hybridfree/eevblog-posts huggingface dataset:
gain/phase error from not having reflection/transmission kit  - Page 1
Forum section: electronics / testgear

author: CopperCone
author_rank: Super Contributor
timestamp: July 24, 2018, 07:30:08 pm
content: Thought this might be a better forum since its pretty specific to test equipment:So I have a VNA that has the capability to measure reflection/transmission but it does not have a build in directional coupler or whatever the 87512A is. The manual says to simply use a power splitter. I tracked down that there is a option to use a 87512A with it.I guess taking reflection measurements only using a power splitter to supply the reference channel does not make sense... but how much error does the reflection cause for a typical gain/phase measurement? The VNA is a E5100A and it goes to 300MHz.I mean the reflection goes into the reference port through the external power splitter. It seems really bootleg. the 87512A has 40dB directivity. How can it make any meaningful measurements if it gets that reflection?Is there something I am missing in my understanding of how this works? Are reflections just really small typically? I don't really know what % of the signal power is lost in a reflection.

author: bson
author_rank: Unknown
timestamp: July 26, 2018, 07:17:11 am
content: The error should be entirely dependent on the short cal accuracy. For an accurate reflection measurement you also need an accurate open cal.

author: CopperCone
author_rank: Super Contributor
timestamp: July 26, 2018, 07:27:45 pm
content: You mean the error with the power splitter?BTW I looked at other assemblies from HP/Agilent/Keysight that perform the same function as a reflection/transmission analyzer add-on and the circuit diagram looks like a power splitter that is connected to the R port through a black box (not sure if this is a resistor/attenuator or a isolator and then to a directional coupler.I think the directional coupler only isolates the coupled port (3), and between 1 and 2 you just have a attenuator (10dB in the case of the coupler), so you have a 6db loss on the power splitter, then a 10dB loss from the directional coupler (which is not directional in attenuation for a signal you pass)I thought it would be designed like a dual directional coupler.How come they go to use a directional coupler, resistive splitter and some kind of series thing (either resistor/attenuator or isolator, drawn as a black rectangle) rather then a dual directional coupler?Is it just because the thing goes down to low frequencies where you can't use a directional coupler to feed the R port? (the HP recommended part is DC to GHz).. I would assume a microwave VNA just uses a dual directional coupler rather then the weird hybrid of splitter and coupler?What are practical low frequency limits for a directional coupler? Do they have ones that use the stripline coupler and a transformer to handle wide bands?>
Rohde & Schwarz HMO 1202 battery pack? - Page 1
Forum section: electronics / testgear

author: hazzer
author_rank: Regular Contributor
timestamp: July 26, 2018, 05:21:13 pm
content: Has anyone added a battery pack or external DC jack to the HMO1202 series DSO?It was mentioned in one of the early videos as a possible mod - it looks like it all runs from a 12V internal PSU.Hazzer
DIFFERENCE  HP8595E and HP8563E  video monitor  - Page 1
Forum section: electronics / testgear

author: jean françois
author_rank: Contributor
timestamp: July 23, 2018, 12:53:30 pm
content: Hello everyone,On my HP8595E the video monitor output at the back of the camera is working properly on the video input of a TV pal secam.on my HP8563E it does not work (unfortunately the tube is very tired) ..In your opinion are the two video outputs of these devices should work or is the video output of the HP8563E is down?Can someone help me?thanks in advanceJean François

author: kirill_ka
author_rank: Frequent Contributor
timestamp: July 23, 2018, 08:10:16 pm
content: Quote from: jean françois on July 23, 2018, 12:53:30 pmThose video outputs are totally different things. Video output of HP856xE can't be connected to a monitor. It's proportional to vertical deflection of CRT beam.

author: jean françois
author_rank: Contributor
timestamp: July 26, 2018, 12:40:05 pm
content: Hello,Thank you for your response and thank you for raising the doubt.as I do not see very well on the device,I only have one solution, it is to adapt an LCD display like the onefromwww.simmconnlabs.com/thanks again for your informationJean François
HP 8562E power supply failure - Page 1
Forum section: electronics / testgear

author: Plocmstart
author_rank: Newbie
timestamp: July 25, 2018, 02:55:57 am
content: I'm working on a 8562E spectrum analyzer that was given to me awhile ago because it no longer powers on. I finally got around to looking at it and found that Q201 has completely blown away (photo attached). So far I've only found the service guide which has a block diagram of the supply, but no schematic or component list so I have no idea what Q201 should be replaced with. I'm also wondering what else could have been destroyed along with this part. The service manual does mention a step in debugging where this part might end up being shorted, but no mention of it blowing open!Anyone out there with experience with this supply that could provide some suggestions?Thanks in advance!

author: TiN
author_rank: Super Contributor
timestamp: July 25, 2018, 04:16:24 am
content: You can get CLIP with schematics for HPAK 8562E atArtek Manuals.Welcome to forum.

author: Plocmstart
author_rank: Newbie
timestamp: July 25, 2018, 04:28:45 am
content: Thanks! Just placed my order. Hope to breathe some life back into this thing soon.

author: kirill_ka
author_rank: Frequent Contributor
timestamp: July 25, 2018, 05:30:24 am
content: There is PSU schematic for HP8563A. It may be similar or the same as HP8562E.https://community.keysight.com/thread/5234Update:Found another one, this should be for E seriesCLIP PSU 08564-60008.pdfhttps://community.keysight.com/thread/18492

author: Plocmstart
author_rank: Newbie
timestamp: July 26, 2018, 04:44:13 am
content: Thanks for the help. I've found that it's a N-channel FET, and it's part of a kick-start circuit that's supposed to generate +14V. Looks like it's blown because something on the +14V rail is currently shorted. Time to start pulling parts and hope it's not the hard-to-find ones.There's also a beefy-looking PTC thermistor in the path (195Q80115) that's supposed to read 750ohm @ 25C, but it's currently reading ~960ohm so it's possibly damaged. I found a very old datasheet, but it doesn't list the current/power requirement. It has a "switch temperature" of 95C so I guess it was supposed to also act like a resetable fuse, but failed to do so at some point before the FET blew.
Iet prs200 programmable resistance substitute - Page 1
Forum section: electronics / testgear

author: phantom1
author_rank: Newbie
timestamp: July 23, 2018, 05:35:38 pm
content: Hello all and thanks for any input on thisThe issue I am having with the 'Iet prs200" is that is seems if I use any of my hand held multimeter's on it, a 1mega ohm or higher all is good as you can see picture show up fine but when I use a bench meter like my gw instek anything after a 1meg setting like say 2meg from the Iet, it shoots up to a 10meg reading on any of my bench meter's? it seems to cap out at 15meg with the iet set for 9meg and I checked with my hp 3478a as well and same thing happens. Not sure as to why this is happening, i was thinking a setting on the bench meters but can't seem to find anything to stop it from doing this. Though maybe has something to do with voltage or frequencies ? at a loss thanks again for any help would like a schematic or anything for this unit if anyone has it thanks I did find the user info pdf but it just has some specs more of a sales pdf .

author: phantom1
author_rank: Newbie
timestamp: July 24, 2018, 01:44:26 am
content: well I figured it out turns out for whatever reason not sure but I tried changing the polarity on the probe wires pos to neg and that did the trick.why... not sure but i guess because it is a powered unit that is the IET prs200. just guessing with I had some docs/schematics, not sure why it didn't effect the hand held multimeter's but i tried on a bm235 otc3990, deree 5000, and aneng an8008 all worked fine so for whatever reason both hp 3478a, and the gw instek gdm-8251a had to change polarity. if anyone has any ideas please let me know thanks or any schematics

author: Vgkid
author_rank: Super Contributor
timestamp: July 24, 2018, 05:12:10 am
content: Have you tried cleaning the terminals of your bench meters with Q-tips and IPA? That is my guess.Does everything work fine on the lower ranges?
Voltlog #173 - µAmp Current Source (Mentions  EEVblog current source) - Page 1
Forum section: electronics / testgear

author: johnlsenchak
author_rank: Frequent Contributor
timestamp: July 24, 2018, 03:19:43 pm
content: Voltlog #173 - µAmp Current SourceVoltLogPublished on Jul 24, 2018
Fluke 15b+ Multimeter for electronics - Page 1
Forum section: electronics / testgear

author: Hexenbyte
author_rank: Newbie
timestamp: July 23, 2018, 09:45:46 pm
content: Hi all, i am looking to buy a good multimeter to use for electronic repair and projects and was looking at the Fluke 15b+, is this a good one to get? thank you for the help in advance.

author: nanofrog
author_rank: Super Contributor
timestamp: July 23, 2018, 10:19:25 pm
content: It depends on what's important to you. Feature wise, it's decent (. But it's not necessarily the best value out there or even the safest.So what all are you looking to do with it?Will you need it to poke around mains as well as low voltage electronics?For example, it'd be safe enough to poke around mains, but if you're working with an AC signal that's not a true sine wave, you won't get an accurate value as it's not a True RMS meter.It's also 4000 counts. 6000 counts is usually all you'll need for most applications, and given the budget, that can be had in a safe meter for less money.For example, you might want to consider either the:Brymen BM235Brymen BM257SBoth are well built, safe for mains (meet their CAT ratings), 6000 counts, and True RMS. Just some differences in features you'd need to sort out if you need them or not.A lower cost alternative that's suitable for mains would be aUni-T UT139C. Also 6000 counts and True RMS. Not a Brymen, but certainly usable.If it's just for low voltage electronics, you could even opt for anAneng AN8008.As it's usually handy to have multiple meters for simultaneous measurements, any combination of these (or others would be in order). Just stabbing in the dark really without any specifics.Lots of info on these meters in the forum if you search, and would be well worth your time IMHO.

author: Fungus
author_rank: Super Contributor
timestamp: July 24, 2018, 10:00:54 am
content: Quote from: Hexenbyte on July 23, 2018, 09:45:46 pmYes.Only basic features but a good, safe, reliable meter.
Probe recommendations for young people - Page 1
Forum section: electronics / testgear

author: tim.savage
author_rank: Unknown
timestamp: July 23, 2018, 04:02:40 am
content: My daughter (4) is getting more interested in the various tools on my electronics workbench, in particular, she loves getting hold of my Multimeter and using the continuity function to find things that conduct. While I encourage her curiosity, I don't want that curiosity to extending to sticking the probes into a mains socket.Can anybody recommend probes (quality doesn't matter) that have particularly fat tips to prevent such an occurrence (I'm in Australia so this is for an AU/NZ standard socket)?

author: tautech
author_rank: Super Contributor
timestamp: July 23, 2018, 04:21:35 am
content: Quote from: tim.savage on July 23, 2018, 04:02:40 amWelcome to the forum.Some DMM probes do come with little rubber or nylon slip on sheaths so only the tip is exposed and you won't get them into our mains sockets. If you can't immediately find such probes you can build up the probe pin diameter just with layers of heat-shrink. The last layer should go up the handle a little to stop them from falling off. A tiny dab of rubber modeling glue could be added to be double sure.Just the very point exposed is a good idea for most users to help prevent accidental shorts against another component or the DUT chassis.Keep that kid safe !

author: Muttley Snickers
author_rank: Unknown
timestamp: July 23, 2018, 04:53:43 am
content: Another option would be to get a set of the Brymen silicone test leads which are the same ones supplied with both the EEVblog BM235 and 121GW meters, they come with 4mm banana screw on tips which if fitted cannot be inserted into a GPO, a valued member here Franky from 99centhobbies sells them.99centhobbieshttps://www.ebay.com/str/99centHobbies/

author: tim.savage
author_rank: Unknown
timestamp: July 23, 2018, 05:06:51 am
content: Thanks for the responses, I picked up some leads from Jaycar with covers, I'll use some heat shrink to fix them on that should do the trick.Good to know about the Brymen leads, I have one of the EEVBlog meters and the leads are much nicer than those that came with my other meters, might get some of those for myself!Cheers

author: pigrew
author_rank: Frequent Contributor
timestamp: July 23, 2018, 03:53:58 pm
content: I'd provide banana to banana or banana to mini-grabber cables, they are not sharp at all. Maybe fashion together something like a maglock to prevent strain on the DMM ports?

author: David Hess
author_rank: Super Contributor
timestamp: July 24, 2018, 02:11:28 am
content: Buy a set of test leads, cut the probes off, and replace them with alligator clips. I usually replace the negative probe with an alligator clip anyway.
plz delete - Page 1
Forum section: electronics / testgear

author: sourcecharge
author_rank: Regular Contributor
timestamp: July 24, 2018, 01:16:30 am
content: Moved:https://www.eevblog.com/forum/projects/using-a-batteryinverter-w-mod-sinewave-on-a-siglent-fg-and-3-output-ps-126452/
Is the Hp8658a IF compatable with the 8568b RF section? - Page 1
Forum section: electronics / testgear

author: Simon Spiers
author_rank: Regular Contributor
timestamp: August 03, 2018, 08:33:24 pm
content: I have the chance of buying the RF section (lower section of an HO 8568B that from my understanding is comparable with the earlier HP processor A model.Can anyone confirm this is correct?

author: cncjerry
author_rank: Unknown
timestamp: August 04, 2018, 03:35:21 am
content: Yes, they are. There wasn't much changed in the A vs B model.

author: Simon Spiers
author_rank: Regular Contributor
timestamp: August 04, 2018, 10:55:14 am
content: Thanks a lot.
GPSTM returning to factory default / temperature reports constant value - Page 1
Forum section: electronics / testgear

author: tkamiya
author_rank: Super Contributor
timestamp: July 21, 2018, 07:30:23 pm
content: I have two Nortel GPSTM, a close cousin of Thunderbird. Oddly enough, when connected to Lady Heather, they report differently.One has "temperature" constantly changing and the other one reports a fixed value. On the latter box, if I inject some cold air by using a can of air, it will move, but otherwise, it is not reacting to room temperature change. I'd like to start my trouble shooting with giving it a factory reset. I also looked for firmware update but I could not find any. Nortel is in bankruptcy protection, so there's no way to contact them.Does anyone have experience with this?

author: texaspyro
author_rank: Super Contributor
timestamp: July 22, 2018, 05:45:09 am
content: Under the Lady Heather "!" keyboard menu is a factory reset command...

author: tkamiya
author_rank: Super Contributor
timestamp: July 22, 2018, 03:10:52 pm
content: -! seem to have done something ONCE on one machine. Have no effects on 2nd time. It does nothing on the second machine. Weird!Seem to be, displaning is working though. I fed one output to 10 digit counter's timebase input, and the other to channel 1. Only last digit flickers +/-1 and it's pretty stable.

author: texaspyro
author_rank: Super Contributor
timestamp: July 23, 2018, 04:57:19 am
content: Early Thunderbolts has a temperature sensor that could be read to around 0.01C Later production changed to a sensor with around 0.1 degree res. Perhaps they did something similar with the GPSTM. A lot of GPS equipment with temp sensors have a resolution of only 0.5 to 1.0 C.

author: tkamiya
author_rank: Super Contributor
timestamp: July 23, 2018, 05:18:46 am
content: I take it, this is just for FYI kind of thing? Performance does not seem to be affected.I'm assuming this is a temperature inside the receiver cabinet, not that of the oven...

author: TheSteve
author_rank: Unknown
timestamp: July 23, 2018, 08:05:40 am
content: Do they both have the same firmware version and hardware internally? I've seen a few different revs.

author: tkamiya
author_rank: Super Contributor
timestamp: July 23, 2018, 04:26:56 pm
content: The hardware is identical; however, firmwares are not. I can't find anything for updating them to the latest.
Walked into the Rigol office, walked out with scope - Page 1
Forum section: electronics / testgear

author: SteveOregon
author_rank: Contributor
timestamp: July 22, 2018, 09:48:30 pm
content: An interesting co-inky-dink . . .1.5 miles to my north is the Tektronix corporate campus, and 3.5 miles to my south is the only North American Rigol office here in Beaverton OR.After pondering a new scope for several weeks, finally settled on the DS2102E. Rigol's office isn't a walk-in store per say, but if you call them to arrange it, you can pick up a scope right from their office/warehouse (saved me shipping). When you walk in their front door, there are only office cubicles, but someone will meet you if they know you're coming.The Rigol office is in a nondescript business park..And the new scope. The active screen is courtesy of Corel PaintShop Pro X9.

author: Mr. Scram
author_rank: Super Contributor
timestamp: July 22, 2018, 10:19:53 pm
content: I kind of like the rustic outdoor feel of the second picture.

author: David Hess
author_rank: Super Contributor
timestamp: July 23, 2018, 01:17:22 am
content: Quote from: Mr. Scram on July 22, 2018, 10:19:53 pmThat is pretty typical for light industrial zones in the US plus I assume it is western Oregon which is very green.

author: Mechatrommer
author_rank: Super Contributor
timestamp: July 23, 2018, 03:07:36 am
content: how much price? btw Corel PaintShop Pro X9 is not doing a very good job there...

author: SteveOregon
author_rank: Contributor
timestamp: July 23, 2018, 03:32:12 am
content: QuotePrice was what's on their website ($647), with the free option bundle promotion included. Shipping free via 2007 Honda CR-V.Quick & dirty with Paint Shop Pro and I got a D- is scope photography 101.

author: Mechatrommer
author_rank: Super Contributor
timestamp: July 23, 2018, 04:23:42 am
content: I'm not sure why you didnt get the newer 4ch ds1000z version instead? any specialty of ds2000e version that ds2000z doesnt?

author: SteveOregon
author_rank: Contributor
timestamp: July 23, 2018, 04:33:59 am
content: QuoteI would never need four channels - and at my age an extra inch on the display is a bonus.

author: pascal_sweden
author_rank: Super Contributor
timestamp: July 23, 2018, 09:40:22 am
content: Is the logo sticker really in blue now? So RIGOL has changed their logo from yellow to blue?

author: SteveOregon
author_rank: Contributor
timestamp: July 23, 2018, 02:19:57 pm
content: QuoteAt least for this model. Data sheet, showing the new blue logo:https://beyondmeasure.rigoltech.com/acton/attachment/1579/f-0790/1/-/-/-/-/DS2000E_DataSheet_EN.pdf
Test/review of Power supply frontend DPS5015 50V/15A - Page 1
Forum section: electronics / testgear

author: HKJ
author_rank: Super Contributor
timestamp: October 30, 2016, 01:16:55 pm
content: I have tested the DPS5015 at different voltage and current levels.It is a module that can be used after any fixed voltage power supply to convert it into a decent lab power supply.Review:http://lygte-info.dk/review/Power%20DPS5015%20UK.htmlMany more charts:http://lygte-info.dk/review/Power%20DPS5015%20charts%20UK.html

author: BravoV
author_rank: Super Contributor
timestamp: October 30, 2016, 01:21:30 pm
content: Thanks for sharing.As you have a scope, any chance for transient response tests ?

author: HKJ
author_rank: Super Contributor
timestamp: October 30, 2016, 01:25:42 pm
content: Quote from: BravoV on October 30, 2016, 01:21:30 pmI did test with (electronic) load on/off, but it is not really that fast transients.

author: BravoV
author_rank: Super Contributor
timestamp: October 30, 2016, 02:02:52 pm
content: Quote from: HKJ on October 30, 2016, 01:25:42 pmOk, recommend to build a dynamic electronic load designed and also already built by respected eevblog member here ->Dynamic Electronic Load Project, using common parts and components. Its even posted in Dangerous Prototypes blog.Again, just a suggestion, as you are one of my respected reviewer, especially for batteries and chargers.

author: HKJ
author_rank: Super Contributor
timestamp: October 30, 2016, 10:57:20 pm
content: I do have some dynamic load included:But as you can see my load is fairly slow at turning on.

author: Dielectric
author_rank: Regular Contributor
timestamp: October 31, 2016, 01:58:35 pm
content: That's awesome, thank for all of the work! I was eyeing those modules up, thinking about piecing together a new supply with this 48V supply I have laying around. Looks good enough for home work, right? Probably way better than this old tank of a supply I have that I'm 75% certain is just a heatsinked LM317 and a transformer in a big metal box. The variable supply has like no current capacity.

author: bianchifan
author_rank: Regular Contributor
timestamp: November 20, 2016, 11:33:37 am
content: THX!!I discovered those DP/DPS models early this year when searching on infos about CPS-3205 models.And I was wondering about missing any useful information. Nowhere..., though they were offered on Ali pretty cheap.Not to forget, Banggood too.Over the time I forgot them.Some interesting chinese site.. MyDigit.cnDPS5005 disassambledDPS.. Load Test

author: RD Tech
author_rank: Regular Contributor
timestamp: July 31, 2017, 07:28:14 am
content: we just make a video for DPS5015 ripple test , you can compare it with your result ..https://youtu.be/QbcLtOT1IAQ

author: rev0
author_rank: Contributor
timestamp: July 23, 2018, 05:45:01 pm
content: Sorry to bump an old thread, but does anyone here know if these can be modified with sense leads for compensating for voltage drop? I do see sense traces on the board, but wonder if bad things would happen if I cut those and put them on external sense wires going to the test clips.
BM235 multimeter spam reviews 2 1/2 stars - Page 1
Forum section: electronics / testgear

author: Pulpo
author_rank: Newbie
timestamp: July 22, 2018, 07:02:42 am
content: Yep Dave you must have pissed someone off again, i'm guessing.A whole lot of garbage customer reviews.I mentioned to someone to buy this muiltimeter and they mentioned its poor customer rating.CheersPulpo

author: Muttley Snickers
author_rank: Unknown
timestamp: July 22, 2018, 07:49:57 am
content: Quote from: Pulpo on July 22, 2018, 07:02:42 amFrom what source are these reviews ?, please provide a link or citation so that your statement may be verified. Amazon rates this meter at 4.7 with 55 reviews and Ebay rates it at 4.9 from 17 reviews so that's hardly a bad wrap, as an owner and somebody who has recommended this product to others I am interested to know.

author: Pulpo
author_rank: Newbie
timestamp: July 22, 2018, 11:21:29 am
content: https://www.eevblog.com/product/bm235-multimeter/#reviewsI agree its a good multimeter.Cheers

author: Muttley Snickers
author_rank: Unknown
timestamp: July 22, 2018, 11:47:25 am
content: Quote from: Pulpo on July 22, 2018, 11:21:29 amMany thanks, it looks like someone is spamming that review page with advertisements for viagra or something, I have notified moderators accordingly so hopefully Dave can address the issue.

author: Fungus
author_rank: Super Contributor
timestamp: July 22, 2018, 12:10:14 pm
content: Quote from: Muttley Snickers on July 22, 2018, 07:49:57 am"Rap", the word is "rap"(sorry, just my OCD)

author: Simon
author_rank: Unknown
timestamp: July 22, 2018, 01:12:21 pm
content: Yes it's spam not actual reviews, I think Dave needs to set that reviews can only be done by "verified owners" or some other sort of spam setting needs upping.

author: rsjsouza
author_rank: Super Contributor
timestamp: July 22, 2018, 01:39:46 pm
content: Even still, a user (lastwarrior) that seems quite displeased with its quality still gave 4 stars. Quite interesting.

author: EEVblog
author_rank: Unknown
timestamp: July 22, 2018, 02:45:48 pm
content: Thanks.I've had to disable reviews for now.The (only?) 1 star review on Amazon is from none other than our old banned and serial stalking forum friend MojoChan!

author: EEVblog
author_rank: Unknown
timestamp: July 22, 2018, 02:46:53 pm
content: Quote from: Simon on July 22, 2018, 01:12:21 pmThe problem is I don't get people to create website account when buying something, they are all anonymous, as AFAIK, it's not easy to implement a legit review system in that case.

author: Simon
author_rank: Unknown
timestamp: July 22, 2018, 06:25:17 pm
content: Quote from: EEVblog on July 22, 2018, 02:46:53 pmYea, same with my shop, most check out as guests. I think you can force people to create accounts.
Hand made Agilent 33220A external timebase board (option 001) - Page 1
Forum section: electronics / testgear

author: gamalot
author_rank: Super Contributor
timestamp: October 19, 2016, 04:31:22 pm
content: It took me two nights to make this board, all schematics can be found in the service manual.

author: TheSteve
author_rank: Unknown
timestamp: October 19, 2016, 04:50:45 pm
content: Nicely done! I love "mods" like this.

author: JohnPi
author_rank: Regular Contributor
timestamp: July 21, 2018, 10:18:07 pm
content: Anyone know of a low cost source for these ? or a clone ?

author: bitseeker
author_rank: Super Contributor
timestamp: July 22, 2018, 05:36:19 am
content: Very cool, gamalot. Nicely done!
Can I get my MSOX to also transmit SPI or I2C? - Page 1
Forum section: electronics / testgear

author: king.oslo
author_rank: Frequent Contributor
timestamp: July 21, 2018, 06:30:07 pm
content: Hello there,I have a Keysight MSOX3035T fully loaded. I can use the protocol analyser to decode some of the common buses. But now I'd be interested in generating SPI or I2C on the fly with the scope. Can I do that somehow?Thanks.

author: pigrew
author_rank: Frequent Contributor
timestamp: July 21, 2018, 06:44:51 pm
content: No (at least as far as I know).It has a "demo" mode where it uses the probe compensation outputs to transmit patterns, and there are some example SPI-like signals (but with only two outputs). Theoretically, the signal generator could be a third output, but it isn't programmed to output SPI like that. In addition, you don't have any control it the demo signals....
Flann Microwave (FMI) motorised rotary attenuator - Page 1
Forum section: electronics / testgear

author: Astrodev
author_rank: Regular Contributor
timestamp: July 21, 2018, 01:27:55 pm
content: I know it is a long shot but does anybody have any information on the Flann rotary attenuators or their controllers. I have done searches on the web but have not found anything helpful.What I am looking for is the information on the pinouts of the connectors on the attenuator and the controller so I can make up some cables to connect them up.It would also be useful to find specs on the different models of attenuator in order to have a better idea of the frequency ranges of the different attenuator heads.Any info would be appreciated.
DIY Vector Network Analyser (mini circuits) - Page 1
Forum section: electronics / testgear

author: jpb
author_rank: Super Contributor
timestamp: July 21, 2018, 11:04:33 am
content: Having bought a few bits and pieces from mini circuits, I get their news e-mails and occasionally actually read them.The most recent one had a thing on a DIY vector network analyser kit which looked quite fun (aimed at students) though a bit pricey, of course, at $2.5k.It does go to 6GHz and I guess would have the advantage of being user repairable (just replace the duff component) in a way that more serious kit isn't.Here's a link to the pdf:https://ww2.minicircuits.com/pdfs/UVNA-63.pdf

author: nowlan
author_rank: Frequent Contributor
timestamp: July 21, 2018, 12:05:11 pm
content: Existing thread here.https://www.eevblog.com/forum/rf-microwave/how-to-build-a-do-it-yourself-vector-network-analyzer-thats-actually-useful/?topicseen

author: jpb
author_rank: Super Contributor
timestamp: July 21, 2018, 12:11:42 pm
content: Sorry, didn't spot that.I'm not sure I can delete this thread - if I delete my post it will probably just leave the thread hanging.
EEVBlog 121GW Multimeter unboxing /Kaizer Power Electronics - Page 1
Forum section: electronics / testgear

author: johnlsenchak
author_rank: Frequent Contributor
timestamp: July 20, 2018, 08:05:26 pm
content: EEVBlog 121GW Multimeter unboxingKaizer Power ElectronicsPublished on Jul 20, 2018

author: ggchab
author_rank: Frequent Contributor
timestamp: July 20, 2018, 08:55:31 pm
content: I received exactly the same box today (Belgium). Very happy
Rigol MSO1104: Hide Channel When Using Math? - Page 1
Forum section: electronics / testgear

author: eev_carl
author_rank: Regular Contributor
timestamp: July 25, 2018, 02:46:04 pm
content: Hi,I found an EEVBlog post that says you can't hide a channel, say CH1, that's involved in a MATH operation. It was from 2015 and I was wondering if this may have been added since.Thanks,Carl

author: hexreader
author_rank: Frequent Contributor
timestamp: July 25, 2018, 03:00:17 pm
content: As far as I can tell, there is no "hide" option for Channel display, only an "off" option, which kills the signal completely, making math with the channel meaningless.Moving the signal to top or bottom of screen reduces the display to a single line, which seems to be closest I can get to hiding the signal.My scope was bought December 2016, but I do not think there has been any update since.

author: Fungus
author_rank: Super Contributor
timestamp: July 25, 2018, 04:15:00 pm
content: Quote from: hexreader on July 25, 2018, 03:00:17 pmI think math works with the 'on-screen' data so that isn't really an option.

author: hexreader
author_rank: Frequent Contributor
timestamp: July 25, 2018, 05:02:45 pm
content: If you push the signals just a "little" way off screen, the math function seems to work, but push "too far" and the math display becomes inaccurate.Trouble is - how would anyone know they have gone "too far" when the signal is not visible?Sensibly, I guess it is best to keep all signals fully visible in order to have confidence that the processing will be done correctly.I think this principle applies to the other measurement functions too. If it is not visible, don't count on the scope giving a correct result.
Tektronix TDS2002 Unlock - Page 1
Forum section: electronics / testgear

author: TestSubject
author_rank: Newbie
timestamp: June 07, 2014, 03:09:01 am
content: I picked a Tektronix TDS2002 and was wondering if any firmware unlock was possible?

author: TestSubject
author_rank: Newbie
timestamp: June 11, 2014, 08:13:43 pm
content: Anyone? Maybe online resources I can refer to?

author: oaba
author_rank: Contributor
timestamp: July 19, 2018, 09:20:48 pm
content: Did you find any solution yet?I have saved the firmware from the flash memory. I would need some dump to compare.

author: tautech
author_rank: Super Contributor
timestamp: July 19, 2018, 09:47:46 pm
content: See here:https://www.eevblog.com/forum/testgear/tds-1000-2000-3000-bw-hack/
My Fluke 289 finally whups my Brymen 867s......at last! - Page 1
Forum section: electronics / testgear

author: Terry01
author_rank: Frequent Contributor
timestamp: July 18, 2018, 10:37:53 pm
content: I've been trying to justify the extra £££'s the 289 commands over the 867s and to be honest apart from the obvious 289 logging and couple other things the 867s doesn't have so can't compete I've been struggling.Tonight I found something!The 289 measures the capacitance between the rows of my breadboard quite well where the 867s won't at all!Well worth the extra couple hundred ££'s right??

author: joeqsmith
author_rank: Super Contributor
timestamp: July 18, 2018, 10:59:48 pm
content: I can believe that, except I would think to measure that high speed breadboard, you really need a VNA. It certainly justifies it.
Repair Fluke 8800A Or not - Page 1
Forum section: electronics / testgear

author: superstock
author_rank: Newbie
timestamp: July 19, 2018, 01:53:20 pm
content: My Fluke 8800A doesn't return to zero DCV after measurement ranges 20V and under unless the probes are shorted together (floating). Everything else seems to work fine.Is this a fault or were meters like this, I seem to recall my apprentice days shorting probes before measurements.I have placed a 40M resistor across the terminals which sorts it out but should I need to do this.Does anyone know if it's a fault or do they do this?On the schematic the DC buffer circuitry all seems common so am I chasing a red herring?Thanks peeps.

author: macboy
author_rank: Super Contributor
timestamp: July 19, 2018, 01:59:49 pm
content: This must be one of the most frequently asked questions on this forum. It is normal and is not a malfunction.The reason for this symptom is that the meter has an extremely high impedance input for those lower voltage ranges. This has the benefit of much less loading of sensitive circuits to give a more accurate reading. The disadvantage is that stray electric fields can cause the reading to jump all over if nothing is connected. Even waving your hand near the input will likely cause a noticeable change.

author: Fungus
author_rank: Super Contributor
timestamp: July 19, 2018, 04:08:33 pm
content: Quote from: superstock on July 19, 2018, 01:53:20 pmThat's a GOOD thing.What it means is the the impedance of the meter is so high that the electrons in the probe wires have nowhere to go after you disconnect them from the voltage.ie. the meter is measuring (and displaying) the difference between the number of electrons in each probe wire. When you short the wires they can equalize and it will go back to zero.
Siglent SDS1202X-E print date/time - Page 1
Forum section: electronics / testgear

author: wolferl1210
author_rank: Contributor
timestamp: July 28, 2018, 09:00:06 am
content: Hi all,All my .png screen shots generated on the USB stick with the 'Print' button having the date of 31.12.1979 23:00Is there a way to change this. Could not find a setting with the 'Utility' button on the scope, nor was there somethingmentioned in the manual.rgds

author: tautech
author_rank: Super Contributor
timestamp: July 28, 2018, 09:03:03 am
content: There's no way to change this in any X-E DSO's as they don't have a real time clock.

author: tv84
author_rank: Super Contributor
timestamp: July 28, 2018, 09:43:24 am
content: And manually?They seem to have SCPI commands::SYSTem:TIME and :SYSTem:DATE

author: BillB
author_rank: Unknown
timestamp: July 28, 2018, 12:42:32 pm
content: >>>:SYSTem:DATE 20180728>>>:SYSTem:DATE?20180728>>>:SYSTem:Time 083800>>>:SYSTem:Time?083801or, you can log into the console and use the Linux command:date -s 0728180841I think the programming manual for the SDS's are outdated. The manual for the SSA's seems more up-to-date. Of course, many of those commands don't apply to the scope.
Velleman WFS210 Android app apk - Page 1
Forum section: electronics / testgear

author: rogerjames99
author_rank: Newbie
timestamp: July 06, 2018, 10:15:38 am
content: Hi,Is there anyone who can provide me with a binary build/apk of @Avacee's modded version of the Android app for this unit? I only have Linux IDEs here. So it would be difficult to set up a Xamarin environment.Thanks,Roger

author: rogerjames99
author_rank: Newbie
timestamp: July 17, 2018, 11:38:23 am
content: I have now managed to build apks for @Avacee's C# version and for the the original Velleman Java based app. The xamarin build environment on Linux for C# is complex and not very usable. Velleman's aWFS210 github repo contains a java based Android implementation that has not been touched for four years. The aWFS210 subdirectory of the main Velleman WFS210-App github repo is a port of the original java app to C#. This subdirectory is used to provide the Android APK.My current idea is to backport the C# changes to the original java app. This gives me a much simpler Android Studio Java build process and removes the xamarind dependencies. I will create a new repo under rogerjames99 that will contain a standard Android Studio build environment.As a wild speculation, I wonder if I could get a quote from Velleman to buy up their old stock which they seem to be dumping and then crowdfund a project to raise the cash.Roger
Molecular Clock - 231.060983 GHz reference oscillators almost atomic grade - Page 1
Forum section: electronics / testgear

author: RoGeorge
author_rank: Super Contributor
timestamp: July 17, 2018, 01:30:02 pm
content: If these will be put in mobile phones, we all will soon have almost atomic grade reference oscillators with a cost in the range of single digit mW and $.https://techxplore.com/news/2018-07-molecular-clock-greatly-smartphone.htmlCheng Wang et al. DOI: 10.1038/s41928-018-0102-4

author: mmagin
author_rank: Frequent Contributor
timestamp: July 17, 2018, 09:53:51 pm
content: Maybe. If they can make it cheap and tiny and low power and reliable.200+ GHz semiconductors aren't cheap today. And this isn't especially better stability than good OCXOs -- it's better than anything else low power that you can fit in your phone, I suppose.To be fair though, it's a neat paper.
HP 400 series analog AC voltmeters - Page 1
Forum section: electronics / testgear

author: 001
author_rank: Super Contributor
timestamp: July 17, 2018, 02:22:34 pm
content: Anybody know, what model is best for hum measurments?What about latest versions? Did You knew IC-based variants?

author: precaud
author_rank: Frequent Contributor
timestamp: July 17, 2018, 07:15:00 pm
content: I always preferred the 400F/FL, with its 100uV F.S sensitivity on the lowest range, and switchable 100kHz low-pass filter.
How to decode i2c with oscilloscope hantek dso5102p? - Page 1
Forum section: electronics / testgear

author: yhomer
author_rank: Newbie
timestamp: July 16, 2018, 12:37:32 pm
content: hi friends could you help me, how to configure the oscilloscope hantek dso5102p to decode i2c?

author: evgen.05
author_rank: Regular Contributor
timestamp: July 16, 2018, 05:02:04 pm
content: this Hantek has no any protocol decode function.
Cat II rating for EEVBlog 121GW - Page 1
Forum section: electronics / testgear

author: Medo
author_rank: Regular Contributor
timestamp: July 15, 2018, 06:38:26 pm
content: I don't see Cat II rating for EEVBlog 121GW multimeter. Is Cat II rating even available for it?I know that extrapolating Cat IV based on derating Cat III is a big no-no. How about going to Cat II? Can it be assumed that any Cat III 600V device can handle Cat II 1000V or that assumption is booogus?

author: lypse
author_rank: Contributor
timestamp: July 15, 2018, 08:32:20 pm
content: Datasheet mentions Voltage range up to 600V, I would not use it on 1kV.And what normal applicance would have that high voltage? Old monitors?

author: Fungus
author_rank: Super Contributor
timestamp: July 15, 2018, 09:26:09 pm
content: Quote from: Medo on July 15, 2018, 06:38:26 pmNot true.Quote from: Medo on July 15, 2018, 06:38:26 pmThe trick is to not to raise the voltage.A 600V rated multimeter cannot be used on 1000V, even if it's a lower CAT 1000V.A 600V CAT III multimeter could be a 300V CAT IV multimeter though.
CA6526 Insulation Tester Opened Up - Page 1
Forum section: electronics / testgear

author: threephase
author_rank: Regular Contributor
timestamp: July 15, 2018, 08:55:12 pm
content: For those interested in insulation testers, here are the internals of the Chavin Arnoux CA6526 I purchased a while back.Looks like quite a solid build, although I did find a little solder spatter on one of the boards.
Siglent SSA3000X Trace Store issue in Video Trigger Mode - Page 1
Forum section: electronics / testgear

author: scopeman
author_rank: Frequent Contributor
timestamp: July 11, 2018, 02:13:49 am
content: I have been trying to do a capture/compare of a OOK signal with my SSA3000X. I have the video trigger set at -39dBm and I can capture the signal as Trace "A" and place that in "View" mode. I then selected Trace B in Write mode but when the analyzer triggers it clears the Trace A data display which was "stored" in view mode.So how do I get the instrument to save the "A" trace whilst storing a trace to compare (or is this a bug?).SamW3OHM

author: tautech
author_rank: Super Contributor
timestamp: July 11, 2018, 03:50:29 am
content: Yes it's not entirely intuitive.The button View could be better named as Save as it stops the sweep and fixes the trace.Then open another and select the setting you require; Max or Min hold to compare against the saved trace.Here's a couple of captures as some example.A on 80 MHz span, 40 MHz CF and captured/frozenB on 38-42 MHz span.Video trigger continous running.

author: scopeman
author_rank: Frequent Contributor
timestamp: July 11, 2018, 12:51:42 pm
content: Try to save both A and B and trigger once and save A then trigger again and save B. You can't do it and max or min hold does not do what I want.I am trying to capture a 306MHz wireless ceiling fan controller (much like a garage door opener).As you can see from PNG2 when I trigger from video with trace A in view mode trace B clears trace A even though A was saved in view mode.If I were to use max or min the pulses would not be shown correctly.Sam

author: tautech
author_rank: Super Contributor
timestamp: July 11, 2018, 03:37:16 pm
content: Fairly sure I can do it, I have a 339 MHz garage remote to try it with too but it's the middle of the night so I'll have a go in the morning.What's important for you on this, code and amplitude ?

author: scopeman
author_rank: Frequent Contributor
timestamp: July 11, 2018, 09:40:03 pm
content: Yes that is correct. All of the HP analyzers I have worked with save the trace until set to clear write so I think this is a bug and probably an easily squashable one in the firmware!All the best and thanks for running this down.SamW3OHM

author: tautech
author_rank: Super Contributor
timestamp: July 11, 2018, 10:44:45 pm
content: While the results I've got don't give the same quality as yours the process of storing an A trace and then capturing a B trace does indeed work.....when you work out now. (never done exactly this before)The key is working between Trace and Detect UI's after setting Trigger as required.My workflow:Preset to factory default.Set CF and SpanSet Trigger and LevelView A (capture)Enable B and set to Detect on B

author: scopeman
author_rank: Frequent Contributor
timestamp: July 15, 2018, 04:34:00 pm
content: I will have to try this out the next time (soon) when I get back to it.Thanks,Sam
LeCroy 9350A WPA02 option - Page 1
Forum section: electronics / testgear

author: ciasteczkowypotwor
author_rank: Contributor
timestamp: July 13, 2018, 01:58:38 pm
content: Has anyone installed options WPA01/02/03 from a memory card, or FDD. Maybe someone has the necessary file?Best regardsWojtek

author: Emo
author_rank: Regular Contributor
timestamp: July 13, 2018, 02:22:56 pm
content: Hi WojtejThe Lecroy uses a GAL chip. Fortunately the chip can be programmed yourself or sometimes a seller on ebay does release a batch of them.In the leroy owners group on Yahoo, the chip contents can be downloaded

author: ciasteczkowypotwor
author_rank: Contributor
timestamp: July 13, 2018, 04:52:16 pm
content: You right, it's only firmware update. 39/5000There is no GAL at all, there is an empty stand.

author: scopeman
author_rank: Frequent Contributor
timestamp: July 15, 2018, 04:13:04 pm
content: All of the 93XX, and LC series need a 16V8GAL to enable the WP01/2/3 MC01 and somw other options. I have attached the JED file that you can use to burn into a DIP package 16V8. This GAL will enable all of the useful options on the 93XX series.SamW3OHMModeratorLeCroy Groups on Yahoo! and Groups.io
Size (5mm, 3.5mm, 2.5mm...) of passive probes and price - Page 1
Forum section: electronics / testgear

author: LaurentR
author_rank: Frequent Contributor
timestamp: July 13, 2018, 04:43:24 pm
content: I keep being surprised by the default 5mm probes shipped with modern scopes (most recently for me the ZP03 of the RTB2k). They are all very bulky, heavy and even for the simplest work (probing 0.1" headers), they don't stack well (clips) and exert substantial mechanical force due to their weight. The cheap ones are a pain to position due to their stiff cable. I am having a hard time understanding why standard probes (5mm) are so big?OTOH, I got my hands on (more expensive) 3.5mm Caltest CT3290RA probes (equivalent Tek P6139A) and while their assembly is a bit unusual (clips...), they are small and light and overall just easier to use in all conditions than 5mm probes (they also have a very complete accessory pack available).So my questions to everybody:* Is the bigger size of the default 5mm probes better for anything?* Are they the default probes for new scopes just because they are cheaper to make?* Are they any really nice 5mm probes (better at a price point than 3.5mm or 2.5mm ones)?* Are there any fundamental electrical reasons why 3.5mm or 2.5mm probes are (much) more expensive? I assume it's at the point where manufacturing smaller probes is more expensive, but is there anything electrically more complex (coax size, impedance matching...)?
ITECH 8500+ Series (IT8511+) USB Cable and Software - Page 1
Forum section: electronics / testgear

author: AnotherAlex
author_rank: Newbie
timestamp: April 28, 2018, 10:32:07 pm
content: I just ordered an ITECH 8511+ and am searching for a cheaper USB cable that is known to work with device. Anyone know any working alternatives to the official IT-E122USB communication interface:http://www.itechate.com/en/product/DC_electronic_load/IT8500+.htmI am not sure if something like this would work:https://www.ebay.com/itm/NEW-USB-Communication-Cable-IT-E132-Interface-Kit-FREE-SHIPPING/151940912486?hash=item2360625566:g:ryIAAOxy3NBSe8tFAlso, anyone know of any alternative software packages (e.g BK Precision) that is compatible with this unit? Thanks for your help.

author: BillB
author_rank: Unknown
timestamp: April 28, 2018, 10:40:36 pm
content: I have the ITech 8511+ as well, and use a Maynuo USB/TTL cable:eBay auction: #112542793626All these types of cables will work, just be aware that they'll all probably have a counterfeit FTDI chip, and will require playing driver hokey-pokey depending on your host OS.The 8511+ does support SCPI as well as its native FRAME protocol, so you might have luck with other applications. I just use the horrible ITech software.

author: 1anX
author_rank: Regular Contributor
timestamp: July 14, 2018, 11:26:15 pm
content: Here is a link that shows how to make your own using a TTL to USB and a USB to USB 1000V isolator from Aliexpress.http://www.sensorsiot.org/testing-power-supplies-with-electronic-loads-video-146/