hybridfree/eevblog-posts huggingface dataset:
Using Keysight 2000 scope as datalogger - Page 1
Forum section: electronics / general

author: tchicago
author_rank: Regular Contributor
timestamp: October 24, 2020, 05:31:37 am
content: Hello, All,From time to time, I need to log some slowly changing processes, like discharge curves of the battery, etc. Although the dynamic range of scope is not that good, using oscilloscope for this is still particularly good because it allows to set up the range for all inputs so that it will be measuring exactly what I need. I figured out that my Keysight 2014A oscilloscope has a USB device connector, i.e. can be connected to USB host on a PC. Ideally, I'd just want to initiate reads of the current ADC value from the specific channel of the scope, repeating the reads as necessary. That's all. I can write some scripts, C#, C++, Excel macros, whatever.So I connected the scope to PC using USB, and then found some software DVD image from Keysight with all kinds of software on it. I tried installing some from there, like BenchVue, IVI, etc, and they are all super-complicated software packages built of dozens of components, most of which require additional license to operate.I learned that there is some industry standard SCPI interface, that can probably give me what I need. However, I'm not sure which exact parts of those huge software packages I need to install, and how to use its API.If anyone has already investigated this path, could you advise what's the minimum software setup for this? Maybe there is some guide and examples already. Just in case, my scope does not have a LAN port, only non-host USB on the back.(I know that data logging into the USB Flash drive is another possibility, but for many reasons, I want to be in control of the process from the PC side)

author: petemate
author_rank: Regular Contributor
timestamp: October 25, 2020, 02:17:15 am
content: I would say that minimum effort is python with PyVISA to control your device. You basically connect your scope using USB/gpib/rs232/lan/whatever and send commands in plain text using the PyVISA modules.A scope doesn't return "one" ADC value from each channel. It reads hundreds or thoudsands of times for each trigger and stores those values. You should be able to send a command to download those to the computer running your script(using a command like ":waveform:data?") or save them on e.g. an usb stick in the scope(using a command like ":save:waveform"). You'll need to consult the programming manual(https://www.keysight.com/upload/cmc_upload/All/2000_series_prog_guide.pdf) to see all the features, but there are many. It will take some time to understand how the syntax work and how to work with it, but its not that hard.Edit: Link to pyvisa with many examples and helpful tutorials:https://pyvisa.readthedocs.io/en/latest/

author: Kibabalu
author_rank: Regular Contributor
timestamp: October 25, 2020, 04:39:26 am
content: have a look athttps://github.com/sgoadhouse/msox3000It works also for my DSO-X 2000 series model.
Keithley 6485 Test Leads: Keithley 7754-3 - Page 1
Forum section: electronics / general

author: leighcorrigall
author_rank: Frequent Contributor
timestamp: October 21, 2020, 07:56:31 pm
content: Hello everyone,I have been waiting for weeks to receive a 'specialized cable' for my Keithley 6485 picoammeter. It cost 115.20 CAD + tax. When it arrived in the mail, I was expecting something different. See attachment.By inspection, I was surprised to see that it was a basic looking Pomona cable. Naturally, I checked the mouser website and found that the Pomona 4532-C-36 is available for 34.66 CAD!!!Buyer beware. I am contacting the technical support depart at Mouser to determine if a mistake has been made. Hopefully, I can help others by sharing what I know.Is this unethical for Tektronics to do this? Should I return the part for a longer and cheaper version (4532-C-60) or are there some differences in the manufacturing process that I am not taking into consideration?Thanks for your support!

author: LaserEng
author_rank: Regular Contributor
timestamp: October 22, 2020, 06:00:20 am
content: It's just a case of Tek adding their expected margin on the cable and accesories typically are hit with the largest margins to cover costs, is it unethical, no but it does leave a bad customer experience. Surprised they couldn't be bothered to hide the OEM though.

author: notfaded1
author_rank: Frequent Contributor
timestamp: October 22, 2020, 03:42:51 pm
content: Yeah the longer 60" Pomona version is 2$ more vs 36" one. $25.99 vs $23.99 USD. It would be hard not to want to return it I think. You could have one of each for less. I have one of the 36" Pomona ones I bought off ebay a while ago. I always thought it was a little weird the one lead was longer?Bill

author: leighcorrigall
author_rank: Frequent Contributor
timestamp: October 22, 2020, 04:01:37 pm
content: Quote from: notfaded1 on October 22, 2020, 03:42:51 pmHi Bill,This is a good question.The reason for the shortened red lead is to keep electrical interference exposure to a minimum of the inner conductor (HI input). The length of the black lead (LOW input) is less important for a grounding shield and the length needs to be greater so that you can attach a potentially large DUI. I wish they shielded the red lead all the way to the end like they do with the triax alligators (eg. 237-ALG-2, 2600-ALG-2), but alas, it's too expensive for most applications.
Not quite room temperature superconductivity yet but getting closer... - Page 1
Forum section: electronics / general

author: notfaded1
author_rank: Frequent Contributor
timestamp: October 20, 2020, 07:53:50 pm
content: https://singularityhub.com/2020/10/19/scientists-just-achieved-room-temperature-superconductivity-for-the-first-time/Could we be saying goodbye to resistance at room temperature in the near future? I like this line:The researchers are also still unclear about the exact nature of the material they have made.Bill

author: Grandchuck
author_rank: Super Contributor
timestamp: October 20, 2020, 07:58:56 pm
content: Thanks Bill. Maybe basement JJA voltage references are coming

author: Kleinstein
author_rank: Super Contributor
timestamp: October 20, 2020, 08:18:19 pm
content: For the near room temperature superconductivity they need an extreme pressure. It is much easier to get a low temperature (e.g -200° C range and likely also the 4 K range) than getting that enormous pressure.With the high pressure they are also limited to tiny size. It may help a little with research, but I see no real break through.I don't see any direct consequence to practical application.Already the so called high temperature superconductors that work at some 50-100 K behave a little different from the low temperature ones. So far no Josephson junction array working at 77 K, though there are a few squids to work at 77 K and they may be useful in a not so exotic superconducting current comparator. 77K still sounds pretty cold, but it's a whole lot easier than 4 K. A quantum reference working well at 77 K would be a more relevant break through.

author: notfaded1
author_rank: Frequent Contributor
timestamp: October 20, 2020, 08:42:33 pm
content: You're right... they say 15 degrees celsius but the team was only able to create a tiny amount of the material, roughly the same volume as a single droplet from an inkjet printer. And to get it to superconduct they had to squeeze it between two diamonds to create pressures equivalent to three-quarters of those found at the center of the Earth. Amazing they aren't even sure what the material they created is. Still it's interesting to think that a real breakthrough could be made and we might live to see some really new practical applications. Really it's research like this (well research at least) that brought us the JJArray. Yeah an array that could run at warmer temps would be big and make things cheaper to operate I would think too.Bill
EFC fine tuning circuit - Page 1
Forum section: electronics / general

author: tkamiya
author_rank: Super Contributor
timestamp: October 14, 2020, 12:47:28 am
content: HP11081 has both physical tuning and EFC. On EFC, I can apply +/-5V to swing as much as 10Hz on some models. However, that means tuning rate is VERY fast even with 10 turn pots. I do need an ability to swing to both extreme and have fine tuning capability using EFC only.So I'm trying to come up with a setup where there is a coarse and fine tuning of EFC. Cascading pots didn't work very well. Fine tuning rate isn't constant depending on where main VR is positioned. Does someone have a creative solution?

author: fourfathom
author_rank: Super Contributor
timestamp: October 14, 2020, 03:16:15 pm
content: You might try something like this. The resistance values can be change as appropriate for your EFC input impedance, what I am showing is the topology where one pot has a 10x (approximately) influence over the control voltage. The "vernier" pot can have a higher resistance than the "coarse" pot.

author: tkamiya
author_rank: Super Contributor
timestamp: October 14, 2020, 05:47:31 pm
content: Wouldn't that circuit form a voltage divider at the additive network (registers) though? The way I'm reading it, 1K VR forms variable voltage from single source, the difference between the two will become the input to 10:1 register divider. The maximum voltage I can get out of that will be 0.5V. Or, am I reading that wrong?

author: 5065AGuru
author_rank: Frequent Contributor
timestamp: October 14, 2020, 05:57:01 pm
content: Taka,The +- 10Hz range on a 10811 is via the coarse tuning capacitor thru the hole in the case.The EFC only ranges a 1Hz total range over +- 5V.I normally just uses a 10K pot in series with a 500 Ohm pot in the ground leg.I drive them with an LM399AH unless the oscillator provides it own low TC reference voltage out.Cheers,Corby

author: tkamiya
author_rank: Super Contributor
timestamp: October 14, 2020, 06:13:12 pm
content: CorbyThat's true for most models of 10811. However, there are models that will do much more. Types used in HP's GPSDO and Cs will do half of mechanical range in EFC. The one I have, and I don't recall where it came from actually does full swing. Your method makes sense though. I'm using a 3 terminal regulator as HP usually does. Perhaps that will need to be improved for my purpose.

author: fourfathom
author_rank: Super Contributor
timestamp: October 14, 2020, 07:09:37 pm
content: Quote from: tkamiya on October 14, 2020, 05:47:31 pmI should have put reference #s for the resistors and pots!The circuit is a voltage divider of sorts, but you can still get the full 0-5V range from it. With the left-hand pot (course) set to 50%, adjusting the right-hand pot (fine) will give an output range of 2.5V +/- 0.227V. With the coarse pot set at max (5V) the output voltage will be between 4.545V and 5V. You can change the ratio of the fixed resistors to give you a larger or smaller fine-tuning range.
Proskit MT-2017 is real bad? - Page 1
Forum section: electronics / general

author: jdm1
author_rank: Newbie
timestamp: October 01, 2020, 05:34:38 pm
content: Please excuse if my question is so much below the normal level of this board.I have got the meter in subject mainly because it has a null DCV mode which I tought was good to check circuit pulse output on quartz watches. That little I achieved, but in regular DCV mode on the smallest range.Then I went to measure a brand new alkaline battery which reads an hair below 1.6V on my digital meter, I get 1.3V on the analog instrument. That is 0.3V error, or 12% FSD, where specificatations promise + / - 3%. And in battery test mode it barely gets to "good".The unit is really big compared to what I had or seen until now, all in all I am a bit disappointed.Is that kind of expected with cheap meters like this?Could be due to a defect which I can repair myself?Would a Sanwa, or other meter, do better?

author: tkamiya
author_rank: Super Contributor
timestamp: October 02, 2020, 08:33:34 pm
content: Quality analog meters are much better than what you are seeing.But when you buy an inexpensive Chinese made meter, anything is possible. Same model vary quite a bit from piece to piece, too. Can you send it back for exchange or refund? There isn't much hope in fixing something like this.

author: jdm1
author_rank: Newbie
timestamp: October 02, 2020, 08:53:34 pm
content: Thank you for your answer. I am not concerned at all about the monetary aspect, a mere €20, incidentally I am fully covered by the aliX and the C/C issuer.But i like to understand how things work, why they fail and how to repair them if possible, all that indipendently from their origin or value. I will try measuring some resistors to see if the problem is the same, which I think would indicate a defect in the dial meter, as opposed to one in circuitry.

author: tkamiya
author_rank: Super Contributor
timestamp: October 02, 2020, 09:00:31 pm
content: Sure. If you are going to use that as an educational tool, by all means, go right ahead!I would guess though, the fault is likely be in resister that's awfully off specification. Keep in mind, analog meter has an error spec different from digital ones. Most of them are 5% of full scale.Say you are at 10V range. 5% of full scale is 0.5V. If you are measuring something that's 1.5V, the actual reading can be anywhere from 1.0V to 2.0V and that's still within specification.

author: jdm1
author_rank: Newbie
timestamp: October 04, 2020, 10:15:19 am
content: Sorted with few pats on the back.
Board for Furuno GT88? - Page 1
Forum section: electronics / general

author: WPXS472
author_rank: Regular Contributor
timestamp: October 02, 2020, 08:11:19 pm
content: Does anyone make a board that would work with the Furuno GT88 GPS ? I have one that I would like to experiment with, but no board to attach it to. Furuno sells a kit that includes the board, but it is way out of my price range.
Wavecrest DTS2070 PAC-1A - Page 1
Forum section: electronics / general

author: rubidium
author_rank: Regular Contributor
timestamp: September 28, 2020, 08:28:21 pm
content: I picked up this colossus recently for essentially the cost of shipping, and it arrived today - along with the specter of a hernia.It's in great physical shape, it powered on, all of the DC voltages measure within spec, no burnt or leaking passives, and it performed its 300 sec internal calibration without a hitch. I have the user's manual, but it's rather light on detail. I also have no clue as to what the "PAC-1A" nomenclature means. So there's a lot of exploration to perform. For now, I simply hooked up 2 same-length RG-58 lines to the internal 200MHz cal outputs and performed the external cal procedure for cable compensation. The result is shown in the display, and it's rather amazing how just turning one of the SMA connectors just a fraction of a turn is *easily* sensed and quantified by this instrument.I did notice that the internal 100MHz OCXO was off by about 13Hz. There is a multi-turn pot inside the OCXO that is accessible, and I can adjust it to be within a few 10'ths of a Hz of 100MHz, but, magically, there appears to be a glitch in the pot at that very point so I can't do much better. I suppose after I spend more time navigating about this system, I can perhaps get inside the OCXO and replace the pot.This may not be as heavy as my HP8664A, but it's damn heavy.Jim

author: wn1fju
author_rank: Frequent Contributor
timestamp: September 29, 2020, 11:42:23 am
content: I have the DTS-2075 and it is a wonder of technology. Not sure how it differs from your 2070 (nor do I know what PAC-1A means) - maybe the 2075 can do a bit higher frequency?Anyway, in case you haven't found this already, go to KO4BB's site, go to the manual section and search on "wavecrest". You will see tons of application notes and near the bottom is a .zip file containing a lot of useful information on these digital time scopes.

author: rubidium
author_rank: Regular Contributor
timestamp: September 29, 2020, 11:59:36 am
content: Quote from: wn1fju on September 29, 2020, 11:42:23 amFrom the various user's manuals, the older 2070 and the more recent 2075, 2077, and 2079 don't differ a whole lot in terms of resolution. The later models accommodate higher frequency and have more memory to store measurements.The unit i have is very clean and appears to be fully functional. My only qualm is that the internal 100 MHzOCXO has drifted nearly 3 Hz overnight and apparently still hasn't settled down. Perhaps the unit has been idle for a long time and needs to be under power for a significant period before things settle down. There's also the issue of the OCXO adjustment pot. There's a glitch right around the spot you want to calibrate to, and smoothly adjusts the frequency everywhere else.Jim
Anyone here owns a Fluke/Wavetek 7004/7010 System? - Page 1
Forum section: electronics / general

author: Echo88
author_rank: Frequent Contributor
timestamp: September 23, 2020, 10:43:57 am
content: Im interested in the construction details of the Fluke/Wavetek 7004 or 7010 Voltage Reference System:https://xdevs.com/doc/Wavetek/7000/7000____umeng0100.pdfTiN already did teardowns of the 7000-Module (Reference module itself) and the 7000S-Module (makes it possible to connect external voltage references to the system), which is already very nice:https://xdevs.com/doc/Wavetek/7000/img/Now im especially interested in the 7000N-module - basically the heart of the scan-system as it contains the RS232-communication, scanner and the nullmeter.Sadly due to the scarcity of such systems ive never come across a person owning one, thats why i wanted to ask here if anyone owns the 7000N or the whole 7004/7010-system (backplane and 7000T-module would also be interesting) would be willing to do a teardown of the unit.Id be willing to encourage the teardown with up to 100€ for detailed teardown photos of the pcbs (both sides to determine traces and components) or a bit less for some rough photos of the overall construction and pcbs to determine how they implemented the nullmeter and other stuff.
Help with calibration pots identification. Siemens oscillar MO7192 - Page 1
Forum section: electronics / general

author: grusus
author_rank: Regular Contributor
timestamp: July 30, 2020, 12:23:20 am
content: Hi.Can anybody please help me with identification what is what in scope that I have recently repaired? This is old Siemens scope from 1975. It is my personal scope. Ibought it cheap in 2006 - never was working correctly until now - so I decided to calibrate it, but I have some question marks on what those pots are. I am quite new to scope repairs and any help will be apreciated.Manual with schematics (french+partialy english) is here (it was released also as Schlumberger CRC 5041/5043):https://drive.google.com/file/d/1xSEd64FWdFMlail6zve46SnYoJvqsXur/view?usp=sharingI have marked in red rectangles things that I am not 100% sure or don't know:C4,7,11,15,19,25 are trace compensation overshoot/undershootC1,5,9,14,16,20,23 - are those input capacitance compensation?R35&R79 I think are vertical gain for ch1&ch2R116 is some king of waveform symetrization?R100 makes trace to shorten vertically - what is propper name for that?R31,R33,C6,C8 - looks like delay line comp (behaves that way when 1MHz square is at input of ch1)C18,R77 - looks like delay line comp (behaves that way when 1MHz square is at input of ch2)R137,C29,R138 - also affect traces like some kind of delay line compensation, but affects both channels.C2 - trigger 1 - 1/10 compensation?R6 - ?R25 - ?R62,R63,R64 - Adjustment of horizontal gain for different timebase settings?R75 - ?R87 - ?R97 - ?R99 - ?R104 - ?R112 - ?There is no service manual for this scope. I digged everywhere for it and found only manual from link above. I know procedures how to calibrate scope from tek scopes manuals.Many thanks for everyone in advance.

author: Didgitalpunk
author_rank: Contributor
timestamp: September 21, 2020, 12:58:35 am
content: Hi,Maybe try asking this guy for a manual:https://electropuces.pagesperso-orange.fr/He doesn't list it on his site, but he might still have a copy around to sell you. they're not too expensive, around 20euros without shipping.Another option if you have someone in France that could scan it for you, it is available for lease here:http://www.radiofil.com/schematheque/schlumberger-5041,m38045.htmlthere's two documents available, one that's 225grams, which I think if what you have in PDF, and one that's 990grams, which I'm sure contains much more info that the PDF you have.In my experience Schlumberger manuals from that time frame are supposed to be way more complete than that, including picture of the PCBs and machine, and an entire maintenance section that's pretty much a third of the page count. my guess is whoever posted this PDF either didn't want to scan all of it, had an incomplete manual, or just a slimmed down user manual from the original.Best of luck,Francois Mutschler
Tinysa, spectrum analyzer - Page 1
Forum section: electronics / general

author: Diabolo
author_rank: Regular Contributor
timestamp: September 17, 2020, 02:08:22 am
content: Hello,New product to discover:https://tinysa.org/wiki/pmwiki.php?n=Main.HomePageRegards,Diabolo

author: Gyro
author_rank: Super Contributor
timestamp: September 17, 2020, 09:11:47 am
content: There's already a thread in a more appropriate place (as you already know) ...https://www.eevblog.com/forum/testgear/tinysa-spectrum-analyzer-by-hugen/There's another in the RF section:https://www.eevblog.com/forum/rf-microwave/tiny-sa/

author: Diabolo
author_rank: Regular Contributor
timestamp: September 18, 2020, 01:36:03 am
content: Hello,Oups, sorry, I didn't pay attention.I will go to the topics dealing with Tinysa.RegardsDiabolo
Burster KELVIMAT 4323 teardown - Page 1
Forum section: electronics / general

author: doktor pyta
author_rank: Frequent Contributor
timestamp: September 15, 2020, 10:51:40 am
content: What does Isotech / ASL F150, Cropico 3000 , Burster 4323 have in common?They share common design.I suspect ASL to be former designer because they had experience in making highest class thermometry bridges.I wrote 'had' because ASL was acquired by Tinsley, Tinsley by Wika.Also the Isotech/ ASL user's manual is most comprehensive among others.Item bought as parts unit.After examination I figured out that there are two SLA batteries -one for analog, one for digital and one lithium for RTC/ NVRAM- and what is important, the instrument won't turn on if the akkus are discharged. Even if it is mains powered.I applied external power supply (to mimic charged akkus) and saw this:Below photos of the guts.PCBs are nice, tidy, no bodge wiring. But these two akkus... well let it be.ADC section based on HI7190IP.Custom wire wound reference resistor 400 ohm.Cropico name on the PCB.

author: Vgkid
author_rank: Super Contributor
timestamp: September 16, 2020, 04:40:03 am
content: Thanks for the teardown. Interesting that they use a custom made resistor. My azonix uses a vishay foil(non hermetic)

author: dietert1
author_rank: Super Contributor
timestamp: September 16, 2020, 02:28:02 pm
content: How did you find out? We have some Arroyo TecSource controllers that also have a 24 bit ADC (ADS1256) but i could not tell yet which resistor i should upgrade. All SMD 0805 - about 100 of them.Here is a test log i got recently. I used 2x 10 KOhm thermistors, one for the Arroyo TecPak, one for a HP3456A resistance measurement. The TecPak is setup for 22 °C with Autotune and it is cooling since ambient temperature is above that, maybe 27 °C. Vertical scale is 1 Ohm which corresponds to 2 mK.The HP 3456A measurement exhibits an equivalent temperature noise of 0.033 mK on a 5 minute time scale. Its resolution is 10 mOhm, equivalent to 0.02 mK, So there is very little extra noise. But when looking at a log of several hours the ambient temperature process adds some mK. Resistance is going up during night when ambient is cooling down. That drift probably stems from the TecSource reference resistor and/or from imperfect thermal coupling between the two thermistors. Maybe i have to find and upgrade the reference resistor.Regards, Dieter
Bird Electronics SA-1700EX Site Analyzer Calibration - Page 1
Forum section: electronics / general

author: Roy D. Mercer
author_rank: Contributor
timestamp: September 16, 2020, 12:09:46 am
content: Does anyone know how Bird’s site analyzers are factory calibrated? They want $400 for a factory calibration. I replaced the on board coin cell. While I had it apart I saw no clues as to how it’s designed to be calibrated or put into a calibration mode. One thing I am not sure about is if I perform an OSL calibration with a load that has an average return loss of -42 dB, the Bird sets the reference to -60 dB.. Does anyone know if this is normal? When I perform an OSL calibration with a load much closer to -60 dB, the unit seems to be pretty accurate but It sure would be nice to know how the factory calibration is done.

author: Magnificent Bastard
author_rank: Regular Contributor
timestamp: September 16, 2020, 03:40:34 am
content: Quote from: Roy D. Mercer on September 16, 2020, 12:09:46 amAsk the factory if you can purchase a user/service/calibration manual (set). Tell them you will post the results on an international engineering BBS that has over 150000 users-- AND WE ENGINEERS ALL TALK TO EACH OTHER.
New addition to my frequency family!  5065A :^} - Page 1
Forum section: electronics / general

author: notfaded1
author_rank: Frequent Contributor
timestamp: September 13, 2020, 06:06:52 pm
content: Totally psyched I've added a new reference to my frequency family in my lab at home! I've always wanted one of these.I'm going to let it settle for a while before doing some comparisons against the 5071A. It has the 10811 10MHz upgrade in it.Thank you for making this happen!!!Bill

author: rubidium
author_rank: Regular Contributor
timestamp: September 15, 2020, 02:48:28 pm
content: That unit looks really clean. One hell of a score!I've been on the hunt for a 5065A for a couple of years but no joy.!Jim

author: NivagSwerdna
author_rank: Super Contributor
timestamp: September 15, 2020, 03:42:55 pm
content: Quote from: notfaded1 on September 13, 2020, 06:06:52 pmHard to imagine living without one.
SR1 standard resistor parts - Page 1
Forum section: electronics / general

author: jchw4
author_rank: Regular Contributor
timestamp: September 07, 2020, 07:08:10 pm
content: Just bought SR1 with shattered plastic nuts and worn out plugs.What could be a replacement for the plugs and nuts?I found that pomona 3276 could fit but haven't tried it yet.What are the options for the nuts? Did anybody try to buy parts from ESI?

author: Magnificent Bastard
author_rank: Regular Contributor
timestamp: September 07, 2020, 07:44:11 pm
content: Quote from: jchw4 on September 07, 2020, 07:08:10 pmIET Labs now owns the SR1 line of resistors. You could try them, but I doubt they would have the parts. If they DO have the part you need, it is almost made out of unobtainium, so expect a very high price. If they don't, you are looking at having to make any needed parts yourself.http://www.ietlabs.com

author: HighVoltage
author_rank: Super Contributor
timestamp: September 07, 2020, 08:05:02 pm
content: Most likely you will not get these parts unless you find another donor unit.I would make these parts on a lathe myself.

author: jchw4
author_rank: Regular Contributor
timestamp: September 08, 2020, 11:18:08 am
content: Quote from: Magnificent Bastard on September 07, 2020, 07:44:11 pmYou're right it's IET now. But SR1 is still listed as active, and:QuoteSo I guess they still have the parts.The question is actually whether anybody has an experience of getting something from them.Quote from: HighVoltage on September 07, 2020, 08:05:02 pmI did not think of it, but it sounds nice. Thank you!Unfortunately the nearby hackerspace with lathe and people whom I could ask for help is closed because of the COVID for the forseeble future. But I'll keep this in mind.

author: dacman
author_rank: Frequent Contributor
timestamp: September 08, 2020, 11:42:25 pm
content: The SR1 IET sells is of a different design. They do not sell the plastic nut for the ESI SR1.

author: binary01
author_rank: Contributor
timestamp: September 09, 2020, 12:04:56 pm
content: Quote from: jchw4 on September 08, 2020, 11:18:08 amI can't give any advice on your issue directly, but I recently purchased a resistance standard from IET and found them responsive and easy to deal with. I'm sure they'll respond about part availability if you ask.
New Oscilloquartz 8600-B unboxing - Page 1
Forum section: electronics / general

author: notfaded1
author_rank: Frequent Contributor
timestamp: September 27, 2020, 08:13:31 pm
content: Some unboxing pics of a new oscillator I acquired. I'm not so sure about the connector that came with it? I think I may want to redo the connector? What do you think?Bill

author: notfaded1
author_rank: Frequent Contributor
timestamp: September 27, 2020, 08:42:31 pm
content: I'd like to capture the warm up stats over GPIB but there's a lot variables... still thinking that through since I probably won't turn it off very often.Bill

author: notfaded1
author_rank: Frequent Contributor
timestamp: September 28, 2020, 04:39:27 pm
content: Would you really wire it this way as in the connector pics? It looks like the grounds are connected together... ok I could see that. Then it looks like 4, 5 and 9 may be all connected together. This would be just tying the two pot connections CW, CCW, and VC Input together. I'm going to tone those pins out on the connector so I can see for sure because this is how the BVA was wired up before.Thanks,Bill
CMU 200 basic informations - Page 1
Forum section: electronics / general

author: jean françois
author_rank: Contributor
timestamp: September 05, 2020, 09:49:11 am
content: Good morning all,delighted to come to this great blogg, I read everything about the CMU200. I am in the process of purchasing a CMU200, the goal being analog maintenance. given the complexity of this device, I would have need to clarify some points for the moment not knowing this device.The sale comes from the death of a friend, for me it is very important.But there is no one to inform me.there is no audio option B41, but does that mean that there is no audio signal available (two tone measurements) on the front panel and no audio measurements possible?is this option easily found? at an affordable price? is it easy to install?in basic version: is the RF4 50w input an option? or only 2w original?in the basic version there is only one HF generator?is the TG easy to install?I can indicate the references of the device:CMU-K45 version 5.21 (1100.0008.02) intel celeron 256mb version V850020506.The options: B21V4, B52V14, B56V14, B, B68, B95.in advance thank you if someone can think of my request this device is fabulous and the 3ghz spectrum is for me more certain.thank youAlain Markil.Bonjour

author: Grandchuck
author_rank: Super Contributor
timestamp: September 05, 2020, 12:12:31 pm
content: Hello Alain. You might get a better response in the Rf, Microwave, Ham Radio section.

author: jean françois
author_rank: Contributor
timestamp: September 05, 2020, 01:16:29 pm
content: hello thank you for your suggestion, .But it is however in the metrology section that I learned the most things about the CMU200,alain J F

author: richnormand
author_rank: Unknown
timestamp: September 05, 2020, 06:19:46 pm
content: i would suggest you also have a look at "repair" and "test equipment" in addition to a search for "cmu200" on the whole forum.There is a lot of information in this forum for the cmu200 and the crtu from many contributors but they are distributed on the needs of each situation.Cheers.
HP Agilent Keysight High/Low Current Triaxial Cables, How to Tell Them Apart - Page 1
Forum section: electronics / general

author: garrettm
author_rank: Frequent Contributor
timestamp: September 03, 2020, 08:37:36 am
content: So I just picked up a gaggle of HP/Agilent 3-lug triaxial cables recently and I noticed that one of the cables is slightly thicker than the others. The thicker one measures 5.3mm in diameter and the tinner ones are 4.9mm. When looking closely at the thinner cable, you can make out a crosshatch texture on the outer jacket, while the thicker cable is smooth.Reading over an Agilent accessories catalog, I can see two different part numbers: "16494A triaxial cable" and "16493L high current triaxial cable". The 16494A is rated up to 1A and sub-fA level measurements while the 16493L is rated for up to 4.2A and sub-pA measurements. The 16493L is only offered in 1.5 or 3 meter lengths. Meanwhile, the 16494A is offered in 0.4, 0.8, 1.5, 3 and 4 meter lengths.I have four cables in total: three 1.5m cables and a single 3m cable.The 3m cable matches two of the 1.5 meter cables in thickness, all thin with crosshatch pattern on jacket.So on to my questions:1) Would I be correct in assuming these thinner cables are all 16494A parts?2) Is the thicker cable with smooth jacket a high current 16493L? Or did HP/Agilent make different versions of the low current 16494A cable? (See question 4.)3) How would one tell the two models apart?4) Finally, did HP/Agilent even make these cables, or was it YHP/Yokogawa that made them? Just curious really, I saw a cable of very similar make to these for the 4140B that was printed with Yokogawa.Hewlett.Packard. It uses the thicker, smooth cable with a different triaxial connector:https://www.ebay.com/itm/Agilent-Hewlett-Packard-P-04061-61600-Bias-Lead-cable-4140A-Va-Vb-3-ft-1m-Coax/293322407157?hash=item444b60bcf5:g:uhUAAOSwqwRdx2WB

author: garrettm
author_rank: Frequent Contributor
timestamp: September 03, 2020, 12:02:29 pm
content: Hoo boy! After looking through the HP 4142B manual, it seems HP and Agilent part numbering systems for triaxial cables diverged.From what I can tell, the relevant part numbers would be 16493C (1A max) and 16493H (> 1.6A, the HP4142B manual doesn't state the cable's max).I'll measure the resistance of the cables later today. Hopefully that will help me figure out what the hell is going on with all these part numbers.It's pretty strange that both HP and Agilent didn't think to print the part numbers on the cables...They've done that with nearly every other type of cable I have from them.
FYI: Calbration of High Voltage Divider - Page 1
Forum section: electronics / general

author: intabits
author_rank: Frequent Contributor
timestamp: August 29, 2020, 07:19:15 pm
content: FYI...Apparently resistors change value with applied voltage over 1000v (new to me, I think).This document describes a method of determining the divider ratio with an accuracy to 0.001%. (Presumably only for DC, and only at a specific test voltage)From:-https://ntrs.nasa.gov/citations/19660000495

author: TimFox
author_rank: Super Contributor
timestamp: August 29, 2020, 10:14:06 pm
content: Ohm’s Law is a useful approximation in many circumstances, but it is not a fundamental law of physics. Wire wound resistors are probably the closest to “ohmic”, very short thick-film surface-mount resistors (not used in good high voltage dividers) can be bad, even at only 10 V. At the physical level, it depends on the linear voltage gradient (V per meter) along the path (very long in a wire wound part). In grad school, a lab down the floor had a huge unit, good for 100 kV, made from Julie Research wire wound resistors individually guarded, which was maybe 2 m by 2 m footprint and 2.5 m tall.
HP 3458A with error 202, worth a try? - Page 1
Forum section: electronics / general

author: dl1640
author_rank: Regular Contributor
timestamp: August 27, 2020, 04:17:00 pm
content: A local seller is offering a HP 3458A with error 202 for about 1700-USD, the serial number looks old and self test fails, I suppose it does not give a reading, I was told the only observed error is 202. I know this is fascinating gear for hobbyist but have no idea error 202 would be a easy fix?Input is welcomed.

author: notfaded1
author_rank: Frequent Contributor
timestamp: August 27, 2020, 04:29:03 pm
content: It looks like TiN ran into something like this before see here:https://xdevs.com/fix/hp3458a/This is just a thought... it may not be this see link above to read more.Bill202,“HARDWARE FAILURE — SLAVE TEST: CONVERGENCE”Repair for HARDWARE FAILURE — SLAVE TEST: CONVERGENCEIssue was simply in missing jumper on A1 DC Board, which selects voltage reference input for rest of circuitry.Image 149: Proper A1 PCBA jumper installation for normal operationAfter installation jumper on position NORMAL, as marked in green on photo above – this error is gone, as well as meter’s function on DCV,Ohms,ACV,frequency,period were recovered!

author: maat
author_rank: Regular Contributor
timestamp: August 27, 2020, 04:54:33 pm
content: Mine required a new A3 board. At least, that's what KS replaced, after it died with a 114,"SYSTEM ERROR -- balanced rundown convergence" error. Then after selftest, it gave me a 202,"HARDWARE FAILURE -- "SLAVE TEST: CONVERGENCE" . Your milage may vary.Edit: Oops. Fixed the board number KS replaced. I meant A3 not A9.

author: dl1640
author_rank: Regular Contributor
timestamp: August 28, 2020, 07:47:19 am
content: It seems too risky to have this unit for the price offered when I'm looking at service note.

author: martinr33
author_rank: Frequent Contributor
timestamp: August 29, 2020, 03:58:08 am
content: That's not a bad price. I picked up a unit with a convergence error that just required an autocal, just as lucky as the jumper. Problem is, with A3s no longer available, the only way out if it is bad is a $2700 Keysight repair and refresh. As the unit is local, maybe you can take a look.
HP 53305A Phase Measurement Software - Page 1
Forum section: electronics / general

author: 0culus
author_rank: Super Contributor
timestamp: August 23, 2020, 10:18:40 pm
content: Is anyone familiar with getting this software to work with a more modern GPIB to USB interface such as the 82357A?I successfully got an ancient version of the Agilent IO Library to recognize my 82357A and I'm able to send commands to various instruments on the bus (including my 53310A MDA) using the VISA client. However, the 53305A software will not recognize it. I get an error about SICL and file not found. FWIW I got the software from K04BB, which is the only place I could find it.Thanks!

author: KE5FX
author_rank: Super Contributor
timestamp: August 23, 2020, 10:40:34 pm
content: You've seen this thread, I assume?https://www.eevblog.com/forum/metrology/hp-53305a-phase-analysis-software/That's about the only reference I've run across.

author: 0culus
author_rank: Super Contributor
timestamp: August 23, 2020, 11:22:29 pm
content: Oooo, I hadn't. Looks like the insight I needed might be in there...thanks!

author: 0culus
author_rank: Super Contributor
timestamp: August 23, 2020, 11:42:02 pm
content: I don't think I can get my particular GPIB adapter to work. It needs a newer version of the IO libraries.

author: 0culus
author_rank: Super Contributor
timestamp: August 24, 2020, 12:52:31 am
content: OK, I was able to make a small amount of progress by adding the dll in the other thread to the windows system directory. Now the 53305A software SICL error tells me the interface address is bad, which is an improvement over "file not found".Problem is, the interface address is exactly as configured in the IO library, and it is working over there so it exists somewhere...partying like it's 1999!!!
SyncServer S250 - Any one have experience remotely getting information from it? - Page 1
Forum section: electronics / general

author: John1
author_rank: Newbie
timestamp: August 20, 2020, 03:51:02 pm
content: I have a Mircosemi SyncServer S250 right now, and what I am trying to do is write some (java) code so that when the S250 generates a 1PPS signal, it sends my computer the time of this 1PPS pulse.Anyone have any experience with this? Or any ideas as what to do?Also, in general, how do you get the discrete pulse time report over an Ethernet connection?

author: bgugi
author_rank: Contributor
timestamp: August 21, 2020, 05:43:27 am
content: why not have the pc pull an ntp request, then backdate the pulse?

author: John1
author_rank: Newbie
timestamp: August 21, 2020, 04:42:05 pm
content: How do you backdate the pulse via an NTP request? Couldn't find any info in the user guide. I am getting the device on monday so don't have much experience using it.
Et tu, LTZ1000A ?  -  out of stock at digikey, mouser, arrow - Page 1
Forum section: electronics / general

author: openloop
author_rank: Regular Contributor
timestamp: August 25, 2020, 01:07:28 pm
content: I'm not desperate as Ian with his LM399As, but I'm wondering...When they reappear... Will it be a good time to buy if one wants freshly baked, not pre-screened ones?

author: tszaboo
author_rank: Super Contributor
timestamp: August 25, 2020, 04:05:51 pm
content: Quantity Ship Date Estimate1 8/29/2020Ship dates are approximate and subject to change.

author: exe
author_rank: Unknown
timestamp: August 25, 2020, 06:38:37 pm
content: End of the era?

author: niner_007
author_rank: Frequent Contributor
timestamp: August 26, 2020, 03:42:36 am
content: Quote from: NANDBlog on August 25, 2020, 04:05:51 pmThat’s only 4 days, not so bad, wait when it’s 6 months delay
Recommendations wanted for AC calibrator. - Page 1
Forum section: electronics / general

author: TheDefpom
author_rank: Frequent Contributor
timestamp: August 20, 2020, 05:47:40 am
content: I already own a Valhalla 2703 and a Fluke 5200A, which both have certain feature sets.What I am looking for is something that crosses over and basically does everything in one box, so capable of going up to 1000VAC with adjustable frequency from 10Hz up to at least 50KHz, ideally higher, and with that capability at the high voltage settings.My Fluke can do 1MHz, but only up to 110V, my Valhalla can do 1000V, but only up to 1KHz (it can do 100KHz up to 120V)I am just wanting feedback about anything else out there (which doesn't cost $3000+) that I do not know about, so I could maybe consider getting one and selling off my existing ones (I do have the Fluke for sale actually, NZ only).

author: maginnovision
author_rank: Super Contributor
timestamp: August 20, 2020, 05:52:31 am
content: Don't sell the 5200 and find a 5205? You have to have the space but I think it's your best bet for the price.

author: srb1954
author_rank: Super Contributor
timestamp: August 21, 2020, 12:24:57 am
content: I would also like a Fluke 5205 to go with my 5200A but these only seem to pop up occasionally on the US market.Like the TheDefpom I am also located in NZ and the cost of freight from the US for a hefty beast like the 5205 is a major deal killer.
UK (Wales and SW) GNSS based reference users, GNSS Jamming activity - Page 1
Forum section: electronics / general

author: jc101
author_rank: Frequent Contributor
timestamp: August 17, 2020, 02:50:13 pm
content: For info, this popped up via the UK CAA today...This first one has a radius of 62nm (71 miles or 115km) around the specified coordinates.QuoteAlso there is another one planned for 8 September, though a much smaller radius.Quote

author: tggzzz
author_rank: Super Contributor
timestamp: August 17, 2020, 03:05:01 pm
content: A few years ago there were many NOTAMs about jamming, often around Aberystwyth.I've also heard reports of airfields being displaced, e.g. nominally directly overhead, but practically visible off a wingtipEyeballs rule; instruments lie

author: jc101
author_rank: Frequent Contributor
timestamp: August 17, 2020, 03:13:14 pm
content: Well the NOTAM is there too...Quote...but the CAA alert e-mail is more readable.As a rotary pilot navigation is easy, just drop down and read the road signs

author: tggzzz
author_rank: Super Contributor
timestamp: August 17, 2020, 03:21:29 pm
content: Quote from: jc101 on August 17, 2020, 03:13:14 pmAs an ex-glider pilot, dropping down is the easy bit. Finding the next working Cu/ridge or buzzard is the tricky bit(If in a powered aircraft, add the difficulty of flying straight and level, and not falling asleep through boredom)
Reference clock time drift calculation - Page 1
Forum section: electronics / general

author: Harvs
author_rank: Super Contributor
timestamp: August 14, 2020, 03:56:14 am
content: I hoping someone might just be able to point me at a good app note or book.I'm trying to understand and calculate the time accuracy of various off the shelf GPS disciplined reference clocks upon loss of GPS for an industrial PTP application. Sometimes referred to as "holdup" in datasheets.What I want to be able to say is, with an accuracy requirement of say +/-1us to GPS time, how long can x clock operate with loss of GPS signal and any what-if's associated with it (e.g. temperature control.) Effectively I'm trying to convert the parameters given in the datasheets into an x time accuracy loss per hour.Any pointers?Thanks

author: awallin
author_rank: Frequent Contributor
timestamp: August 14, 2020, 05:07:05 am
content: https://www.meinbergglobal.com/english/specs/gpsopt.htmfor example in the first column they say the TCXO is +/-1e-7 (fractional frequency) over one day.Their holdover values seem to be calculated assuming half of that value:one-day-drift = 24*3600*5e-8 = 4.3 ms

author: Harvs
author_rank: Super Contributor
timestamp: August 14, 2020, 09:39:16 am
content: That's nice that they give some accuracy over time. However quite a few just give time and temperature dependence of the oscillator. Some others have external oscillator options where you can add an external rubidium reference.e.g. frequency ppb per day and year as well as temperature ppb per degreeIt would seem to me that if the drift in frequency is linear (which I have no real idea if it is or not over the 1 day time scale???) Then the drift in time won't be. Clearly as frequency gets further from the ideal, the rate of divergence in time will increase. I'm sure there's an equation for this I just haven't been able to find.

author: awallin
author_rank: Frequent Contributor
timestamp: August 14, 2020, 06:38:35 pm
content: from phase (time) you get to frequency by differentiation. so to go from frequency (e.g. linear drift) to phase you integrate.linear frequency drift gives parabolic phase-drift.see e.g. eqn. (30) herehttps://www.researchgate.net/publication/234966458_Introduction_to_Time_and_Frequency_Metrology

author: Harvs
author_rank: Super Contributor
timestamp: August 14, 2020, 10:49:13 pm
content: That paper looks like a great intro, thanks!
HP App note AN-19 or Service note 885A-1 TECHNIQUE FOR CALIBRATING PHASE Shifter - Page 1
Forum section: electronics / general

author: volvo_nut_v70
author_rank: Regular Contributor
timestamp: August 14, 2020, 07:25:32 pm
content: It's missing from here:http://hpmemoryproject.org/ressources/resrc_an_01.htm