hybridfree/eevblog-posts huggingface dataset:
Rebranding of Bench Power Supplies - Page 1
Forum section: electronics / testgear

author: Evan.Cornell
author_rank: Regular Contributor
timestamp: March 29, 2018, 02:45:08 pm
content: I just got an email from Newark advertising Extech 382275:http://www.newark.com/extech-instruments/382275/bench-power-supply-30v-600w/dp/55R0895?CMP=e-email-Promo-290318-NA-Extech&et_cid=29903226&et_rid=1451780574&cmp=This looks awfully similar to B&K Precision 1685B Series:http://www.bkprecision.com/products/power-supplies/1688B-1-18v-0-20a-dc-power-supply.htmlDoes anyone know who actually designs/makes these models?

author: Candid
author_rank: Regular Contributor
timestamp: March 29, 2018, 07:05:31 pm
content: As far as I know Manson is the OEM:http://www.manson.com.hk/products/detail/154

author: beanflying
author_rank: Super Contributor
timestamp: March 30, 2018, 12:11:24 am
content: Yep Manson rebadge for a lot of others. I have two Manson supplies (15V 60A switchmode & Triple output Linear) and they are bombproof and up to claimed spec and better.Don't worry about internal build quality they are not Chinese meltdown material, they meet Australian electrical safety rules and others too

author: Old Printer
author_rank: Frequent Contributor
timestamp: March 30, 2018, 02:21:14 am
content: This is not about about a current product, but I heard here on the forum a few months ago that the BK 1651 was the same as the Tektronix CPS250. They are made by the same mfg, really identical except for coloring. While not up to the standard of a Tek built product, certainly a reasonable unit, and available much cheaper with the BK badge. Tek took the time to produce a service manual up to their usual standards and I am using it to work on my BK unit. Not intending to derail the OP's thread, just an illustration of how the same unit can command wildly different prices under a different name.
APPA 106N RS232 Power - Page 1
Forum section: electronics / testgear

author: imk
author_rank: Regular Contributor
timestamp: March 29, 2018, 08:25:42 pm
content: Hello,So after much research I think i have narrowed my MM search to the APPA 106N AKA RS Pro IDM 106NQuestion is how is the RS232 PC interface powered, as i guess the optocoupler is to isolate the PC from the MM.Hence there is no electrical connection from the MM to the PC's RS232 Rx data line and this to my mind would require a pullup.I ask as if this is from RTS or DSR then what happens if you use a USB dongle, anyone tested it?Many thanks imk
R&S FSH3/6/18 Service Software - Page 1
Forum section: electronics / testgear

author: scopeman
author_rank: Frequent Contributor
timestamp: April 06, 2018, 03:05:32 am
content: Anyone have an idea where I can find the adjustment software referred to in the service manual for the Rhode & Schwarz FSH3/6/18.From the service manual page 35:"Adjustments can be performed only by using the adjustment program that is available from the R&SService Board on the R&S Internet site. Using this program prevents mistakes in the calibration data."SamW3OHM
RD JDS6600 Signal Generator - jitter on pulse output when duty cycle is not 50% - Page 1
Forum section: electronics / testgear

author: ArcticGeek
author_rank: Regular Contributor
timestamp: March 29, 2018, 03:30:55 pm
content: I recently purchased the RD JDS6600 40MHz signal generator from a US vendor on ebay, and received it last week. For the most part I was pleased with the unit, until I discovered this anomaly. When you generate a pulse output with a duty cycle other than 50%, you end up with 5ns of jitter on the pulse.I am including some scope shots that show this behavior. I have the generator configured to generate a 1VPP pulse, it is connected to my scope (with 50termination enabled) using a RG-58 cable.The first image is a 10MHz pulse with 50% duty cycle, this looks fine. The second image is the same frequency but a 40% duty cycle, you can see the 5ns jitter. The next 2 images are taken at 20% duty cycle at 10MHz.I then tried a few other frequencies, I've included a picture of a 1MHz 40% duty cycle and 500KHz at 60% duty cycle....the 5ns jitter remains. It really doesn't matter what frequency, anything with a duty cycle other than 50% has this problem. To make sure I wasn't having some sort of triggering problem with my scope, I dug out my boat anchor HP 8116A function generator, and a 10MHz 40% pulse looks as it should (show in the last picture). So this is odd behavior unique to the JDS6600 unit.I am assuming that the 5ns jitter comes from the 200MHz sample rate that the unit has. I don't really know how DDS signal generators work, but I am assuming this 5ns is an artifact of the 200MHz base clock. Is my assumption correct?To investigate a bit futher a took a look at a 10MHz 40% duty cycle pulse on a HP33120A generator, and it looks fine with no jitter.So what's up with this? Has anyone else observed this? Does a Feeltech FY6600 have this same issue? If not I might send this thing back.

author: pantelei4
author_rank: Regular Contributor
timestamp: March 29, 2018, 07:10:37 pm
content: https://www.eevblog.com/forum/testgear/anybody-know-anything-about-this-signal-generator/msg1263810/#msg1263810

author: ArcticGeek
author_rank: Regular Contributor
timestamp: March 29, 2018, 07:42:47 pm
content: @pantelei4:Thanks for the link. I actually did a search before I posted and ran across that thread, but I never saw the discussion about the jitter - I skimmed right over it. Thanks!Does anyone know if the FY6600 Feeltech has this same issue? I really don't like it for a lot of the stuff I am doing.
Fluke 115 lcd display question - Page 1
Forum section: electronics / testgear

author: cv007
author_rank: Frequent Contributor
timestamp: November 24, 2017, 01:27:36 am
content: I have a Fluke 115 which works fine, but the lcd viewing angle/contrast is not very good (seems like a somewhat common complaint with these). Usually I turn on the backlight to help out a little.Disassembled the meter to check it out. After reading the msp430 datasheet and app notes about driving an lcd display, I measured the external voltage divider resistors that are used for the lcd drive voltages (4 voltage levels total, ground is internal it seems). They are 100k resistors along with some unknown value of caps (they are 1uf or less from the looks of them). The measured values are 99k, 94k, 95k (from memory). I also measured the voltages and the values would swing in about a 10mv range.My question is- at what point do those 'unsymmetrical' voltages start affecting the display contrast? The msp430 app notes seem to indicate that its quite important that those drive voltages are symmetrical and stable, but they don't give any numbers to shoot for. They also show for best contrast (on 'larger' displays/segments- what qualifies as large I'm not sure) to use a low current op-amp in buffer mode for the drive voltages, with high value resistor divider as input.I'm not sure I want to start more testing unless I'm sure an improvement is possible. Maybe someone with experience driving lcd's can say whether its a waste of time or not. (The Fluke may start squealing if the soldering iron gets close to it- so don't want to upset it unnecessarily)Thanks.(I was also hoping to see active serial output on the unpopulated header connector tied to the msp430 serial port- but there is none)

author: M0UKD
author_rank: Contributor
timestamp: March 28, 2018, 08:17:59 pm
content: I have the same problem with my Fluke 115. I like the meter, but the LCD is not great. Could really do with a contrast adjust in certain lighting conditions and angles. My Fluke 179 is a lot better.I'd be interested if there is a mod that can be done to increase the LCD contrast.Here is an example comparing my new 115 to my old 233Cheers, John.
Save the Vintage Tek Microfiche Library - Page 1
Forum section: electronics / testgear

author: PrecisionAnalytic
author_rank: Regular Contributor
timestamp: March 28, 2018, 06:20:47 pm
content: See the link and donate. The microfiche library will be an awesome resource in digital format.https://www.youcaring.com/vintagetekmuseum-1085244
Wavetek 4808 intermittent problem - Page 1
Forum section: electronics / testgear

author: Kenny Powers
author_rank: Contributor
timestamp: March 28, 2018, 03:25:00 pm
content: Hello,I have a 4808 which is exhibiting intermittent misbehavior details below, has anyone else come across this and found a cure? I opened the unit and its spotless inside.For example, when set for 10VDC, it outputs 10V - but then the voltage (sometimes) slowly drift upwardsto, say, 12.6V.When this happens:-- the 1V and 100V ranges are seen to behave similarly- there is no output on the lower ranges- the 1000V range seems OK.The problem can be resolved, at least temporarily, by cycling the power or going up and down through the ranges a couple of times.(All other functions – ACV, Ohms etc. seem ok)
Rigol DSA815 - problem with tracking generator? - Page 1
Forum section: electronics / testgear

author: cyberfuzzy
author_rank: Contributor
timestamp: March 26, 2018, 10:36:58 pm
content: Hi. I'm not sure if there is a problem with the tracking generator of my Rigol DSA815. When I watch the signal with the scope it looks like the graph is not sinusoidal for <1 MHz.I recorded a sweep from 500 kHz to 1.5 MHz, sweep time is 10 seconds:On the spectrum analyzer the graph shows -18.1 dBm at 500 kHz and -19.2 dBm at 1.5 MHz. I don't think that the cable (RG-58) is that bad:The setup is a cable from the tracking generator to the scope and back to the input of the spectrum analyzer:Can anybody reproduce that issue? Is there a problem with my tracking generator or does every DSA815 act like this?

author: cyberfuzzy
author_rank: Contributor
timestamp: March 28, 2018, 10:36:49 am
content: According to this thread it seems to be normal for those cheap spectrum analyzers:https://www.eevblog.com/forum/testgear/rigol-dsa-815-tracking-generator-distortion/On my DSA815 the signal does not look sinusoidal for frequencies below 1 MHz. I took 3 screenshots with the scope for 10 kHz, 100 kHz and 1 MHz at zero span.
O Scope .OSC File Format? - Page 1
Forum section: electronics / testgear

author: MrAl
author_rank: Super Contributor
timestamp: March 29, 2018, 06:23:39 pm
content: Hello,Anyone have any info on the .OSC file format?This is a format output by a oscilloscope i picked up recently and i'd like to convert the file myself to text format.Thanks for any info or links.Note this is a file with voltage readings in it stored in digital format like 0xA8 for one reading.
LCR T4 bug! - Page 1
Forum section: electronics / testgear

author: clankill3r
author_rank: Newbie
timestamp: March 27, 2018, 04:58:22 pm
content: I have a LCR T4 tester and today I found a bug and I was wondering if other people have this.When I place a TIP122 transistor it will say it is a PNP / NPN depending on the way I put it in.Do more people have this?

author: madires
author_rank: Super Contributor
timestamp: March 27, 2018, 05:17:42 pm
content: The T4's firmware is a modified version of an older k-firmware. The current firmwares (k & m) detect base-emitter resistors and also freewheeling diodes on the same substrate as the transistor. Please seehttps://github.com/svn2github/transistortesterfor current firmwares and documentation.
Measuring standby power of  offline LED lamp - Page 1
Forum section: electronics / testgear

author: ocset
author_rank: Super Contributor
timestamp: March 27, 2018, 11:34:12 am
content: Hello,The attached is the Mains input current to our product (a 40W LED lamp) when in shutdown.Those spikes happen near the zero cross of the mains voltage.Its the voltage across a 30R sense resistor in the neutral line.It was supplied with 240VAC mains.We need to find the average active power of this.Do you know an instrument that can do this?We have Hameg 8115-2 power meter but its datasheet does not allure as to whether it can accurately measure such currents with such high crest factor, low level, and low power factor.Unfortunately we don’t have a sampling storage scope to be able to measure power via the means of summing up a period’s worth of sampled v.i. products and then dividing by the number of readings taken.Hameg 8115-2 Datasheet:http://www.farnell.com/datasheets/493586.pdf

author: jolshefsky
author_rank: Regular Contributor
timestamp: March 27, 2018, 12:17:04 pm
content: I'm pretty sure you can "be" the RMS meter. First ensure your sampling frequency is high enough to grab all the spikes accurately (Nyquist's rules). Then, assuming the waveform is reliably periodic (one cycle is basically identical to any other), get sample the voltages at each point. Put it in a spreadsheet and square the voltage at each point, take the mean (the mean-square), then the square root (root mean-square).

author: daveshah
author_rank: Unknown
timestamp: March 27, 2018, 02:24:48 pm
content: If you want power (as opposed to apparent power), the RMS is not the correct approach. In the spreadsheet you should have both voltage and current columns, multiply at each point to obtain instantaneous power, then average that to obtain average active power.

author: Ice-Tea
author_rank: Super Contributor
timestamp: March 27, 2018, 03:14:38 pm
content: The answer seems to be: a more expensive power meter?Yokogawa has some nice gear:https://tmi.yokogawa.com/solutions/products/digital-power-analyzers/digital-power-analyzers/

author: Fungus
author_rank: Super Contributor
timestamp: March 27, 2018, 04:30:46 pm
content: Quote from: treez on March 27, 2018, 11:34:12 amAdd a capacitor across the sense resistor. This will filter the spikes into a much smoother, easier to measure signal.(or add an inductor in series with the resistor - same thing)
Which AC/DC power clamp meter to go for? - Page 1
Forum section: electronics / testgear

author: drummerdimitri
author_rank: Frequent Contributor
timestamp: March 27, 2018, 07:13:11 am
content: It's not common to find these meters from name brands and they are hard to find.I want one that measures AC and DC power.AC power in KW/W, VA/KVA and energy KWh.PC communication with data logging is a plus.Price must be around 500$ or so.

author: drummerdimitri
author_rank: Frequent Contributor
timestamp: March 27, 2018, 07:32:20 am
content: Quote from: blueskull on March 27, 2018, 07:20:42 amThanks for the suggestion but I want a clamp meter since I want to make quick measurements and high current low voltage power measurements which I cannot do on this meter.Also I want an all in one solution unlike your DIY approach.
Sencore PS43 Porta-Pak - Any Info? - Page 1
Forum section: electronics / testgear

author: Twenty4Pack
author_rank: Contributor
timestamp: February 06, 2018, 10:34:16 pm
content: Hello all,Asking for help in getting a schematic and a component parts list for a Sencore PS43 Porta-Pak (battery eliminator). I'll appreciate any information you can send, even a photo of the interior and the transistor's part number would be helpful.I picked up a burned out Sencore PS43 the other day that doesn't work on batteries or on wall power. I took it apart and found an overheated point-to-point pc board and sticky remnants of something that didn't come from a resistor, diode, or transistor. All of the discreet components, one NPN and a bunch of diodes and resistors, were in good shape, so I'm guessing someone before me did their best with a 900W soldering gun. (Maybe replacing burnt components with whatever they had on hand?) The transformerappearsto be in good condition. I get different voltage readings from the secondary side that goes to the PC board, for what that's worth...Anyway, I've spent a long time searching and have decided I'm looking in the wrong places so need your help please. It's odd that all I'm finding are a few photos showing the front panel. It would be very surprising if the PS43 turned out to be a rare piece of equipment.Please let me know if I should have posted this request elsewhere so I can delete this and put it where it belongs.Don

author: Audioauthority7
author_rank: Newbie
timestamp: March 24, 2018, 11:55:23 pm
content: The transistor on the pc board is a common 2N3904.Barry

author: Twenty4Pack
author_rank: Contributor
timestamp: March 26, 2018, 08:46:43 pm
content: Hi,That's great news, thank you. Really doubt there's a problem with them, but while you're here, do you have a the part number for the diodes?Sitting here rhetorically wondering why the PS43 schematic is so difficult to find...Thanks again,Don (aka Bud)
Tek CSA7404 Bad PSU - Page 1
Forum section: electronics / testgear

author: macona
author_rank: Regular Contributor
timestamp: March 26, 2018, 07:00:59 pm
content: Got a Tek CSA7404 I am trying to bring back to life. Sits there tick-tick-ticking away, something is shorted on the HV side of the PSU. Looking at it with a thermal camera you can see the big power resistor that feeds the bulk capacitance glow brighter with each click.it is getting 5vsb so some of it is working. Tried replacing the main caps but no difference.Any schematics anywhere for the power supply? I think the next step is to see which sections of the PSU are actually dead and trace back.Or if anyone knows where I can find another power supply. Same power supply is used in TDS 6000, 7000, and TLA 600 series machines.Thanks
Siglent SAA30xx frequency calibration - Page 1
Forum section: electronics / testgear

author: rfspezi
author_rank: Regular Contributor
timestamp: March 25, 2018, 12:03:07 am
content: Does anybody know if it is somehow possible to calibrate/adjust the reference frequency inside the SAA30xx spectrum analyzer?

author: rf-loop
author_rank: Super Contributor
timestamp: March 25, 2018, 11:02:10 am
content: Afaik yes. Least I have adjusted it changing value: cali_freq_dacThis file include 6 bytes as: 0xdddd (dddd is for dac, originally in my individual unit dddd was ad2f and now it is aca8)It can find in firmdata0/calib directory (and this directory have lot of cal data. Do not corrupt this directory. It is best that before any touching inside it using telnet and example PuTTY, first make back up copy from whole calib directory to USB and keep it save. If this data is corrupted, loosed, only factory can reproduce factory calibration data - without full cal data, it is like electronic recycle material).This is fine adjust so do not change if you really are not sure you have enough good reference for check it.Without enough good freq counter it can do also using example good accurate checked 10MHz Rb or good well set GPS DO using scope and clock for compare freqs and calculate difference. (I use HP 53131A with known good ref and 5s gate time)In my SSA setting resolution is around 2.5mHz @ 10MHz Change value down and reference clock freq drops.Note, all time you change value then need reboot. So best method is first measure exactly your ref error.First measure exactly your reference freg after SSA is warmed 1 - 2 hour for perfect temperature equilibrium.Then do enough big adjust, example + or minus 3E8 (very roughly perhaps 2.5 Hz @10MHz depending your individual SSA) and then you know how much it change freq. After then calculate how much you need adjust for null your freq error.Good rule: Do not repair if not failed, do not adjust if there is not sure known real reason for need of adjustment and knowledge what exatly adjust and what all side effects or cross effect interactions it may do.Disclaimer: I do not know what all kind of interactions it may have in system. I have no any idea how it works and how it affect and how it also may produce some bad effect, hidden or visible. So if some follow this, he is fully and alone responsible himself what ever happend.
Agilent 34405A Error 635 - Page 1
Forum section: electronics / testgear

author: daveyk
author_rank: Frequent Contributor
timestamp: March 28, 2018, 09:49:11 pm
content: I had traded a burned up Agilent 33250A with someone on here for this 34405A 5 Digit DVM. It had worked great. After Trescal calibrated it, it started intermittently getting that Error 635 during bootup. Now it does it all the time.I rely on this DVM for the USB Data with my service software.I see a lot of fixes of re-flashing the pic chip. That is well beyond me. Is there any other fix or do I just have to buy a new DVM? I guess I would go for a 34401A if I can find one reasonable. My preference is to get this one working.Agilent states to update the firmware. I can't do that without being able to connect with it. I also read of a number of them bricking when updating the firmware,If someone know hows to fix this and wouldn't charge me an arm and a leg, I would ship this off to you and pay you for it.Thanks kindly for your help.Dave
TTi ts3022s bench supply current problem - Page 1
Forum section: electronics / testgear

author: fran
author_rank: Contributor
timestamp: March 21, 2018, 09:49:44 pm
content: Hi all,I'm looking for some help with a thandar ts3022s dual 30V 2A bench supply. It seems a fairly standard supply, both channels exhibit the same behaviour - power on, you can set voltage and current, but there is no current drive - when you add a load, the voltage collapses.Investigation so far:1. Close visual inspection under 3x mag to see any visual defects - none found2. Clean all pots - all measuring smoothly3. Measure all resistors, diodes on the control and PSU boards - all measure OK - but note this was done in circuit.4. Did a diode test on the 2n3055s (darlington arrangement) - all showed ok5. Replaced opamps anyway (TL072)6. Pulled all the transistors - all tested Ok7. Sense resistor is 0R1 - which is a challenge for any DMM to measure. I replaced it temporarily with a new (lower watt) one just to test, but no dice.Basically I'm stumped. I was hoping there was a dead short on the output, but the diode tests good and no short at the terminals. I can only think that the 2n3055s aren't being driven (and they don't get warm) - and hence the voltage drops as the driver has very little current capability. I've attached the schematic here. The only odd thing I can see is that R26 (just under the 3055s in the schematic) gets quite hot - and is 1k rather than 2.2k. But its not burnt etc.Any pointers you guys might have would be really appreciated. FYI, there is another thread here (https://www.eevblog.com/forum/beginners/drifting-bench-power-supply-and-low-impedance-on-dmm-mv-range/) where the guy had drift, but thats not the same as my problem.I've attached the schematic hereFran

author: Performa01
author_rank: Super Contributor
timestamp: March 22, 2018, 12:36:11 pm
content: You say it's the same problem on both channels, so there aren't that many options left.Make sure the Isolated/Tracking switch is set to Isolated. Still the same problem on both channels?If yes, then load one output (you say the voltage collapses) - does the 2nd output collapse as well (even though it's not loaded)?If yes, then observe the voltages over C2 and C3 (maybe also C1) and see how much they drop when the output is loaded.Best of luck!

author: fran
author_rank: Contributor
timestamp: March 22, 2018, 10:03:41 pm
content: Right, so I actually got this sorted out..... But through brute force and ignorance rather than knowledge and elegance. I reflowed all solder joints on the board, replaced all transistors bar the 3055s and it worked. I truthfully can't say which it was, or if it was both. I can say I could see no evidence of cold solder joints under low magnification. As a result I suspect it may well have been interplay between several components.The main thing now is she's back up and running hopefully for years to come.Another thing crossed off the fixit list.Thanks for the comments...Fran
Looking for an isotropic RF strength meter with PC interface - Page 1
Forum section: electronics / testgear

author: 0xfede
author_rank: Regular Contributor
timestamp: March 22, 2018, 02:54:58 pm
content: Hello all,I'm looking around for an isotropic RF strength meter with PC interface. The main use is as a feedback for RF generator to check CISPR11 immunity precompliance. The radiated level should be 10V/m and 20V/m (+-10% IIRC) from 70MHZ to 2.7GHZ.There are a lot of low cost devices around but none offers a PC interface and their accuracy is a big question.There are a few active antennas (that I can connect to a SA) but I don't have any experience.Then the classic Chavin Arnoux CA43 could be a solution but it is rather expensive (3k€ + VAT).I don't need a class A instrument, just something to be in the right ballpark.Any advice?Thanks,0xfede
Analog VOM - Page 1
Forum section: electronics / testgear

author: dseyst
author_rank: Contributor
timestamp: March 22, 2018, 12:52:09 pm
content: I am going to buy a used Triplett 630 or Simpson 260 and was wondering which is considered better and/or more accurate. I have a number of other less expensive analog multimeters that are accurate on some scales but not on others and would appreciate any opinions.

author: BravoV
author_rank: Super Contributor
timestamp: March 22, 2018, 01:18:00 pm
content: Made a similar discussion while ago here ->Classic analog moving coil multimeter, which are considered best ones ?And it looks like Simpson 260 got most of the votes.

author: Stray Electron
author_rank: Super Contributor
timestamp: March 22, 2018, 01:32:24 pm
content: I've owned several of both and my vote would be for the Simpson. But FYI on both brands it's not uncommon for the precision WW resistors to be damaged by misuse and for some ranges to be out of tolerance or non-functional on used meters, so buyer beware. I still have one 630 and three 260s.
Lecroy model descriptions - Page 1
Forum section: electronics / testgear

author: alexjaw69
author_rank: Newbie
timestamp: March 22, 2018, 05:08:44 am
content: I'm looking for a Lecroy 9354 on ebay and found that there are a number of different models A, AM, L, CM, etc...I though this was simple but having searched around for a while I still don't know what the letters describe.

author: alexjaw69
author_rank: Newbie
timestamp: March 22, 2018, 06:57:38 am
content: Thanks to Tony,see his answer onhttps://electronics.stackexchange.com/a/363963/183121

author: Stray Electron
author_rank: Super Contributor
timestamp: March 22, 2018, 09:54:17 am
content: The chart that they show at the link is directly out of the specification section in LeCroy's manual for the scope. I think it's also in the brochure for the scope. The problem with LeCroy is that those letter suffices don't always mean the same thing form one series to another so you have to find the specifications for your model's specific series. The good news is that in the real world those letter suffices (and the corresponding memory size and speed) make little difference unless you're really pushing the acquisition speed limits of that series. The LeCroy scopes have some outstanding hardware and software options but you have to power them up and use the software menus to see what is enabled in each individual scope since there's no way to tell from just the model number.I have four 9354s and IMO they're GREAT scopes, but they are a bit long in the tooth. But they DO seem to last far longer than the Tektronix scopes as far as capacitor failures are concerned and their math capabilities runs circles around the HP or Tektronix scopes! And the other GOOD news is that LeCroy has released the code to enable the software options so it's very easy to turn on all of the options. Also the main memory (not the acquisition memory) uses standard (a while back now!) SIMMs so you can add more main memory very cheaply and easily.
Siglent SDS2000X and sigrok? - Page 1
Forum section: electronics / testgear

author: PolarCrew
author_rank: Newbie
timestamp: March 21, 2018, 11:20:44 am
content: Hello,Is there SDS200X owners that have used sigrok?My question is: Does it support digital channel acquition of logic channels over USB ?Maybe it's my bad english but i don't know if they say on sigrok wiki that there isold version of SDS2000X that doesn't support digitalchannels capture from sigrok. Or do they mean thatSDS2000X is old serie that doesn't support digitalchannel capture.This quote is from sigrok wiki:"Theolder series SDS2000X Logic Analyzerfunction does not support acquisition of the LA channels over VXI or USB. Due to flash memory program limitations the code for this function does not fit. Its not clear if newer "E" scopes will come functionality for the SDS2000 series scopes."https://sigrok.org/wiki/Siglent_SDS2000X_seriesAnd yes, I'm about to purchase SDS2000X model scope

author: abraxa
author_rank: Frequent Contributor
timestamp: March 21, 2018, 11:46:39 am
content: If you have a github account, I suggest you open an "issue" with marchelh's libsigrok fork:https://github.com/marchelh/libsigrok/issuesHe's the one who added support for the scope series and also wrote the wiki page that you're refering to. I agree by the way, the wording could be clearer.

author: PolarCrew
author_rank: Newbie
timestamp: March 21, 2018, 12:24:12 pm
content: Quote from: abraxa on March 21, 2018, 11:46:39 amThank you!

author: tautech
author_rank: Super Contributor
timestamp: March 21, 2018, 05:36:07 pm
content: WRT Sigrok.From a contact in Siglent:- Our current scopes only return Analog Channel data- The 1X, 2, and 2X all work with Sigrok (but only Analog)- Soon, we hope the 4 channel XEs will be able to return digital data, tooQuoteCorrect, they don't.
EE101 debugger you build yourself - Page 1
Forum section: electronics / testgear

author: firmwareguy
author_rank: Newbie
timestamp: March 20, 2018, 08:25:32 pm
content: I use their EE101 Insight-Pro and it's really a great tool. Just saw they released a DIY for $29 plus about $13 in parts. Just throwing it out there since it's saved me boatloads of time.www.ee101.com

author: hugo
author_rank: Regular Contributor
timestamp: March 21, 2018, 12:37:19 am
content: Why don't post the link?EE101 Insight-Pro™ $369

author: firmwareguy
author_rank: Newbie
timestamp: March 21, 2018, 01:37:51 am
content: Yes but the EE101 Insight-Maker version is $29 plus a few more bucks for hardware. The link to it ishttps://www.ee101.com/maker.html
Hantek Power Supply PPS2116A review - Page 1
Forum section: electronics / testgear

author: jtronix
author_rank: Regular Contributor
timestamp: August 21, 2013, 04:56:04 pm
content: this power supply looks good, can any body tell review of this PS?please share video and experience with this PS

author: Bored@Work
author_rank: Super Contributor
timestamp: August 21, 2013, 07:15:21 pm
content: Rebranded. Also known as Protek P6035, Vantek DPS 3305P or Quakko HY3005DP. The original manufacturer is unknown. Maybe Mastech or Hyelec. There is also a 3A version around.These power supplies are, depending on firmware and the phase of the moon, crappy or really crappy (as in kills connected circuits).

author: dssence
author_rank: Regular Contributor
timestamp: February 11, 2014, 02:56:56 am
content: Quote from: Bored@Work on August 21, 2013, 07:15:21 pmhey I've been throughout all available supplies over at ebay, amazon , going from chinese manufactuers mastech, korad etc etc. Until I finally came up with hantek which seems a respectable manufacturer, and was thinking going with this supply. But there aren't any reviews over on youtube or whatsoever. Should I go with this? instead of mastech ?

author: GiskardReventlov
author_rank: Frequent Contributor
timestamp: February 11, 2014, 04:56:06 am
content: I have no direct experience with this device. But looks aren't everything.

author: marcone
author_rank: Contributor
timestamp: March 19, 2018, 05:17:10 pm
content: Seems to me like the sucessor to the Korad reviewed - and broken - by Dave some years back.Would not buy it just yet in the absemce of some positive reviews/teardowns, the Korad took some time to be sorted out.
Overloading scope Y amp during averaging? - Page 1
Forum section: electronics / testgear

author: Circlotron
author_rank: Super Contributor
timestamp: March 19, 2018, 04:15:43 am
content: Say I look at a very small repetitive waveform with lots of uncorrelated noise. Switch to averaging mode and the noise goes way down and I can make out the signal. If I wind up the Y sensitivity so that the signal is a reasonable size, does this mean that the noise which would now be off the top and bottom of the screen would be overloading the Y amplifier and perhaps affecting the results, or is this taken care of by the averaging?

author: 0xfede
author_rank: Regular Contributor
timestamp: March 19, 2018, 07:25:19 am
content: Hi Circlotron,on a DSO the averaging is made in the digital domain and therefore after the ADC. This means that if you saturate the converter and/or the input amplifier you will end with a distorted signal. This is valid only when in real time but on modern DSO you can acquire your signal with an higher Volt/Div setting, Stop the acquisition and then vertically zoom the waveform (in this case the zoom in is performed in the digital domain where usually there is much more headroom).Best,0xfede

author: Circlotron
author_rank: Super Contributor
timestamp: March 19, 2018, 08:03:06 am
content: I expect that would work, but you would probably not have much vertical resolution. Might be good enough though.

author: 0xfede
author_rank: Regular Contributor
timestamp: March 19, 2018, 08:24:28 am
content: If this is not enough for your measurement you may also want to add a low pass filter between the DUT and the DSO.Best,0xfede
PicoScope timebase oscillator calibration - Page 1
Forum section: electronics / testgear

author: Scratch.HTF
author_rank: Regular Contributor
timestamp: March 16, 2018, 09:31:38 am
content: I am looking at the PicoScope 3000 or 5000 which is within my price range, but unfortunately these series do not have an option for an external frequency reference and because of that, I am wondering if the timebase oscillator can be calibrated.

author: Performa01
author_rank: Super Contributor
timestamp: March 16, 2018, 11:17:06 am
content: I have 3000 and 4000 series PicoScopes and I don't know any official way to calibrate their timebase.On the other hand, the higher bandwidth models (100MHz and up) of the 3000 series have an initial accuracy of +/-2ppm, that's not too bad as a starting point.

author: Safar
author_rank: Regular Contributor
timestamp: March 18, 2018, 05:37:22 pm
content: I have 5000 200MHz 3 years old model but also do not know way for adjust clock but for me clock is accuracy enough. I feed 10 and 20 MHz from GPSDO to Pico and get 0.2561 Hz sigma on 10MHz (on 200000 samples) and 0.6274Hz on 20MHz. It is looks like ~0.03ppm on sigma! But sigma not all errors and I can see in "average" only 4 digs. FFT freq accuracy also looks good (about 1..2 bins)
Best in Desoldering Stations -  JBC DDSE-2B REWORK STATION - Page 1
Forum section: electronics / testgear

author: Harb
author_rank: Regular Contributor
timestamp: March 15, 2018, 03:40:10 am
content: Not sure if this is the right place, but here goes.....a Question that has been asked before, but I am after Current Info.If money was not an object, what would you consider to be the out and out best Desoldering Station available today ?Its time to upgrade, and I cover all forms of construction, so availability of Acc's are important also.

author: xmo
author_rank: Regular Contributor
timestamp: March 15, 2018, 04:33:47 am
content: Pace

author: Harb
author_rank: Regular Contributor
timestamp: March 15, 2018, 08:51:19 am
content: Yeah I have a bit of older Pace gear....its ok.I have been looking at the HAKKO FR-410 but I am undecided still........I was wondering if there is a better choice and why.......and then there is which handpiece, the pistol grip or straight one....and again why.

author: helius
author_rank: Super Contributor
timestamp: March 15, 2018, 09:06:54 am
content: Hakko seem to have recently matched the key Pace advantages: a clog-prevention system, and tips specifically for cleaning SMD pads.

author: Harb
author_rank: Regular Contributor
timestamp: March 15, 2018, 09:23:45 am
content: I must have a look at the new Pace......mine are years old, and maybe they are still the way to go...

author: Harb
author_rank: Regular Contributor
timestamp: March 18, 2018, 10:04:45 am
content: JBC DDSE-2B REWORK STATIONanyone have an opinion on these......are they a good thingI am going back and forth between the FR-410 Hakko which is a stand alone Desoldering station, or going with a Soldering / Desoldering station, the JBC DDSE-2B REWORK STATION which I can get at a good price.
Kikusui PWR / PWR-01 series - Page 1
Forum section: electronics / testgear

author: theatrus
author_rank: Frequent Contributor
timestamp: March 04, 2018, 10:06:12 pm
content: I very rarely run into anything by Kikusui, but these switch-mode bench-top supplies caught my eye:http://www.kikusui.co.jp/en/product/detail.php?IdFamily=0143Very wide ranges - for example, the 400W (smallest) model has a 0-40V/0-40A (!) variant, as well as a 0-650V(!)/0-1.85A variant. They even seem to list them on Amazon for direct sale, and the pricing isn't terrible (just under 1k) for the feature set. LXI, USB, simple front panel, and even some analog control functionality.Anyone have any experience with these supplies or anything else in the family?

author: lundmar
author_rank: Frequent Contributor
timestamp: March 17, 2018, 08:06:48 pm
content: Kikusui kindly sponsored the open source lxi-tools project one of their new PMX series benchtop power supplies, the PMX35-5A to be specific.I'm impressed by the performance and quality of the power supply. Assuming that the PWR series is of the same quality I would think it to be a good buy.Seehttps://www.eevblog.com/forum/testgear/open-source-lxi-tools-and-liblxi-v1-0-released-for-gnulinux/msg1418784/#msg1418784

author: theatrus
author_rank: Frequent Contributor
timestamp: March 17, 2018, 09:29:19 pm
content: Fantastic. Love it when companies sponsor or contribute back to open source.
Lost zero-ing tool for TA041 active probe - Page 1
Forum section: electronics / testgear

author: ocset
author_rank: Super Contributor
timestamp: March 17, 2018, 09:55:59 am
content: Hello,We have lost the little screwdriver which is needed to zero our TA041 active probe.None of our standard screwdrivers seem to work with it. I shone a torch down the screw hole but cant even see what type of head the screw is.Do you know a part number for the screwdriver which adjusts the zero-ing?TA041 active probe.https://www.picotech.com/accessories/high-voltage-active-differential-probes/25-mhz-700-v-differential-probe
Fluke Meter Accuracy Explanation Needed - Page 1
Forum section: electronics / testgear

author: K1JOS
author_rank: Regular Contributor
timestamp: March 16, 2018, 02:25:17 pm
content: I got a Fluke 365 clamp meter as a gift. I am a bit confused looking at the datasheet, the lowest resolution is 0.1 A and accuracy is 2% +/- 5 digits. The maximal number of displayed digits is 4. So what is the range of actual values if I am reading 0.1 A? Does this mean it is in the range of 0.098 (+/- 0.00001) to 0.1002 (+/- 0.00001)? If so, when would the "5 digits" ever be relevant beyond the 2% accuracy limits?Jerry

author: rsjsouza
author_rank: Super Contributor
timestamp: March 16, 2018, 02:48:20 pm
content: I think you will find good explanation and examples at:http://brianhoskins.uk/digital-multimeter-accuracy/

author: retrolefty
author_rank: Super Contributor
timestamp: March 16, 2018, 05:57:50 pm
content: QuoteI'm pretty sure the +/- 5 digit part really means +/- 5 counts of the least significant digit. Accuracy specifications can be quite confusing. Does the 2% part mean 2% of total range or 2% of meaured value?It best to turn this over to a true volt nut, of which this forum has several, that may educate us others. Or maybe it won't.

author: Performa01
author_rank: Super Contributor
timestamp: March 16, 2018, 07:03:25 pm
content: Accuracy spec. includes gain and offset error.Gain error is always in % relative to the measured value.Offset is an absolute error and can be specified either in % of the range or in digits.It is of course not really an option to "measure" at the edge of the resolution, but just for fun let's calculate the specified error for 0.1A in the 200.0A range:Gain error = +/-2% x 0.1A = +/-0.002A;Offset error = +/-5 counts/digits = +/-0.5A; (since there are +/-2000 counts, it could also be specified as +/-0.25% of the range)Total error = +/-0.5002A;As can be seen, the gain error becomes negligible here and any display from -000.5A to +000.5A would still be in spec.

author: dacman
author_rank: Frequent Contributor
timestamp: March 16, 2018, 09:23:26 pm
content: Fluke isn't the only manufacturer to use digits when they meant counts. If I were testing the meter for accuracy with a 0.1 A input, to be in-tolerance, it would need to display between -0.4 to 0.6. If the standards were adjusted for a 0.1 A display (on the Fluke meter), then the standards would need to be sourcing between -0.4 and 0.6.
Siglent SDG1025 Square wave question - Page 1
Forum section: electronics / testgear

author: tip29
author_rank: Newbie
timestamp: March 21, 2018, 11:34:08 pm
content: Hi all,I just bought Siglent SDG1025 function generator mainly to generate pwm signal for DC/DC converter (I am trying to learn DC/DC converters).I found its output @ 4Vpp square wave has 1V overshoot and ringing. I have attached a picture below. Is this acceptable?? Looks terrible to me.Also, the falling edge has 20ns jitter. I read about the jitter problem on some posts and the solution was to use pulse function. But the ringing on pulse function is even worse.I am just a hobbyist and this is my first function generator. I feel like I should have just gotten a used agilent.Thanks.

author: DaJMasta
author_rank: Super Contributor
timestamp: March 21, 2018, 11:39:10 pm
content: Are you using a normal scope probe? Have you tried connecting the BNC directly?This is common because of the extra inductance of the probe's ground lead making a loop in the circuit and doesn't necessarily mean that it's actually being generated - it could be entirely an artifact of the way you are probing the signal.

author: tip29
author_rank: Newbie
timestamp: March 21, 2018, 11:51:10 pm
content: I had BNC to minigrabber cable from the SDG connected to the probe of the oscilloscope. The ringing diminished while probing BNC of the SDG directly.I am stupid.Thanks!

author: tautech
author_rank: Super Contributor
timestamp: March 21, 2018, 11:53:25 pm
content: As DaJMasta says, your probing/measurement techniques are the reason for this.All Siglent AWG's are designed for 50impedance loads so to display the waveform accurately you must terminate into a 50 ohm load. Try a BNC cable and a BNC 50 ohm feed through.Another trap for young players is the Load setting in the Utility menu. Hi-Z or 50 ohm selection ONLY adjusts the output voltage to match the intended load and as mentioned above the output impedance is always 50 ohm.

author: DaJMasta
author_rank: Super Contributor
timestamp: March 21, 2018, 11:54:04 pm
content: Quote from: tip29 on March 21, 2018, 11:51:10 pmIt's been a while, but I've done it too. No worries
MA220 clamp meter stuck in overload on all current ranges - Page 1
Forum section: electronics / testgear

author: VoidsWarranties
author_rank: Contributor
timestamp: March 16, 2018, 01:02:59 pm
content: I was using the meter to check resistance then when I switch to current, all of them are reading OL.Could the clamp have become magnetized? How could this be fixed?Sent from my iPhone using Tapatalk
Used Tektronix 2235A - things to check for? - Page 1
Forum section: electronics / testgear

author: EncomLab
author_rank: Contributor
timestamp: March 13, 2018, 09:51:45 pm
content: Picked these up today from a University for nearly nothing - anything I should check for or be aware of with this model? I've used a 2 channel analog scope before but its been years.

author: David Hess
author_rank: Super Contributor
timestamp: March 15, 2018, 04:22:01 am
content: The 2235A was the final refinement of the 2 channel 22xx series so many of the problems with the earlier models were solved. The late production year also means these are less likely to have worn out aluminum electrolytic capacitors in the power supply. So if it works, then it works and I would not risk borrowing trouble by messing with it unnecessarily.Check the basic operation of all of the controls. Check the CRT performance for double peaking and blooming at high intensities.I do not remember if the 2235A has a fan or not but if it does, check that it is working and not noisy. The line side X and Y EMI filter capacitors are known to fail with age and should be replaced *if* you have to gain access to that area for other reasons. The previously mentioned aluminum electrolytic capacitors are nearing the end of their life.

author: tecman
author_rank: Frequent Contributor
timestamp: March 15, 2018, 06:38:03 pm
content: Nice catch. Curious what you paid for them ?paul
Tektronix 222 & 222PS scopes - Page 1
Forum section: electronics / testgear

author: sarel.wagner
author_rank: Regular Contributor
timestamp: March 06, 2018, 06:44:39 pm
content: Inbound are 1 Tektronix 222 and another 222PS Oscilloscopes. Depending on what I find, will build new battery packs ( a given) and do a teardown maybe if that is justified. Unlike Dave, these will be powered on firstWill update here as and when I get them. Kinda excited with these babies inbound.

author: sarel.wagner
author_rank: Regular Contributor
timestamp: March 09, 2018, 08:11:32 am
content: https://i.imgur.com/p042x8n.jpg]andhttps://i.imgur.com/Uq0wBu4.jpg]

author: sarel.wagner
author_rank: Regular Contributor
timestamp: March 14, 2018, 04:15:25 pm
content: So here they are. 2 x 1X probe and 2 x 10X probes, missing 3 of the earth leads. These are special, and because the channels are isolated, ya need emhttps://i.imgur.com/C94vi93.jpg]

author: tautech
author_rank: Super Contributor
timestamp: March 14, 2018, 11:56:46 pm
content: Cute little things, what vintage are they sarel ?

author: sarel.wagner
author_rank: Regular Contributor
timestamp: March 16, 2018, 12:13:29 pm
content: Hi, seems to be 93 and 94 according to the battery date codes. Have not opened them up, both are working fine.
Chinese test equipment: What is used inside - Page 1
Forum section: electronics / testgear

author: Scratch.HTF
author_rank: Regular Contributor
timestamp: March 15, 2018, 07:44:53 am
content: From what I can see, Hantek uses the following in current (at the time of posting) models of test equipment: Samsung SOCs, Micron DRAM, Xilinx programmable logic, Cypress high speed USB microcontrollers, Texas Instruments DC-DC converters, Analog Devices high speed ADCs/DACs and clock generators (some short memory AWGs may use Burr-Brown (TI) high speed DACs).So therefore, I am curious on what SOCs/DRAM/programmable logic/high speed USB microcontrollers/DC-DC converters/high speed clock generators and high speed ADCs/DACs are used by current model Chinese test equipment including from Siglent, Rigol, Owon, Uni-T, Atten, and Micsig.
Fluke 289 Will Not Power On - Page 1
Forum section: electronics / testgear

author: Hornethandler
author_rank: Contributor
timestamp: March 14, 2018, 01:02:35 pm
content: Occasionally my Fluke 289 will not power on. However, when you remove and reinstall the battery pack the meter starts working again. It’s happened twice in about 20 power on cycles. The batteries and all connections are good and it has the latest firmware (1.16) installed. Any ideas???Thanks,Mack

author: Simon
author_rank: Unknown
timestamp: March 15, 2018, 07:43:48 am
content: Hello, please do not start more than one identical topic, it is extremely frustrating for people trying to help you.