hybridfree/eevblog-posts huggingface dataset:
JTAG Probes and Cell phone flash/unlock boxes - Page 1
Forum section: electronics / testgear

author: Alexei.Polkhanov
author_rank: Frequent Contributor
timestamp: June 06, 2014, 02:47:44 am
content: I was looking for some documentation on cell phone that I found in my junk box and then I found this whole world of "cell phone flash/unlock boxes". Here for example:http://gsmserver.com/software/software.phpand looking at their capabilities I see that many support JTAG programming and NAND flash reprogramming etc. Like this onehttp://gsmserver.com/shop/gsm/riff_box_jtag.php.Does anyone know what are these and how do they work? Are these just cheap, rebranded JTAG probes inside like J-link for example? Given that some have prices from $50 to $120 while J-link (also USB version) is around $500 it could be a nice deal. They all seem to come with specialized software designed for specific phones so I am not sure if any generic dev tools Keil would recognize them. J-link probably higher quality tool anyway but I am still curious.
Unit-T UT61E Capacitance measurements - Page 1
Forum section: electronics / testgear

author: Flump
author_rank: Frequent Contributor
timestamp: June 06, 2014, 12:41:47 am
content: I thought I put some Precision Caps across the UT61E to see how it compared to the quoted specshere are the results.Philips Triplecap value = 10nFmeter reading = 10.064+/- = %0.64cap value = 100nFmeter reading = 100.73nF+/- = %0.73cap value = 1uFmeter reading = 0.9983uF+/- = %0.17Philips Singlecap value = 10uFmeter reading = 9.873uF+/- = %1.27Tetronix Tripplecap value = 1uFmeter reading = 1.0154+/- = %1.54cap value = 100nFmeter reading = 103.03nF+/- = %3.03cap value = 10nFmeter reading = 10.305nF+/- = %3.0415nF @ %1cap value = 15nFmeter reading = 15.086nF+/- = %0.58Here is the link for the 15nF caphttp://www.ebay.co.uk/itm/261187554397?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1439.l2649I dont know what tolerance the Tektronix Cap is.
Extech Customer service  - Page 1
Forum section: electronics / testgear

author: Flump
author_rank: Frequent Contributor
timestamp: June 06, 2014, 01:00:23 pm
content: I bought a new Ex330 multimeter off ebay,just over a month later it developed a faultso the people I contacted first was Extech tosee what to do about a warranty claim.They said contact the seller to see if they couldoffer me a replacement which I did but they couldn't,the seller did offer me a refund even though it wasoutside of his 1 month refund policy.So I contacted Extech again to let them know he could not replace itand they sent me spanky new EX330 which I received todayInteresting to note Flir and Extech are linked somehow as the emails I receivedwhile dealing with this came from a Flir.com email addy.I wont hesitate to recommend them to people in the future.

author: Bored@Work
author_rank: Super Contributor
timestamp: June 06, 2014, 02:08:13 pm
content: Quote from: Flump on June 06, 2014, 01:00:23 pmFlir owns them.
SimChan software for Spirent Signal generator - Page 1
Forum section: electronics / testgear

author: Palmsquirrell
author_rank: Contributor
timestamp: June 05, 2014, 06:20:50 am
content: HelloI have a Spirent GSS6100 signal generator.The unit can be controlled by ATE commands via a IEEE-488 port or with proprietary SimChan software which has a GUI interface.Does anyone know if the SimChan 2.0 software used on the GSS6300 will work with the GSS6100?Anyone know the version of the SimChan software that is used with a GSS6100?Thanks
Newbie:Flir E4-E8: How to test it before purchase? - Page 1
Forum section: electronics / testgear

author: thesi
author_rank: Newbie
timestamp: June 04, 2014, 10:17:57 am
content: How does one test a Flir E4 that is upgraded to E8 before buy?Before I must state, that I am new in thermal photos.- I thought in1. eye-test (see): that is to compare a reference picture with an approved resolution of 320x240 with a test photo of the device, which is made from a commont object (say a hand in 1m distance)Can anyone give me or point me to such a reference picture?2. One needed a program, that gives out the information that the image file of the photo is 320x240. Which program could that be? (I am using Ubuntu)3. test general proper functioning: Do I need to setup a hole environment (kind of flir suite) to check if the main functions are there; as the device could be half broken or beta? Can you give me a list (or some points of) which feature should I check and how to perform that?Thanks in advance. Thanks for any hints.
Another TEK TLA602 resoration - Page 1
Forum section: electronics / testgear

author: BrianM
author_rank: Newbie
timestamp: June 03, 2014, 04:47:12 pm
content: Gentlemen,I have been accumulating information on the TLA602 from the Tek and Intel websites and I was fortunate enough to find this forum.I purchased my 602 from a dealer who had acquired a small batch of them from a nearby university. I have no reason to believe that the machine was not working properly when it was disposed of.I subsequently carried out the usual procedures of dusting the internals and visually checking condition. It looks as though the unit has been well treated.The machine booted under Windows 2000Pro and I have found no faults with it so far. What I would like to do now is to incorporate any worthwhile improvements I can make without getting involved in heroic efforts.Here is the machine spec.From BIOS on setup.BIOS SU81010A.86A.0009.P09 / Celeron 500MHz / Cache 128KB / Memory 512MB (See below).From Application Help.Version 4.4.075.0Original disk drive.Travelstar 12GB (See below)I replaced the original single 64MB RAM card with dual 256MB cards and, as above, the BIOS shows 512MB. I have no idea if the application is actually using the extra memory.I cloned the original hard-drive to a 20GB Travelstar and this is working correctly. The original drive is secured in case of future need.I would appreciate help and opinions as to worthwhile work on this unit. Specifically I would like answers to the two following questions.1. How can I add an SSD drive? I have looked at the Tek website but the information is not very helpful. As above, I have cloned the original drive to a larger IDE version but my progress stopped there. Any attempt to use a larger drive (a 30GB SSD, the smallest I could find) causes a failure on boot. The computer goes through the initial boot process (the black and white progress bar that is labelled "Start Windows") OK. The display changes to the colored "Starting Up" display with the progress bar already containing 9 blocks, then it hangs for a while and displays the BSOD with a message such as "Operating system not found". This occurs whether I completely install Win2000 on the SSD on another computer then put the drive into the TLA or whether I try to install Win2000 with the SSD installed in the TLA itself. It also occurs with an SSD that I have apparently successfully cloned from the operating 20GB hard-drive. Looks like a BIOS change needed.2. Do I need to carry out any immediate life saving procedures such as replacing ROM memory batteries etc/Many thanks,Brian

author: nctnico
author_rank: Super Contributor
timestamp: June 03, 2014, 07:13:23 pm
content: A compact flash card usually works well. You can buy IDE to compact flash adapters on DealExtreme.

author: kc9qvl
author_rank: Regular Contributor
timestamp: June 04, 2014, 01:32:36 am
content: Master slave configuration ? Will the ssd boot on another pc? Drive bootable fdisk and format. As you said bios limitation. Use a Hard drive utility to reduce size of drive.
Fluke 8050A accuracy test - Page 1
Forum section: electronics / testgear

author: KJDS
author_rank: Super Contributor
timestamp: June 04, 2014, 09:03:18 pm
content: I've just found a couple of old Fluke 1050A lurking at the back of the lab so gave them a quick test. One doesn't work but the other is still very accurate. The DC and resistance tests are done with a Fluke 5100B calibrator, that isn't recently calibrated but is still reasonably accurate. The AC tests were done with an old HP calibrator that outputs a little low.

author: KJDS
author_rank: Super Contributor
timestamp: June 04, 2014, 09:06:29 pm
content: more pics

author: KJDS
author_rank: Super Contributor
timestamp: June 04, 2014, 09:07:18 pm
content: and the last few

author: Flump
author_rank: Frequent Contributor
timestamp: June 05, 2014, 01:22:35 am
content: nice things to find in your lab!let me be your lab cleanerI have an 8010a and 8060aand they impress the hell out of me.I use a 5v dc ref which is accurate to %0.05for resistance I use 100k@%0.1 and 620R@%0.1 resistorsand both of the flukes are spot on.
Measuring Transient voltage tolerence - Page 1
Forum section: electronics / testgear

author: jpradeeban
author_rank: Newbie
timestamp: June 03, 2014, 04:09:36 am
content: Dear Experts,one of my customer asked for my GPS product's energy let through or transient voltage tolerance. he is actually asking for the tolerance value when the module is tested to IEC 801-4 spec for fast transients. His main objective is to update his lightning protection system, and he wants to evaluate surge arrestor let-through energies against the Module.My question is since i do not prefer to do the IEC standard test, which is costly, is there is a simple way or method to estimate this tolerance value in the lab?if yes, please guide me, how to perform the test and measurement.Appreciate your support.Thanks.

author: T3sl4co1l
author_rank: Super Contributor
timestamp: June 03, 2014, 08:22:16 am
content: If your customer requires a particular standard, and you cannot provide that standard, he cannot use your product. Period.Tim

author: Jeroen3
author_rank: Super Contributor
timestamp: June 03, 2014, 12:36:40 pm
content: Bad things happen if the customer tests your product and your product does not meet the standard.But if you used some off-the-shelf power module, you can derive specs from there.
About FLUKE I2500 - Currnet Probe (Rogoswki coil) - Page 1
Forum section: electronics / testgear

author: georgd
author_rank: Regular Contributor
timestamp: June 03, 2014, 06:29:49 am
content: Is anybody know the probe mentioned in subject contain active electronic?Third tiny leg on its connector is supply pin or simply for polarization and misuse prevention?
DS1074Z zoom bug? - Page 1
Forum section: electronics / testgear

author: mayor
author_rank: Regular Contributor
timestamp: May 31, 2014, 01:43:22 am
content: I have a square waveform, which appears fine until I zoom in below 200mV. Has anyone else seen this? The attached shows 500mV/div, but the odd one is after zooming in to 200mV and stopping capture, then going back to 500, for comparison to the running 500.Anyone?

author: Hydrawerk
author_rank: Super Contributor
timestamp: May 31, 2014, 02:04:12 am
content: I am not sure but isn't this caused by oscilloscope overdrive? This is a common problem or feature of most scopes.http://cp.literature.agilent.com/litweb/pdf/5989-0068EN.pdf

author: mayor
author_rank: Regular Contributor
timestamp: May 31, 2014, 09:01:31 am
content: Quote from: Hydrawerk on May 31, 2014, 02:04:12 am...thanks.

author: jimjam
author_rank: Regular Contributor
timestamp: June 02, 2014, 05:19:44 pm
content: How are you liking the DS1074Z so far?

author: max666
author_rank: Frequent Contributor
timestamp: June 02, 2014, 06:44:12 pm
content: I tried to reproduce your waveform on my DS1074Z, but wasn't able to get that result. I'm happy to try again, if you can provide more detail on what exactly you do, to get that waveform.But I'm inclined to agree with Hydrawerk, I too think this feature might be caused by overdrive.EDIT: Although you're looking at a 1.15kHz signal, so recovery time should be way quicker than what we see. Maybe it is a zoom bug.

author: tom66
author_rank: Super Contributor
timestamp: June 02, 2014, 09:27:34 pm
content: This isn't a bug, and it happens with many oscilloscopes. By setting the gain that high, you are overdriving the input amplifier so it behaves poorly. It's not harmful but can cause confusing results. There was a thread about this on the 2000X Agilents too, iirc.

author: alexwhittemore
author_rank: Frequent Contributor
timestamp: June 03, 2014, 06:36:16 am
content: I tried to reproduce this too but had no luck. If anyone comes across a set of conditions that seems repeatable, I'd love to hear about it.
Fluke 117C vs Sanwa PC710 vs UNI-T 71D - Page 1
Forum section: electronics / testgear

author: arshavir
author_rank: Newbie
timestamp: June 09, 2014, 07:29:57 pm
content: Hi forum,I want to buy a multimeter and after googling a bit stuck with following 3 multimeters:1. Fluke 117C2. Sanwa PC7103. Uni-t 71DCan you please help to chose the proper multimeter.From the price point of view UNIT looks the best.I am hobbyist and used the cheapest chinese DMMs in the past, but want to but more reliably, functional and precise one.

author: arshavir
author_rank: Newbie
timestamp: June 09, 2014, 07:37:45 pm
content: Just noticed that all 3 models has numbers "1" and "7"-117,710 and71.

author: dp
author_rank: Contributor
timestamp: June 09, 2014, 09:20:27 pm
content: Quote from: arshavir on June 09, 2014, 07:29:57 pmFluke 117 can't do microamps. If this is relevant for you, consider the model 17b or the 175-177 series instead.QuoteMany people on this forum object to the build quality of the UNI-T 71 series.QuoteIt depends on your priorities. If reliability, safety and build quality are more important, go for a Fluke. If you prefer functionality, any of the other two.

author: arshavir
author_rank: Newbie
timestamp: June 10, 2014, 06:53:28 am
content: Thanks.What about Sanwa build quality and reliability?Per my understanding it should have comparable to Fluke quality and safety.

author: Wytnucls
author_rank: Super Contributor
timestamp: June 10, 2014, 10:48:02 am
content: 71D, cheap, reliable and full featured for electronics work, but slow continuity and low on input protection.PC710, expensive for a 10,000 count meter, no internal logging and low battery life.117C, low resolution, low bandwidth, missing features and no PC connection.

author: Creep
author_rank: Regular Contributor
timestamp: June 10, 2014, 11:05:53 am
content: I feel like for the price you should probably have a look at the Byrmen BM869. Plenty of info here in the forums and everybody seems very pleased with their purchase when it comes to the BM869. IIRC Dave also did a quick review of it some time ago.

author: Wytnucls
author_rank: Super Contributor
timestamp: June 10, 2014, 12:03:09 pm
content: In the 300$ range, the Brymen BM869 has better specs than the Sanwa PC710. It doesn't come with internal logging either though and the PC kit costs extra too.The 71D has most of everything a hobbyist would want for electronics, costs far less and has a more stable voltage reference than the Brymen BM869 or Sanwa PC7000 to boot. (5ppm/C versus 10ppm/C)

author: arshavir
author_rank: Newbie
timestamp: June 12, 2014, 10:04:20 am
content: Thank you very much for feedbacks.I am mostly inclined to buy Sanwa PC710 - do you have idea how I can distinguish counterfeits from original?We don't have representative in our country, so will buy it from unknown sources or from online stores.Regards,Arshavir
Fluke 87-V  - Page 1
Forum section: electronics / testgear

author: Wmacky
author_rank: Regular Contributor
timestamp: May 31, 2014, 06:21:33 pm
content: I see these are on sale around the web, and would like to pick one up. So what is the chance of Fluke releasing the "ALL NEW Updated" 87 1 day after a finally pick one of these puppies up!?!

author: austere
author_rank: Contributor
timestamp: May 31, 2014, 06:33:06 pm
content: Do you mean discounted or available for purchase?I'm in the market for one as well, Australian prices are set at a disgusting mark up level.Anyway, I'd just pick one up, multimeter technology advances at a slow pace and after that GSM problem you may as well get one that you know will work for sure rather than a new untested model.

author: Wmacky
author_rank: Regular Contributor
timestamp: May 31, 2014, 07:18:03 pm
content: I meant discounted. $359 on Amazon.

author: FrankenPC
author_rank: Unknown
timestamp: May 31, 2014, 07:32:35 pm
content: Quote from: Wmacky on May 31, 2014, 07:18:03 pmWhat country do you live in? In the US Tequipment.net has them for 359$. We get 6% off using an EEVBLOG discount code. Email Tequipment about it.

author: Wmacky
author_rank: Regular Contributor
timestamp: June 02, 2014, 06:48:15 pm
content: Thanks!OK, I've got the EEVblog Code, But darn if I can find the box to enter it during checkout?

author: FrankenPC
author_rank: Unknown
timestamp: June 02, 2014, 07:06:02 pm
content: Quote from: Wmacky on June 02, 2014, 06:48:15 pmIt should be towards the end of the checkout process.

author: Wmacky
author_rank: Regular Contributor
timestamp: June 02, 2014, 11:21:29 pm
content: Nope not there! I go to the cart, select shipping then click on Paypal. It goes to paypal for me to pay. No discount box?

author: Wmacky
author_rank: Regular Contributor
timestamp: June 02, 2014, 11:35:57 pm
content: Never mind. I found that I had to sign up for an account to get the discount instead of using the quick Paypal checkout!What a deal though. 87/V on sale for $359, + A free generic case, then an additional $ off for EEV! Finally getting a 87 !!!! Got it for $338 shipped with a case. My current meter is a Sears only version Fluke, which I love BTW!
HP54621a noise ? - Page 1
Forum section: electronics / testgear

author: inoxidabile
author_rank: Newbie
timestamp: June 03, 2014, 06:19:36 am
content: Hi everybody !I'm new in this forum so, once again, a great "Hello" to all!OK, I 'd like to describe my problem: I bought an used HP54621a, it seems fine but sometimes, randomly, the traces shows an increase of thickness and a sort of "noise"...It doesn't disappear even if the channels are selected on GND, no probes connected, the acquisition is set for Average/4, 8, 16 or more and BW limit.The amplitude of this "noise" can be up to 0.2 - 0.3/div.Moreover, it happens only in certain positions, when I move the offset of trace(s) and if I move it just a little down or up it becomes lower or disappear.Of course, I did the update of software (latest release from HP site), the self test and the user cal from the Service menu, without results.The manuals (User and Services) have no indications about.OK, I can understand that, maybe, I'm just across a quantization value (+/- 1/256th can become visible on screen) but not so high... In the attached files there are two screenshots print (normal and average) and, please, believe me I've seen up to double of that shown and also with average/16...Now, when I use the scope I always ask to myself: is it a true visualization or that "noise"?I'm very sad for this because I searched a lot for this scope and now I can't buy an other one...Then, any help or suggestion would be very very appreciated.Thank in advance to everyone.
Buying my first oscilloscope soon, DS1000Z VS DS2000A VS DS1000B - Page 1
Forum section: electronics / testgear

author: asgard20032
author_rank: Regular Contributor
timestamp: June 02, 2014, 03:15:10 am
content: Buying my first oscilloscope soon, DS1000Z VS DS2000A VS DS1000B...Can someone help me found out what are the plus and minus of each of them... (not sure about the DS1000B).Also, I live in canada, anyone here know where I may buy one? I heard tequipement give a special discount here, but does they chip for free in canada? If not, how may i buy one?

author: echen1024
author_rank: Super Contributor
timestamp: June 02, 2014, 05:03:53 am
content: Eliminate the DS1000B first. That is overpriced and is very old. It really depends on what you need it for. I have done some videos on the DS1000Z, but some general pros/cons are outlined below:DS1kZ:pros: 4 channels, cheapercons: less BW, less features, smaller screenDS2kpros: Larger screen, up to 300MHz, 50ohm, higher wfms/s, more intensity levels, more memory (56mpts vs 24), waveform playback knobcons: only 2 channels, more expensiveit ultimately boils down to what the scope will be used for. If you plan on doing a lot of pure digital, wih serial decode necessary, a DS1000Z would be good for you, plus it's $300 cheaper. If you are doing general purpose analog work, the DS2000 with it's suprtior specs might be better. Just ask: Do I need the 4 channels?

author: asgard20032
author_rank: Regular Contributor
timestamp: June 02, 2014, 10:28:29 am
content: But spi require at least 3 channel(clk, MISO or MOSI and CS)... And i tought that the ds2000 was more for digital, and 1000z was more analog...

author: idpromnut
author_rank: Unknown
timestamp: June 02, 2014, 11:32:15 am
content: Hi! I have the DS2072A and do SPI debugging. What I have realized is that typically for decode the 'scope isn't all that great a tool for the job if you are really spending time probing what's going on and trying to decode an unknown protocol. Here a dedicated USB logic analyzer will be better I have found. Where the 'scope decode really shines is when you are trying to debug a SPI/I2C/RS232 signal and the signal itself is the problem, and not the contents of the encoded serial stream. Then, yes, perhaps having more channels would be easier, but I have so far been able to get by with 2 (scoping, for example, the clock and MOSI lines, then the clock and MISO lines if I have just a single SPI device).

author: tom66
author_rank: Super Contributor
timestamp: June 02, 2014, 11:37:48 am
content: Quote from: asgard20032 on June 02, 2014, 10:28:29 amThat's the issue with the DS2000 for SPI, you can only see one side of the conversation. Master to slave or slave to master. So no analysis of a transaction involving a register pointer write, then reading data back.With the DS1000Z, I was able to debug an I2C DAC. I could see the I2C data being sent on two channels, then shortly after the change in output voltage of the DAC. Incredibly useful to have those extra channels, even for 2-wire serial.
HP 3478A Issue - Page 1
Forum section: electronics / testgear

author: echen1024
author_rank: Super Contributor
timestamp: June 02, 2014, 04:59:09 am
content: Hello,So it's been 2-3 months after I changed the battery in my HP 3478A, and all went quite well. I tried to use it again today, and there is a problem on the lowest range in 2W ohms. First of all, it displays UNCAL, which is funny since all the other ranges don't display that and are in spec, however, when I try and cal it, it requires the upper and lower limits. When I short the 2 inputs, it gives 10ohms, so it attempts to cal that as 10ohms thus making 0 impossible and the lowest range useless. All other ranges are perfectly fine.

author: Dr. Frank
author_rank: Super Contributor
timestamp: June 02, 2014, 06:10:38 am
content: Hello,that sounds familiar to me, me and several other people had similar problems on a 34401A.https://www.eevblog.com/forum/testgear/hpagilentkeysight-34401a-2w-problem/Check the following:Is 4W Ohm on the same, lowest range ok?Switch to the rear panel, and check that same 2W range using the rear input jacks.First check zero Ohm, then with a known good resistor.Is the reading OK on the back jack?Switch to front again, maybe the 10 Ohm reading with a short changes in magnitude.My idea is, that switch S1 is faulty / dirty, as described in this thread about the 34401A.Otherwise check the other components in the 2W input circuitry.Frank

author: alexwhittemore
author_rank: Frequent Contributor
timestamp: June 02, 2014, 07:34:19 am
content: I definitely noticed on my own that the 2W ohms measurement seemed off. The 4W measuring the same shunt was dead on (forget the reading, but reasonable for a couple of good contacts and a short bit of copper), so I assumed the meter's contacts were a bit dirty. I used a Q-tip chucked up in my drill (well, a bunch of them) to clean a surprising amount of oxidization out of the terminals (all of them, actually), but that only fixed maybe 25% of the problem. I took the cover off to measure contact resistance with a second meter and found that a bunch of the wire->terminal joints were high resistance, sometimes as bad as one or two ohms. Hitting them with some contact cleaner (yeah, deoxit) and unplugging/plugging them back in a few times took care of the problem.
Need your thoughts on hardware USB analyzers. - Page 1
Forum section: electronics / testgear

author: SparkMasterFlash
author_rank: Newbie
timestamp: May 31, 2014, 11:11:46 pm
content: Hi,I'm thinking about picking up a Teledyne LeCroy Mecury T2 USB Analyzer for an upcoming project.http://teledynelecroy.com/protocolanalyzer/protocoloverview.aspx?seriesid=414&capid=103&mid=511I was wondering if anyone around here has used one and has any comments.I am mostly going to be using it for debugging a stereo audio interface, and for understanding how existing audio interfaces work. Turns out that USB audio is actually pretty complicated.I could probably get by with a software analyzer if it wasn't for the fact that I need to write drivers for both Mac and PC platforms, and also to test my "USB To Go" code (which doesn't involve a computer).Thoughts? Experiences? Recommendations for a different device?Thanks!

author: nctnico
author_rank: Super Contributor
timestamp: June 01, 2014, 12:50:33 am
content: Why would you want to write drivers? AFAIK audio is standarised so if you device adheres to those standards the OS already has the proper drivers. Writing a USB driver for Windows is not something you would want to do.Did you look at the 'Beagle' USB analysers? (No, I'm not referring to a Beagle board).

author: SparkMasterFlash
author_rank: Newbie
timestamp: June 01, 2014, 01:31:07 am
content: Quote from: nctnico on June 01, 2014, 12:50:33 amWindows does not support the Asynchronous Isochronous mode for USB Audio 2.0. This mode is needed if you want the device's word clock to be the master clock. Without this, the device must either adjust it's word clock to match the rate at which the computer is sending samples, or perform a sample rate conversion, neither of which is good for high quality audio.At least that is my understanding. I'm still feeling my way through these USB issues.I did look at the beagle analyzers. I really can't seem to find reviews on any of the USB analyzers. In the absence of any unbiased information, I'm inclined to go with the trusted brand name.

author: mazurov
author_rank: Frequent Contributor
timestamp: June 01, 2014, 02:59:26 am
content: I have been using Beagle 480 for about 5 years. It works well for debugging, not so well for RE (you'd have to code your own filters to sift through raw captures). That's the only analyzer I ever used though, others could be even worse.

author: SparkMasterFlash
author_rank: Newbie
timestamp: June 01, 2014, 03:18:41 am
content: Quote from: mazurov on June 01, 2014, 02:59:26 amThanks for the data point. Possibly I'm being dense, what is "RE"?EDIT: Reverse Engineering?
Topward digital function generator 8112 - Page 1
Forum section: electronics / testgear

author: Simon
author_rank: Unknown
timestamp: May 30, 2014, 09:46:26 pm
content: I bought this function generator but I'm not sure if it's working right. There is a ramp/pulse knob that if you turn effectively alters the duty so for example a triangle wave becomes a sawtooth wave. but it also seems to mean that the frequency goes down to about 10% of what it was, surely the wave frequency should stay the same.

author: SeanB
author_rank: Super Contributor
timestamp: May 31, 2014, 06:13:05 am
content: Not necessarily, the ramp function often alters a charge or discharge current source, and this alters frequency as well. Common flaw in many function generators that use the same basic chipset or a clone thereof.

author: Simon
author_rank: Unknown
timestamp: May 31, 2014, 07:21:24 am
content: ok just making sure it works as I got it second hand off ebay. It does the same for sine and square wave. At the top of the range the square is really rounded to the point it looks like a charge/discharge curve on a capacitor and is not really going to be usable without being squared up properly by another output stage like a comparator or logic gate but then I'd loose any offset voltage.
Maynuo eload speed tests - Page 1
Forum section: electronics / testgear

author: Harvs
author_rank: Super Contributor
timestamp: May 28, 2014, 11:59:14 am
content: Posting this here incase anyone is interested.Someone on another forum asked me about the max update speed for the Maynuo electronic load, so I wrote a couple more test scripts for the library:https://github.com/harvie256/MaynuoPyAnywho, results were a max update rate of 125 updates/sec.Chanel 1 below is the current output on the back of the Maynuo, and channel 2 is the 115200 serial line.Speed test is changing from 1A to 2A square wave.

author: HighVoltage
author_rank: Super Contributor
timestamp: May 29, 2014, 12:53:03 pm
content: That is a nice test you did.I just tested a buck converter with the Maynuo, 12V input, 18V output at up to 15ADuring the test, I went up to 50 updates/sec. and was surprised, how stable the Maynuo was.Absolutely amazing!In contrast, I also have a BK-Precision eload and that one was only stable up to 10A.And the BK-Precision instrument was twice as much $$

author: Harvs
author_rank: Super Contributor
timestamp: May 30, 2014, 12:21:16 am
content: Quote from: HighVoltage on May 29, 2014, 12:53:03 pmReally, as in the 8500? Surprises me that there's much difference, I thought they were pretty much the same hardware?I'm interested in what conditions it was unstable under. Generally speak for a CC load to become unstable it needs a source with a lot of series inductance such as long connecting cables.

author: saturation
author_rank: Super Contributor
timestamp: May 30, 2014, 02:00:48 pm
content: Eloads working with high amps will tend to oscillate. Keeping leads shortest and placing a rated capacitor on the input will change the RLC relationship and usually fixes the problem.

author: Harvs
author_rank: Super Contributor
timestamp: May 31, 2014, 02:56:44 am
content: Quote from: saturation on May 30, 2014, 02:00:48 pmI take it one step further and have some cap and resistors setup to do this. Just low value resistors, like 100mOhm, in series with a few uF cap works wonders as a snubber.
Is $2400 for a USED Agilent DSOX2024A with all options a good price? - Page 1
Forum section: electronics / testgear

author: TransistWHORE
author_rank: Newbie
timestamp: May 30, 2014, 07:48:12 pm
content: It's like the title says. It's about $1800 without options, but I'm going to pay $500 for the licensed software bundle. What do you guys think?I'm using this for power supply design/modeling/testing. I need a higher quality scope because my current scope completely misses critical details about switching waveforms, such as 2V pk-pk switching transients on a 28V bus.

author: austere
author_rank: Contributor
timestamp: May 30, 2014, 11:50:48 pm
content: I'm guessing this isn't brand new because that's an excellent price if it is!Out of interest, which oscilloscope are you currently using?
Bench Test Cables - Page 1
Forum section: electronics / testgear

author: Dawn
author_rank: Regular Contributor
timestamp: May 29, 2014, 04:14:56 am
content: Traditionally I've centered all my bench test cables around rg 142 b/u with BNC females on both ends for communications up to 800 mc. I'm planning to work higher and looking to buy sets of cables hopefully from chinese suppliers cheaper then I can make myself with locally sourced LMR that will require pneumatic crimping at prices that I'd rather not pay. The chinese market seems to have a LMR type equivalent that I'm not familiar with. I'm just looking for rg/58/reg-214 sized jumpers around 3' and want to know what some of your folks are using. I don't plan to work any higher then 2 gc and want to find an economical source for a handfull of cables for my bench. Any suggestions ?

author: VK5RC
author_rank: Unknown
timestamp: May 29, 2014, 06:34:47 am
content: BNC at 2GHz if I understand correctly is a long stretch! I tend to limit BNC to 500 MHz, if absolute performance not critical but when you are using a cable you are trying to measure something. I spent a whole day mucking around until I worked out a cable in the middle of my setup was no good, it tested fine at DC. I would tend to go for quality and home made but really test them out first. The ebay store rf-parts has supplied me with reasonable price coax and connectors before.

author: KJDS
author_rank: Super Contributor
timestamp: May 29, 2014, 07:51:47 am
content: Good RF accuracy and longevity from cables is easy if you don't want any flex in the cable. From memory LMR is stiff, but I checked the website and it seems that LMR 100 is quite flexible, but a 1m length will have over 1dB of loss at 2GHz. It's not only bend radius that needs considering, it's also how much spring is in the cable, nothing worse than connecting a circuit to a cable, letting it go and having the cable ping it across the bench.If you're in the UK, or EU, these people make cables well at a sensible price.http://www.gigatronix.co.uk/default.php?_minc=homeAlternatively, scour ebay for Sucoflex or Gore cables

author: Steffen
author_rank: Regular Contributor
timestamp: May 29, 2014, 10:18:02 am
content: Traditionally BNC connectors are limited to 1 GHz. LMR195UF is as large as RG58 cable and it's quite flexible. Good, but stiff cable is SS402 by Harbour Industries. Usually I use SMA or N connectors above 1 GHz. Mostly for applications around 1,3 GHz.

author: Dawn
author_rank: Regular Contributor
timestamp: May 30, 2014, 03:20:20 pm
content: Sorry for the brain glitch folks. I meant RG-142 not RG-213 for bench setups. Many of the Chinese vendors are selling relatively inexpensive jumpers made of LMR-195 in N, BNC, and others. Far cheaper then making up jumpers myself out of 142, connectors, and probably much more flexible. Some list another '195 designation that I assume is a clone. Any experience with these products? Typically you get what you pay for, but I have to admit that I've been very pleasantly surprised with most all my parts and connector purchases and the wait is definitely worth the money saved if you're in no hurry.
Rigol DS2202 vs DS2202A - Page 1
Forum section: electronics / testgear

author: vopt
author_rank: Newbie
timestamp: May 28, 2014, 10:32:40 pm
content: Hi All,Does anyone know what the difference between these models is? I can't find any difference in the specs, but the DS2202 is slightly cheaper. Is there any reason to go for the A model?Thanks in advanceDave

author: Dave
author_rank: Super Contributor
timestamp: May 29, 2014, 02:48:31 am
content: AFAIK, the A model also offers a switchable 50 ohm termination on the inputs.

author: sotos
author_rank: Frequent Contributor
timestamp: May 29, 2014, 02:54:52 am
content: 1. Think that DS2202 is getting out of production. The new ones will be the DS2202A.2. Input impedance, switchable 1 M? - 50 ?.

author: vopt
author_rank: Newbie
timestamp: May 29, 2014, 11:27:57 pm
content: Thanks for the info guys. I opted to save a few bucks and put on a 50 ohm termination when I need it (which is almost never)Great forum here.Dave
siglent easy wave softwere visa32.dll error - Page 1
Forum section: electronics / testgear

author: electronics man
author_rank: Frequent Contributor
timestamp: May 28, 2014, 08:32:44 pm
content: I was trying to download the siglent EasyWave softwere from the disc that came with my siglent sdg800, when I install it comes up with an error "visa32.dll missing from your computer" my computer is running windows 7. any ideas?

author: bimj1
author_rank: Newbie
timestamp: May 28, 2014, 08:38:56 pm
content: You need to download and install the visa runtimehttp://www.ni.com/download/ni-visa-run-time-engine-5.4/4231/en/You will have to register but from there its free to download

author: electronics man
author_rank: Frequent Contributor
timestamp: May 28, 2014, 08:55:14 pm
content: yeah it worked thanks

author: tautech
author_rank: Super Contributor
timestamp: May 28, 2014, 09:11:01 pm
content: In the CD supplied in the Easywave folder go to "helpfiles" and open Help_EN.chm and in Overview/Config you will see configuration requirements including a link for NI-VISAhttp://www.ni.com/visa
MDO4104B-6 - Page 1
Forum section: electronics / testgear

author: BalticLab
author_rank: Regular Contributor
timestamp: May 27, 2014, 09:33:04 pm
content: Quick overview of the Tektronix MDO4104B-6. Also showing how to properly calibrate the passive probes and showing how to transfer a license from an option module into the scope. The latter is great for people concerned about theft of their option modules.

author: Carrington
author_rank: Super Contributor
timestamp: May 27, 2014, 10:24:06 pm
content: Hi!Just one bothering question:It is another gift from Tek?

author: BalticLab
author_rank: Regular Contributor
timestamp: May 28, 2014, 12:49:07 am
content: Yes, it is a gift from Tek. But it's an exclusive gift. They gave away a bunch of the MDO3000 and they gave me a MDO4000B to show off.

author: Carrington
author_rank: Super Contributor
timestamp: May 28, 2014, 05:36:50 pm
content: They say the best things in life are free.
Waveform Update Rate Digital vs Analog (DS2000  vs Tek 2465) - Page 1
Forum section: electronics / testgear

author: KedasProbe
author_rank: Frequent Contributor
timestamp: June 01, 2014, 01:59:59 pm
content: HiI couldn't find much info about the blind time and update rate of analog scopes and how they compare to the latest digital scopes with Max. >100kHz waverform updates.In summary of this measurement I would say:-This analog scope kept going until 1µs/div while the DS2000 starts breaking down earlier at 20µs/div.-This analog scope has a max. of 511kHz waveform updates, that is less than the new one from Agilent with 1000kHz. (The DS2000 has a max. of 50kHz 1/10 of the Analog one)So it would be interesting to add an 1000kHz Digital Scope to this graph.-This analog scope is setup so the blind time in never getting close to 0% (sweep of 12 div, 10.2 div visible)Notes:About the DS2000:The waveform update rate is from the excel file from marmad. (smallest memory depth)About the Tektronix 2465:The blind time of 14% is about 1.8 divisions, or with other words one division left and one right of the screen (visible part is 10.2div)

author: SAUL BRITTO
author_rank: Frequent Contributor
timestamp: June 02, 2014, 02:24:28 am
content: You want to know what is a "digital" scope,go to XY mode... AARRRGHH!!
Creating and Altering Masks to Search Frames on the Rigol DS2000 / DS4000 - Page 1
Forum section: electronics / testgear

author: Pinkus
author_rank: Frequent Contributor
timestamp: May 26, 2014, 07:46:49 am
content: VERY cool!Well done. Thank you!

author: marmad
author_rank: Super Contributor
timestamp: May 26, 2014, 09:30:58 am
content: Quote from: Pinkus on May 26, 2014, 07:46:49 amYou're welcome, Pinkus - and thanks!

author: Harvs
author_rank: Super Contributor
timestamp: May 26, 2014, 09:48:14 am
content: Cool mate, a technique I hadn't considered before.Should be pretty easy to write a program to graphically edit those masks as well. Format is pretty simple.Let me know if you're not going to get around to doing it in RUU as I could probably find the time next month.

author: marmad
author_rank: Super Contributor
timestamp: May 26, 2014, 08:30:04 pm
content: Quote from: Harvs on May 26, 2014, 09:48:14 amThanks, Harvs. If I don't get around to it in the coming month, feel free to have a go at it.

author: Carrington
author_rank: Super Contributor
timestamp: May 26, 2014, 08:44:08 pm
content: Brilliant!

author: marmad
author_rank: Super Contributor
timestamp: May 27, 2014, 01:53:30 pm
content: Quote from: Carrington on May 26, 2014, 08:44:08 pmThanks, Carrington!

author: Mark_O
author_rank: Frequent Contributor
timestamp: May 27, 2014, 10:29:21 pm
content: Quote from: marmad on May 25, 2014, 11:22:05 amThat's a clever technique, Mark. Though a fair amount of work. I'm assuming that selecting MaskRange/CursorRegion doesn't work? I.e., using cursors to select the sub-region to mask also shrinks the acquisition interval as well?

author: marmad
author_rank: Super Contributor
timestamp: May 27, 2014, 11:32:53 pm
content: Quote from: Mark_O on May 27, 2014, 10:29:21 pmThis particular search could have been done by changing the mask range (once a match/mask was located), but many types of masks (and thus searches) could not. The Mask Range feature is a very simple modifier of a mask. Much of the point of the video was to show the format of mask files and how to manually edit them.And a fair amount of work? Doesn't really seem so to me - but I guess it depends on your idea of work. It certainly takes me a lot less time then scrolling through hundreds or thousands of frames. And if you work with the same protocol a lot (as I do), you can create universal masks (as I have) to use over and over again.

author: SPRX
author_rank: Regular Contributor
timestamp: May 28, 2014, 12:48:22 am
content: Good one Marmad !!Awesome !

author: H.O
author_rank: Frequent Contributor
timestamp: May 28, 2014, 05:40:10 am
content: Yes, excellent advice and an excellent video! Thanks for showing it!Now, if only Rigol would fix the DS4k firmware so that the decoder works on recorded frames I might be able to use it! It's been fixed on the DS2k for quite some time now (months) but the DS4k is still broken in that regard.
Tektronix 2213 or Tektronix 2235 - Page 1
Forum section: electronics / testgear

author: geekbot
author_rank: Contributor
timestamp: May 25, 2014, 01:31:05 pm
content: I can get the Tektronix 2213 for 150$ with 1 year warranty provided by the seller or a Tektronix 2235 for 210$ with no warranty. The 2235 is a newer model with lot more features and more bandwidth. I am just a beginner and this is my first test equipment other than a cheap ass multimeter. Should I save more and get the 2235?

author: GreyWoolfe
author_rank: Unknown
timestamp: May 25, 2014, 03:30:53 pm
content: Yes, save and get the 2235. I have one and it is a nice scope.

author: geekbot
author_rank: Contributor
timestamp: May 27, 2014, 06:52:02 pm
content: Quote from: GreyWoolfe on May 25, 2014, 03:30:53 pmSadly 2235 is sold out! Going to get the 2213

author: grumpydoc
author_rank: Super Contributor
timestamp: May 27, 2014, 07:00:33 pm
content: QuoteIf you were thinking of a $200 budget it should be easy enough to find a 2235 on ebay

author: geekbot
author_rank: Contributor
timestamp: May 27, 2014, 07:11:09 pm
content: Not in my country! Shipping will cost more than the scope itself! And Tek scopes are so rare in India!

author: grumpydoc
author_rank: Super Contributor
timestamp: May 27, 2014, 07:21:30 pm
content: It is worth setting your location in your profile so that we can tell what country you are in - it often makes a difference in the advice that people give, especially for purchasing.
Why do Gossen spec their DMMs at +/- 2K and how best to compare to say Fluke? - Page 1
Forum section: electronics / testgear

author: jpb
author_rank: Super Contributor
timestamp: May 26, 2014, 12:13:47 pm
content: There seems to be a general consensus on these forums that Gossen make very nice meters and I want one!I'm thinking of getting one rather than a second 5 1/2 digit bench dmm.In particular I've been looking at the Gossen metraHIT Ultra which is 310k count and has a headline basic dc error of 0.02% which makes it in the same ball park as a 5 1/2 digit bench meter (typically 0.015% to 0.02%) and also the top of the range Fluke at around 0.025%.I then noticed that whereas everyone else specs for 23C +/- 5K, Gossen spec over the much narrower range of 23C +/- 2K. They also give figures per /10K deviation from this range.If I adjust the figures by simply multiplying the 10K deviation by 3/10 (to allow for the extra 3K) then the error on the Gossen nearly doubles to 0.035%.Is this correct? I know that temperature effects are not linear so it maybe that the +/- 5K figures are much closer to the +/- 2K figures than my naive calculation suggests.I would be using this meter mainly (almost exclusively) in my "lab" where the temperature, coincidentally is exactly 23C today (as measured on my highly inaccurate digital thermometer/hygrometer) but I would estimate the temperature range is probably likely to be closer to +/- 5K rather than +/- 2K as my room is not airconditioned.I realise that the Gossen, even at 0.035% has very good specs for a handheld DMM, but the mean error (including range related terms) is around 0.053% compared to 0.017% for my existing Advantest 7451A bench multimeter, so I couldn't really use the Gossen to check on drift on my Advantest which I'd like to be able to do. (One less "reason" to persuade myself that buying the Gossen would be "sensible"!)
Fluke 189 buzzer acting strange? - Page 1
Forum section: electronics / testgear

author: petieken
author_rank: Contributor
timestamp: May 25, 2014, 05:13:59 pm
content: Hello everyone, this is my first post here on the eevblog forum. I've been watching the episodes for quite a while.I just got my first fluke DMM from ebay. Everything seems to work fine, some basic measurements seems consistent with my other cheapo multimeters.Only weird thing is the buzzer, when I plug a lead in the A/mA sockets when in volt mode I get a pulsing beep, only a couple of hz I guess. I looked this up in the manual and it seems normal to make a "chirping sound". When I switch to continuity test and hold the probes together I also get a pulsing beep but at a higher frequency. It's pretty stable though, there are no irregularities or frequency variations, at least to my ear.I expected a continuous beep like I have seen in many of Dave's Fluke multimeter reviews...Can someone with a Fluke 189 (or 187 perhaps?) confirm what sound it's supposed to make in continuity mode? I'm suspecting my ebay special has a fault...Thanks

author: paul
author_rank: Contributor
timestamp: May 25, 2014, 09:59:58 pm
content: Thats normal for the 189, its to warn you that you have your probes connected to measure current and the meter set to measure voltage.It stops you from blowing fuses, or worseAnd yes the diode and continuity test `chirp` (much nicer than a beep).Paul.

author: petieken
author_rank: Contributor
timestamp: May 26, 2014, 09:13:42 am
content: Ok thanks, seems I got a good deal after all.The manual mentioned 'chirping' when the leads are plugged in wrong, no worries. But for continuity mode the manual just says 'beeping', so I was expecting a continuous beep.Anyway, I'm glad there's nothing wrong with the meter. Thanks for the reply!