hybridfree/eevblog-posts huggingface dataset:
New to FPC Connectors - Page 1
Forum section: electronics / beginners

author: ssashton
author_rank: Frequent Contributor
timestamp: June 03, 2023, 02:33:11 pm
content: Hi!I'd like to use FPC connectors and cable between two boards I'm designing but I have never used them before.Are all 0.5mm pitch FPC connectors inter-compatible? Do they take the same cables?I'm using JLC so looking at their parts and don't want to pick something I'll have trouble finding a cable for. Currently keen on this one, but I'll probably want one vertical and one horizontal plug -https://www.lcsc.com/product-detail/FFC-FPC-Connectors_JUSHUO-AFC07-S20FCC-00_C11055.htmlThanks!

author: tooki
author_rank: Super Contributor
timestamp: June 03, 2023, 02:40:45 pm
content: The only real “gotcha” I’m aware of is which side of the flat flex the contacts are on: they can be on either side. Depending on how your device comes together (and how the flat flex is folded or curled to match) one or another configuration (contacts on the same side on both ends, or on opposite sides) may make more sense.Note that connectors sometimes come in versions for both orientations. The one you linked, for example, says “bottom contacts”.
New to impedance matching | 868MHz | Ceramic Chip Antenna - Page 1
Forum section: electronics / beginners

author: mrburnzie
author_rank: Regular Contributor
timestamp: October 19, 2019, 06:44:09 pm
content: Hi!I'm new to building RF stuff and I need a bit of help for matching the 50rule.I have chosen the CMWX1ZZABZ-091 module that will run LoRa at 868MHz.For the antenna I have chosen this one:http://www.farnell.com/datasheets/2280483.pdfI have copied the antenna footprint with all the dimensions required.1. In the datasheet it says that it is highly recommended to add a pi-network, which I have added. Do I have to use the values that are given in the datasheet? (by have to use I mean do I have to solder them)2. I want to a use a FR4, 2 layer board, made by aisler.net. I have calculated the trace width and clearance via kicads calculator:. I'm not sure if I did it right, can I get confirmation on it?3. The calculator says that I need a 1.05mm width trace, but for the module used (CMWX) I can't directly connect the 1.05mm trace to the pin, because the pins width is 0.7mm... what should I do?4. Should I use it without the bottom ground plane? The calculator (if I use it right, not sure) gives me this:5. I don't have the right instruments at hand to properly match the impedance. What is the best recommendation for newbies to match the impedance?Cheers!

author: mayor
author_rank: Regular Contributor
timestamp: October 23, 2019, 10:30:25 am
content: Hi,1. Pi Network: you can't just use values from the datasheet. Your match will be influenced by a number of things like ground plane size, layout, enclosure, etc. The best way to do this is to use a VNA (there are cheap ones which might do the trick). I've used the xaVNA, happy with it.For impedance matching of the trace from source to antenna, you can get away without matching it at all if it is short enough (say less than 1/10 wavelength). Can't speak to the tool you're using or your board, but in all cases, it was easier for me to use CPWG than without ground.As far as going to a smaller pin, I don't think that's an issue. Get as close to the device as you can, then match em up. If TI does it in their reference designs, that's good enough for me! They do it for a good number of antennas here:http://www.ti.com/lit/an/swra351a/swra351a.pdf
new to logic analysers - Page 1
Forum section: electronics / beginners

author: Norton
author_rank: Newbie
timestamp: August 29, 2020, 05:07:55 pm
content: I have posted this in beginners because after a quick perusal of the the other forums, it is fairly evident that I am not as clever as I thought was.I am playing with my first logic analyser (hantek 5022 (garbage)) in an attempt capture the data transimitted between a machine and a receipt printer (SII dpu-20) over a parallel port, with the intention logging the data as text.Using the pinouts for a similar printer (I can't find a data sheet on the original), I have worked out the data pins, which are self-evident once seen on the screen. The rest of what is happening is a mystery to me though.Based on what I have learned about how parallel communications work, I would expect for find a strobe signal for each change of state on the data lines, followed by a BUSY and/or ACK, but I am reading several bits between strobes.My best guess as to what is happening is that I am reading electrical noise from the DC motor running the printer as bits. No amount of screwing around with grounds has changed the nature of the signal.. The laptop, analyser, device, printer, and power supply are all connected to the same outlet, and I have even run jumpers between all of the ground points on all the devices attached without change. The printer is printing everything it should be with the analyser attached. In the sample provided, the printer is receiving the text "POWER UP", or "DATE:01:01:16".in the attached screenshot, I have highlighted a gap between strobes to show the timing. What made me suspect noise was that when I set the analyser to scan at 4Mhz, the strobe pulses register at 250 nanoseconds (or less), which I believe is a bit fast for such an old protocol.Can anyone shed some light on what I am looking at here?

author: Doctorandus_P
author_rank: Super Contributor
timestamp: August 30, 2020, 12:46:45 am
content: The most common cause is to set the sample rate too low.A decent minimum is to capture data at such a rate that you have at least 4 samples of each signal state before a bit flips.Other common problems are:* Logic levels that are different between the LA and DUT.* Bad probing, long GND wires etc.Also, in your next screenshot, please make it smaller. 1000 * 800 pixels is suficient for such screenshots, and allows web browsers to display them completely without scaling (which makes text very small).
New to me Leader 8101 oscilloscope. I need some help. - Page 1
Forum section: electronics / beginners

author: DC Jack
author_rank: Contributor
timestamp: September 19, 2025, 10:01:46 pm
content: I just picked up a Ledger 8101 oscilloscope for 50$ Canadian pesos to upgrade my cheap LCD scope. I wanted to be able to to see the RF eye pattern in a CD player to properly adjust the laser.This is my first time using a scope with knobs and switches, and I like it. I have one problem though. I don't know what the other options on the time scale knob mean and I can't find a user manual. I'm hoping someone can shed some light on it?

author: Zenith
author_rank: Frequent Contributor
timestamp: September 19, 2025, 10:22:25 pm
content: The big outer part of the knob (A) is the main timebase. The middle part (B) is a second timebase and the small inner part is to make the main timebase variable, which is sometimes useful. They usually have a clickable CAL (calibrated) position. The second timebase is usually set to a higher speed than the main timebase and is used to expand a part of a waveform you are interested in. The second timebase may have its own trigger and possibly a delay, so you can easily home in on a part of the waveform you are interested in.If you are totally new to analogue scopes, there are a few Youtube videos you may find useful, such as

author: DC Jack
author_rank: Contributor
timestamp: September 19, 2025, 11:02:29 pm
content: Oh Damn, I think I get it!I thought the TIME/DIV was part of the picture showing the B knob in the middle. Silly me. I just played around with it and is look like I can split the screen of the scope horizontally and "zoom" in on a section of the input while keeping the original input still in view.This is so COOL!
New-to-me power connector - Page 1
Forum section: electronics / beginners

author: elroy
author_rank: Regular Contributor
timestamp: July 12, 2019, 12:50:03 am
content: I just bought a small RF preamp from an online seller in China. The RF in and out are via standard SMA ports.For the +12vdc and ground, a connector is provided that consists of a hexagonal nut, a protruding pin ~5mm long that I assume is for the ~12vdc, and a side lug with a solder hole which must be for ground.Now, I could just solder appropriate-gauge wires to the pin and the lug and call it a day. But is there any smarter way to attach to a connector like this?

author: Brumby
author_rank: Unknown
timestamp: July 12, 2019, 01:18:41 am
content: It's not really a connector, as such, but it is being used in that role. It's an RF "feed through" which is simply a coaxial conductor running through an insulating material inside a metal body.It is not uncommon to see feed-throughs used in RF equipment as it allows a controlled entry/exit of connections through a shielded enclosure. Dave has done at least one teardown of an oscilloscope which show this.While I'm not an RF guy, I can see they offer some useful advantages:* Hermetic seal. No issues with moisture ingress or humidity changes* Fixed capacitance, which can help in circuit designYes, the simplest method of connection is soldering. My first thought would be to use a coaxial style cable between this preamp and your power supply - but maybe an RF person could offer a more informed suggestion and whether a connector option is available.

author: ArthurDent
author_rank: Super Contributor
timestamp: July 12, 2019, 01:19:32 am
content: The power is soldered to a feedthru capacitor. Here is a similar one. Some are straight pins, some are like mine.

author: David Hess
author_rank: Super Contributor
timestamp: July 12, 2019, 03:10:16 am
content: They make big machined collet socket pins which can fit on a lead like that but usually a wire connection is just soldered to it.

author: edpalmer42
author_rank: Super Contributor
timestamp: July 12, 2019, 03:25:46 am
content: Quote from: ArthurDent on July 12, 2019, 01:19:32 amI've seen both 'feedthru capacitors' and just 'feedthru' versions. Often, a feedthru capacitor will have a value printed or stamped on it.Ed
New to Metrology - Page 1
Forum section: electronics / beginners

author: Qyrone
author_rank: Newbie
timestamp: May 18, 2014, 09:57:10 pm
content: Hi guys,I understand this is possibly a silly thing to be asking as i've read a lot of the other posts.. Yet, I do need your advice.I'm starting a new career as a Metrologist (in training) and I'd like to know how I can get a better understanding of everything that has to do with calibraions. What do you guys suggest I start reading-up on to learn quicker?Thanks in advanced for your time.

author: gdewitte
author_rank: Unknown
timestamp: May 19, 2014, 01:21:55 am
content: Check out Fluke's app. notes on calibration:http://us.flukecal.com/category/literature-type/articles-and-education/electrical-calibration/application-notes?geoip=1

author: robrenz
author_rank: Super Contributor
timestamp: May 19, 2014, 01:28:04 am
content: I assume you are talking electronic metrology.Fluke's "Calibration Philosophy in practice" Second edition

author: retrolefty
author_rank: Super Contributor
timestamp: May 19, 2014, 01:54:27 am
content: Golden rule: Measurement changes behavior.

author: KSP
author_rank: Regular Contributor
timestamp: May 19, 2014, 11:44:32 am
content: I have been in calibration for about 5 years now, and I must agree that Fluke's notes are probably the best. I also fond that calibrating old HP/Agilent kit is pretty good for training because the service manuals are all on their website and most of them have a step-by-step calibration and performance test section. You will blindly follow it word-for-word at first, but gradually you will start to understand why tests are taken, why certain protocols are followed, etc.Agilent also have some training notes available as well. Back To Basics, Measurement Fundamentals, etc. etc.worth a look
new to soldering - Page 1
Forum section: electronics / beginners

author: scope
author_rank: Newbie
timestamp: August 05, 2014, 05:52:40 pm
content: I have just watched your video on drag soldering with a well-based tip. See:https://www.youtube.com/watch?v=b9FC9fAlfQE.Go to 18.21 to a well-based tips clean up a short. I need to solder pin headers onto arduino uno shields and such. See:https://learn.adafruit.com/system/assets/assets/000/010/738/medium640/adafruit_products_2013_09_02_IMG_2133-1024.jpg?1378136827MY question is: If I use a well-based tip for soldering on headers? I suppose I need to apply the solder individually to each pin.Thanks, Steve

author: jancumps
author_rank: Unknown
timestamp: August 05, 2014, 06:28:31 pm
content: Yes, one by one. Well and Drag soldering is for smd packages
New tutorial video: Basics of PLLs - Page 1
Forum section: electronics / beginners

author: w2aew
author_rank: Super Contributor
timestamp: September 01, 2012, 01:01:08 am
content: For those that are interested, here's a video that describes the basics of phase locked loop circuits and the fundamentals of frequency synthesis with a PLL.

author: IanB
author_rank: Super Contributor
timestamp: September 01, 2012, 03:41:16 am
content: That was a good tutorial. I often wondered how PLLs worked, and now I see. Thanks!

author: robrenz
author_rank: Super Contributor
timestamp: September 01, 2012, 04:05:05 am
content: +2

author: BravoV
author_rank: Super Contributor
timestamp: September 01, 2012, 06:30:24 am
content: Thanks a lot, an excellent video !

author: DarkPrince
author_rank: Regular Contributor
timestamp: September 01, 2012, 04:10:36 pm
content: Thanks for the video. Was fun to watch. Smoothed some of the rough edges I had with PLLs... and now I am tempted to play with them.

author: BravoV
author_rank: Super Contributor
timestamp: September 01, 2012, 05:09:12 pm
content: Noob question, with this PLL chip 4046, is there any example circuit to make an "adjustable" frequency multiplier or divider ?I googled around, can't find any.

author: BravoV
author_rank: Super Contributor
timestamp: September 01, 2012, 05:16:32 pm
content: Just remembered when I saw those vulnerable hooks you got there, just a suggestion, get a hot glue gun to make them like this :The picture is from the thread I posted while ago here ->https://www.eevblog.com/forum/projects-designs-and-technical-stuff/(tips)-strengthen-the-diyself-made-hook-probe's-join-using-hot-glue-gun/.

author: Thor-Arne
author_rank: Unknown
timestamp: September 01, 2012, 06:33:19 pm
content: Quote from: BravoV on September 01, 2012, 05:09:12 pmTake a look at this:http://www.qsl.net/yo5ofh/projects/cmos%20rf%20synthesizer/cmos%20rf%20synthesizer.htm

author: flano
author_rank: Contributor
timestamp: September 01, 2012, 10:57:02 pm
content: Excellent video. Thanks.

author: djsb
author_rank: Super Contributor
timestamp: September 02, 2012, 09:29:58 am
content: Very good video. Just need to find a video tutorial on PLL loop filter design. The maths in the application notes can be a bit off putting.

author: kg4arn
author_rank: Unknown
timestamp: September 02, 2012, 12:10:47 pm
content: Excellent video! You really distill the topic to its essentials.

author: MikeK
author_rank: Super Contributor
timestamp: September 02, 2012, 03:14:04 pm
content: Very nice! Thanks, Alan.

author: w2aew
author_rank: Super Contributor
timestamp: September 20, 2012, 02:06:30 am
content: Quote from: jim_griff on September 20, 2012, 01:51:55 amThe TI part you bought should work in substantially in the same fashion as the old Motorola MC14046 part I used. The TI part is a newer, improved part. It is basically pin compatible. It has a third variation of the Phase Detector, in addition to the two I described in the video. So, go ahead and play with this part, it'll be fine!

author: Mechatrommer
author_rank: Super Contributor
timestamp: September 20, 2012, 05:37:51 pm
content: thanks! deserve like button.
new two this stuff - Page 1
Forum section: electronics / beginners

author: Aestor
author_rank: Newbie
timestamp: July 05, 2013, 07:54:36 pm
content: HIi'm new two this stuff and don't know where i can buy the tools and supply's i tryed local shops but no luck they only sell cheap soldering irons that just plug in . I just wanted to know if anyone knows where i can buy all the gear and have a trust worthy supply of parts . love eevblog site just what i was looking for to start soldering repairs . i have no experiences in soldering but really want to learn .thank you guys so much

author: croberts
author_rank: Regular Contributor
timestamp: July 05, 2013, 08:11:37 pm
content: I recently bought a HAKKO FX-888D soldering station and have been very happy with it.

author: wbeaty
author_rank: Contributor
timestamp: July 05, 2013, 08:12:49 pm
content: Cheap soldering irons are fine when just starting out. Not so good for surface mount chips though. Me, I built an entire motherboard with a 300-watt soldering gun. (That was long ago, with big DIP components with large spacing.)What's your location? Some places have little-known hobbyist outlets.For example, here in Seattle there's Vetco:http://www.vetco.net/And besides Radio Shack (or Tandy,) do you have a Fry's Electronics nearby?Other than that, it's mail order.

author: croberts
author_rank: Regular Contributor
timestamp: July 05, 2013, 08:24:05 pm
content: Can you place online orders from your location? I ordered my HAKKO soldering station from amazon.com but you can find a lot of good suppliers by just doing a Google search for what your interested in. Unless you live in or near a large city it can be hard to find a place to buy electronic equipment and supplies off the shelf.

author: Aestor
author_rank: Newbie
timestamp: July 05, 2013, 09:55:54 pm
content: I live in Canada, Nova Scotia . you guys know of any online sites you use and trust that i can get supply's from because all i got is the source and they are bad for parts . i tryed to do a search but just don't trust them

author: madshaman
author_rank: Frequent Contributor
timestamp: July 05, 2013, 10:02:44 pm
content: For Canada:http://www.digikey.cahttp://www.mouser.comhttp://www.newark.comAll very reliable and fast shipping.Another is:http://www.arrow.comThe last supplier seems very motivated to steal customers from the first three.

author: nanofrog
author_rank: Super Contributor
timestamp: July 05, 2013, 11:11:02 pm
content: +1 on the Hakko FX-888D (excellent value for money IMHO)Here's an eBay seller that will ship to Canada (used a Halifax zip to get an idea of shipping). Bit more expensive than the US once you include the shipping & import fees, but not horrible IMHO.http://www.ebay.com/itm/Hakko-FX888-23BY-FX888-Soldering-Station-Replaces-936-12-Solder-Station-/170990362664?pt=LH_DefaultDomain_0&hash=item27cfd1e028
New ultrasonic cleaner trips GFCI - Page 1
Forum section: electronics / beginners

author: windsmurf
author_rank: Frequent Contributor
timestamp: April 13, 2019, 11:46:08 am
content: So I just got an X-Tronic ultrasonic cleaner on EBay, and I'm not sure if it has an issue or not.I wanted to use it by the bathroom sink, but when I do, it trips the GFCI whenever the Ultrasonic inducer starts up.Powering the unit on works fine, and heater works fine. Its only when I start the ultrasonic degas or sweep or standard, it trips GFCI.If I plug it into another outlet without GFCI, it works fine.So I used my UT210E to measure current on the white, black, and green wires. White and black both measure properly the amps being used by the heater and inducer. The ground wire does show some current but its 1 milliamp when I turn on the cleaner, and up to 3 milliamps when I turn on the inducer. 0 when the unit is off. I don't know how accurate the UT210E is at such low current...Is this "normal"? Should I return the cleaner, or perhaps get it replaced with the same model/different unit? Or should I just use an outlet outside the bathroom and get a GFCI extention cord to attach it perhaps? I wonder if that will trip as well or if the bathroom GFCI is just very sensitive...Appreciate any comments or suggestions!
new UT202A+ clamp meter - incorrect readings ?! - Page 1
Forum section: electronics / beginners

author: mike_mike
author_rank: Super Contributor
timestamp: November 19, 2021, 04:47:56 am
content: Hello! I have a new Unit UT202A+ clampmeter. I tested it and I found that the clamp does not work OK, because when I placed the masured wire right in the center of the clamp, then it reads, for example, 6A ac. But when I move the wire to the one of the extremities of the clamp then it shows me a difference of about 0.5-0.6A ac.I found on various forums, than some of people said that this is normal and some people that this is not normal.Please tell me what you think about this situation ?

author: mike_mike
author_rank: Super Contributor
timestamp: November 19, 2021, 05:16:38 pm
content: I made a few more tests and I found that:If I measure the current through the wire while powering a 220V AC/1000W heater which also has a fan:1. With the wire on the upper side of the clamp I=4.710A2. With the wire on the center side of the clamp I=4.660A3. With the wire on the lower part of the clamp (the most close to the meters body) I=4.419AIf I just close the clamp to the wire, while powering the same load as above:1. With the upper side of the clamp I read I=0.022A2. With the center side of the clamp I read I=0.099A3. With the center side of the clamp I read I=0.134APlease have a look and tell me what you think ?

author: Manul
author_rank: Super Contributor
timestamp: November 19, 2021, 09:38:45 pm
content: The wire must be passing through the inside of a closed clamp, like a rope through a ring. Some small errors are expected, clamp meter is not a precision instrument.

author: Benta
author_rank: Super Contributor
timestamp: November 19, 2021, 09:43:31 pm
content: You do realise, that only ONE wire must go through the clamp, right? You need to split the power cable to do the measurement.

author: mike_mike
author_rank: Super Contributor
timestamp: November 20, 2021, 09:04:55 pm
content: Yes, I measured the current by splitting the cable.I am still a little bit confused, and I don't know why it shows different readings if I move the wire inside the clamp ?

author: BeBuLamar
author_rank: Super Contributor
timestamp: November 20, 2021, 11:53:53 pm
content: The manual did say that you should have the wire at the center of the clamp. If you don't you get another 1% of inaccuracy although your readings show more than 1%.
New video: Basics of Ferrite Beads in Filter Applications - Page 1
Forum section: electronics / beginners

author: w2aew
author_rank: Super Contributor
timestamp: March 22, 2013, 01:20:36 am
content: Introduction to the characteristics of ferrite beads and their application in filter applications such as EMI/RFI Suppression, parasitic oscillation control, supply filtering, etc. as usual, a mix of discussion and demonstration.

author: BravoV
author_rank: Super Contributor
timestamp: March 22, 2013, 01:42:51 am
content: Another great video, thanks !

author: FenderBender
author_rank: Super Contributor
timestamp: March 22, 2013, 02:51:45 am
content: You keep cranking these out! My hat off to you. Great stuff.

author: AlfBaz
author_rank: Super Contributor
timestamp: March 22, 2013, 03:16:49 am
content: This is very serendipitous, I was just on the cusp of starting a thread asking what ferrite beads did, a reference design I have has one in series with a BAT54 schottky feeding the mcu's analog supply.Thank you very much!!

author: w2aew
author_rank: Super Contributor
timestamp: March 22, 2013, 12:50:12 pm
content: Quote from: FenderBender on March 22, 2013, 02:51:45 amThanks! I try to find time to do about one per week, although it doesn't always work out that way.

author: firewalker
author_rank: Super Contributor
timestamp: March 22, 2013, 08:50:23 pm
content: Great videos!Alexander.

author: dentaku
author_rank: Frequent Contributor
timestamp: March 23, 2013, 12:36:29 am
content: Great stuff. I just added your Youtube channel to my Favorites.

author: IvoS
author_rank: Frequent Contributor
timestamp: March 23, 2013, 01:04:41 am
content: I recently purchased a book "The Art of Electronics" to learn some more electronic stuff. I am often tired or lazy to learn from the book, don't ask me why....fatigue. Your videos are much better source of information for me since you keep it clear, factual and concise, plus I can see the behavior on the scope.

author: madshaman
author_rank: Frequent Contributor
timestamp: March 23, 2013, 01:09:23 am
content: +1 to your videos are awesome, perfect style and presentation.
New video: Basics of Phase Dots on Transformer Windings... - Page 1
Forum section: electronics / beginners

author: w2aew
author_rank: Super Contributor
timestamp: August 12, 2015, 03:03:43 am
content: ...what they are, why they matter (sometimes), and how to keep track of them when winding your own transformers. The signal phases with respect to the phasing dots is demonstrated on the oscilloscope.

author: vindoline
author_rank: Unknown
timestamp: August 12, 2015, 03:57:14 am
content: Anther great video. Thanks Alan! Can you explain when it is appropriate to twist the wires together before winding the transformer and when you should not? That's always confused me.

author: Melt-O-Tronic
author_rank: Frequent Contributor
timestamp: August 12, 2015, 05:48:06 am
content: I've wondered that too. For twisted filaments, what effect does the continuously varying distance from each wire to the core have on electromagnetic coupling or perhaps capacitance? It seems to me that when they're twisted, that effect would be fairly uniform and probably self-cancelling if it exists at all.Similarly, When winding common mode chokes with stiff wire, I've often wondered if having the odd air gap here & there between a wire and the core (or between individual conductors in a pair) has any discernible effect.I imagine at HF frequencies none of the above is likely to be of concern, but perhaps at very high frequencies?

author: T3sl4co1l
author_rank: Super Contributor
timestamp: August 12, 2015, 05:59:52 am
content: Core has nothing to do with it -- proximity to the other wires in the winding(s) are what matters.Tim

author: w2aew
author_rank: Super Contributor
timestamp: August 12, 2015, 01:11:18 pm
content: Quote from: vindoline on August 12, 2015, 03:57:14 amIt is commonly done in RF circuits to maintain a consistent coupling between the two wires, much like a twisted-pair transmission line.

author: vindoline
author_rank: Unknown
timestamp: August 12, 2015, 06:56:05 pm
content: Quote from: w2aew on August 12, 2015, 01:11:18 pmThanks. What is the best method if one or more of the coils have a different number of turns?

author: w2aew
author_rank: Super Contributor
timestamp: August 12, 2015, 07:29:46 pm
content: Quote from: vindoline on August 12, 2015, 06:56:05 pmI'll usually wind each one separately, starting with the one with the most turns, and then work my way down. If the application uses two turns connected in series, then I'll often wind as a single winding, with a tap at the appropriate number of turns.
New Video: Basics of PIN diodes - Page 1
Forum section: electronics / beginners

author: w2aew
author_rank: Super Contributor
timestamp: November 09, 2013, 02:59:23 am
content: My latest video is a tutorial on the basics of PIN diodes, and their use in RF switching applications. Enjoy!

author: Vgkid
author_rank: Super Contributor
timestamp: November 09, 2013, 05:58:25 am
content: Thanks for the video, I was always wondering hown in diodes were used for attenuators. What would you reccomond as far as further reading on the topic?

author: KJDS
author_rank: Super Contributor
timestamp: November 09, 2013, 09:34:34 am
content: Here's one of several Macom app notes on PIN diodes.https://www.macomtech.com/Application%20Notes/pdf/AG312.pdf

author: rastro
author_rank: Frequent Contributor
timestamp: November 09, 2013, 03:00:19 pm
content: Excellent video - thanks

author: codeboy2k
author_rank: Super Contributor
timestamp: November 10, 2013, 02:26:33 am
content: excellent video, thanks.. Always well presented..Series-Shunt Single-Pole, Single-Throw... say that over and over again while tapping your head and rubbing your belly

author: Vgkid
author_rank: Super Contributor
timestamp: November 10, 2013, 06:26:12 am
content: Thanks for the link KJDS.
New video: Basics of RF mixers in radio receiver applications - Page 1
Forum section: electronics / beginners

author: w2aew
author_rank: Super Contributor
timestamp: March 09, 2013, 04:01:12 pm
content: I put this video together to discuss the basics of RF mixers, and the role they play in a super-heterodyne receiver.

author: gxti
author_rank: Frequent Contributor
timestamp: March 09, 2013, 10:09:28 pm
content: Cool! I think I had the basics down, but watching peaks wiggle around on a spectrum analyzer really makes it clear.

author: w2aew
author_rank: Super Contributor
timestamp: March 11, 2013, 12:27:48 am
content: Quote from: gxti on March 09, 2013, 10:09:28 pmCool - I'm glad the visualization of the signals on the spectrum analyzer, and watching how they move as you tune, helped with your understanding.

author: robrenz
author_rank: Super Contributor
timestamp: March 11, 2013, 12:44:36 am
content: Great video, I thought I had no interest in radio related stuff but I find your presentations too interesting to ignore.

author: BravoV
author_rank: Super Contributor
timestamp: March 11, 2013, 12:47:49 am
content: Quote from: robrenz on March 11, 2013, 12:44:36 am+1

author: BartManInNZ
author_rank: Contributor
timestamp: March 11, 2013, 03:07:45 am
content: This is great stuff - a good refresher for an old hand who has been out of the loop for too long!
New video: Basics of the Gilbert Cell - multiplier/mixer/modulator - Page 1
Forum section: electronics / beginners

author: w2aew
author_rank: Super Contributor
timestamp: December 22, 2015, 01:19:18 am
content: My latest video, by multiple requests, is a basic overview of the operation of a Gilbert Cell four quadrant analog multiplier, mixer, balanced modulator, etc.

author: Unknown
author_rank: Unknown
timestamp: December 22, 2015, 03:34:38 am
content: Thanks for these videos, Alan - as always, a nice clear and concise explantion of the subject. I often find myself referring to them as a refresher or referring others to them to save them from my mangled explanationsOne thing that's never been particularly intuitive to me is the common use of the NE602 & friends as an RF->IF mixer, particularly when used as a switching downconverter/mixer (e.g. as typical in 10.7MHz/455kHz IF -> 12kHz soundcard SDR adaptors). There's something there that just doesn't stick with me, and I'm not quite sure what - maybe how it manages to convert without destroying the amplitude/phase information carried in the RF/IF signal (particularly when the LO is a square wave)? Regardless, every time I need to understand/explain it I have to go either go back & watch your balanced mixer videos, or just grab a NE602 & prove it to myself, before sitting and thinking hard about it...Maybe a subject for a future video?

author: w2aew
author_rank: Super Contributor
timestamp: December 22, 2015, 02:23:28 pm
content: Quote from: Tac Eht Xilef on December 22, 2015, 03:34:38 amOn thing that might help clear this up for you - remember that a square wave is nothing more than a sine wave plus its odd harmonics (properly scaled and phased of course). Using a square wave as the LO is often done to keep the switching elements out of their linear region (or to traverse the linear region quickly). Depending on the mixer structure, this helps improve LO and RF rejection. The higher order harmonics create additional mixing products, each of which preserves the amplitude/phase modulation of the RF signal. It is up to the filter after the mixer to select which mixing component you want to use.

author: krivx
author_rank: Frequent Contributor
timestamp: December 22, 2015, 04:08:34 pm
content: Really enjoyed this video, thanks. I've never touched multipliers before but I think I'll have a play around.
New video: basics of the VBE Multiplier circuit - Page 1
Forum section: electronics / beginners

author: w2aew
author_rank: Super Contributor
timestamp: March 20, 2015, 10:30:07 pm
content: The video briefly describes what it is, and demonstrates how it works, and shows a typical application or two, including using it to adjust the bias point of a push-pull output stage.

author: IanB
author_rank: Super Contributor
timestamp: March 20, 2015, 10:34:07 pm
content: Another very nice video!

author: TerminalJack505
author_rank: Super Contributor
timestamp: March 21, 2015, 02:37:11 am
content: I always learn something new from your videos, Alan! I've never seen this particular circuit before.Keep up the good work.I would love to see you make a video on op amp compensation.

author: juani_c
author_rank: Contributor
timestamp: March 21, 2015, 04:19:54 am
content: Awesome video! I read about the Vbe multiplier in an article about the 7805 (http://www.righto.com/2014/09/reverse-engineering-counterfeit-7805.html) but I didn't understand it much back then...It was related to the bandgap reference, do you think you can make a video about that?thanks!

author: David_AVD
author_rank: Super Contributor
timestamp: March 21, 2015, 05:39:35 am
content: What an excellent video - very clearly explained.

author: joejoe317
author_rank: Contributor
timestamp: March 21, 2015, 08:59:41 am
content: Wish I saw this when I had to make my audio amplifier for school!

author: robrenz
author_rank: Super Contributor
timestamp: March 21, 2015, 02:38:48 pm
content: Excellent job Alan, keep them coming.

author: photon
author_rank: Frequent Contributor
timestamp: March 22, 2015, 07:52:34 am
content: I subscribed.

author: kizzap
author_rank: Unknown
timestamp: March 22, 2015, 11:57:10 am
content: Great video Alan.Somehow I had developed that circuit/copied from schematics online in designing a push/pull amplifier front end for a function generator. Your video filled in the blanks to my understanding of the circuit very well, and that is greatly appreciated.Keep it up!-kizzap
New Video: Circuit Analysis - Page 1
Forum section: electronics / beginners

author: TimNJ
author_rank: Super Contributor
timestamp: March 22, 2015, 08:07:08 pm
content: Hi everyone,Today's my last day of spring break and I finished recording this video just in time. This video is an introductory circuit analysis video that starts from Ohm's Law and ends with superposition. It basically covers all of the relevant topics you might learn in the first half of a second year circuit analysis class. I'm planning a second video that will cover capacitors, inductors, AC, and op-amps. But that probably won't be out for a while. It's pretty long at about an hour and a half, but there is a lot of information and I work through examples for each method. So if you watch it, hope you enjoy it!Thanks!
New video: Common Emitter Amplifier design tips & shortcuts - Page 1
Forum section: electronics / beginners

author: w2aew
author_rank: Super Contributor
timestamp: November 30, 2017, 03:49:10 pm
content: This has been a long requested topic on my channel.

author: rstofer
author_rank: Super Contributor
timestamp: November 30, 2017, 05:17:53 pm
content: Outstanding!

author: nugglix
author_rank: Regular Contributor
timestamp: December 01, 2017, 09:35:20 am
content: Quote from: rstofer on November 30, 2017, 05:17:53 pmIndeed!Ishouldhave done the accounting for the last month...

author: tpowell1830
author_rank: Frequent Contributor
timestamp: December 01, 2017, 12:18:45 pm
content: Nice job, as always, W2AEW, I always learn something new every time I watch one of your tutorials.BTW: You sound great on the o'scope ads as well, congrats! I think that is part of why I like your vids, your smooth, very clear, enunciated voice. Not to mention (well the main reason) your content is always spot on.
New Video: Essential & Practical Circuit Analysis Part 2: Op-Amps - Page 1
Forum section: electronics / beginners

author: TimNJ
author_rank: Super Contributor
timestamp: July 29, 2016, 10:58:03 pm
content: Hi everyone,I've been meaning to put out the second part of my circuit analysis series for a long time (more than a year). And I finally got around to recording it recently.This video takes you from the basics, all the way through the typical building block circuits, and applications.Enjoy!Tim

author: rstofer
author_rank: Super Contributor
timestamp: July 30, 2016, 12:48:35 am
content: That's a great video! Thanks.I seem to have had a little trouble when it came to analog computers. Somehow the video plays longer than the time shown when it first starts but quits right after the diagram of the suspension system.It turns out that my only interest in op amps IS analog computing. It's kind of fun modeling equations I had a heck of a time solving in college.

author: TimNJ
author_rank: Super Contributor
timestamp: July 30, 2016, 04:34:56 am
content: Thanks! The video seems to work fine for me. I'll see if anyone else says they have problems.Analog computing really interests me too. Even bought a few books from the 50s and 60s. But unfortunately, I havent had much time to work on any hardware. GK has done some amazing things though.Glad you liked the video. Thanks.

author: rstofer
author_rank: Super Contributor
timestamp: August 01, 2016, 01:16:26 am
content: Quote from: TimNJ on July 30, 2016, 04:34:56 amIt played fine this time.I have been thinking about buying an arbitrary waveform generator for the specific purpose of providing x(t). A more cost effective scheme might use a DAC on an Arduino...This is the analog computer I built and it works very well. It has just enough integrators (2) to do the equations of motion. It has sin(t) and a multiplier plus 2 summing amplifiers and an inverter. All it does is make me want a larger analog computer!http://www.analogmuseum.org/english/homebrew/vogel/
New Video: Oscilloscope probe ground lead length's affect on signal integrity - Page 1
Forum section: electronics / beginners

author: w2aew
author_rank: Super Contributor
timestamp: December 07, 2012, 03:45:15 am
content: I posted another video in the "scope basics" series tonight - this one talks about oscilloscope probe ground lead length, and it's affect on measured signal integrity.

author: Shuggsy
author_rank: Regular Contributor
timestamp: December 07, 2012, 06:24:13 am
content: Love your videos. Some remind me of Jim Williams' app notes... particularly with the full copper-clad PCB this time!

author: w2aew
author_rank: Super Contributor
timestamp: December 07, 2012, 02:52:12 pm
content: Quote from: Shuggsy on December 07, 2012, 06:24:13 amOOOH - that's aHUGEcompliment!!! Thank you! Jim Williams was a true wizard! I was lucky to meet him a few times and exchange stories...

author: saturation
author_rank: Super Contributor
timestamp: December 08, 2012, 12:12:48 am
content: Great video. You showed everything step by step, or rather inch by inch of lead, and how it matters.

author: SeanB
author_rank: Super Contributor
timestamp: December 08, 2012, 05:15:47 am
content: There was a query on the blog related to this yesterday, referred them to this video.........
New Video Teaching Series  - Page 1
Forum section: electronics / beginners

author: TheOCDengineer
author_rank: Contributor
timestamp: July 13, 2017, 03:36:40 am
content: Hi Everyone, I created a intro into circuits teaching video on my youtube channel. I was wondering if you you guys could check it out and give me some feedback on the video. I am trying to figure out if it is worth it to make a full series as it takes a quite a bit of work to make these videos.Thanks

author: RoGeorge
author_rank: Super Contributor
timestamp: July 13, 2017, 07:35:40 am
content: Very nice intention, much appreciated!Now, brace for impact: In 7 minutes from atoms and electrons, to two glasses of water, to solar cells with car batteries and energy conservation, to conductors and semiconductors, to ideal voltage and current sources, to Ohm and Kirchhoff, to superposition and solving simple electric circuits, all backed up by calculus formulae about electricity. Just stating laws and facts, and give some numeric examples. No explanations, and no demonstrations. It looks more like a first page of a cheat sheet from the first year of EE. Nobody can follow all those topics in the video unless the topics are already well known. If the topic are already known, then why watching the video?1. Who's your intended audience?2. What prerequisite knowledge do you expect from your audience?3. Why would one want to watch your videos instead of competitor's videos?I know, these are harsh words for a first video, and I apologize. No harm intended.I wish you all the best for your new channel!Constructive advice:- Don't jump all over the place. Take one subject only and explain it. Don't just throw a formulae.- Always assume your audience have no idea what you are talking about.Always keep your camera on a tripod, or at least a monopod.Nice editing and montage, good sound, nice and fluent narrating.

author: TheOCDengineer
author_rank: Contributor
timestamp: July 14, 2017, 02:47:25 pm
content: Thanks For the reply, I could have the video 1 hour long but from my experience with long teaching videos the average watch time is very low. For my KiCad video which is over an hour long most people only watch 4 minutes of it. So I wanted to see how much I could fit in a 7 minute video, maybe it is best for it to be an overview video to get people started but I am not sure.

author: jiro
author_rank: Contributor
timestamp: July 14, 2017, 06:34:22 pm
content: Quote from: TheOCDengineer on July 14, 2017, 02:47:25 pmI think it is not a bout the video time , I'm guessing you asume that the intended audience have more knolwdge do understand and follow the video easily, if that's not the case perhaps you should take more time in every topic.If you intended audience is new people in electronics I'd suggest to keep the 7 - 10 minutes format, but take more time to explain the topics with more details so it is easier to follow when you get into more advanced topics
New video: Visualizing RF Standing Waves on mis-terminated transmission lines - Page 1
Forum section: electronics / beginners

author: w2aew
author_rank: Super Contributor
timestamp: August 04, 2015, 12:22:43 am
content: This video shows how standing waves are created on transmission lines from the addition of the forward (transmitted) wave and the reflected wave resulting from unmatched termination impedance.

author: KD0CAC John
author_rank: Frequent Contributor
timestamp: August 04, 2015, 03:08:32 am
content: Another good video , thanks again .I wandered a while back that if measuring directly on feedline , that I should measure in multiple places , not just one spot .

author: w2aew
author_rank: Super Contributor
timestamp: August 05, 2015, 01:04:08 pm
content: Quote from: KD0CAC John on August 04, 2015, 03:08:32 amIt all depends on the length of the line with respect to the wavelength of the signal being transmitted.This also explains why - if you're having trouble adjusting your transmatch/tuner on a given band, that it can often help to add/remove some line between the tuner and antenna - because the impedance looking into a mismatched line will vary with line length (at a given operating frequency). Adding or removing a bit of line can move the impedance off of a difficult-to-tune impedance extreme (node or anti-node).

author: ElectroIrradiator
author_rank: Frequent Contributor
timestamp: August 05, 2015, 01:47:37 pm
content: That little experiment brings back memories.Long time ago I literally measured the wavelength of an abused 2K25 X-band klystron by noting the distance between troughs in the standing wave reflected from a flat metallic surface, sitting perpendicular to the incident radiation. The metallic surface was a piece of polished PCB, and the slide it was riding on incorporated a micrometer. This was done because the 2K25 normally won't tune up into the 10GHz amateur band, but ... with a bit of help from a persuasion device...
New videos: RF circuits through block diagrams - Page 1
Forum section: electronics / beginners

author: vk3yedotcom
author_rank: Frequent Contributor
timestamp: March 29, 2013, 05:36:19 am
content: Something for those here wanting some stuff on basic RF.In these videos I take a 'building blocks' approach to understanding basic circuitry for RF.Part 1. The four important RF families: Oscillators, amplifiers, mixers and filtersPart 2. Putting stages to work: receivers, transmitters and transceivers
New w2aew - Why are my oscilloscope voltage readings wrong? Top 5 reasons.. - Page 1
Forum section: electronics / beginners

author: Cliff Matthews
author_rank: Unknown
timestamp: May 20, 2020, 11:36:02 am
content: New W2AEW #311 videodescribes the top 5 reasons that you might think your oscilloscope voltage readings are wrong.PDF Notes:https://www.qsl.net/w2aew/youtube/WhyScopeReadingWrong.pdfThese are the most common mistakes made by new users and professionals alike. They are:1) Voltages are off by a factor of 10- usually due to not accounting for 10x probe attenuation.See this video about 1x/10x probes:2) Voltages off by a factor of 2- usually due to using a signal generator that is expecting a 50 ohm load.See this video for more details:3) All voltage readings lower than they should be- usually caused by not putting the volts/div vernier into the Calibrated position.See this video on one reason that this control exists:4) High frequency voltage readings low- could be several reasons, but most often due to signal frequencies being too close to the scope/probe rated bandwidth.See these videos on scope bandwidth considerations:5) Probed voltage amplitudes are not right- most often caused by improper 10x probe compensation.See this video on the importance of probe compensation:
newb AC circuit question - Page 1
Forum section: electronics / beginners

author: Nokia3310
author_rank: Contributor
timestamp: November 11, 2022, 04:04:18 pm
content: Say you have a circuit consisting of a diode and a resistor. You plug the circuit into a household AC socket and look at the waveform across the resistor. I think I'm right in saying you would see half the AC cycle because the diode blocks the other half?Say you keep everything the same, but now you probe across the live and neutral pins of the plug. Would you still see half the cycle or would you see the full cycle? I'm not going to do it I was just wondering.If you see half cycle is the diode blocking current just as far as the socket because the other sockets in the circuit are joined in parallel directly at the back of the socket you're plugging into? Or is the diode blocking current all the way back to the source?

author: Manul
author_rank: Super Contributor
timestamp: November 11, 2022, 04:44:41 pm
content: On the resistor side: voltage is half cycle, current is half cycle. On the socket side: voltage is full cycle, but current is half cycle. Does that make sense and help?So yes, to answer directly, you will have full cycle (sine) voltage on the socket side.

author: Nokia3310
author_rank: Contributor
timestamp: November 11, 2022, 06:25:13 pm
content: Quote from: Manul on November 11, 2022, 04:44:41 pmThat's what I wanted to know and it makes sense. Thank you

author: james_s
author_rank: Super Contributor
timestamp: November 11, 2022, 06:50:52 pm
content: Why don't you try it in a simulator and find out?This is a very simple circuit simulator that works surprisingly well.https://www.falstad.com/circuit/

author: Nokia3310
author_rank: Contributor
timestamp: November 11, 2022, 08:40:09 pm
content: Quote from: james_s on November 11, 2022, 06:50:52 pmThat's a great site. Very helpful for visualising what is happening. Thanks for posting it. I made the circuit and it shows what Manul said. The voltage is full cycle before the diode which is what I wasn't sure about