trapc45
author_rank: Newbie
timestamp: February 23, 2018, 02:15:01 am
content: I have two scavenged 724 monitors that are 3M branded (pre SCS). I am not certain on the age of either, but one I am going ti guess is circa 2006. The both seem to function fine with the exception of the green LEDs that are supposed to illuminate when things are ok. Both units alarm correctly and the alarm LEDs illuminate for both high and low resistance. Any ideas what may be happening? At first I thought the older unit the LED may have died, but knowing the setup it was used in there was only one operator so the likely hood of both being dead is pretty slim. Especially on both units.
Oldies  MM  the German Crash Test  D I N57410  regulations - Page 1
Forum section: electronics / projects

author: Kiriakos-GR
author_rank: Super Contributor
timestamp: May 09, 2011, 02:06:30 am
content: According to this link (PDF to download )Every analog multimeter rated at 650V , it must pass the safety test of2000Vfor 60 seconds ,so to comply .Also , the ones that are rated above the 650V , they should pass the safety test of3000V50Hz for 60 seconds .I found the info about the D I N 57410 accidentally , on the Users manual of my analog MetraWatt MA-4S ,that it did had pass the 3KV test.And so I started to investigate about it , for more details.http://www.google.gr/url?sa=t&source=web&cd=7&ved=0CEAQFjAG&url=http%3A%2F%2Fwww.redur.de%2Fimg%2Fpdf%2Ftech_information.pdf&rct=j&q=DIN%2057410&ei=DjLHTd7-L4XrOZX8ye0B&usg=AFQjCNERqxduo2uX3vNZyRyhJFN4evf2nw&cad=rjaIt is sad by thinking that those days at 80s there was no youtube service and fast ADSL lines,or else we would had , videos with analog fireworks too .
OLED and TFT setup parameters - Page 1
Forum section: electronics / projects

author: MasRetta
author_rank: Newbie
timestamp: September 27, 2017, 02:43:06 pm
content: I have been searching the internet and forums for a tutorial on OLED and/or TFT displays that explains the effect of the different setup parameters found in the datasheets (for example: Gamma set, Color set, VCOM control, Positive and Negative Gamma correction, etc).Anyone that could point me at some good links?
OLED display interface - Page 1
Forum section: electronics / projects

author: LukeW
author_rank: Frequent Contributor
timestamp: October 30, 2014, 11:58:36 am
content: I'd appreciate a fresh set of eyes to check over this schematic for me before I commit it. Any bugs that I've missed? ThanksThis is driving an SSD1351 display module. Very similar to the Freetronics OLED interface module (https://github.com/freetronics/OLED128/blob/master/OLED128.pdf?raw=true) but I have made a few little changes.The regulated 3.3V rail is supplied externally, not shown on this schematic, and the on-board 3.3V LDO has been removed. I've changed the boost converter that generates the HV bias to a different device which is cheaper (FAN5331) but should still do an equivalent job and changed the component values surrounding the boost converter to suit. I've replaced the 4.7 uF 25V capacitor on pin 3 of the display with a ceramic instead of the tantalum, and the supply voltage to the boost converter is 3.3V and not 5V as it originally was.The digital control lines are connected to an AVR microcontroller operating at 3.3V (not shown on this schematic) and the buffer IC has been removed because logic level translation down to 3.3V isn't needed. We can assume 5V will never be applied, either on the input voltage rail or the digital inputs. I've removed the LEDs, pushbuttons and SD card, they're not needed, and I've removed the connections to both the GPIO pins on the SSD1351. I don't need the ability for the SSD1351 to turn off the boost converter, this saves one resistor, and we're not really concerned about highly optimized quiescent power consumption here. The boost converter enable line is always tied high.
OLED display issue - sides are a bit dimmer than the center... - Page 1
Forum section: electronics / projects

author: alank2
author_rank: Super Contributor
timestamp: June 14, 2016, 01:35:19 am
content: I am using a Newhaven NHD-3.12-25664UCY2 and it allows a 16 level gray scale/brightness levels.http://www.newhavendisplay.com/redirect.html?goto=www.newhavendisplay.com%2Fspecs%2FNHD-3.12-25664UMY3.pdf&action=urlIt uses a SSD1322 controller.I am using their stock example init code except that it has been modified for use on an AVR. The issue is that at lower grayscale levels, the left 32 pixels and right 32 pixels are noticeably dimmer than the center ones.Code://configure pinsDDRB|=_BV(SPI_RESET) | _BV(SPI_SS) | _BV(SPI_CMD_DATA) | _BV(SPI_SO) | _BV(SPI_CLK);PORTB|=_BV(SPI_SS);//configure spiSPCR|=_BV(SPE) | _BV(MSTR) /*| _BV(SPR0)*/;SPSR|=_BV(SPI2X);PORTB&=~_BV(SPI_RESET);Delay_ms(40);PORTB|=_BV(SPI_RESET);Delay_ms(10);Set_Command_Lock(0x12);// Unlock Basic Commands (0x12/0x16)Set_Display_On_Off(0x00);// Display Off (0x00/0x01)Set_Column_Address(0x1C,0x5B);Set_Row_Address(0x00,0x3F);Set_Display_Clock(0x91);// Set Clock as 80 Frames/SecSet_Multiplex_Ratio(0x3F);// 1/64 Duty (0x0F~0x3F)Set_Display_Offset(0x00);// Shift Mapping RAM Counter (0x00~0x3F)Set_Start_Line(0x00);// Set Mapping RAM Display Start Line (0x00~0x7F)Set_Remap_Format(0x14);// Set Horizontal Address Increment// Column Address 0 Mapped to SEG0// Disable Nibble Remap// Scan from COM[N-1] to COM0// Disable COM Split Odd Even// Enable Dual COM Line ModeSet_GPIO(0x00);// Disable GPIO Pins InputSet_Function_Selection(0x01);// Enable Internal VDD RegulatorSet_Display_Enhancement_A(0xA0,0xFD);// Enable External VSLSet_Contrast_Current(0x9F);// Set Segment Output CurrentSet_Master_Current(0x0f);// Set Scale Factor of Segment Output Current Control//Set_Gray_Scale_Table();// Set Pulse Width for Gray Scale TableSet_Linear_Gray_Scale_Table();//set default linear gray scale tableSet_Phase_Length(0xE2);// Set Phase 1 as 5 Clocks & Phase 2 as 14 ClocksSet_Display_Enhancement_B(0x20);// Enhance Driving Scheme Capability (0x00/0x20)Set_Precharge_Voltage(0x1F);// Set Pre-Charge Voltage Level as 0.60*VCCSet_Precharge_Period(0x08);// Set Second Pre-Charge Period as 8 ClocksSet_VCOMH(0x07);// Set Common Pins Deselect Voltage Level as 0.86*VCCSet_Display_Mode(0x02);// Normal Display Mode (0x00/0x01/0x02/0x03)Set_Partial_Display(0x01,0x00,0x00);// Disable Partial DisplaySet_Display_On_Off(0x01);Any thoughts on something I should try to tweak?
OLED/LCD noise on power supply? - Page 1
Forum section: electronics / projects

author: Martinn
author_rank: Frequent Contributor
timestamp: August 16, 2023, 01:56:01 pm
content: I am working on a sigrok oscilloscope frontend and as I try to push sensitivity, I am concerned about electrical noise interfering with the amplifier.The Stanford Research SR-560 (OK, quite a different league) has only LED indicators and even shuts down its processor completely when no user/remote interaction is active.I remember having read that particularly small OLED panelshttps://www.eevblog.com/forum/projects/oled-noise-on-power-rails/create electrical noise - which is not too surprising, as all displays need some higher internal drive voltages and are multiplexed, with power levels at OLED even higher than LCD (which are a pure capacitive load).As I probably won't be able to modify sigrok pulseview, I won't have a GUI to set frontend parameters (range, filter cutoff, coupling) so I might add a small UI, which could be a tiny graphical display (like one of those OLED modules) or a handful of LEDs which could be driven statically (generating no noise at all). Maybe the noise issue is not too significant as I both have the FX2LP USB processor and a DC/DC converter for isolation, but who knows.Besides the popular tiny OLEDshttps://www.adafruit.com/category/98LCD COB ones come to my mindhttps://www.lcd-module.com/produkte/dog.htmlDo you have any experience with electrical noise and display modules?

author: MarkF
author_rank: Super Contributor
timestamp: August 16, 2023, 05:44:04 pm
content: I have used two small OLED displays on three projects without any noise issues. At least nothing like what you linked to.But, noise is relative and your mileage my differ.I used three of the Adafruit'sOLED Breakout Board - 16-bit Color 1.27"5V compatible andone Waveshare1.5inch RGB OLED Display Module 128x128 Pixels 16-bit High Color (65K Colors)3v3 only.One of my projects using the Adafruit OLED was a 1Hz to 10MHz function generator based on the AD9834 chip.You can checkout some signal outputs and FFT captures atRe: Looking for <$50 function generator.All three of my projects used varies PIC Microcontrollers and 3-terminal regulators on the PCB.
OLIMEX MOD_GPS - interface voltage level? - Page 1
Forum section: electronics / projects

author: up8051
author_rank: Frequent Contributor
timestamp: March 18, 2020, 02:02:07 pm
content: Hello,I bought several MOD_GPS modules from Olimex from the Polish TME distributor.Module can be powered from 2.7V to 5V.But there no information about voltage level of TxD and RxD lines.The measured voltages on these lines are 3.3V.RxD with Pull-Up to 3.3V?I need to known if the RxD line is 5V tollerand.I sent e-mail to support@olimex.com but any respond.I make a topic on Olimex Support Forum but also any respond.I tried conntact via Facebook but they redirect me to suppot@olimex.comSo I have vicious circleFatal level of technical documentation and support.Maybe someone will help me get information about interface voltage level.Regards,up8051 aka JarekC.DIY

author: senso
author_rank: Frequent Contributor
timestamp: March 18, 2020, 06:06:26 pm
content: Its based on a uBlox (Neo) 7 module, that specifies a 3.6v Max voltage, so its safe to assume that it wont support/tolerate 5V on its pins..https://www.u-blox.com/en/product/neo-7-seriesAnd the UEXT connector also only talks about 3.3v, safe to assume that its 3.3v IO only.

author: up8051
author_rank: Frequent Contributor
timestamp: March 18, 2020, 08:11:45 pm
content: Thanks.This afternoon I received information from the distributor that there is no buffer between the connector and uBlox module,so pin RxD isnot5V tollerant
Omega Z33 quartz watch - Page 1
Forum section: electronics / projects

author: Wytnucls
author_rank: Super Contributor
timestamp: November 21, 2013, 04:53:53 am
content: Omega released an expensive pilot quartz watch last year with normal hands, but also an LCD display, which actually looks like a LED display. I wonder how this is achieved.With a red LED backlight probably, but I'm not sure how the reverse video effect is done with the LCD. Any thoughts?

author: SeanB
author_rank: Super Contributor
timestamp: November 21, 2013, 05:07:16 am
content: Simple to use a red filter on the LCD reflector and a phosphor coat on there to generate extra red light from the incoming blue or UV light to add extra red light to the display. Do not think a backlight will be used as then battery life will take a dramatic drop.

author: Wytnucls
author_rank: Super Contributor
timestamp: November 21, 2013, 06:53:30 am
content: Your explanation is possible, but the display needs to switched on with the push of a button, so red backlight is more probable, under a negative display. Is a negative display more power hungry than a positive one?In addition to the temperature-controlled crystal, power consumption could be quite high.

author: Wytnucls
author_rank: Super Contributor
timestamp: November 21, 2013, 07:03:15 am
content: Definitely comes with a red auto-adjust backlight.Found this:

author: Magicmushroom666
author_rank: Contributor
timestamp: November 21, 2013, 08:37:32 am
content: You can usually change LCDs from normal to inverse operation (such as here) by just rotating the front polariser by 90 Degrees I think, Have done this in the past before with a standard car stereo LCD.

author: Balaur
author_rank: Unknown
timestamp: November 21, 2013, 09:00:11 am
content: Quote from: Magicmushroom666 on November 21, 2013, 08:37:32 amOr just reverse the polariser foil (turn it on the other side)

author: Wytnucls
author_rank: Super Contributor
timestamp: November 21, 2013, 09:01:00 am
content: Thanks, I think you're right. Not sure how it works yet, but I found this wikipedia picture:So there shouldn't be any power hit.The LCD screen is transflective, meaning that during daytime, ambient light is reflected back and at night, it is LED illuminated through a red filter.

author: Wytnucls
author_rank: Super Contributor
timestamp: November 21, 2013, 11:08:04 am
content: Well, it has, but the backlight is energy hungry, so can't be left on all the time, hence the button press. Some generator powered by wrist movement might work one day.

author: dannyf
author_rank: Super Contributor
timestamp: November 21, 2013, 12:04:34 pm
content: QuotePositive lcd + red filters / background.
OMRON 1.5kW Variable Frequency Drive - Page 1
Forum section: electronics / projects

author: tom66
author_rank: Super Contributor
timestamp: July 04, 2012, 09:56:13 pm
content: This was in the WEEE bin at workStuff ends up in there for one of two reasons;- it's faulty- it's not needed any moreSo, I need to find out which. I have NO idea on how to wire this thing up. I have only a single phase washing machine motor, and I suspect this is a three phase U/V/W drive.I would love to make this into an AC power supply for testing small things in isolation. However, if I am not wrong, it has no isolation between input and output? If so, that makes it less useful, I already have a variac. Still, I am not complaining. It was free.

author: Unknown
author_rank: Unknown
timestamp: July 05, 2012, 12:57:24 am
content: http://www.google.com.au/search?q=3g3xv%2Buser+manual&ie=utf-8&oe=utf-8&aq=t&rls=org.mozilla:en-GB:officialHard isn't it?

author: SeanB
author_rank: Super Contributor
timestamp: July 05, 2012, 05:17:02 am
content: No isolation between input and output, and they complain if there is not a motor load only. great to power a drill press though, variable speed, reversing and infinitely variable gearbox inside. I am looking for a small one to do this to my drill press, will just buy a new motor when I find one, not going to rewind a small motor from split capacitor to 3 phase.

author: T4P
author_rank: Super Contributor
timestamp: July 05, 2012, 05:28:51 am
content: Most motors are 3 phase anyway, they are just split capacitor to curve the lagging phase by about 90 degrees out of phase7hen it comes to variable speed ones they are definitely PSC motorsbut the common ones will be Split-phase*Sent from my laptop with HD 5430 using RockMelt

author: tom66
author_rank: Super Contributor
timestamp: July 05, 2012, 05:33:34 am
content: Quote from: Uncle Vernon on July 05, 2012, 12:57:24 amExcuse me if I don't want to kill myself doing something I've never done before.

author: mAJORD
author_rank: Contributor
timestamp: July 05, 2012, 05:37:56 am
content: seanBif you live in aus, omron have ssingle phase vfd on special from $140 for 4Kw to $195 for 1.5kwSent from my GT-I9100 using Tapatalk 2

author: amyk
author_rank: Super Contributor
timestamp: July 05, 2012, 07:08:55 am
content: The mention of "washing machine motor" and the model of the VFD reminded me of this:https://www.youtube.com/watch?v=J2guzKTBFdg#t=4m57s

author: T4P
author_rank: Super Contributor
timestamp: July 05, 2012, 12:05:44 pm
content: Quote from: amyk on July 05, 2012, 07:08:55 amAH YES!

author: tom66
author_rank: Super Contributor
timestamp: July 06, 2012, 07:05:20 pm
content: Well, it's on ebay if anyone's interested. I'd love to make use of it, but it looks like it won't do what I want.http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&item=130726167201
Omron switch alternative  - Page 1
Forum section: electronics / projects

author: ANTALIFE
author_rank: Frequent Contributor
timestamp: March 23, 2021, 10:40:56 am
content: Hey AllI am looking to get some "miniature" snap action switches for a hobby project, and was wondering if anyone knew of alternatives to the following Omron switches:D2JWseries, 12.7x5.3x9.4mm bodyD2FDseries, 12.8x7.7x6mm bodyD2Fseries, 12.8x6x5.8mm bodyD2MQseries, 8.2x6.5x2.7mm bodyD3Cseries, 8x6x4.2mm bodyNo need to give a full PN, just a manufacturer name is enough

author: cheater
author_rank: Regular Contributor
timestamp: March 23, 2021, 04:06:33 pm
content: Try looking at Kailh. They have very tiny switches in their Ali store.

author: wizard69
author_rank: Super Contributor
timestamp: March 23, 2021, 05:26:22 pm
content: There are so many options here that I'm not sure where to start. Microswitch (Honeywell) comes to mind first. Cherry, Alco, C&K, Banner, Altech and E-Switch are just a start when it comes to these types of switches. I wouldn't be surprised to find 50 different manufactures if you looked hard enough.Your best bet is to go to your favorite online vendor and search for snap action switches or sometimes limit switches. These types of switches are so wide spread in industrial applications that some of the local electrical distributors to electricians will have some on the shelf.Quote from: ANTALIFE on March 23, 2021, 10:40:56 am

author: wraper
author_rank: Unknown
timestamp: March 23, 2021, 05:31:49 pm
content: LCSC sells cheap alternatives which cost 10 times less. They are mostly ok. I suggest Yuandi.
Omron Sysmac C200H PLC installed in 1987, RAM memory, Still functions - Page 1
Forum section: electronics / projects

author: bluetrepidation
author_rank: Newbie
timestamp: December 31, 2016, 11:05:43 pm
content: Hello members,I just made a quick video. I removed this and though it was great that the program was stored in RAM and the backup battery is original. Does the test of time prove that this is a good product? Any ides on some fun things to do with this? Tear down?Video Link:https://youtu.be/YLthxyyW9ToThanks,A.J.

author: jeroen79
author_rank: Frequent Contributor
timestamp: January 03, 2017, 03:40:44 pm
content: Quote from: bluetrepidation on December 31, 2016, 11:05:43 pmA teardown would be interesting.Maybe reprogram it? Is there a 'hello world' for PLCs?
<expired> - Page 1
Forum section: electronics / projects

author: karpouzi9
author_rank: Contributor
timestamp: March 27, 2023, 07:01:56 am
content: <expired>

author: Aiy
author_rank: Regular Contributor
timestamp: March 28, 2023, 06:48:02 pm
content: Hi there,Interesting. If I understand you correctly you want to do something similar to this:https://numato.com/kb/usb-3-0-a-cost-effective-high-bandwidth-solution-for-fpga-host-interface/They combine the USB3.0 FTDI FT601 for high bandwidth, with a USB2.0 FT2232H for FPGA JTAG in a sidechannel scheme.Best regards

author: SiliconWizard
author_rank: Super Contributor
timestamp: March 28, 2023, 07:22:36 pm
content: I wouldn't expect this to work with most USB hosts. I haven't checked in the USB 3 standard to confirm, I suspect it would not be supported at least as standard, but something to check.From an OS POV, I don't think you could have one USB port acting as several USB ports (so here a USB 3 port acting both as a USB 3 SS/SS+ and USB HS/FS/LS on the D+/D- pair.)I'm not aware of this port sharing capability at least, it would somehow imply that each USB 3 port would have its own mini-hub, if you see what I mean.Also, I think a host with an USB 3 port will first try to enumerate the device on the D+/D- pair before switching to the other pairs for SS/SS+? So if two different devices are actually connected to these pairs, that would wreak havoc on the enumeration process completely.So don't have a definitive answer, but I wouldn't expect this to be possible. Curious to see if it's actually doable though.

author: SiliconWizard
author_rank: Super Contributor
timestamp: March 29, 2023, 04:23:01 am
content: Quote from: karpouzi9 on March 29, 2023, 03:35:39 amYep I get that and it could be interesting, so keep up posted. I guess this would be for adding a USB 2 peripheral that is completely unrelated to your USB 3 connection? Like a third-party device?Otherwise you can of course always create acomposite USB devicethat will show up as several devices on the same port.

author: tszaboo
author_rank: Super Contributor
timestamp: March 29, 2023, 08:42:30 am
content: Quote from: SiliconWizard on March 28, 2023, 07:22:36 pmI think in the so-called 'alternate mode' the USB 2.0 signals can be used separately from the 3.0 signals.And all this needs to be negotiated through those CC and SBU pins, not the 2.0 sinal pins, before entering this mode. At least that's how I understand it. The actual implementation, I have no idea. I expect headache, where you need to make .ini files and driver signatures before getting your PC to actually work with it.
On board IC exposure and use - Page 1
Forum section: electronics / projects

author: ChrisGreece52
author_rank: Frequent Contributor
timestamp: January 30, 2015, 11:24:46 am
content: Hello i recently got a blown cheap multimeter from a friend and i was harvesting smd components of of it.Then i got an idea to expose the IC (which is under the black blob thing) and cut a hole on the circuit board to use it as a keychain piece.But i have a few concerns ...What item should i use for scraping the blob and will the pcb hold onto the keychain or it will break?I have scratched some of the blob off with scissors but this is very inaccurate...So im open for advice thank you .

author: ChrisGreece52
author_rank: Frequent Contributor
timestamp: January 30, 2015, 11:44:06 am
content: Here are some pictures from the board

author: helius
author_rank: Super Contributor
timestamp: January 30, 2015, 02:56:50 pm
content: the black blob is epoxy. it's not easy to remove without powerful chemicals, although if you heat it long and hot enough with a hot air gun it will become frangible.there are reports that dichloromethane and methyl-ethyl ketone can soften epoxy blobs. the problem is, how will they react with the epoxy of the PCB? they are available at hardware stores, but you still should always treat chemicals with caution and respect.

author: senso
author_rank: Frequent Contributor
timestamp: January 30, 2015, 09:12:52 pm
content: A hot air gun makes that crumble in a couple minutes at most, no need to use crazy chemicals.

author: ChrisGreece52
author_rank: Frequent Contributor
timestamp: January 31, 2015, 11:47:58 pm
content: Thanks about the suggestions ... i have not a hot air gun available but i did a pretty good job scratching the epoxy with scissors ... i was not easy but i finally got the chip exposed when i get home ill try using the hot air gun to see if ill be able to expose the wires too thank you
On building an AM radio - Page 1
Forum section: electronics / projects

author: technix
author_rank: Super Contributor
timestamp: October 13, 2016, 03:03:29 pm
content: I found some remnants of my old solder-free DIY AM radio kit - the inductor with its magnetics and the tuning capacitor. I wonder if I can still make an AM radio out of it.The plan was to use an op amp with enough gain-bandwidth product to amplify the tuned AM signal directly, demodulate it using 1N5711 Schottky diode and an RC filter, and use another op amp (preferrably the second gate in the same dual op amp chip) to amplify the audio signal, and push a pair of push-pull transistor into a small speaker.Does this make sense? Can I use some jellybean op amp like NE5532 for direct RF amplification at about 1MHz? If jellybean op amps may not work, can I use something like a biased unbuffered CMOS inverter like 74LVC1G04?

author: wine+dine
author_rank: Contributor
timestamp: October 13, 2016, 03:34:47 pm
content: Depending on what you want to do, one or two transistors might do. Opamps are overkill.Just google images for "simple transistor am receiver" which will get you lots of schematic ideas.A regenerative circuit will give RF amplification and demodulation with one transistor or FET (or vacuum tube as it once was). You could add an LM386 for more audio power.

author: jh15
author_rank: Frequent Contributor
timestamp: October 13, 2016, 03:44:25 pm
content: Wonder what stations you will receive. Over here, FCC has been considering AM station power increases to get over the fog of in-home devices.I used to just run a longwire antenna to a tree when I was around 9. Coil, germanium diode, Black plastic high impedance headphones.Now, I'd probably just connect it to outside when no lightning storms around.

author: technix
author_rank: Super Contributor
timestamp: October 13, 2016, 04:00:20 pm
content: Quote from: jh15 on October 13, 2016, 03:44:25 pmI live a few miles away from one of the city's major radio towers that broadcasts all stations available in the city (on top of the Radio Building itself.) From the balcony of my apartment I even have clear lines of sight to both major radio towers - Radio Building and Oriental Pearl Tower - in my city (the line of sight to Radio Building is only slightly obstructed from the window in my lab.) And both radio towers in the city broadcast at very high power that can cover over 150km even on FM band.