hybridfree/eevblog-posts huggingface dataset:
LeCroy WaveJet 324A won't start - Page 1
Forum section: electronics / testgear

author: gaminn
author_rank: Frequent Contributor
timestamp: June 06, 2017, 08:55:58 am
content: Hi,when I turn on LeCroy WaveJet 324A, boot screen with LeCroy logo displays. Then display turns black and REF, AUTO, STOP/SINGLE and button "2" (channel 2) starts blinking and scope starts beeping.Can you please help me troubleshoot this?

author: HighVoltage
author_rank: Super Contributor
timestamp: June 06, 2017, 11:39:07 am
content: I don't have a LeCroy anymore but in the past I had one 324A and repaired it.In such a case always start with the power supply inside the scope and make sure all DC rails are good and clean of any oscillations.

author: gaminn
author_rank: Frequent Contributor
timestamp: June 06, 2017, 02:24:02 pm
content: Thanks. And do you know what the scope signals (blinking buttons and beeping)?

author: HighVoltage
author_rank: Super Contributor
timestamp: June 06, 2017, 02:44:09 pm
content: Quote from: gaminn on June 06, 2017, 02:24:02 pmNo, sorry, I do not know.When an instrument behaves strangely, a small hope is that the problem is related to a power supply issue. And in real life, I had plenty of instrument problems that were solved by just analyzing and fixing the PSU. Of course it can be something else but this is a good start.

author: jpb
author_rank: Super Contributor
timestamp: June 06, 2017, 02:57:24 pm
content: I have a 334 WaveJet but I can't really help you with this as there is nothing in my user manual.When I first bought the scope I looked at buying the repair/maintenance manual which was available in the US (I live in the UK) but it was going to cost me getting on £150 to £200 so I didn't get it.It might be worth you while getting a copy, try e-bay:TA used to sell it for $125 but it is now discontinued:http://www.tequipment.net/LeCroy/WJ300-SM-E/Manuals/Digikey still list it but with 0 available:https://www.digikey.com/product-detail/en/teledyne-lecroy/WJ300-SM-E/WJ300-SM-E-ND/4477717Those both are for the original 300 series (the one I have) there may be a new part number for the 300A series that you have.
Pictures of Fluke 789 and 28 II Ex - Page 1
Forum section: electronics / testgear

author: lypse
author_rank: Contributor
timestamp: June 05, 2017, 04:02:38 pm
content: Some Pictures of work toolsI dont like the fluke 28 II Ex much, only the selector switch is better and it requires less paperwork to use in hazardus areas..But it miss the nice features when working on 4-20mA signals that 789 have.

author: lypse
author_rank: Contributor
timestamp: June 05, 2017, 04:04:42 pm
content: There is more to see inside Fluke 789.
Hygrometer probe for multimeter - Page 1
Forum section: electronics / testgear

author: burnettm
author_rank: Newbie
timestamp: June 03, 2017, 07:35:06 am
content: Do hygrometer (relative humidity) probes which output millivolts in to banana plugs (similar to the Fluke 80TK thermocouple module) exist? If so, could anyone recommend anything affordable? I am interested in making cheese and need to monitor the humidity of the enclosure the cheese in aging in. I see cheap Chinese standalone units on Amazon which have min/max/avg functions, but if possible i'd like something which would just be a probe which I could plug in to my multimeter so I could monitor humidity without having to open the enclosure.

author: SeanB
author_rank: Super Contributor
timestamp: June 03, 2017, 07:54:28 am
content: Biggest problem with cheese making is the probes will have a very short life, as the acetic acid cheese gives off during maturation will kill them pretty fast. Best is to get the cheap sensors with I2c digital outputs, and use a microcontroller to simply read the data and display it on a cheap LCD display. Then you can just have a socket and plug in the spare sensors as they die. As a bonus you also get a temperature sensor on the board as well.

author: burnettm
author_rank: Newbie
timestamp: June 04, 2017, 02:23:42 am
content: I wasnt aware of acid problem, thanks for the info.

author: burnettm
author_rank: Newbie
timestamp: June 04, 2017, 02:26:49 am
content: I should have also asked if you have any direct experience with this, and if so what the approximate expected lifespan of the I2C hygrometers is and what their failure modes are like. Do they just die completely or do they start giving off inaccurate readings, and if the latter is there any way to easily test/calibrate them.

author: SeanB
author_rank: Super Contributor
timestamp: June 04, 2017, 07:44:20 am
content: They will get inaccurate then die with a reading that is off scale one way or the other, or with no output. Easiest way to test is to keep spares, and change them with one that is outside and next to a simple cheap all in one unit and compare readings, if they agree within 3C and 20% RH ( they really do have that unit to unit difference) then they still work, and then you can just put it back in service till it dies. Outer unit just has to be kept in a room with no drafts, and leave for around 3 hours to stabilise.

author: burnettm
author_rank: Newbie
timestamp: June 05, 2017, 06:07:57 am
content: Thanks for the info.
Tektronix TDS attenuator relays replacement - Page 1
Forum section: electronics / testgear

author: eKretz
author_rank: Frequent Contributor
timestamp: June 03, 2017, 04:36:46 am
content: After having multiple SPC failures on my Tek TDS754D I've taken it apart to replace the attenuator relays. It was also sickeningly filthy so I went ahead and washed all the boards then baked them dry. I've put everything back together now besides the acquisition board and am ready to work on the relays. I've disassembled the front end except for the ceramic boards - to get these out do I need to desolder the the connection to the BNC deep down in the housing? I don't want to mess these up so I thought it best to hopefully get the question answered by someone who has already done it. Anybody got a good source for the relays? Anybody have any success refreshing the old ones?

author: eKretz
author_rank: Frequent Contributor
timestamp: June 03, 2017, 07:36:30 am
content: Okeydoke, figured out how to get the boards out, on to replacing the relays.

author: capt bullshot
author_rank: Super Contributor
timestamp: June 03, 2017, 08:44:40 am
content: I once had just a bad solder joint on one of these relays. Re-soldering fixed this particular problem, no need to change the relay. I discovered the fault by testing the relays with a function gen set to 10Hz, and feeding this signal into the coil to recover worn out contacts. If you exercise the relay by rapidly switching on and off, the contacts get better (not always, and the effect doesn't last forever).So just check the solder joints before removing the relays, it might be unnecessary.

author: snoopy
author_rank: Frequent Contributor
timestamp: June 03, 2017, 11:51:58 am
content: Quote from: eKretz on June 03, 2017, 07:36:30 amI just cut the relay pins and unsoldered the remaining stubs and replaced the lot of them. Some had even gone open circuit !! Don't muck around. Just order 16 of them and replace them allcheers

author: eKretz
author_rank: Frequent Contributor
timestamp: June 03, 2017, 04:18:15 pm
content: I think I'll just replace them also. I got a very attractive price on this scope so it won't really hurt the bottom line. It was less than a Rigol 1054 by a fair bit.

author: eKretz
author_rank: Frequent Contributor
timestamp: June 04, 2017, 08:14:14 pm
content: I've done a 4-wire resistance check on the NC relay contacts I could reach, and some are within the 0.01 ohm to 0.02 ohm range but others are way high. I decided to swap in my attenuator assembly from my 754A which always passes SPC and it definitely cured the problem. I may just grab enough spare to do that board as well.
Cheap LCR - Page 1
Forum section: electronics / testgear

author: Coiljunkie
author_rank: Contributor
timestamp: June 06, 2017, 01:36:15 am
content: Are any of these cheap handheld lcr meters on ebay half way accurate? Or are they a complete waste of time. I'm a beginner so I don't need or even deserve a 500.00+ lcr meter. Just something that will make sure I don't blow my chips.http://www.ebay.com.au/itm/HoldPeak-HP-4070L-Digital-Capacitance-Meter-Inductance-Meter-LCR-Meter-/201921415260?hash=item2f0374485c:g:bfYAAOSw5cNYZhDMhttp://www.ebay.com.au/itm/Portable-MK328-12864-LCD-Transistor-Tester-Diode-Capacitance-LCR-ESR-Meter-TE703-/172588577467?hash=item282f14b2bb:g:5NwAAOSw4A5Y0m3Jhttp://www.ebay.com.au/itm/New-Transistor-Tester-128-160-TFT-Color-Diode-Thyristor-MOSFET-ESR-LCR-Meter-/222274207605?hash=item33c0933f75:g:l1QAAOSwcLxYGWNGThanks in advance.

author: tigr
author_rank: Regular Contributor
timestamp: June 06, 2017, 06:38:37 am
content: HP4070.Small range of capacitance measurement.It does not measure ESR,which is very important.

author: ebclr
author_rank: Super Contributor
timestamp: June 06, 2017, 07:02:42 am
content: This one is quite goodhttps://wholesaler.alibaba.com/product-detail/New-Lcr-T3-Graphic-Transistor-Electronic_60513738679.html?spm=a2700.7724838.0.0.sLfbjn

author: Coiljunkie
author_rank: Contributor
timestamp: June 06, 2017, 07:46:42 am
content: it looks very good but I wouldn't be able to appreciate it and I don't want to spend that kind of money until I know a bit more. Thanks for the suggestion.

author: coromonadalix
author_rank: Super Contributor
timestamp: June 06, 2017, 09:59:47 am
content: go for a DE-5000 they dont cost a fortune and will work well for most jobsall the other made with avr pics can be good, it depends on the firmware quality and checks, i have one m328, it is a surprising gizmo, i made the externals reference mods to have better quality and stabilitythere's a thread here about thes modelsBut for a beginner, go for a hassle free model like de-5000, mastech ms5308 (is higher priced for nothing) they have the same chips inside ...
TTI (Thurlby Thandar) PL154 PSU Service Manual - Page 1
Forum section: electronics / testgear

author: linker3000
author_rank: Contributor
timestamp: June 03, 2017, 11:16:38 am
content: Does anyone have a service manual for this bench PSU. I understand there may be MKx variants - This is mine testing a bubble display (whoa - big pic!):Thanks

author: Andy Watson
author_rank: Super Contributor
timestamp: June 03, 2017, 12:19:26 pm
content: Third time lucky ? Previous attempts have returned "Your file is too large." I have a copy of the later version but it is 1.9MB.P.S. Later version available here:http://www.ko4bb.com/getsimple/index.php?id=manuals&dir=06_Misc_Test_Equipment/Thurlby_TTi

author: linker3000
author_rank: Contributor
timestamp: June 03, 2017, 01:21:10 pm
content: Excellent - many thanks. Forgot to manually check out ko4bb, and general Web searches were not finding the manual as it's listed as 'pl-series...'
Rohde HMC8043 load regulation - Page 1
Forum section: electronics / testgear

author: grouchobyte
author_rank: Regular Contributor
timestamp: June 02, 2017, 02:28:19 pm
content: I recently picked up a RS HMC 8043 power supply as a complement to my aAgilent linear supplies and another Rohde HMP2030. I need lots of power supplies when doing my metrology consulting projects.I am aware that switching supplies with linear post regulation like the 8403 are a little noisy at light loads, however this supply is marginal in that regard. I powered a cooling muffin fan with one channel 12 v @ 140 mA and the readback voltage was jumping a by +\- 5 mV on the display. I confirmed this with a scope.Apparently that is specd and within the acceptable range.I just wish it would do a better job or transient load regulation and do a little averaging on the display readout so it is not jumping around so much.Comments?@grouchobyte

author: Messtechniker
author_rank: Frequent Contributor
timestamp: June 02, 2017, 05:49:52 pm
content: Quote from: grouchobyte on June 02, 2017, 02:28:19 pmBack EMF from the fan?

author: grouchobyte
author_rank: Regular Contributor
timestamp: June 02, 2017, 08:43:02 pm
content: Quote from: Messtechniker on June 02, 2017, 05:49:52 pmProbably back EMF like you suggest. However I would expect the current to change with a variable load like a bad fan bearing and the current does go up and down as one would expect. In constant voltage mode it does a less than ideal job of maintaining constant voltage in light of the linear post regulation and its ability to regulate under transient load conditions. Even a large cap on the output fails to keep the voltage stable, although not a great idea if you want current limiting under transient load conditions.@grouchobyte

author: Kleinstein
author_rank: Super Contributor
timestamp: June 03, 2017, 07:41:43 am
content: Some fans have quite some jumps in the current consumptions. This is not so much back EMF, but more like PWM like switching of a brush-less motor. If they save a penny on fast diodes this can include spikes from reverse recovery. At least you can expect the current to go down to nearly 0 (e.g. 1 mA for the control circuit) at some times. Some fans also have extra capacitance to ease on the variable current - but an additional low ESR capacitance may have a negative effect on load regulation. If the fan includes speed regulation, it may even have an effective negative load impedance as it would need more current at lower voltage. A good supply should still be stable, as the input side of switched mode regulators can behave similar.So the fan is actually a difficult load to a power supply and thus a good test. However the interesting part would be looking at the output with a scope.
[Very] Cheap USB multimeter or USB oscilloscope? - Page 1
Forum section: electronics / testgear

author: kalel
author_rank: Frequent Contributor
timestamp: June 02, 2017, 10:20:38 pm
content: Hi there,The very low (bottom) range is probably not of much interest to most experienced people, but might be interesting to beginners with less knowledge and budget to invest (used market aside, some people can score really great deals used, but those vary by country and specific date).With USB oscilloscopes going down to about $50-60 from China with shipping, and no idea about how much their USB multimeters are going for, assuming you can't get both, which of those two items would you find more useful for a true beginner?Is a USB multimeter slightly cheaper to construct than an oscilloscope, and could that mean a potential better quality of usb multimeters vs oscilloscopes for a similar cheap price?On the other hand, would a USB oscilloscope offer most of the functionality of a USB multimeter?Maybe another way to ask would be if you had to choose one of these two item types, which would you choose.Edit: This might be a wrong way to ask since as not being a beginner, you might have different specific needs and low end gear could simply lack the functionality you need altogether.

author: kalel
author_rank: Frequent Contributor
timestamp: June 02, 2017, 10:41:09 pm
content: Thanks. Well I assume the bottom line products of either category aren't perfect performers, I'm just trying to determine if there are any reasons why one of the two types might be of better quality for a similar price (e.g. needs less expensive hardware, can work with cheaper parts, etc)Which item type would be more useful to a beginner is probably as important as well, but you can get handheld multimeters (non-usb) very cheaply, and you can't get oscilloscopes for that price. Actually, there are those $16 DSO kits, but they seem to be much more limited than the $50 USB units.
Question about Agilent E3631 PSU step resolution - Page 1
Forum section: electronics / testgear

author: nour
author_rank: Frequent Contributor
timestamp: June 01, 2017, 10:18:59 am
content: I am interested in buying used E3631(haven't yet decided) and I was reading the specs.Programming Accuracy at 25°C ±5°CVoltage: 0.05% + 20 mV, 0.05% + 20 mV, 0.1% + 5 mV+Current: 0.15% + 4 mA, 0.15% + 4 mA, 0.2% + 10 mAI want to confirm the meaning of the last couple of lines, regarding the step resolution does it means I can step voltage 20mV for every step and 4mA for the current?

author: coromonadalix
author_rank: Super Contributor
timestamp: June 01, 2017, 10:59:24 am
content: Please don't double post

author: HighVoltage
author_rank: Super Contributor
timestamp: June 01, 2017, 11:11:24 am
content: Quote from: nour on June 01, 2017, 10:18:59 amNo!In the 6V output setting you can step by 1 mV and 1 mA per stepIn the 25 V output setting you can step 10 mV and 1 mA per step

author: nour
author_rank: Frequent Contributor
timestamp: June 01, 2017, 11:32:46 am
content: Quote from: HighVoltage on June 01, 2017, 11:11:24 amI am sorry, which part of the specs. are saying 1mV?, I didn't get it!thanks

author: HighVoltage
author_rank: Super Contributor
timestamp: June 01, 2017, 02:34:01 pm
content: For the E3631A, you can adjust the output voltage in 1 mV steps in the 6V output range.This can be done manually by the front panel or automatically through remote control.I have a really nice Agilent E3631A for sale.Let me know, if you are interested.This is still a current model and the new list price in Germany is Euro 1500
Keysight Service Note, specification change for the  3446xA/34470A Series DMMs - Page 1
Forum section: electronics / testgear

author: JimmyJo
author_rank: Contributor
timestamp: June 05, 2017, 01:48:46 pm
content: http://literature.cdn.keysight.com/litweb/pdf/34461A-04.pdfI regularly use my 61 and 65 to measure these voltages, how screwed am I?

author: gslick
author_rank: Frequent Contributor
timestamp: June 05, 2017, 02:10:23 pm
content: Already a long thread about this:https://www.eevblog.com/forum/testgear/keysight-34460a34461a34465a34470a-maximum-allowable-voltage-change-notice/

author: boggis the cat
author_rank: Regular Contributor
timestamp: June 07, 2017, 04:18:30 am
content: Simple answer: there was never an actual problem.If your instrument has "600 Vdc / 440 Vac" labels on the front and back, you should peel them off.(Seehttps://servicenotes.literature.keysight.com/litapp/SearchSN.do?method=openExternalSNSearch&prodNum=34461A, Service Note No 34461A-04A.)
Dealer for Brymen 257s in the US, or alternative? - Page 1
Forum section: electronics / testgear

author: Peter_G
author_rank: Newbie
timestamp: June 01, 2017, 06:34:39 pm
content: I am looking to buy a multimeter for my school robotics team. I personally have a Brymen 257s which would suit our purposes fine, but the only place I can find one is TME which is outside the US and my school can't order from overseas. I can't find the Brymen 257s anywhere else besides Amazon and ebay which are also off limits.Does anyone know of somewhere in the US I can get the Brymen 257s, or a similarly speced and priced quality one?

author: Wytnucls
author_rank: Super Contributor
timestamp: June 01, 2017, 07:34:36 pm
content: Greenlee 510Ahttps://www.amazon.com/Greenlee-DM-510A-Professional-Digital-Multimeter/dp/B003TO5YU0http://www.greenlee.com/products/DMM%2540cTRMS%2540cAC%2540FDC%2540cCAP%2540cTEMP(DM%2540d510A).html?product_id=17752
hacking MSO1000Z with USB blaster - Page 1
Forum section: electronics / testgear

author: Gioreva
author_rank: Contributor
timestamp: June 01, 2017, 07:10:55 am
content: HiI used china USB blaster.10 hours for download.Driver of USB blaster is WinUSBC:\openocd-0.10.0\bin-x64\openocd.exe -d1 -f C:\openocd-0.10.0\scripts\interface\altera-usb-blaster.cfg -f C:\openocd-0.10.0\scripts\target\imx28.cfgtelnet a 127.0.0.1 : 4444haltdump_image rigol.bin 0x40000000 0x3FFFFFFrigup scan rigol.bin > mso1074zs.txtrigup license mso1074z.txt 0x1C0FFOn rigol:Utility>Options>Setup>Editor=ONif halt do not respond message, remove JTAG and re connect.
Siglent SDS 1202X-E cursor measurement - Page 1
Forum section: electronics / testgear

author: Skyhein
author_rank: Newbie
timestamp: May 30, 2017, 09:28:53 pm
content: Hi,if I measure a voltage with cursors (on my Siglent SDS 1202X-E) the 10X probe attenuation won't be respected by cursor measurement. As you can see in the image below, the voltage is about 5 volts, and the cursor measurement window shows about one tenth of it, whereas counting the divisions or looking at the amplitude shows the 5 volts.Is it a problem of the oscilloscope or is it me not understanding?Greetings

author: tautech
author_rank: Super Contributor
timestamp: May 30, 2017, 10:04:48 pm
content: It's a bug.I'll chase up when the FW update is expected and update when I have some answer.

author: klaff
author_rank: Regular Contributor
timestamp: May 31, 2017, 08:09:52 pm
content: Hi Tautech, Is there a place one should post about apparent bugs? Or should we create a thread solely for that purpose?

author: tautech
author_rank: Super Contributor
timestamp: May 31, 2017, 08:42:34 pm
content: Quote from: klaff on May 31, 2017, 08:09:52 pmHere's OK or in the Siglent support thread.https://www.eevblog.com/forum/testgear/siglent-technical-support-join-in-eevblog/From inquiry yesterday there will be new FW sometime in June.
EEVblog BM235 Multimeter - MAX/MIN/AVG Record mode - Page 1
Forum section: electronics / testgear

author: tangram
author_rank: Contributor
timestamp: December 08, 2016, 05:38:22 pm
content: I've done the decent thing and searched, but can't find anything on this topic related to my query on the forum, which is:Clearly I need to be testing this with an oscilloscope, but I don't have one at the moment (DS1054Z in my wish list!). I'm looking at start-up spikes when switching on a PSU and I'm wondering if the MAX/MIN/AVG Record mode on the EEVblog BM235 Multimeter will be fast enough to catch any that are created?I'm not expecting a high degree of accuracy for this. Clearly a multimeter, even one as epic and awesome as the EEVblog BM235 meter is the wrong tool for the job, but how fast is the BM235? How long will a voltage change need to be in-circuit for the meter to read it and record it?

author: MosherIV
author_rank: Super Contributor
timestamp: December 09, 2016, 12:41:00 pm
content: QuoteNope, affraid not. Generally (and someone will correct me I am sure) DMMs sample and hold the volt to be measured. The sample rate depends on the meter but I would guess most meters with the 'bar graph' feature are sampling at least 40 times a second.It would be pure chance if the meter catches the start-up spike.

author: EEVblog
author_rank: Unknown
timestamp: December 09, 2016, 01:18:31 pm
content: Quote from: MosherIV on December 09, 2016, 12:41:00 pmAt a reduced resolution. Multimeter chipsets have two ADC's - the full res one for normal measurements, circa 5/sec, and a lower res one for the bargraph.Min/Max would use the full res one.

author: tangram
author_rank: Contributor
timestamp: May 31, 2017, 12:27:21 pm
content: Thanks for the feedback guys. Having experimented, I came to the conclusion that coincides with your excellent advice, and I subsequently bought a DS1054Z.Incidentally, the purchase of the 'scope lead me to buying a DP832 as the power spikes revealed on the piece of chinese junk I was testing were bloody horrendous!
Tek 2465B Calibration Help..! - Page 1
Forum section: electronics / testgear

author: Isobaricau
author_rank: Newbie
timestamp: May 31, 2017, 08:39:16 am
content: Yeah I know first post and already asking for help! My apologies!I've read the epic "2465b Tear Down" thread after scoring a my own 2465b and have to say that I've gained a wealth of knowledge thanks to thecontributors. I congratulate you all for taking the time to share ideas and experiences, what a great forum this is.I've embarked on rejuvenating my scope despite the fact it's had little use If I'm led to believe the 450 hours use stored in memory?I started with replacing all the usual suspect caps in the power supply, A5 and A1 boards along with the DS1225Y change to an FM16W08.It's clearly out of cal despite the successful copy of memory from DS1225Y over to FM16W08.My issue is that I although I managed to perform Cal 02 (Vertical Cal) I'm stuck when it comes to the Horizontal Cal as my Siglent Arb function gen. maxes out at 40nsand according to the procedure I need to get down to 2ns.So this is call to anyone who can assist or point me in the direction of a Time Mark Gen. or Pulse Gen. in my geographic location.I'd happily hire the gear or pay someone who has the right equipment!I'm so close to getting this finished after a long but enjoyable process and will share some pics when done.A big thanks in advance to anyone who can assist.I'm in Melbourne, Australia.
hantek DSO4102C  - Has anybody tried to run it with Openhantek - Page 1
Forum section: electronics / testgear

author: ErwinB
author_rank: Newbie
timestamp: May 31, 2017, 07:50:57 am
content: Hello,I recently bought a Hantek DSO4102C, but since I run only Linux I cannot use the software that is bundled with it. I went out to look for alternatives and found Openhantek (https://github.com/OpenHantek/openhantek). But that does seem to be lacking a bit in the documentation department. Is there anybody here that has some knowledge of this software and has tried or knows of someone who has tried to run it with this scope?thanks, Erwin.
Rigol DG-1022Z function gen. Can FM frequency track main frequency? - Page 1
Forum section: electronics / testgear

author: Circlotron
author_rank: Super Contributor
timestamp: May 29, 2017, 12:02:01 pm
content: Looking at possibly getting Rigol DG-1022Z function generator. One thing I want to do with it is generate a 100Hz square wave and frequency modulate it at 12.5Hz from the second channel. Then when I wind the 100Hz frequency up and down a bit can I have it so the modulation frequency from channel 2 tracks channel 1 in a ratiometric manner. That is to say, if I increase channel 1 frequency from 100Hz to 150Hz can channel 2 automatically follow from 12.5Hz to 18.75Hz?The purpose of this is to simulate an optical encoder reading a slotted disc that is not perfectly central on a rotating shaft to see how well some software tolerates this imperfect signal.
Opening a PCE-IT55 Insulation Tester - Page 1
Forum section: electronics / testgear

author: Ochsenfrosch
author_rank: Newbie
timestamp: May 28, 2017, 05:58:21 pm
content: Comes for about 140,-€ in Germany

author: WackyGerman
author_rank: Regular Contributor
timestamp: May 28, 2017, 06:11:21 pm
content: The hand soldering is not the best quality but the rest doesn t look that bad

author: Hydrawerk
author_rank: Super Contributor
timestamp: May 28, 2017, 11:04:37 pm
content: Looks like made by CEM.http://www.cem-instruments.com/en/
Tektronix RSA607A Real-Time Spectrum Analyzer Review, Teardown & Experiments - Page 1
Forum section: electronics / testgear

author: Hugoneus
author_rank: Frequent Contributor
timestamp: May 28, 2017, 10:39:11 pm
content: In this episode Shahriar reviews the Tektronix RSA607A real-time spectrum analyzer which operates from 9kHz to 7.5GHz. The instrument has a 40MHz wide analysis window with a DANL of -160dBm. The built-in tracking generator is capable of measuring return loss, cable loss and DTF measurements without a need for an external coupler. This review is organized as follows:01:03 – Model comparison and overview.03:25 – Front & rear panel overview.05:31 – Complete unit teardown & examination.16:33 – Reverse engineering and experiments with a drone remote control transmitter.39:27 – Characterizing and experimenting with an ISM band diplexer.47:29 – Return loss measurements of a tunable band-pass filter.53:23 – Concluding remarks.You can watch it here: [55 Minutes]youtu.be/CFQxqZcWGHgThe Signal Pathwww.TheSignalPath.comwww.YouTube.com/TheSignalPathwww.Patreon.com/TheSignalPath

author: Hugoneus
author_rank: Frequent Contributor
timestamp: May 30, 2017, 02:41:44 am
content: Some new information:Advanced triggering is available on the dedicated instruments because local processing on the RF data is possible. For USB based instruments this function is not available. Zero-span is however something Tek is considering.

author: technogeeky
author_rank: Frequent Contributor
timestamp: May 30, 2017, 02:53:52 am
content: Quote from: Hugoneus on May 30, 2017, 02:41:44 amThanks for the videos as well. When Tek responds to such inquiries, can you also counter-respond (without shaming them or anything) if you think their assertion is reasonable?I understand that whatever "advanced triggering" is might not be possible, but surely they can allow you to trigger on a span less than the entire 40 MHz realtime analysis window. In a world where everyone and their pet kittens use frequency hopping, not being able to get a clean trigger on a single channel is hamstringing this instrument a little bit.I was also wondering why this instrument would be better than the previously reviewed RSA from Tektronix, until I saw the one-port measurement capability which I don't think the other RSA had.Pretty cool device. I agree with you too, that board is beautifully laid out.

author: w2aew
author_rank: Super Contributor
timestamp: May 30, 2017, 03:01:05 am
content: Quote from: technogeeky on May 30, 2017, 02:53:52 amIn addition to the tracking generator and slightly higher frequency range - this instrument is line powered (or the battery powered version), compared to the RSA306B which is powered off of the USB port. This limits the amount of RF performance due to the 4.5W of total power dissipation available. This unit therefore has better spurious performance, lower phase noise, and gives you manual control over things like the input attenuator and preamp.
Oscilloscope - Beckman 9202 20MHz - Should I buy it? - Page 1
Forum section: electronics / testgear

author: keilara
author_rank: Newbie
timestamp: May 28, 2017, 02:55:59 pm
content: I found a Beckman 9202 20MHz oscilloscope for $30. Is it any good? I couldn't find much about it or any manual... Does anyone have the same oscilloscope and/or the manual for it?

author: tautech
author_rank: Super Contributor
timestamp: May 28, 2017, 07:01:50 pm
content: Welcome to the forum.From a quick Google search there is mention that it's a rebranded Hang Chung:https://www.electronicspoint.com/threads/beckman-9202-scope-manual.280523/So another search finds:https://elektrotanya.com/hung_chang_hc5602_oscilloscope_sm.pdf/download.htmlIt's a big manual, 26.4 Mb.Wait for 'Processing to change to 'Get Manual'.If it looks the same, $30 is a good price for a working scope, grab it.

author: keilara
author_rank: Newbie
timestamp: May 28, 2017, 07:56:54 pm
content: Thanks, I'm glad to be here.Yeah, it looks just like the manual you found. Thanks for finding itFrom what I can tell from the seller's pictures, he's taken well care of it. I'll buy it before someone else does it.
Basic question: segmented memory and serial decode (RTB2004 or others) - Page 1
Forum section: electronics / testgear

author: LaurentR
author_rank: Frequent Contributor
timestamp: May 28, 2017, 04:16:01 pm
content: Hi all,I have been trying to reverse engineer the content and timing of a serial comm link (UART, 115kbauds) and some associated signals with the RTB2004.I am new to segmented memory. I have successfully programmed it to use multiple segments, trigger on serial signal falling edge and see most of the traffic in the history buffer.The issue I have is that while the traffic has very long pauses, making it a good target for segmented memory, sometimes, there is a long, continuous exchange, so no matter what window size I use, either I have a lot of small segments, but spill over on occasion, or a few large segments and I run out of segments.When using a short segment size, the end of the segment cuts off whatever is going on and the new triggers starts later, mangling at least a byte of decode, often more due to the inter-segment blanking.Is there a way on the RTB or other segmented memory scope to "chain" segments when there is still traffic going on? (e.g. the trigger still triggering toward the end of the current segment) so that no traffic is lost? At 115kbauds, the waveforms/sec should not really be an issue (although I understand _some_ blanking, however short, may still be needed).I have to say that searching through the RTB history buffer with a mouse on the PC is really nice and quick and this lost of information has been my only issue. I can see how this could be a built-in limitation of segmented memory.At the same time, the USB LAs like Saleae have no issue with this as they have gapless memory as long as the PC has space.
Tek TDS7104 odd symbols being displayed, how to fix? - Page 1
Forum section: electronics / testgear

author: Jwalling
author_rank: Unknown
timestamp: May 27, 2017, 07:04:32 pm
content: This TDS7104 displays an odd symbol (Alpha? with a little dot to the upper left) instead of the Omega symbol when in 50Ohm mode. Also shows what looks like a British pound symbol where the trigger slope symbol should be instead of a rising edge symbol; if I set it to falling edge, it displays the fraction 1/2. I suspect that this is a Windows thing (scope is running Windows XP), but I'm not sure. The only thing I'm sure of is that this is really annoying...In the control panel, I've checked that the regional and language options are set to English (United States) so it's not there.Anyone know how to fix this?Thanks.

author: TheSteve
author_rank: Unknown
timestamp: May 27, 2017, 08:25:07 pm
content: You need to install the Tek specific font packs. It has been previously detailed in a thread here and I've attached the needed fonts.

author: Jwalling
author_rank: Unknown
timestamp: May 27, 2017, 09:11:16 pm
content: Quote from: TheSteve on May 27, 2017, 08:25:07 pmHi Steve, did you forget to attach them?Edit: maybe this.https://xdevs.com/doc/Tektronix/TDS7000/tekfonts.zipWill give those a try.

author: TheSteve
author_rank: Unknown
timestamp: May 27, 2017, 10:43:50 pm
content: Sorry, I meant I had attached them previously. They are in the master TDS7xxx thread:https://www.eevblog.com/forum/testgear/tek-csa7404-repair-project/msg896911/#msg896911

author: Jwalling
author_rank: Unknown
timestamp: May 28, 2017, 11:16:56 am
content: Thanks Steve, that did the trick. Weird that they're already there, and the O/S whines that they are already installed and must be uninstalled first before over-writing.I'm curious though, why did you upgrade the memory on the PPC board to 256MB? It seems to work fine with the 128MB it came with...
Anritsu MS2670A - Page 1
Forum section: electronics / testgear

author: NavyBOFH
author_rank: Contributor
timestamp: May 27, 2017, 11:15:24 pm
content: I was wondering if anyone on here has come across anything for these before? I have two that I picked up, both working and one with a recently expired calibration sticker, and one that looks fine but seems to have a blown front end and possibly tracking generator issues as well.I found a single mentioning on here that it was a military custom model, but I have not the slightest clue what the next closest model would be to look up for a service manual... or if anyone here might have a service manual for it?I would love to get the second unit fixed since the first one is being put to work pretty heavily already. Any help would be appreciated!
Vintage Calculator Exposed - Page 1
Forum section: electronics / testgear

author: wn1fju
author_rank: Frequent Contributor
timestamp: May 27, 2017, 10:05:36 pm
content: I know it's not test equipment, but I thought people might like a look inside a vintage calculator I found in a box in my basement. If I recall,I bought this in 1970 for the proud sum of $200 USD.It's a basic 4-function beast with selectable decimal points and either truncation or rounding. It also has one "memory."As far as I can figure out, the essence is a Hitachi 4-chip calculator set containing an HD 3210 keyboard interface, an HD 3211 timing/control logic, an HD 3212 ALU and an HD3214 shift/working register chip. The HN3205 is most likely the program ROM.The keyboard is magnetic. Press down on a key and it slides a magnet next to a reed relay which closes. Unlike virtually every other calculatorI've ever had, this keyboard really ought to last 1,000 years.No batteries here, just plug it into the wall. If I remember, I had this during college and had to sit by myself away from the rest of the classso I was near an AC outlet. I used this in a statistics course final exam where we could earn extra credit if, after answering an exam questionusing the statistical test they ordered, we also solved the problem with different statistical tests. The professor must have deemed that hewasn't taking a big risk, because everybody had to calculate things by hand and the mere time to do the arithmetic for other tests would beprohibitive. But he forgot about me! I think I got something like a 500 on the exam.And who doesn't like nixie tubes?

author: rsjsouza
author_rank: Super Contributor
timestamp: May 27, 2017, 10:32:26 pm
content: Pretty cool pictures. A while ago a came across a Casio AS-A that uses the same base ICs and magnetic keyboard arrangement.I did a video that can be found in the link in my signature below (in portuguese only, sorry)
LiIo battery charging software for ELV DPS5315 dual power supply - Page 1
Forum section: electronics / testgear

author: Rytikar
author_rank: Newbie
timestamp: December 29, 2016, 08:27:29 pm
content: Hi all,probably quite a niche thing, but here goes.Lately I bought and built a dual power supply fromELVin germany, theDPS5315(2*15V/3A or 1*30V/3A).I think they ship at least to Europe/EU. Me being from Denmark had no problems getting one. Nice supply for the price, I think, with the pleasure of assembling it myself on top of it. (Sort of not taking it apart but putting it together...)I saw Davesabout charging LiIo batteries with bench power supplies and found the delivered software lacking in that department.Long story short, I wrote my own and you can try it if you like. (There was that tricky part of reverse engineering the serial protocol for those in the know)Look here:Dps5315LiIoChargerThanks for you're interestRytikar

author: claytonedgeuk
author_rank: Contributor
timestamp: March 10, 2017, 11:04:37 pm
content: Hey thanks for sharing that. So you're a few months in with the dps5315 now, how are you finding it?

author: Rytikar
author_rank: Newbie
timestamp: May 27, 2017, 04:36:37 pm
content: Quote from: claytonedgeuk on March 10, 2017, 11:04:37 pmOops, sorry for the late reply.Well, serves all my needs. Was a joy to build. Worked on first try and does it well for the price. And loads my liio batteries. 😀Sent from my Pixel C using Tapatalk
Keysight 1000 X-Series Review - Page 1
Forum section: electronics / testgear

author: jusaca
author_rank: Unknown
timestamp: May 29, 2017, 07:34:30 pm
content: In the Keysight 1000 X-Series Teardown Dave mentions, that he will do a complete review in a seperate video - but I just can't find it! Can anybody help me? xDWhere is that review I'm lokking for?

author: TK
author_rank: Super Contributor
timestamp: May 29, 2017, 08:15:36 pm
content: Dave never published the review video... has a long backlog of pending reviews

author: jusaca
author_rank: Unknown
timestamp: May 30, 2017, 03:48:50 am
content: Ahh, that explains it. Too bad, I would love to see it. But i guess there are a lot of different wishes for videos, as his poll a few weeks ago showed us

author: jusaca
author_rank: Unknown
timestamp: June 01, 2017, 03:26:17 pm
content: Did he never mention when he will release the test?

author: TK
author_rank: Super Contributor
timestamp: June 01, 2017, 07:58:54 pm
content: Probably never
Opening a Testboy TB-3000 - Page 1
Forum section: electronics / testgear

author: Ochsenfrosch
author_rank: Newbie
timestamp: May 25, 2017, 07:35:22 am
content: Hi, I opened my Testboy TB-3000 multimeter. It's about 70,-€ in Germany.Have some impressions.

author: Fungus
author_rank: Super Contributor
timestamp: May 25, 2017, 07:44:41 am
content: It might just be the angles, but...these look awfully close to each other on the input protection. I think a spark might be able to jump that distance.And the soldering...

author: Fungus
author_rank: Super Contributor
timestamp: May 25, 2017, 07:47:43 am
content: Quote from: Ochsenfrosch on May 25, 2017, 07:44:02 amThat's called "calibration".Looks like the resistance was a little bit high so they added some extra solder to fix it.Quote from: Ochsenfrosch on May 25, 2017, 07:39:59 amThe design looks OK but I bet the meter they submitted for approval wasn't soldered/assembled by the same person that soldered/assembled yours.

author: Towger
author_rank: Super Contributor
timestamp: May 25, 2017, 08:07:30 am
content: Quote from: Fungus on May 25, 2017, 07:47:43 amTo quote Dave, it is done by nude virgins or old gray beards with their tongue the correct angle. But, I think you are correct, in this case old Bathild looked at the meter in a test rig and cleaned the tip of her soldering iron on the shunt.

author: Fungus
author_rank: Super Contributor
timestamp: May 25, 2017, 08:46:16 am
content: Quote from: Towger on May 25, 2017, 08:07:30 amNo, it's true!Normally they're manufactured a bit low and they put a few "nips" in them with a pair of side cutters until it reaches a known value, like this:(sort of like laser trimming but without the lasers)If it's a bit too high? Add a blob of solder!

author: Fungus
author_rank: Super Contributor
timestamp: May 25, 2017, 10:20:18 am
content: Or... they might just have been cleaning their soldering iron.

author: WackyGerman
author_rank: Regular Contributor
timestamp: May 25, 2017, 11:38:39 am
content: Horrible build quality. I am in doubt that the TÜV / CE certification is real . Scammer

author: Huluvu
author_rank: Regular Contributor
timestamp: May 25, 2017, 02:48:43 pm
content: Same issue with my TB 3000 which I posted in 2013https://www.eevblog.com/forum/testgear/soar-multimeter/msg192944/#msg192944

author: Hydrawerk
author_rank: Super Contributor
timestamp: May 25, 2017, 04:59:54 pm
content: Is this a rebranded Mastech or something??

author: stj
author_rank: Super Contributor
timestamp: May 25, 2017, 05:26:39 pm
content: Quote from: WackyGerman on May 25, 2017, 11:38:39 amthe certification is only done on a submitted device - the one they built carefully and de-fluxed first!!

author: PointyOintment
author_rank: Frequent Contributor
timestamp: May 27, 2017, 05:27:54 am
content: Quote from: Ochsenfrosch on May 25, 2017, 08:17:10 amCareful with that. When you put glue on it, I think you have to worry about creepage distance, which is greater than the clearance requirement for a given voltage. With hot glue, though, you probably couldn't easily put on a blob that's too small.
Extech CT80 AC Circuit Load Tester - Page 1
Forum section: electronics / testgear

author: joeqsmith
author_rank: Super Contributor
timestamp: May 26, 2017, 11:25:31 pm
content: Has anyone played with one? It only tests once per mode and then has to be power cycled. Pulse a large transformer like this and it may not like being saturated.http://www.extech.com/display/?id=14410
Rough testing of device isolation - Page 1
Forum section: electronics / testgear

author: orion242
author_rank: Unknown
timestamp: May 26, 2017, 06:58:15 pm
content: I have a device that I would like to just do some rough and ready testing of its isolation. In a nutshell its a 2x RS-485 to Ethernet bridge. Internal construction looks nice, has isolation slots in the pcb, they paid attention to track clearances, etc. This device is using a pair of ADM2483 (assuming they are real) as the 485 transceivers. Because the device is so cheap, I'm wondering if the transceivers have any isolation or not. Not really concerned with super accurate measurements, more a yes it can handle 500v or she smokes < 100v.Current idea is to put a Fluke 1507 across the 485 RX/TX terminals and its power input and see what happens from the lowest test voltage up to 500v and maybe right up to 1kv. See if it survives afterwords or if "she pops". This would be with the unit disconnected and powered down, only connected to the 1507.So the question, would testing it this way give any rough idea of the isolation or a complete waste of time? If not, what would be a rough test setup without $10K of gear?Trying to wrap my head around the ADM datasheet and its maximum ratings as well. If I'm reading this right (likely big IF), it can handle 2.5kv rms for 1 min. Max working insulation voltage, I assume this is in operation which I will not be testing. Input to output test voltage 1050v. Assuming that is more or less what I'll be pushing with this setup and I should see something close to insulation resistance listed of >10^9 @ 500v.Am I off in the weeds or on the right path to at least see if there is some isolation on this device?TIA!
Continuity test with Fluke TL224 - Page 1
Forum section: electronics / testgear

author: PowerNet
author_rank: Regular Contributor
timestamp: May 26, 2017, 03:12:46 am
content: Hi all,So I got my TLK-225 kit and in it is the Silicon Fluke TL224 leads, which no dout a must have.The issue is with the continuity test, I can get it to fail most of the time.I have tested it with the standard lead that came with the 87V and works every time.Has anyone else experienced this issue ?Im using the TL224 lead with the TP175 probes.Thanks

author: BMack
author_rank: Regular Contributor
timestamp: May 26, 2017, 05:02:04 am
content: I don't have that problem with my TL224s, I have several pairs of those leads as backups and have tested all. I use the TP2 and TL224s with my 87Vs. I have a set of the TP175 at work I can test.

author: retiredcaps
author_rank: Super Contributor
timestamp: May 26, 2017, 05:07:14 am
content: You should be able to narrow down if one of the test leads/connectors is broken or not with another pair of good ones by mixing and matching everything.
Siglent retractable hook tip removal - Page 1
Forum section: electronics / testgear

author: Skyhein
author_rank: Newbie
timestamp: May 27, 2017, 02:37:03 am
content: Hi,today I found a new Siglent oscilloscope in my mail, and in the package I found two PP215 probes with retractable hook tips.And I hate it to post such a dump and silly question with my first posting, but I can't wait for support people returning on Monday, so here it is:How do I remove the retractable hook tips?Greetings

author: mdszy
author_rank: Unknown
timestamp: May 27, 2017, 02:55:12 am
content: On my Rigol scope they just pull right off. Just give them a tug and they should pop off, and then you can just snap them back on when you want to use them.

author: Skyhein
author_rank: Newbie
timestamp: May 27, 2017, 03:04:41 am
content: Ok, I used the force (Luke) and it came off. Thank you very much!

author: mdszy
author_rank: Unknown
timestamp: May 27, 2017, 03:05:27 am
content: Quote from: Skyhein on May 27, 2017, 03:04:41 amYou're very welcome, happy to help!