hybridfree/eevblog-posts huggingface dataset:
Rigol DHO800 DHO1000 phase measurement  - Page 1
Forum section: electronics / testgear

author: DavidE
author_rank: Newbie
timestamp: October 25, 2023, 04:08:47 pm
content: I an interested in buying a DHO800 or DHO1000. For my work, I use the phase measurement on square waves. Some oscilloscopes struggle with this and others like the TDS2024C do fine.Anyone have experience they can share about this measurement on the DHO800 or 1000 scopes?This can easily be checked by measuring the signal on both sides of an inverter to get 180 degrees.

author: Serg65536
author_rank: Regular Contributor
timestamp: October 25, 2023, 04:23:16 pm
content: The DHO800 series has multiple phase measurements types.From the page 130 of the user manual :5. Phase(r-r): indicates the phase deviation between the threshold middle values ofthe rising edge of Source A and that of Source B. The phase formula is as follows: <equation>Wherein, PhaseARBR represents Phase(r-r), DelayARBR represents Delay(r-r), andPeriodsourceA represents the period of Source A.Phase(f-f): indicates the phase deviation between the threshold middle values ofthe falling edge of Source A and that of Source B. The phase formula is as follows:PeriodsourceA represents the period of Source A.7. Phase(r-f): indicates the phase deviation between the threshold middle values ofthe rising edge of Source A and the falling edge of Source B. The phase formula isas follows: <equation>8. Phase(f-r): indicates the phase deviation between the threshold middle values ofthe falling edge of Source A and the rising edge of Source B. The phase formula isWherein, PhaseAFBR represents Phase (f-r), DelayAFBR represents Delay(f-r), andPeriodsourceA represents the period of Source A.Source A and Source B can be any channel among CH1-CH4 and Math1-Math4.• The default threshold middle value is 50%.

author: Fungus
author_rank: Super Contributor
timestamp: October 25, 2023, 04:53:41 pm
content: The DHO800 has plenty of measurements of this type. See manual for details.Here's mine measuring two square waves that are 45 degrees out of phase:
Any experience with Korad KA3005PS? - Page 1
Forum section: electronics / testgear

author: tom66
author_rank: Super Contributor
timestamp: June 15, 2023, 01:06:39 pm
content: We've bought Korad KA3005P before and use them around the office with no major complaints.Now looking to buy a few KA3005PS as it seems the older version is out of stock or possibly discontinued. It seems to be subtly different, has anyone used one? Is it built as well as KA3005P? (which may not be perfect, but we have not managed to blow any up!)

author: Algoma
author_rank: Frequent Contributor
timestamp: June 15, 2023, 02:19:40 pm
content: I think Korad is a fair choice for a basic unit given the cost. That newer KA3005PS model looks to have a bit more resolution and improved feedback on the display.Eleshop has a good comparison page for the difference.https://eleshop.eu/korad-ka3005ps.html

author: radiolistener
author_rank: Super Contributor
timestamp: June 15, 2023, 11:49:44 pm
content: I think you're needs to make sure that this KA3005PS is linear power supply.Usually new modifications of Chinese devices are worse than previous. This is because they are trying to reduce the price of a new model. I don't see any mention about "linear regulation" in the product description. So, it's possible that a new model can use switching mode regulator, this would be a serious disadvantage.

author: J-R
author_rank: Super Contributor
timestamp: June 16, 2023, 12:40:58 am
content: The weight is listed at 4.3kg which is similar to the previous model, so odds are good it's still linear.

author: Algoma
author_rank: Frequent Contributor
timestamp: October 19, 2023, 08:35:49 pm
content: Perhaps the reseller was the source of the compromised disk. A warehouse worker paid to slip disks into the "for export" models. How was the packaging, factory sealed in any way?

author: DaneLaw
author_rank: Frequent Contributor
timestamp: October 20, 2023, 04:17:06 am
content: Tons of false positives, amongst more crude executables.so you likely need to include some more details, as certain Defender / AV programs will from time to time trigger wrongly (false positive) and label it to a segment of virusesKorad is an official vendor making quite a few devices and they would be out in a heartbeat from all their Western resellers if their official CD were up to no good.https://www.koradtechnology.com/got two Korads a handfull of years back.. - in regards to linear programable PSUs, they are as cheap as it gets.KA3003P.KD3005P- needed linear-psu for lazing purpose, here A brief look at the inside of these older units, that cost between 60 to 80 US (delivered)https://tinyurl.com/mry3zfuj

author: coromonadalix
author_rank: Super Contributor
timestamp: October 25, 2023, 09:11:16 am
content: and maybe there was false positive ? some av are easily triggered ...... since some dont love foreign stuff ... even triggered with file names ...
Agilent 8714ET Opt 100 Velocity Factor problem? - Page 1
Forum section: electronics / testgear

author: wd5jfr
author_rank: Regular Contributor
timestamp: October 22, 2023, 11:57:16 pm
content: I wanted to check the velocity factor on some blue Gore mini-coax that looks like RG-174 but with braided shield and silver plated center conductor with teflon dielectric. I've confirmed it's 50 ohm by measuring the capacitance and inductance and calculating, result is 50 ohms. After several attempts I think I have the correct command sequence, hard keys are in all caps and soft are lower case.PRESETBEGINUser begin (turned OFF)CableFault locationCALCalibrate cableSpecify length (enter number of feet)Measure cableThe response I get is "loss or velocity out of range"I've tried this on known good 50 feet of RG213 and 100 feet of RG174 with same result. I think I have the correct command set and I wonder if anyone can confirm this and let me know it's me or the 8714ET.Thanks

author: KrudyZ
author_rank: Frequent Contributor
timestamp: October 24, 2023, 03:00:12 am
content: Works on my 8714ET, but I used a much shorter cable (4ft).It gave a reasonable velocity factor of 0.68.Make sure the cable is unterminated.

author: wd5jfr
author_rank: Regular Contributor
timestamp: October 24, 2023, 07:04:22 pm
content: The manual says use at least 30 feet.So I'll try something shorter and let you know what I get.Did you use the exact same steps I posted?Thanks

author: wd5jfr
author_rank: Regular Contributor
timestamp: October 24, 2023, 11:04:23 pm
content: I just tried a 6 ft BNC jumper and it came with a velocity of 0.74 which sounds reasonable. Then the RG213 tested OK, dirty connector. Currently I have no way to connectorize the RG174 or the Gore cable so I used a solder turret banana plug to BNC and now I suspect it's the impedance mismatch at the 8714 and the DUT that is upsetting the reading. So now I have to figure out what kind of connectors I'm going to use for the Rg174 and Gore cables: crimp vs solder, BNC vs SMA and minimize expense since I don't think I see me making more than 10 cables. HF to 2 meters & maybe 440 is the limit. I'm 82 and would appreciate recommendations economical connectorization for RG174.Thanks

author: KrudyZ
author_rank: Frequent Contributor
timestamp: October 25, 2023, 04:28:31 am
content: The shortest length it let me enter was 1m, so I'm assuming that you can measure cables shorter than 30ft.WRT connectors for RG174, you can get SMA, BNC and type N.Out of the three I would pick SMA, but what you should choose of course this depends on how you want to use the cable you make.I have N to SMA adapters on my HP8714ET and use SMA for pretty much everything >1GHz.
Siglent Instruments Protective cover - Page 1
Forum section: electronics / testgear

author: jpm1025
author_rank: Newbie
timestamp: October 24, 2023, 05:44:41 pm
content: Just a heads up. I don't know how many Siglent instruments have this but the Siglent SSA3021X Plus has two protective covers on the display screen. So before you send your instrument back for bubbles in the display, look for a second protective cover. It doesn't have the little red tab like the first cover does.
Fluke RF Probe - Page 1
Forum section: electronics / testgear

author: mojoe
author_rank: Frequent Contributor
timestamp: October 18, 2023, 09:09:46 am
content: Does anyone know the difference between the 85RF and the 85RF II? The specs look the same. Other than people selling them, a web search brings up nothing useful.

author: stevebyan
author_rank: Contributor
timestamp: October 24, 2023, 03:37:44 pm
content: Quote from: mojoe on October 18, 2023, 09:09:46 amNot quite the same. The 85RF II has poorer frequency response specs over 200 MHz and a higher input capacitance (9 pF versus 3 pF). The schematic differs; the 85RF II uses two BAT41 Schottky diodes in place of the single germanium diode used in the 85RF. Both also use a single 1N4148 to linearize the response.
Where can I find info on Firmware updates. Hantek - Page 1
Forum section: electronics / testgear

author: chinoy
author_rank: Regular Contributor
timestamp: October 24, 2023, 07:09:11 am
content: So Ive not updated the firmware on my Hantek DSO5000 scope.Before I just visit their web site grab the latest firmware and update.Id like to know what changes were made in each firmware.Does anybody have a history of firmware updates or notes on what changes or problems were addressed.Even if its just for the latest firmware. On their web site I could only find the latest version with no info.
Tektronix TDS 520D Channel hack - Page 1
Forum section: electronics / testgear

author: ts125rider
author_rank: Newbie
timestamp: October 24, 2023, 03:46:02 pm
content: Hi!I’ve got a Tektronix TDS 520D oscilloscope, which is kinda old digital oscilloscope and has kinda weird channel configuration.It has 2 regular channels and 2 “auxiliary” channels. It can display only 2 channels any given time.This scope looks very similar to TDS540D which has 4 regular channels and it can use all of them in the same time.Do you think that the TDS 520 can be hacked to think it is a TDS 540 and use all the channels?Does anyone have experience with that?Thanks,Mate

author: TERRA Operative
author_rank: Super Contributor
timestamp: October 25, 2023, 12:05:19 pm
content: The TDS520 and TDS540 scopes have different acquisition boards, so it is unfortunately not possible to have all four channels active simultaneously on a TDS520.
Question regarding what's "hackable" on a Siglent Oscilloscope - Page 1
Forum section: electronics / testgear

author: GCRoberts
author_rank: Newbie
timestamp: October 23, 2023, 10:44:27 pm
content: I'm looking at the Siglent SDS2204X Plus Oscilloscope. It has a number of license upgrades.SDS-2000XP-FG: 50 MHz USB Function/Arbitrary Waveform Generator (Software） ($229.00)SDS-2000XP-16LA: MSO function software for SDS2000X Plus oscilloscope, 16-channel, does not include hardware ($175.00)SDS-2000XP-Flexray: FlexRay serial triggering and decoding, software license ($275.00)SDS-2000XP-MIL1553B: MIL-STD-1553B serial triggering and decoding, software license ($275.00)SDS-2000XP-CAN-FD: CAN FD serial triggering and decoding, software license ($275.00)SDS-2000XP-I2S: I2S serial triggering and decoding, software license ($275.00)SDS-2000XP-SENT: SENT trigger and serial decoding activation license ($275.00)SDS-2000XP-MANCH: Manchester trigger and serial decoding software activation license ($275.00)SDS2000XP-4BW03: SDS2204X Plus 200 MHz 4 Channel Scope upgrade to 350 MHz ($1,199.00)I don't care about all of them, but I'd love to be able to enable the Waveform Generator, MSO function, and the 350MHz upgrade. Can all these options be enabled via a hack?Note: I am aware that the MSO function by itself is useless and I'd have to purchase SPL2016: Logic Probe, 16-channel ($379.00)

author: KungFuJosh
author_rank: Super Contributor
timestamp: October 23, 2023, 11:34:39 pm
content: https://www.eevblog.com/forum/testgear/siglent-sds2000x-plus-hack/

author: tautech
author_rank: Super Contributor
timestamp: October 23, 2023, 11:39:54 pm
content: Welcome to the forum.As luck would have it there's a promo running on these DSO's offering a great deal on an option bundle package at fantastic pricing but sadly not for the US.https://int.siglent.com/info/detail-74.html

author: coromonadalix
author_rank: Super Contributor
timestamp: October 24, 2023, 05:51:21 am
content: you dont care loll but once you understand how to add all of them loll you'll get interested
MSO5000 - Page 1
Forum section: electronics / testgear

author: Alexan
author_rank: Contributor
timestamp: October 24, 2023, 12:17:13 am
content: Hello! Became the proud owner of MSO5074. Can you tell me if the signal on the screen should be distorted when trying to view the uppermost part when the vertical range is outside the screen? Link to video.https://youtu.be/3o0KSxU2eVE?feature=shared

author: voltsandjolts
author_rank: Unknown
timestamp: October 24, 2023, 06:36:56 am
content: IGNORE THIS THREADUser reposted same question here:https://www.eevblog.com/forum/testgear/mso5000/
Help to ID this resistance substitution Decade Resitor box - Page 1
Forum section: electronics / testgear

author: rvalente
author_rank: Frequent Contributor
timestamp: October 20, 2023, 06:36:24 pm
content: Hello Mates,this has come to me as used deal, can someone ID? Its imported my Minipa Brazil, model MDR-610, but which maker?Greetings, Renan

author: BillyO
author_rank: Super Contributor
timestamp: October 21, 2023, 12:44:34 am
content: Just a guess, but I'd say it's a Minipa MDR-610 made by Minipa in Brazil. They have several locations.https://www.minipa.com.br/If it's not, maybe they could help you out. It does not look like anything I've seen before.Is there any information on the back?

author: J-R
author_rank: Super Contributor
timestamp: October 21, 2023, 12:58:06 am
content: LOL, did you actually have to guess, BillyO?

author: BillyO
author_rank: Super Contributor
timestamp: October 21, 2023, 01:04:46 am
content: Well, they do stencil alotof stuff, but I imagine a resistor substitution box might be something they make themselves.

author: rvalente
author_rank: Frequent Contributor
timestamp: October 21, 2023, 01:16:07 pm
content: Nope,allminipa products are rebranded. Their business is to rebrand, change colors, do poorly translated manuals and sell, a lot, here in Br, specially for government and university.Their meters are basically UNITs (low grade) and the good stuff are from Brymen (which Brymen wont take their logo off)And so on, so this decade is not Minipa made, nor looks like Yokogawa (Id love if it was), IET, GenRad, Iskra or other good stuff.Its been sold by 160 USD, which is a lot of money but these things here are expensive and kind rare.

author: AVGresponding
author_rank: Super Contributor
timestamp: October 21, 2023, 03:50:05 pm
content: Any clues, internally?

author: rvalente
author_rank: Frequent Contributor
timestamp: October 23, 2023, 11:55:39 am
content: I've not yet bought it. The idea is to know if its a good investment

author: Gyro
author_rank: Super Contributor
timestamp: October 23, 2023, 01:20:42 pm
content: It looks like an educational one rather than any sort of precision. Probably better then the crappy cheap Amazon ones though.
Follow support instruction to restore firmware - Page 1
Forum section: electronics / testgear

author: Bitmanchu
author_rank: Newbie
timestamp: October 23, 2023, 01:44:33 pm
content: Hi, guys. My Keysight signal generator shows this message, "Follow support instructions to restore firmware" I got in the support Keysight page and they say I can download restoration files, but when I switch my instrument on, no buttons responds. What could I do to fix this issue? May I take out a damaged IC. I would appreciate any helping tip.

author: KungFuJosh
author_rank: Super Contributor
timestamp: October 23, 2023, 02:50:15 pm
content: Try these.

author: coromonadalix
author_rank: Super Contributor
timestamp: October 23, 2023, 05:28:07 pm
content: not really applicable since you need to press some keyscrappy Windows CE loll
Hameg 203-6  - Page 1
Forum section: electronics / testgear

author: Aleksandar_CKU
author_rank: Newbie
timestamp: October 10, 2023, 09:50:50 am
content: On the Hameg 203-6 oscilloscope I have the identical problem pictured here.Video:https://streamable.com/7mmwqt]https://streamable.com/7mmwqt] https://streamable.com/7mmwqtPicture:I don't have the ability to measure high voltage, and it will be quite difficult to disassemble the device and reassemble it. Can anyone tell me where and what I should look at? I can roughly say that I heard something click. It's as if something has become unsoldered or one of the ceramic capacitors is broken.I found an identical problem on the forum, only it concerns the second series of Hameg oscilloscopes:https://www.eevblog.com/forum/testgear/please-help-me-to-fix-hm605-oscilloscope-no-trace/Please help!

author: Zenith
author_rank: Frequent Contributor
timestamp: October 13, 2023, 10:56:06 am
content: I had a similar problem with a 203-6 which turned out to be caused by the unblanking pulse not being set properly. It just needed adjustment. There's a procedure in one of the 203 series manuals which says to use another scope with a 10X probe connected to a -1900V line via a 10nF 2kV capacitor and then adjust a pot to get the correct waveform. I chickened out of the scope part and just adjusted the pot until the trace came right, then went wrong again, and positioned it in the middle of the range where it worked.Of course, it may be a faulty component rather than needing adjustment, but it looks like an unblanking problem.

author: Aleksandar_CKU
author_rank: Newbie
timestamp: October 20, 2023, 07:43:05 pm
content: I found what the problem was. One of the BF199 transistors screamed - T501!

author: Zenith
author_rank: Frequent Contributor
timestamp: October 22, 2023, 09:52:57 pm
content: I'm pleased to hear you got it to work. With scopes you can rapidly get to the point where you need another scope to fix them. It doesn't have to be a very good scope.You might also change the 1000µF smoothing caps in the power supply. You can reach them without removing the PCB. They are notorious. If they haven't failed yet, they soon will.
Leader LBO-518 Scope Y axis drift  - Page 1
Forum section: electronics / testgear

author: Technotronic
author_rank: Contributor
timestamp: October 22, 2023, 04:09:27 pm
content: Someone donated this to me a while back. The voltage / div controls were noisy andthe trace drifts randomly, so I cleaned up the wafer switches today and the controls are less noisybut theres still drift on both channels.The drift seems worse when you do the mag x10 pull on the knobs, eventually the trace floatsall the way off the top of the crt, usually when measuring something. If nothing is measured,and its set to gnd, theres mostly negative drift, moreso if you tufn the knob to lower div settings.Someone linked me to this post:https://www.electro-tech-online.com/threads/2n30809-dual-fet.104271/?highlight=#post851692Apparently those FET's are a common problem, then he I guess isolated an issue with a Hybrid encapsulated ICwhich is likely unobtanium.When the scope is on a short time, the issue is not very prevalent, but seems the longer its on theworse it is so it could be heat related.2N3809 (Q23a/b) looks like a typo on the drawing (pg 38/39). Not sure if thats a dual FET....symbol looks wrong.I found an Analog devices AD3956 as a sub and installed but still have the same issue.Someone said possible leaky caps are allowing DC into the mix...anyone seen something like this before and resolved it?
Racal 9081 Rf Signal Generator - Page 1
Forum section: electronics / testgear

author: Paul Collins
author_rank: Newbie
timestamp: October 23, 2023, 08:25:17 pm
content: A fellow Radio Amateur gave me one of these in good working condition, I let it warm up for around half an hour , took measurements at 5Mhz & 575 MHz, bang on, I'm sure there's loads of other on it which I haven't figured out yet,I also got a Megger Seaward multimeter, the beeper was a bit quite, so I replaced the beeper and all is well, it's accuracy, is off the scale, I feel very lucky owning two pieces of quality equipment. I find it very heart warming, that some people think of you, when they want a clear out.I got from the radio club an 80m receiver that wasn't working, which I got going nicely, very lively, also I got a HP bench multimeter, not working, which is the next thing for me to have a go at, big step for me this one, it has a display reading all 00000000, but No measurement read out if you put in say 9v in NO readout , so the only thing I can think off, is to go through each board one ant a time, repairing, anything I find methodical, hoping to learn lots.
Communications Service Monitor w/ SSB Mode?  - Page 1
Forum section: electronics / testgear

author: Crambone
author_rank: Frequent Contributor
timestamp: October 20, 2023, 03:15:19 pm
content: What service monitor offers SSB mode in the HF Range mostly ham gear for a fair price?

author: geggi1
author_rank: Frequent Contributor
timestamp: October 20, 2023, 07:11:43 pm
content: I bought a Aeroflex 2945B that had this option. Can not remember if this was a software option or a hardware option.For the newer types of service monitors it is probably an software option if they are SDR based.
Rigol DS1054Z - Page 1
Forum section: electronics / testgear

author: StevenWithAVee
author_rank: Contributor
timestamp: October 20, 2023, 04:11:34 pm
content: Hi,Is it possible to enter your own custom math function on the DS1054Z? I am at a loss having looked through the menus, but they are a labyrinth and sometimes I get lost in there.example: I want to enter a function to show dB gain between Ch1 and Ch2 (10×log (CH2 / CH1)).Any help, please?Thanks!

author: Fungus
author_rank: Super Contributor
timestamp: October 20, 2023, 04:20:49 pm
content: Quote from: StevenWithAVee on October 20, 2023, 04:11:34 pmNo.

author: ebastler
author_rank: Super Contributor
timestamp: October 20, 2023, 04:31:22 pm
content: But you should be able to calculate Log (CH1/CH2), without the factor of 10. Use the "fx Operation" to select A/B as the function argument, with A=CH1 and B=CH2; then use Log as the main Math function. See chapter 6 of the manual (August 2016 edition).

author: StevenWithAVee
author_rank: Contributor
timestamp: October 20, 2023, 04:39:47 pm
content: Thanks both!
Determining the resistance of the DCA range. - Page 1
Forum section: electronics / testgear

author: ballsystemlord
author_rank: Frequent Contributor
timestamp: October 26, 2023, 03:14:03 am
content: Hello,Often higher end meters specify the burden voltage of the amps range. For example, 100mV/mA would give us a 100ohm resistor. But some meters only list the voltage drop as a < X.XXX number. Like the attached image.How do I get/approximate the resistance of the meter's amperage ranges?Thanks!
marconi 2031 battery - Page 1
Forum section: electronics / testgear

author: radiofanman
author_rank: Newbie
timestamp: October 18, 2023, 05:40:50 pm
content: I want to buy a new rtc battery for my marconi 2031 but the manual just says a lithium battery, can any one tell me if its a rechargeable or non rechargeable one ie a 18650 3.7v lithium.Sorry about the basic question but the sig gen is buried under a lot of gear and I only want to get it out once to change the battery.

author: SeanB
author_rank: Super Contributor
timestamp: October 18, 2023, 07:55:14 pm
content: Generally a non rechargeable one, with diodes or a power management IC to power the SRAM and a RTC if used, and provide the write protect and CE logic needed to put the RAM in a low power state when power is off.You can use a rechargeable one, but will need to have a method to charge it separately.

author: radiofanman
author_rank: Newbie
timestamp: October 19, 2023, 09:13:20 am
content: ok thanks I think i will get a non rechargeable as I dont want to keep pulling the unit out,I think they last a couple of years anyway.
E4402B can’t use option 1DR - Page 1
Forum section: electronics / testgear

author: RMSLabs
author_rank: Newbie
timestamp: January 13, 2022, 06:16:40 pm
content: I recently picked up an Agilent E4402B SA with option 1DR (narrow resolution bandwidth). The licensing seems to be installed, as the system reports that it does possess this option.My challenge is that I haven’t been able to get the Res BW under 1 kHz. When I step the Res BW down, it stops at 1 kHz and flags the Res BW indicator with a ‘#’ symbol – which apparently indicates the value is now uncoupled. But, it doesn’t reduce the Res BW below 1 kHz.I’ve reduced the span appropriately, so the unit should be able to make this change. Any ideas what I’m doing wrong?

author: cyberdave
author_rank: Newbie
timestamp: October 14, 2022, 02:56:32 pm
content: I have the same problem. I have tried deleting and reinstalling the license key. Did you manage to resolve this?

author: WernerB
author_rank: Newbie
timestamp: October 20, 2023, 04:39:07 am
content: Has anyone solved this issue ? I got one 4402B and ha e the same problem
Teardown of Rigexpert Digital Antenna Analyzer - Page 1
Forum section: electronics / testgear

author: cpuerror
author_rank: Regular Contributor
timestamp: November 28, 2015, 01:26:08 pm
content: I do a teardown of this Ukrainian made antenna analyzer.https://youtu.be/-RnLwJo6vZY

author: usagi
author_rank: Frequent Contributor
timestamp: October 18, 2023, 06:49:24 pm
content: video is gone.
t7 tester issues - Page 1
Forum section: electronics / testgear

author: p.larner
author_rank: Frequent Contributor
timestamp: October 18, 2023, 02:19:27 am
content: my tester does the same as this in the vidhttps://www.youtube.com/watch?v=jnuHhBpvZ4k&lc=UgyewybSEs8CXxuLdDJ4AaABAg.9vqu_ETbAXa9vspix6Bx3Ehas anyone a fix,mine is hardly used,chinese junk i expect!.

author: Kim Christensen
author_rank: Super Contributor
timestamp: October 18, 2023, 03:55:19 am
content: I wouldn't worry about it. Unit is good enough without calibrating it. It's not like it's a precise piece of test gear anyway.If it has a genuine Atmel chip, then you can reflash it with the publicly available firmware. If it uses the Chinese MCU, you're stuck with what you have.
Tektronix MSO 4 Series MSO44 and MSO46 - Page 1
Forum section: electronics / testgear

author: Jay_Diddy_B
author_rank: Super Contributor
timestamp: October 19, 2023, 01:02:47 am
content: Hi group,Does anybody know if it is possible tohackupgrade these scopes?Regards,Jay_Diddy_B
Firmware extraction from Keysight EDU34450A - Page 1
Forum section: electronics / testgear

author: badpork
author_rank: Newbie
timestamp: October 16, 2023, 10:46:13 pm
content: Has anyone done anything similar to this in the past? I'm trying to reverse the web-interface and GUI app running on the multi-meter. I watched the teardown video and I know it has a STM32H75 on it.So far, I've downloaded the firmware from keysight, extracted it from the DFU file, and have a binary image of the firmware. I loaded it into ghidra and followed this tutorialhttps://blog.attify.com/analyzing-bare-metal-firmware-binaries-in-ghidra/to setup the environment. I'm not sure how to go on past this point. There seems to be disassembled code, but I'm not sure how I would be able to find the specific code related to the web-interface or GUI for example.Any help would be appreciated!

author: darkspr1te
author_rank: Frequent Contributor
timestamp: October 17, 2023, 07:21:01 am
content: Hello,Chances are the DFU file is encrypted (although the 32h75 has a dfu boot mode) .i would search for strings first , if you dont find any then it's a high chance the firmware file is compressed or encrypted.with most stm's the first 8 bytes are stack and entry point so i would load a already compiled stmh75 file into ghidra so you can see what a normal compiled bin file looks like and compare the starting bytes between the two firmware files, right away it should be clear that it's encrypted/compressed or plain firmware file if it matches/dont matchdarkspr1te
Are the AN870 & ZT303 still the go to ~25 bucks 4.5 digit & 1uV meters? - Page 1
Forum section: electronics / testgear

author: Rooster Cogburn
author_rank: Regular Contributor
timestamp: October 16, 2023, 05:54:16 pm
content: Basically if you want a cheap all around decent meter that has >=10k count / 4.5 digit / 1uV precision, those are still the two best options? They're also basically the same device?Thanks!

author: Fungus
author_rank: Super Contributor
timestamp: October 16, 2023, 07:52:35 pm
content: Yes.
Brymen BM235 faulty? - Page 1
Forum section: electronics / testgear

author: TopGun82
author_rank: Newbie
timestamp: October 14, 2023, 10:07:09 am
content: Hi all,Since 4 years I have been enjoying my BM235 for some arduino/DIY projects. Since recently though my BM235 is acting up strange. VDC measurements are not showing the correct voltages anymore (way too high):- 1.5v battery measures as 9.46v- 3.9v source measures as 24v- a 12v adapter measures as 76,2- In the AutoV position, the voltages are measured correctly- Also AC is working as expected- I have exchanged the batteries: no changeAny idea what could cause this behaviour? And is it something I could troubleshoot/repair/reset myself?Daniel

author: J-R
author_rank: Super Contributor
timestamp: October 14, 2023, 10:16:46 pm
content: What about the other DC functions, like mV and A/mA?Take it apart and look for visible damage or PCB contamination and check selector switch contacts, etc.

author: TopGun82
author_rank: Newbie
timestamp: October 16, 2023, 01:15:23 pm
content: Looks like mV, A/ma is also not working. First is showing 0L, the currents are showing 0.I opened it up, but could not see something out of the ordinary.

author: J-R
author_rank: Super Contributor
timestamp: October 16, 2023, 05:56:46 pm
content: On this unit you will have to unsolder the input board from the main PCB in order to remove everything and access the selector switch and contacts. Also, be sure to carefully inspect all solder joints and components from different angles, maybe with a microscope. Can't tell, but is there something up with D7?

author: mwb1100
author_rank: Frequent Contributor
timestamp: October 16, 2023, 06:04:37 pm
content: Quote from: J-R on October 16, 2023, 05:56:46 pmAlso D14 looks like a similar part, but one end is blackish - did the smoke get out?

author: mwb1100
author_rank: Frequent Contributor
timestamp: October 16, 2023, 06:22:22 pm
content: D7 does look different on my BM235 (it looks more similar to D14 with black on one end).

author: J-R
author_rank: Super Contributor
timestamp: October 16, 2023, 07:05:02 pm
content: Lighting can play tricks too...
10 MHz photodiode? - Page 1
Forum section: electronics / testgear

author: Dave92F1
author_rank: Contributor
timestamp: October 16, 2023, 04:24:39 pm
content: I want to make an optical probe for an oscilloscope, to measure flash duration from a stroboscope.The flashes are on the rough order of 1 uS each, so I'd like about 10 MHz of bandwidth. Noise and gain aren't too critical (I'm mostly interested in timing, not light quantity).Also, I'm lazy, so it would be great to find an integrated photodiode/amplifier in one part, like the TI OPT-101 (only much faster; the OPT-101 tops out somewhere around 50 kHz depending on the feedback resistor).Suggestions?

author: TimFox
author_rank: Super Contributor
timestamp: October 16, 2023, 04:50:32 pm
content: I don't have a suggestion for a pre-made integrated unit.In general, to get a fast response from a photodiode, you want to apply a reasonable reverse bias to the series combination of the diode and a 50 ohm load (which can be at the 'scope input, but must be DC-coupled to complete the circuit).The usual figure for the sensitivity of a silicon photodiode is 0.4 A/W: do you know the light output of your stroboscope and the optical geometry?

author: Kleinstein
author_rank: Super Contributor
timestamp: October 16, 2023, 04:53:38 pm
content: With a flash there is no need for an amplfier. The photodiode could directly work on some 50 or 100 ohm impedance, e.g. from the scope or a termination close to the sope.For better speed one may want bias the diode in reverse, e.g. from a 9 V battery with a local capacitor (e.g. 100 nF) for the RF return path around the battery and towards the coax cable.I have seen such setup used for sub µs laser pulses and a GHz BW scope.
Do most 6.5 digit DMMs measuring amps in the noise? - Page 1
Forum section: electronics / testgear

author: ballsystemlord
author_rank: Frequent Contributor
timestamp: October 16, 2023, 04:59:51 pm
content: I rewatched Dave's video on how to choose a DMM and applied the info to the amperage of DMMs. Here:At offset 35:30 he talks about accuracy and says to use the formula, 10/counts * 100 == % to determine what the minimum accuracy of your scope should be.Now if we apply that to a 6.5 digit DMM: (10/1200000)*100 == 0.00083 .Then if we go over to the fine list of Bench DMMs here:https://www.eevblog.com/forum/testgear/multimeter-spreadsheet/We see that most of them 0.05-0.03 or higher for the amperage range of the DMMs.So, is it just me, or do most 6.5 digit DMMs measure amps in the noise?Thanks!EDIT: Actually, it looks like they measure voltage in the noise as well...

author: Kleinstein
author_rank: Super Contributor
timestamp: October 16, 2023, 05:41:33 pm
content: The formular for the accuracy is a rought guide, usually for the DC voltage as the easiest case. It still is not a strict requirement and does not fully apply to very high resolution ones.The current measurement is more tricky and is usually less accurate for 3 reasons:1) the heating of the shunts2) the need to measure relatively small voltages like in the 100 mV range3) the difficulty to get proper 4 wire contacts with shunts in series as the usual configuration.So it is quite normal to see a lower accuracy for current and rarely a reduced number of digits.More digits than accuracy can still be useful, especially at the lower end of the range.Things have also changed over time: just the resolution got cheap with SD ADCs. Noise is a 3rd parameter to look at for the quality.The expectations are a bit different for a 6 digit meter compared to a 2000 count meter. For the lower resolution one usually wants hardly any visibler noise or peak to peak noise less than 1 LSB. For the higher resolution ones usually 1 LSB RMS noise and thus a 6 times high limit is considered the usual benchmark.
Software for Rigol DS1054z - Page 1
Forum section: electronics / testgear

author: ulfh2012
author_rank: Newbie
timestamp: October 15, 2023, 06:32:47 pm
content: I know there is a lot of information about the sofware written by Marmad, and I have spent a lot of time reading, but I cannot find the location where I can downlod what I need. Can someone please helpe me, and if possible do not just say "it's in the Forum"Best regardsUlf H.

author: ebastler
author_rank: Super Contributor
timestamp: October 15, 2023, 06:40:25 pm
content: A .zip file is attached to the post below. It's old though, not sure whether any more recent versions are around?https://www.eevblog.com/forum/projects/software-tips-and-tricks-for-rigol-ds200040006000-ultravision-dsos/msg171692/#msg171692

author: coromonadalix
author_rank: Super Contributor
timestamp: October 16, 2023, 01:46:50 pm
content: i think it for the higher 2k models etc ...link of the v2 ..https://www.eevblog.com/forum/projects/software-tips-and-tricks-for-rigol-ds200040006000-ultravision-dsos/?action=dlattach;attach=73265link of the v3 alpha seems dead ??there is this threadhttps://www.eevblog.com/forum/testgear/rigol-screen-capture-vcl-windows-application/msg5108583/#msg5108583RSC_v0.3b works very well on our Rigol 1000 series, a life saverattached zip file

author: tv84
author_rank: Super Contributor
timestamp: October 16, 2023, 01:51:22 pm
content: @PeDre's tool continues to be one of the most simple and bullet proof tool for SCPI commands.

author: coromonadalix
author_rank: Super Contributor
timestamp: October 16, 2023, 01:58:19 pm
content: yesRUU .... in my case does not work for a DS1104Z Plussome models doesn't support some screen capture commands if i recalli salute people who can create theses softwares, kudos to them
Good Quality Variac with Isollation - Page 1
Forum section: electronics / testgear

author: 2X
author_rank: Frequent Contributor
timestamp: October 14, 2023, 08:43:42 pm
content: Hello,do you know any good brand of Variac with isolation between input and output voltage? The only I found is a red one from China and I am not sure that it has isolation.Also I found this which is a complete power supply:https://www.peaktech.de/uk/PeakTech-P-2235-Control-isolating-transformer-1000-W-0-30-V-5-A/P-2235MA 4804 Power supply (I asked for this in a local store and told me that is no longer in production)https://metrel.co.za/shop/equipment-for-laboratories-and-schools/ma-4804-power-supply/

author: ddrl46
author_rank: Regular Contributor
timestamp: October 14, 2023, 08:56:21 pm
content: I've had good experiences with the EA-STT 2000B-4.5 from Elektro-Automatik:https://elektroautomatik.com/shop/en/products/industrial-power-supplies/ac-sources/power-supplies-variable-and-isolating-transformer-ac-dc/232/transformer-0..260v/4.5This unit is fully isolated, slight downside is the slow update rate on the display. This can however be improved somewhat with a slight modification.

author: johansen
author_rank: Super Contributor
timestamp: October 14, 2023, 10:54:50 pm
content: I cant say this for certain but i have no memory of ever seeing an isolated variac, that is, a variac winding over the top of the primary coil, which is a shame because traditional variac transformers are rather inefficient by weight, due to the difficulty of getting a high copper density. It would be rather easy to fit a primary coil under the secondary variac, if the inner diameter of the core were increased a bit so that the secondary coil is a standard 2:1 inner to outer ratio suitable for machine winding a variacI had a burned up 0-260vac 10 amp rated variac, i rewound it with 15 gauge wire and i think i can get 140vac out of it at 4 watts of no load losses.I think the original 260vac winding was 20 gauge wire, but it might have been 18.

author: johansen
author_rank: Super Contributor
timestamp: October 18, 2023, 07:37:21 pm
content: They exist.https://www.amazon.com/Variable-Transformer-1000VA-Isolated/dp/B09X153FZW
Standarized multimeter testing process with cheap equipment. - Page 1
Forum section: electronics / testgear

author: jemarro12
author_rank: Contributor
timestamp: October 15, 2023, 05:32:47 pm
content: Hi guys,which will be the best approach of a good and repetible test to apply for different multimeters?I own a youtube channel and analyzing different test gear, from portable cheap dmms to 5.5 digits bench dmms.From now i generate different signals from a relatively stable source (Rigol DG992) and using my most recent calibrated multimeter as control reference, compare the results with de DUT (usually cheap dmms)I´d like to standarize a test to apply always the same tests to the DUTS, and maybe post results in excel format.What would be the most optimal laboratory instruments to standardize the tests within a logical budget?Thanks!!

author: alm
author_rank: Super Contributor
timestamp: October 15, 2023, 05:53:44 pm
content: You don't specify "logical budget". If you want some spot checks, I'd suggest looking into theDMMCheck Plus. If you want to test the full range, then I'd look for a usedFluke 5100/5101 A/B. If you're patient, you might be able to get it for something like €1k plus a few hundred € shipping. It's huge, heavy and might need some repairs given its age, though. I'm not aware of a cheaper option that can test all ranges of a multimeter. It can be operated via GPIB if you get one with the right option. If you want to buy the same new, consider a second mortgage on your house.Otherwise I'd use a programmable power supply for DCV and DCI, a function generator for ACV and ACI (limited current range), and make a board with a bunch of decent resistors and banana jacks to test resistance. Something like theToellner device offered heremight also work for low frequency ACI. But testing 5.5 digit DMMs this way is a bit of a challenge because these sources may not be stable enough. I have done it, and what I had to do was to hook up two meters in parallel / series, record over a long time, and then calculate correlation coefficient between the two meters. Also, it limits voltage ranges for both DCV and ACV to about 30V DC and about 7 Vrms AC. For DCV you can put multiple channels / power supplies in series, and higher voltage power supplies aren't so hard to come by. But I haven't found an easy way for generating ACV up to say 750 Vrms 1 kHz outside dedicated calibrators.For consistency I would try to automate as much of the test as possible. Hence my suggesting programmable equipment. Just have the automation prompt for the measured value if the device under test does not support remote control (like most handhelds).
Hantek DSO5102P single shot not always working - Page 1
Forum section: electronics / testgear

author: Cookie13!
author_rank: Newbie
timestamp: October 15, 2023, 12:16:42 pm
content: I am an amateur as far as electronics is concerned. I am trying to capture a key sent from a terminal emulator to a UART on the scope using the single shot facility. I have followed the procedure in the manual. Sometimes it works. After making the settings in the acquire menu, i press the single shot button which lights up and stays on until i send a character which it correctly captures and the light on the button then goes off. in other cases the single shot button blinks on when pressed and off immediately so it is not possible to capture the character. Any idea what could be causing this?

author: adam4521
author_rank: Regular Contributor
timestamp: October 16, 2023, 01:29:49 pm
content: Assuming you are using edge trigger, is the trigger level correct? It needs to be different to the quiescent signal level otherwise it will trigger immediately or randomly. For serial comms try setting it in-between the mark and space voltage levels.
Initial checks for Tektronix P6042 Current Probe? - Page 1
Forum section: electronics / testgear

author: Stray Electron
author_rank: Super Contributor
timestamp: October 15, 2023, 04:13:40 pm
content: I picked up two of these last week and before I power them up I was wondering if anyone had any suggestions about anything that I should check first. Judging from the stiffness of the power and probe cable I don't think either of these has been used in many years. The probe cable on one of them has been cut off ab out 5 inchesinsideof the chassis so I know if will need repair. I have read the other threads on her about the cracked probes and broken probe cables so I'm already aware of those potential problems. I'm also already planning on checking all of the electrolytic caps in them.I'm also considering removing the (socketed) M18 amplifier before powering them up and I can fully check the power supply voltages. Good idea or not?
Owon HDS2202S unrest at idle state - Page 1
Forum section: electronics / testgear

author: u666sa
author_rank: Frequent Contributor
timestamp: October 12, 2023, 09:35:19 am
content: You see, I only now began paying attention to this.So I don't know if it's good bad normal not normal, is it broken or not.Basically, when I turn on oscilloscope, and it's an idle, no probes connected. V says -.414 and it goes up and down, V is mean. RMS also around 500 going up and down.Then when I connected a AA battery, with known voltage of 1.6108 and connect probes to it (DC couple, 10x, full 200 Mhz band) I get this:As you can see V voltage of battery minus whatever V was before. Is that suppose to be like that?Then, let me turn on wave gen, 1.0000kHz, 1.00VppVpp says 1.080V and it goes up and down 1.060, 1.080, V is 017, -11.60, goes up and downAnd here is screenshot at rest, plus attached wave .cvs at restIs this normal? Or, do I have a problem?
Brymen BM197 vs BM089 - Page 1
Forum section: electronics / testgear

author: TheGrave
author_rank: Contributor
timestamp: October 14, 2023, 05:41:22 am
content: I'm hunting for a new clamp meter, budget up to 200-250EUR excl. VAT, must be sourceable in Europe or USA. I own a UT61E and a UT210E. Both are good units but I need to measure some DCA in excess of 100A so I hunted down the options I have and realized I either need to sacrify features to get a named brand unit (Fluke, Benning, Kyoritsu, Megger) or spend tons of money which I cannot excuse for non-professional use (and precision is not of great matter in my case but safety is). Here is what I'm currently missing in UT210E and ideally like to have:1) Better and longer lasting backlight2) Measurement in the range of 100-300DCA3) In-rush current detection in excess of 800DCA for checking diesel engines and fridge compressors startup currents. Not sure if 80msec will be good enough for a fridge compressor though?4) MAX/MIN values with as high sampling rate as possible5) True RMS6) Dual voltage+current display as I often need to make such measurements7) Clamps that can take up to 95mm2 cablesOptional - NCV (I know it's not reliable in most clamp meters)9) Optional - 12h data logging for detecting leaks.After almost paying for a Fluke 325 I saw some not so glamorous reviews about it and decided to give it one more try in the forum for alternatives so I arrived at Brymen. Models that caught my eye are BM197 and BM089. Very few reviews or first-hand info for both units, no teardowns so I'm naturally a bit cautious. Anyone played around long enough with any of them?Got 2 questions about these units:1) The 3-phase motor direction detection on the BM089 - I saw how the feature works on AC motors. Wondering if there is any chance it works on DC 3-phase motors too? I have an electric motorcycle (Surron LightBee) so god forbid I need to troubleshoot it one day but such a feature might come handy.2) BM089 can measure between 60A and 1000A and BM197 can measure between 200A and 2000A, am I reading the specs correctly?I'm open for other alternatives too but I think I exhausted the options in my price range an I either need to settle for a 600A unit without a dual-display & in-rush current detection or get Brymen. I also checked some CMM units but they have horrible problems reported.
UNI-T UT181A converted to use 18650's - Page 1
Forum section: electronics / testgear

author: 1waynger1@gmail.com
author_rank: Newbie
timestamp: October 17, 2023, 05:16:37 am
content: I have a Triplett 9065 that is really a version 6 of a UNI-T UT181A. For several years now it is my go to when a fluke 87 or a BM869s can't do what I need. But.... It is a pain in the ass to charge, and if it lays around for months unused the battery will fully discharge.So I 3D printed a new slightly larger back, that protrudes no further than the pivoting support flap on the rear of the unit.This gives me enough room to put in a pair of 3200 MA 18650 cells in the correct cell holders.Installed a 3 wire charge port that a 2 cell USB powered charger connects to allowing balanced charging.Installed a low tech slide switch to allow disconnecting the 18650's if the unit is to be stored for extended periods.With this setup I can charge, of course, any time the switch is off or on and even while the meter is data logging, that charge position of the main rotary dial can be forgotten.It has worked out well with no increase in size testing to see how long it will datalog.Here are a couple pics of the prototype back.If one wants to make their own I can email the .3MF file, you will also have to cut out a window in the support bail on back of unit.https://photos.app.goo.gl/YdLiXHosnZ6VAQRd9
BNC To Kelvin Clip Leads - Page 1
Forum section: electronics / testgear

author: Bhavi
author_rank: Newbie
timestamp: October 14, 2023, 02:23:18 am
content: Hi guys, I need some suggestion on which BNC to Kelvin Clip leads is best for the price range within 500 USD and frequency rage 1kHz till 10 MHz

author: KungFuJosh
author_rank: Super Contributor
timestamp: October 14, 2023, 03:27:42 am
content: What are you connecting them to?The TongHui Kelvin leads are excellent if the spacing will work with your meter. Careful not to get a counterfeit though. OTOH, other legit companies rebrand the TongHui stuff and charge more for it.