hybridfree/eevblog-posts huggingface dataset:
TESTING UNITS AVAILABLE RESONABLE PRICES - Page 1
Forum section: electronics / testgear

author: floridavendor
author_rank: Contributor
timestamp: May 18, 2015, 04:20:58 am
content: ANYBODY INTERESTED IN ANY ANRITSU OR AGILENT UNITS, OR OTHER TESTING EQUIPMENT FROM ANY MANUFACTURER ? WE HAVE MANY UNITS AT VERY REASONABLE PRICES . PLEASE CONTACT ME IF YOU ARE INTERESTED IN MORE INFORMATION OF WHAT WE HAVE AVAILABLE, OR IF YOU HAVE ANYBODY THAT MAY BE INTERESTED MAYBE WE CAN DO SOME BUSINESS TOGETHER. ALL IN GREAT CONDITION, CALIBRATED , WITH PAPER WORK . PLEASE LET ME KNOW AS SOON AS POSSIBLE . THANK YOU MY EMAIL IS : FLORIDAVENDOR06@GMAIL.COM . CONTACT ME ALSO IF YOU HAVE SOME UNITS AVAILABLE FOR SALE AT REASONABLE PRICES , I HAVE ALL TYPE OF CUSTOMERS FOR TESTING UNITS

author: floridavendor
author_rank: Contributor
timestamp: May 18, 2015, 05:17:02 am
content: By the way I know I wrote this post in all caps. Just wanted to get peoples attention . I am new to this forum I am a broker and I work directly with several reputable distributors in the us and I can get you good prices on units. just message me if interested. Tell me what you are looking for, and I will check and see if they have it available. I can help you negotiate on a good price for what you need . thank you

author: floridavendor
author_rank: Contributor
timestamp: May 18, 2015, 05:44:03 am
content: Here are just a few of the units my distributor has available . I have pictures , serial numbers , and paper work available just message me . Thank you.ANRITSU MS2038CANRITSU CALIBRATION KITAnritsu-MS2713EHP-AGILENT-HP-8720BANRITSU MW8219AANRITSU-MT8212E

author: slurry
author_rank: Regular Contributor
timestamp: May 18, 2015, 05:55:44 am
content: An serious instrumentvendor using a anonymous gmail-adress?I notice a sligth smell of scam here...

author: Simon
author_rank: Unknown
timestamp: May 18, 2015, 09:39:07 am
content: Original poster has been banned
AM-270 pricing -- why was it $70 in 2012 and over $100 now?? - Page 1
Forum section: electronics / testgear

author: andersoj68
author_rank: Newbie
timestamp: March 29, 2015, 06:44:34 pm
content: Hi All.I'm looking for a replacement multimeter for home use, which covers a pretty wide range of applications since I do medical device design. I don't want to get into all the specifics of my needs, and I know that opinions on meters are all over the forums. However, one item I can't seem to get my head around is that the price of the Amprobe AM-270 has seemingly increased significantly in the last few years.Given that the price is twice that of a UNI-T UT61E or a AM-530, as well as about a dozen other meters right at that $50 price point. I can't see the benefit of spending 2x, especially knowing that the meter was significantly cheaper in the past. Does anyone have some insight as to why the price has increased so much, and is it really worth the extra cost over the UNI-T or AM-530? I would say at $75 the AM-270 would be the meter I want, but when I'm looking over $100 it makes much less sense.I would welcome thoughts on other meters as well, but I seem to keep circling back the AM-270.Thanks!

author: Halvmand
author_rank: Regular Contributor
timestamp: March 29, 2015, 08:22:26 pm
content: I have to make a shout out for the Amprobe.I've got the 520-eur which equals the 530 but without the true rms capability.I've seen the ut-61e taken apart, and it does not compare to the build quality of the amprobe.Only complaints so far has been the default ac voltage measurement when selecting volts.

author: Lightages
author_rank: Unknown
timestamp: March 29, 2015, 08:32:25 pm
content: Yes, I have been surprised at the price hikes on the AM-270. I really think it a mistake as you can get the BM-257 for only $135 shipped to your door, and to me it is a better meter.

author: jhufford
author_rank: Contributor
timestamp: May 18, 2015, 02:27:42 am
content: I'm considering this meter too. I wonder if the price increase has to do with that it seems like there was the original am-270 with 4 buttons across the top and now the am-270 has 8 buttons across the top.. Could they have found an error and when fixing it, they upgraded some stuff and came out with the 8 button version and increased the price?
Keysight X2014 strange display  - Page 1
Forum section: electronics / testgear

author: klaus1311
author_rank: Contributor
timestamp: May 16, 2015, 11:43:52 am
content: Hello,this is my first post in this forum. My name is Klaus and I'm living in Germany Bavaria.I've been playing with my KeySight InfiniiVision X2014. I got a signal shown, I can't explain myself. Perhaps someone from the forum can. If I switch off "math", the signal looks normal. But in the background it still looks slightly modulated.My Settings:Loop from WaveGen to Channel1WaveGen:Squarewave 5MHz, 1V PP, Offset 0, Dutycycle 50% Output Load 50Ohm, Add Noise 0%Channel1:Coupling DC, Noise Reject None, HF_Reject None, Holdoff 40usNormal ModeFirmware Version 2.39Klaus

author: tom66
author_rank: Super Contributor
timestamp: May 16, 2015, 11:56:24 am
content: Could be an aliasing effect. The math function may be causing the unit to slow down the processing or sample rate causing the aliasing to happen when it otherwise would not normally happen.

author: AndyC_772
author_rank: Super Contributor
timestamp: May 16, 2015, 12:08:09 pm
content: You're sampling a 5 MHz square wave at 10 MHz. Maybe the WaveGen clock and the sampling clock aren't synchronised?

author: 0xdeadbeef
author_rank: Super Contributor
timestamp: May 16, 2015, 12:28:23 pm
content: What does "BW" mean? Maybe bandwidth limit on?

author: dom0
author_rank: Super Contributor
timestamp: May 16, 2015, 01:49:02 pm
content: Sampling a 5 MHz square wave with 10 MHz is bound to alias.

author: MarkL
author_rank: Unknown
timestamp: May 16, 2015, 04:06:47 pm
content: It is aliasing. The 2000X and 3000X scopes turn off anti-alias dithering when certain math functions are turned on, such as FFT.Discussed previously:https://www.eevblog.com/forum/testgear/agilent-dsox-2000-aliasing/msg569835/#msg569835

author: Hydrawerk
author_rank: Super Contributor
timestamp: May 17, 2015, 05:50:23 pm
content: Quote from: 0xdeadbeef on May 16, 2015, 12:28:23 pmYes. When bandwidth limit is on, the maximum bandwidth for the channel isapproximately 20 MHz.
crocodile clips - Page 1
Forum section: electronics / testgear

author: artag
author_rank: Super Contributor
timestamp: May 16, 2015, 05:30:25 pm
content: All my miniature crocodile clips - even on expensive things like HP scope probe earth clips - seem to be dying. Perhaps I'm too heavy handed - as I press on the back, the clips twist sideways as well as opening. When they close, the jaws don't meet neatly and thin wires aren't held tight.I think what happens is that the sides of the clips bend inward, so that the 'inner' half no longer fills the 'outer' half. Then there's nothing to help them stay parallel, and they wander all over the place.Has anyone else found this ? Is there a cure ?Maybe I can replace them with better quality clips. Ransack my older HP probes, perhaps (no, not really!). Have you got any suggestion for clips made of thick copper rather than thin nickel-plated steel ? I've wondered whether filling the inside with solder - or even hot glue - would stop them bending, but it's a fiddly job.On a related note, I have many older clip leads with a soft PVC cover. The red ones (and only the red ones) have gone so stiff that it now takes a huge force to open them. Is this a failure mode of aged PVC, specific to red colouring (I know that sounds odd, but many pigments have ageing problems).

author: jeroen79
author_rank: Frequent Contributor
timestamp: May 16, 2015, 07:02:39 pm
content: To prevent them getting bent you should take care not to press too hard when opening them and especially avoid lateral forces.You could also put a little block of plastic or piece of metal tubing inside the clip around the axle to brace the clips.You may have to remove and replace the riveted axle for that but perhaps you could use some sort of putty or make something in two parts that can be place around the axle.Another thing I can think of is to apply some sort of heat treatment to alter the clip's metallurgical properties and make them stiffer.
Understanding oscilloscopes schematics - Page 1
Forum section: electronics / testgear

author: taldarin
author_rank: Newbie
timestamp: May 16, 2015, 02:45:15 pm
content: Hello guys,I am new in this great forum.I have found here great schematics for Hantek and similar oscilloscopes:https://www.eevblog.com/forum/testgear/hantek-tekway-dso-hack-get-200mhz-bw-for-free/msg214613/#msg214613made by tinhead user.Overall the architecture of device is pretty clear for me (at least I think so), but I am not understanding a few parts of it.1. In front ends they placed 3 stage amplification circuit: FET input buffer, Variable gain diff-amp, diff amp for driving ADCIt's clear that we need VGA in front end but why they use this FET buffer? VGA itself should have pretty high impedance input. Also why we need another buffer after VGA to drive ADC? Even in datasheet of AD8370 we see ADC interfacing (maybe varicap is reason of it) ?2. In Offset Control circuit they use push-pull buffers e.g. for OFFSET2-CH1 voltage. Why they doing it for just driving VGA input? As I understand simple opamp buffer configuration should work fine.3. In Offset Control circuit they use just one shift register and one DAC for controlling 9 types of offset voltages. How did they hold offset values of 9 outputs? The outputs can be different values right?So it will be great if some one helps me to understand this aspects of the design.

author: dom0
author_rank: Super Contributor
timestamp: May 16, 2015, 03:19:49 pm
content: The VGA has a differential input impedance of about 200 ?. The scope has a 1 M? / 30 pF (or so) input impedance. So you need a buffer. A FET buffer.Quote from: taldarin on May 16, 2015, 02:45:15 pmThe TLV274 is likely not stable with 10+ µF capactive load (while they don't give a number for the output resistance the low output drive ability suggests a high output resistance, which creates a pole with external capacitance and thus leads to phase lag), the additional push-pull buffer lowers the output resistance and thus improves loop stability (by increasing the phase margin). Still it seems they had some issues there, look at the 10 nF compensation...Quote from: taldarin on May 16, 2015, 02:45:15 pmThe 100 ? + 6.8 µF are a low pass filter, so if they multiplex the analog inputs fast enough the output voltage will be nearly constant. Although it works, I don't regard this design as very good, since the op amp inputs are essentially open circuit while not selected. A real S/H is IMHO the better solution.

author: taldarin
author_rank: Newbie
timestamp: May 16, 2015, 03:32:10 pm
content: Thanks a lot dom0.Now I understand that I need be more attentive to details of design.For 3rd point I was thinking about fast switching technique, but I think that it is not good enough to use in this kind of device.
Fluke 73-2 touch hold function - Page 1
Forum section: electronics / testgear

author: jonsig
author_rank: Contributor
timestamp: May 13, 2015, 09:22:34 pm
content: Hi i got this beast .I´m wondering if its broken because the only way for me to use thetouch hold featureis to select ohms , volts_dc etc. Andhold the yellow select button in for few seconds before it finishes booting up.And when its in touch hold mode the only way to turn it off is to reset the meter , turn it to off position .

author: retiredcaps
author_rank: Super Contributor
timestamp: May 13, 2015, 10:01:05 pm
content: Working as per manual.

author: jonsig
author_rank: Contributor
timestamp: May 14, 2015, 01:24:18 am
content: Thank you , i have only found service manuals so far .

author: retiredcaps
author_rank: Super Contributor
timestamp: May 14, 2015, 03:49:43 am
content: An user manual is here.https://www.cs.washington.edu/1999/lab/facilities/hwlab/docs/mans/77______umeng0200.pdf
New HIOKI DT4255 model with fuse at voltage terminal - Page 1
Forum section: electronics / testgear

author: KGB
author_rank: Contributor
timestamp: May 15, 2015, 04:36:35 pm
content: I do not see advantage of this. What do you think?http://www.hioki.com/file.php?t=news&iid=3_59

author: Vgkid
author_rank: Super Contributor
timestamp: May 15, 2015, 05:17:35 pm
content: If it hsd current than I would see it, but voltage measurements typically have an input impedance of about 10meg ohms. It would take a high voltage to blow a fuse for that...

author: Lightages
author_rank: Unknown
timestamp: May 15, 2015, 05:26:43 pm
content: Hmm, strange. I can only think this is to help prevent the kinds of accidents we have read about here with people getting severely burned or killed by connecting a meter across a circuit it wasn't rated for. There is currently no standard for this but it could help.
Rigol DS1000Z trigger edge type, alternate. Is this a bug? - Page 1
Forum section: electronics / testgear

author: oliver602
author_rank: Regular Contributor
timestamp: May 11, 2015, 10:53:33 pm
content: Recently got a Rigol DS1054Z. While playing around with it as a newbie I discovered behaviour which I thought was odd. Perhaps someone could help me understand what is going on here. Or maybe it is a bug.I connect channel 1 to the test signal and select Trigger type as Edge and select Slope as alternate. See attached image. I expected to see both rising and falling edge displayed. But instead it only displays one edge, sometimes randomly switching between rising and falling. It seams to behave as expected when scale is at 1us or less per division. My previous scope (a DS1052E) displays both edges regardless of scale.

author: alsetalokin4017
author_rank: Super Contributor
timestamp: May 12, 2015, 09:19:58 am
content: What's the frequency of your test signal? I can get similar behaviour but only for a very narrow range of frequency settings.

author: ebastler
author_rank: Super Contributor
timestamp: May 12, 2015, 09:39:47 am
content: Quote from: oliver602 on May 11, 2015, 10:53:33 pmThe scope's waveform update rate may happen to be in sync with the test signal you are looking at. Hence, whenever the scope is ready to look for another trigger, the test signal is approaching another low > high transition. I understand that you are measuring the built-in 1 kHz square wave, which is most likely controlled by the same master clock as the scope's data acquisition system; so the signal may actually be phase-locked to the waveform update rate.As mentioned by alsetalokin4017, I would expect this behavior to occur only for specific settings of the signal frequency and/or sampling rate and timebase. What happens if you change the timebase, number of samples, trigger hold-off time etc.?

author: alsetalokin4017
author_rank: Super Contributor
timestamp: May 13, 2015, 05:16:53 pm
content: Ah... so by "test signal" what is meant is the scope's Probe Calibrator output. I see now.Yes, when using the Probe Calibrator output I get exactly the same behaviour as described. And I believe that ebastler has given the correct explanation. It's not exactly a "bug" unless you want to include all the quirks of DSOs vs Analog scopes as bugs. It's a sampling error, that can be avoided by using different settings on the scope.

author: electr_peter
author_rank: Unknown
timestamp: May 13, 2015, 05:56:02 pm
content: Positive (or negative) signal slope is in sync with osciloscope's waveform update time and retrigger time. This behaviour is normal and expected under some circumstances."Alternate trigger" means that scope will trigger on both rising and falling edges. However, it does not mean that it will trigger on rising, then falling, then rising edge. Word "alternate" is used in a sense "use either falling or rising edge, whichever happens first".
Rigol Scope Probe to BNC Adapter - Page 1
Forum section: electronics / testgear

author: Electro Fan
author_rank: Super Contributor
timestamp: May 11, 2015, 06:08:09 am
content: Anyone have a good source in the U.S. for the BNC to scope probe adapter shown at about 14:35 into Dave's video - that would work with a Rigol RP3300A (10:1) probe? (Is the Rigol probe 3.5mm?Also, how about the banana plug binding post insert that makes the 90 degree banana plug to banana plug connection (also at 14:35)?

author: tggzzz
author_rank: Super Contributor
timestamp: May 11, 2015, 09:18:36 am
content: Quote from: Electro Fan on May 11, 2015, 06:08:09 amIf you want to look at PSUs, "high" impedance is irrelevant: just use ordinary 50ohm cable terminated in 50ohms at the scope.If you want to look at digital signals, use a "low impedance Z0 probe" - which peversely has ahigherimpedance than so-called low impedance probes.FFI, seehttps://entertaininghacks.wordpress.com/library-2/scope-probe-reference-material/

author: tautech
author_rank: Super Contributor
timestamp: May 11, 2015, 09:53:04 am
content: Quote from: Electro Fan on May 11, 2015, 06:08:09 amBit of discussion on exactly this on the last page of this thread:https://www.eevblog.com/forum/testgear/scope-probes-as-supplied-by-rigol-for-the-low-end-scopes-a-discussion/75/

author: smgvbest
author_rank: Unknown
timestamp: May 12, 2015, 07:55:17 pm
content: I orders these from Cal Test Electronics on Amazon for a pack of 10 @ $35 UShttp://www.amazon.com/gp/product/B009QBSKE2/ref=oh_aui_detailpage_o09_s00?ie=UTF8&psc=1and these probe covers also pack of 10 @ $20 UShttp://www.amazon.com/gp/product/B009QBSHM2/ref=oh_aui_detailpage_o09_s00?ie=UTF8&psc=1Seem to work fine for my needs
OR-X Model 402 Arbitrary Sweep Programmable Generator - Page 1
Forum section: electronics / testgear

author: wilhe_jo
author_rank: Regular Contributor
timestamp: May 11, 2015, 05:20:50 pm
content: Hi there!Got this piece of kit for a very reasonable price in working condition. Does anyone have a manual for it?Regards,Johann

author: wilhe_jo
author_rank: Regular Contributor
timestamp: May 12, 2015, 12:10:25 pm
content: I need to say, I wasn't that confident to get support for such an old product but OR-X is very, very, very responsive!Thanks, guys!If you also need the manual, just drop them a mail (info@or-x.com).You'll get the most parts of the 402A manual and the important sections for the 402 (402 and 402A just differ by the max-frequency).Sadly this manual does not contain schematics. So does someone has a paper-version or some PDFs?73
Manual for Saunders 110 HF crystal impedance meter - Page 1
Forum section: electronics / testgear

author: TimFox
author_rank: Super Contributor
timestamp: May 11, 2015, 07:14:21 pm
content: Does anyone have a pdf of this manual available, or a source for the manual?My usual sources (including vendors) do not have this model.

author: PA0PBZ
author_rank: Super Contributor
timestamp: May 12, 2015, 09:54:25 am
content: Did you ask Saunders?http://www.saunders-assoc.com/
Replacing busted old handheld scope - Page 1
Forum section: electronics / testgear

author: Mesozoic
author_rank: Newbie
timestamp: May 11, 2015, 10:45:50 pm
content: This is my 1st post, so I'll provide a bit of introduction. I'm a professional software engineer, having spent 10 years in the video game industry, now working mainly with embedded systems on fuel injection and autopilots. I bought my first scope in 2008 to help debug issues found in automotive and motorcycle fuel injection systems. It is a Protek 860 60 MHz handheld unit. While it has performed admirably when it's been functional, it's not always been very reliable. The screen died after 1 year's use and after $350 USD and 8 months of wait time, I finally got it back from Protek's repair facility in Korea. It functioned well until just a few weeks ago... the screen has died AGAIN.I'm interested in replacing it with a more reliable unit and there's quite a few new offerings on the market today. I'm on a budget (need the scope for personal use), so anything over $2000 USD is out of the question and something in the sub-$1000 USD pricepoint is ideal.The Instek GDS-210 (http://www.tequipment.net/Instek/GDS-210/Digital-Oscilloscopes/) looks interesting, as does the BK Precision 2512 (http://www.tequipment.net/BK/2512/, although it does not have isolated inputs. Are isolated inputs worth doubling the price of a scope?

author: tautech
author_rank: Super Contributor
timestamp: May 11, 2015, 11:03:13 pm
content: Welcome to the forum.Have a look at the Siglent SHS series, the 800 range having common BNC's and the 1000 range has isolated inputs.http://www.siglentamerica.com/pd.aspx?tid=2&T=1In the couple of decades that isolated inputs have been available in DSO's they have always been much dearer, but it's a great feature IMO, not needing Differential probes to ensure channel reference isolation.

author: Muxr
author_rank: Super Contributor
timestamp: May 11, 2015, 11:22:25 pm
content: Perhaps outdated a bit but Mike did a review on the Owon HDS3102M-N while back.

author: R_G_B_
author_rank: Frequent Contributor
timestamp: May 12, 2015, 10:32:45 pm
content: Tektronix ths720 is a good hand held scope it has isolated channels and 100Mhz bandwidth. Or fluke 199 or 200 series second hand.

author: Mesozoic
author_rank: Newbie
timestamp: May 13, 2015, 06:30:45 pm
content: The Owon review seems to indicate that it's not a complete steaming pile, which is interesting because it's Chinese!I'm seeing that Protek has been absorbed by GSI and is now GSI-Protek. They are listing an attractively priced and updated handheld scope, but of course, I'm unsure of whether anyone has any reviews for it:http://www.gsi-protek.com/#!1000s/c1tfv

author: Howardlong
author_rank: Super Contributor
timestamp: May 13, 2015, 07:18:55 pm
content: The Protek 1000 series is the same as the Hantek DSO1000B series I believe. I did a brief comparison between the Owon And the Hantek herehttps://www.eevblog.com/forum/testgear/owon-hds3102m-n-handheld-scope-review-teardown/msg639550/#msg639550

author: Mesozoic
author_rank: Newbie
timestamp: May 13, 2015, 10:34:48 pm
content: Thank you so much!
Tektronix 2465 Power Switch - Page 1
Forum section: electronics / testgear

author: flynwill
author_rank: Regular Contributor
timestamp: May 12, 2015, 12:01:39 am
content: The power switch on my 2465 suffered an ohmic failure a few weeks back (and from the amount of smell I expect far more damage than just a cooked switch).I finally got around to the repair and thought I would post because I know there is at least one other forum member out there with the same failed switch. (And this switch is probably common to a lot of Tektronix scopes of the era).The original is by ITT/Shadow (do they still exist?) but it turns out that this part is still being made. The replacement is C&K part number "NE18 2U EE P 6AMP" and is available at Mouserhttp://www.mouser.com/Search/ProductDetail.aspx?R=NE18_2U_EE_P_6AMPvirtualkey61110000virtualkey611-NE182UEEP6AMPIf you try to compare that part number to the coding listed in the published spec sheet however it doesn't make any sense. It took a bit of guesswork to get the right thing. I presume that C&K is in the process of changing the part number system for these parts and hasn't gotten the datasheet updated yet.In any case the new part is a perfect match (except for the nice pretty green color instead of black). The little plastic cover that Tektronix had put over the old part to protect service personnel from the exposed leads on the top of the old switch fits. But it isn't needed since the new part does not have the exposed metal there.Of course while I have it open I noticed a pair of dodgy looking capacitors, one clearly starting to leak and the other with a bulging top. They are the line filters for the +/- 15 V supplies. They were listed as 180 uF -10/+100% so I decided to replace with 220 uF +/- 20%. (do they still sell caps with that sort of specification any more? It used to be common.)Hope this is helpful.
Help me about using oscilloscope ? - Page 1
Forum section: electronics / testgear

author: Nhan95
author_rank: Contributor
timestamp: May 11, 2015, 01:22:10 am
content: When I use analog oscilloscope in the experiment, sometimes I work with sine wave or square wave, my teacher asked me to choose DC mode for channel 0 and channel 1 or I will face with wrong result. Uhm, I feel confused. Could you help me when we use DC or AC mode?

author: xrunner
author_rank: Super Contributor
timestamp: May 11, 2015, 01:27:19 am
content: If the sine wave or square wave has a DC bias either pos. or Neg, then you need to be DC coupled or you won't be able to see the offset. AC coupling will remove any DC biasing of a waveform.

author: Paul Moir
author_rank: Frequent Contributor
timestamp: May 11, 2015, 01:37:08 am
content: Another way understanding it is to see what the switch actually does. When I was younger, I could only afford old tube based 5MHz bandwidth oscilloscopes, which were pretty horrible but how they worked was obvious just by looking. The AC coupling switch simply put a 0.1uF capacitor in series with your probe lead. That way all DC was blocked to the vertical amplifier.

author: Lightages
author_rank: Unknown
timestamp: May 11, 2015, 01:47:34 am
content: Before asking for any help with basic use of an oscilloscope, everyone should watch the video in this thread.https://www.eevblog.com/forum/beginners/oscilloscope-training-class-(long)/

author: pascal_sweden
author_rank: Super Contributor
timestamp: May 11, 2015, 01:55:03 am
content: Or you could download this document from Tektronixhttp://info.tek.com/www-xyzs-of-oscilloscopes-primer.html

author: xrunner
author_rank: Super Contributor
timestamp: May 11, 2015, 01:58:13 am
content: Quote from: Nhan95 on May 11, 2015, 01:22:10 amI'm thinking - is the teacher teaching you these things? Did you ask the teacher? Just thinking out loud on this end.
Aoyue 8800 desoldering gun - Page 1
Forum section: electronics / testgear

author: dav
author_rank: Regular Contributor
timestamp: May 10, 2015, 02:58:14 pm
content: Hi to all,what do you think about this gun, for a non professional use?It seems well made (Vs the ZD985) and with reasonable price.Unfortunately the Hakko one costs too too much in EU
ET310A Handheld 10MHz 50MS/s Oscilloscope & True RMS Multimeter - Page 1
Forum section: electronics / testgear

author: pascal_sweden
author_rank: Super Contributor
timestamp: May 06, 2015, 10:56:14 pm
content: Is there anybody here who has used this handheld scope? Is it usable? What are your findings?http://www.aliexpress.com/store/product/Handheld-10MHz-50MSa-s-Oscilloscope-Scopemeter-True-RMS-Multimeter-2in1-USB-ET310A/917544_725426067.htmlhttp://www.ebay.com/itm/Handheld-10MHz-50MSa-s-Oscilloscope-Scopemeter-True-RMS-Multimeter-2in1-USB-/171077028387

author: Lightages
author_rank: Unknown
timestamp: May 07, 2015, 01:20:05 am
content: The first thing I noticed when I saw this is that it doesn't have a BNC connector and no probe. So to use it with a scope probe you need an adapter. 10MHz? Not with any fidelity without a proper input. I would avoid it.

author: R_G_B_
author_rank: Frequent Contributor
timestamp: May 07, 2015, 04:38:39 pm
content: Get a second hand tek scope meter or a pocket sized hps140. If you just want to do quick checks.

author: macboy
author_rank: Super Contributor
timestamp: May 07, 2015, 07:22:55 pm
content: DC accuracy is specified as 0.75% +- 10 counts. With only 4000 counts full scale, this amounts to +/- 1% with a full scale reading and +/- 3.25% with a 0.1 of full scale reading (i.e. lowest reading before switching to next lower range). That is awful. The accuracy for other functions is even worse. Granted, it might be more accurate than specified, but that is a $150 risk.

author: daybyter
author_rank: Frequent Contributor
timestamp: May 07, 2015, 10:51:09 pm
content: You can also measure a c64 with a hantek 6022be? That's only a 60,- risk? And it's 20 MHz ?

author: pascal_sweden
author_rank: Super Contributor
timestamp: May 11, 2015, 01:39:52 am
content: Maybe you can turn this unit in a Gameboy Advance
Small test Keysight U1461A and  understanding of MOV's - Page 1
Forum section: electronics / testgear

author: mswhin63
author_rank: Frequent Contributor
timestamp: May 10, 2015, 01:57:58 pm
content: Hi All,Receive a nice meter from Keysight, a U1461A Insulation Tester and reviewed it on the Element14 community website.After doing a review (newbie) I look at a power supply that failed on switching and found the meter was perfect for testing MOV's. There is a lot mention on how good MOV's are in products but not much on evaluations. Thought I would give it a try.https://youtu.be/zXwohns8qJgI am not the best editor or producer so keep that in mind when looking at it. I hope to make improvements in future videos including better lighting. Am moving to a new place in about 3 week from the original post and hope to set-up a better lab there.

author: Len
author_rank: Frequent Contributor
timestamp: May 10, 2015, 03:34:25 pm
content: YouTube has messed up your video link.They've been doing this a lot in the last couple of weeks.Please re-post the link using "https" instead of "http" - I think that will fix it.

author: mswhin63
author_rank: Frequent Contributor
timestamp: May 11, 2015, 12:09:06 am
content: Thanks Len, YouTube can be a pain in the arse sometimes.
TPI-1001-A Synthesizer, any experience? - Page 1
Forum section: electronics / testgear

author: dadler
author_rank: Unknown
timestamp: May 10, 2015, 08:31:44 pm
content: Anyone have any experience with this unit:http://www.rf-consultant.com/I am referring to the top model, TPI-1001-A. It has some nice extra features over the lower models.I recently purchased the lowest model in the series, the simple "TPI Synthesizer", and I think it works great for what it is, but kinda wish I would have purchased the power calibrated version. I don't want a second round of buyer's remorse, and was thinking of moving up to the top model.Note that these devices only output a square wave, so the output is filled with harmonics of the main frequency. This affects all of the models, which does limit some of the utility of these devices.Anyways, just wondering if anyone has any experience with the TPI-1001-A.
Test leads - Page 1
Forum section: electronics / testgear

author: trevwhite
author_rank: Frequent Contributor
timestamp: May 09, 2015, 09:44:59 am
content: I was looking for some nice test leads. 4 wire jobs and Farnell have the following.http://uk.farnell.com/keithley/5808/test-lead-set-1-17m/dp/2131247http://uk.farnell.com/keithley/5809/set-clip-lead-kelvin/dp/2131248http://uk.farnell.com/aim-tti-instruments/lcr-k-clip/set-kelvin-clip-bnc-lcr400/dp/3812406?MER=baynote-3812406-prI really can not figure out how come they are so so expensive. Are they really worth it? Has anyone bought these leads? Anyone got a suggestion for something of decent quality that is cheaper?Trev

author: Wytnucls
author_rank: Super Contributor
timestamp: May 09, 2015, 09:49:17 am
content: Assemble you own. Franki in Hong Kong sells a good kit.

author: Smith
author_rank: Frequent Contributor
timestamp: May 09, 2015, 02:21:00 pm
content: I have wondered myself the same question a few weeks ago. I gues they don't sell a lot of these, wich will increase the price drasticly. Off course Keithley stuff is expensive (and good quality), and the Pomona have BNC, wich will increase its price too.Unless its for the boss, making your own seems like a smart thing to do.

author: trevwhite
author_rank: Frequent Contributor
timestamp: May 10, 2015, 12:10:19 pm
content: I think they make enough to get the price down...

author: HighVoltage
author_rank: Super Contributor
timestamp: May 10, 2015, 12:42:05 pm
content: In the last few years, I have built my own 4-Wire Kelvin test leads, since I was never happy with the expensive sets on the market.I use LiFY cable and gold plated MultiContact banana plugs and for every day precision use, they are just perfect.
Can Anybody ID This Antique Meter?  - Page 1
Forum section: electronics / testgear

author: Steve Wayne
author_rank: Contributor
timestamp: May 09, 2015, 11:49:31 pm
content: I picked up this meter recently and can’t identify the make & model. The ID plate has been removed. Anybody know what it is? It's a heavy bastard with tube circuitry. I was told that in it's day, it was extremely accurate.

author: c4757p
author_rank: Super Contributor
timestamp: May 09, 2015, 11:57:56 pm
content: Um... just out of curiosity, what are you trying to accomplish by adding "LOOK>" to the end of the subject...?

author: PaulAm
author_rank: Frequent Contributor
timestamp: May 10, 2015, 12:27:52 am
content: I'd guess a VTVM made for military use. It's fairly unusual to see a round meter face on a VTVM.Take a picture of the insides and post it. You might find a clue inside when you do that.

author: Vgkid
author_rank: Super Contributor
timestamp: May 10, 2015, 03:24:50 am
content: I'm guessing military. I believe that face plate was added later. it covers up some of the words on the meter.

author: JackOfVA
author_rank: Unknown
timestamp: May 10, 2015, 12:10:07 pm
content: US Military VTVM, model A/N USM-116Operating and repair manual athttp://bama.edebris.com/download/military/an-usm116/usm116.pdfI should add that in the 1950's and '60's the US Government took the position that it could buy equipment from HP or Tektronix and then put out a bid that (in the US Government's view) permitted other companies to duplicate the HP or Tektronix equipment, without regard for patents held by the original manufacturer. From what I can see, the USM-116 is a US Government contractor knock off of an HP410 VTVM.Tektronix ultimately sued the US Government and several of the knock-off contractors for millions of dollars in patent claims for this practice and eventually (10 years or so) won.Please note that in many cases, the cloned knockoffs did not not work nearly as well as the original HP or Tektronix designs because there was a great deal of non-patented and non-obvious design, component specification, calibration procedure, etc., that separated a real HP or Tek instrument from the low bid knockoffs. Some clone manufacturers did much better jobs than others in duplicating the original manufacturer's level of performance.
Rigol DS1000Z and MSO1000Z exporting waveform to computer? - Page 1
Forum section: electronics / testgear

author: aviphysics
author_rank: Contributor
timestamp: January 20, 2015, 04:34:12 pm
content: I want to export the full waveform from the Rigol to my computer; so I can do a FFT of the entire waveform, instead of just what is on screen.Would someone mind directing me towards a guide on exporting or capturing the waveform? Also, is it possible to do this without the licence for wavefore record/playback? My scope is an MSO1074z.Having to keep the scope attached to the computer over USB or Ethernet would be perfectly fine.

author: damago1
author_rank: Newbie
timestamp: May 05, 2015, 11:31:17 am
content: Hi,There is a very nice and simple programm to automate this task. Oscilloscope companion. See this web page:http://ogrodowa.gosiewski.pl/publish/OscilloscopeCompanion/The program is able to download* visible part (usually 1000+points) (normal)* all live downloadable data (Maximum)* in STOP mode it can download full memory dump (RAW)and there is automation built into this programm, it can automatically create CSV file upon every waveform fetch and it can automatically copy this file to clipboard or save to disk in different variants.The same for screenshots and measurements.The programm is free to use with Rigol scopes.

author: Fenichel
author_rank: Contributor
timestamp: May 06, 2015, 12:35:29 am
content: Have other people had satisfactory results with this program? On my desktop machine (Windows 7/64), it crashes immediately after displaying its welcome screen.

author: damago1
author_rank: Newbie
timestamp: May 08, 2015, 04:56:19 pm
content: Did you install National Instruments VISA-NS as required by application prerequisities?Can you post here the crash report?

author: Fenichel
author_rank: Contributor
timestamp: May 09, 2015, 04:52:26 pm
content: I reinstalled it and it works. I don't know what was wrong, but it doesn't matter now. Thanks for your (potential) help.
Siglent 1102CML FFT Peaks - Page 1
Forum section: electronics / testgear

author: ronsch
author_rank: Newbie
timestamp: May 07, 2015, 05:05:10 pm
content: I recently purchased a Siglent SDS 1102CML (100Mz) scope and was using it to look at some noise on a power supply. I noticed two stable peaks in the FFT at 50Mz and 100Mz which remained even when I removed the probes.. I am relatively new to scopes and am wondering if it is typical to have FFT peaks on harmonics of the scope frequency. I have attached a screenshot. Any suggestions are welcome.Ron

author: tautech
author_rank: Super Contributor
timestamp: May 07, 2015, 09:54:54 pm
content: Quote from: ronsch on May 07, 2015, 05:05:10 pmWelcome to the forum.It is normal to see all sorts of garbage if the probes are not terminated to a DUT.Internally the SDS1000 series have 3 clocks, 25, 30 and 100MHz. (check the Service manual)Even the lowest BW model in the SDS1**2C*L has the same clocks.BTW to check PSU noise/ripple one would normally use AC input coupling and mV/div amplitude setting, then adjust timebase and triggering to analyse the displayed waveform.
LeCroy WR620Zi PowerUp Options - Page 1
Forum section: electronics / testgear

author: Isamun
author_rank: Regular Contributor
timestamp: May 07, 2015, 04:12:26 pm
content: We have an WR620Zi in our automated test system. The rack is powered through a UPS and all the instruments turn on when the UPS main switch is pressed, except the LeCroy. Any ideas work around this? How to enter the BIOS on these scopes? Anyone experiment with wake on LAN on these?
Scope probe problem - Page 1
Forum section: electronics / testgear

author: ktulu
author_rank: Regular Contributor
timestamp: May 06, 2015, 03:57:07 pm
content: I have a Hameg X10 oscilloscope probe, and a 25MHz bw analoge scope.(and a 10MHz scope also)I am unable to compensate the probe using the built in variable cap. It is under compensated, and has some high overshoot aswell. (see attachment, it shows the two extremes I can adjust)I was trying to pull the probe apart (to maybe change the cap) without success.There is a second adjustment hole that hides another little pot. (i guess for high frequency compensation?)Unfortunately there is no model number, or bandwith written onto the probe, only HAMEG a few times on the cable itself.I don't belive it is such a high bw probe, that the compensation rage is not enough for my 25MHz scope. (the adjustments are in the tip, not the scope end)What could be wrong? Is there any way to correct this so I can use the probe?Thanks.

author: tautech
author_rank: Super Contributor
timestamp: May 06, 2015, 08:26:42 pm
content: Quote from: ktulu on May 06, 2015, 03:57:07 pmLooking at your photos, I would say you could as somewhere between these extremes would be right.However some probes DO NOT have the range of adjustment to compensate on some scopes.Only the datasheet for the probe and knowledge of the scope input capacitance can confirm they will match.

author: ktulu
author_rank: Regular Contributor
timestamp: May 07, 2015, 06:48:28 am
content: Like in picture 336 is the best I can get. Turning the pot either way, it gets under compensated. (going towards the other picture)Only if someone here recognizes the probe, and provides a model number, I can search for data sheet.The scope has a max input capacitance of 36pF according to the manual.Weird is, I also have an Agilent 10074C 150MHz probe, and I am able to just get it compensated. It is right on the edge.What about the weird overshoots on the rising and falling edges?

author: tautech
author_rank: Super Contributor
timestamp: May 07, 2015, 07:22:10 am
content: Are you using the scope's 1 KHz Cal output?Try a cable connection just to be sure its not the problem.Just twist it around the Cal terminal and poke the other end into the BNC. GND not required for this check.Many use P6100 1:1, 10:1 probes, cheap and fine for all normal use.http://www.ebay.com/itm/Two-P6100-DC-100MHZ-Oscilloscope-Scope-Clip-Probe-100MHz-For-Tektronix-HP-GA-/181607249293?pt=LH_DefaultDomain_15&hash=item2a48a2b58d

author: ktulu
author_rank: Regular Contributor
timestamp: May 07, 2015, 07:40:38 am
content: Yes I am using the cal output, which is a perfect square connected directly.

author: tautech
author_rank: Super Contributor
timestamp: May 07, 2015, 08:13:07 am
content: Quote from: ktulu on May 07, 2015, 07:40:38 amTime for new probes.
Handheld RF Power Meter - Page 1
Forum section: electronics / testgear

author: Electro Fan
author_rank: Super Contributor
timestamp: May 06, 2015, 09:43:00 pm
content: Anyone have any experience with something like this?http://www.ebay.com/itm/RF-Power-Meter-Frequency-Counter-GY561-with-SMA-F-to-SMA-F-Cable/301589574803?_trksid=p5411.c100169.m2942&_trkparms=aid%3D555012%26algo%3DPW.MBE%26ao%3D1%26asc%3D20140131123815%26meid%3D6c4749bc7af9410a96f9828c5ab614be%26pid%3D100169%26rk%3D3%26rkt%3D5%26sd%3D390466057374Seems like a decent deal if it works from 1 MHz to 2.4 GHz.Is there a preferred unit that goes from about 100 kHz to 3 GHz? (Or maybe 6 GHz?)

author: xwarp
author_rank: Frequent Contributor
timestamp: May 07, 2015, 07:26:40 am
content: I'm thinking about getting one of these:eBay auction: #http://www.ebay.com/itm/RF-power-meter-0-500Mhz-80-10-dBm-1602-backlight-LCD-/121349108597?pt=LH_DefaultDomain_0&hash=item1c40f87375#ht_3649wt_719
Crude video review of Luyang YB4325. - Page 1
Forum section: electronics / testgear

author: technix
author_rank: Super Contributor
timestamp: May 05, 2015, 05:19:29 pm
content: I don't exactly know what to say, so here is what I can do so far.(BTW, how to embed it?)

author: Shock
author_rank: Super Contributor
timestamp: May 05, 2015, 07:55:09 pm
content: You're off to a good start, as a viewer people are probably interested in the specs of the oscilloscope so it makes good viewing to run down the purchase history, tell a few stories, throw in the specs as you go (just out of the manual or off the web is fine). That way you can build your videos out a little. You can also do as many videos on the scope as you like so don't feel you need to stop there. If you think it's interesting someone else will.Drop the "s" in "https" and it should automatically embed in pages on this forum.

author: technix
author_rank: Super Contributor
timestamp: May 05, 2015, 07:57:57 pm
content: Quote from: Shock on May 05, 2015, 07:55:09 pmThanks for the pointer, I will make a better video next time... Probably about my Zhenxing DT-890 DMM? That would be a trip down the memory lane - it is older than I am.

author: Hydrawerk
author_rank: Super Contributor
timestamp: May 05, 2015, 08:24:00 pm
content: Isn't that scope a rebadged version of a GW Instek CRT scope?

author: technix
author_rank: Super Contributor
timestamp: May 05, 2015, 08:40:31 pm
content: Quote from: Hydrawerk on May 05, 2015, 08:24:00 pmNo.GW Instek does not have the digital reading options (noticed the lines and digits around the graph?) and this one used rotary encoders and relays to operate the attenuator and time base oscillator.

author: Hydrawerk
author_rank: Super Contributor
timestamp: May 07, 2015, 03:05:07 pm
content: GW Instek has many types of analog scopes, some of them have readouts and rotary encoders.http://www.gwinstek.com/en-global/products/Oscilloscopes/Analog_Oscilloscopes/GOS-6100http://www.gwinstek.com/en-global/products/Oscilloscopes/Real-time_Digital_Storage_Oscilloscopes/GRS-6000A

author: technix
author_rank: Super Contributor
timestamp: May 07, 2015, 04:11:23 pm
content: Quote from: Hydrawerk on May 07, 2015, 03:05:07 pmNeither look like mine.
A quick question about the Rigol DP832 power supply. - Page 1
Forum section: electronics / testgear

author: Spork Schivago
author_rank: Frequent Contributor
timestamp: May 06, 2015, 04:37:43 am
content: Hello,I just ordered a Rigol DP832 power supply the other day. It should be here tomorrow. I was reading through the manual to try and get an idea of how to use it and I came across a warning I don't really understand. I've just started learning how to design my own circuits and haven't gotten very far. I fix computers for a living though and I'm sure I can find a use for this power supply in my repair work along with the circuits I'm building to learn how they all work. Anyways, here's the part in the manual that I don't really follow:Do Not Provide Power for the Active Load.In order to avoid the anti-irrigation current which leads to the power control loop outof control and damages the powered device, this power supply can only providepower for the pure load without the current output function.Could someone please explain to me what this means? Thanks!

author: Skimask
author_rank: Super Contributor
timestamp: May 06, 2015, 05:17:08 am
content: What page is that on? I can't find it in my manual...

author: rob77
author_rank: Super Contributor
timestamp: May 06, 2015, 05:22:35 am
content: it means you MUST NOT pump power into the supply - the supply can only provide current, can't sink current. e.g. you must not connect a load which is powered from other source as well.

author: rf-loop
author_rank: Super Contributor
timestamp: May 06, 2015, 08:32:11 am
content: Quote from: rob77 on May 06, 2015, 05:22:35 amBattery is also current source.

author: rob77
author_rank: Super Contributor
timestamp: May 06, 2015, 09:31:42 am
content: Quote from: rf-loop on May 06, 2015, 08:32:11 amONLY if the voltage of the battery is higher than the rigol's output

author: rf-loop
author_rank: Super Contributor
timestamp: May 06, 2015, 01:50:14 pm
content: Quote from: rob77 on May 06, 2015, 09:31:42 amI believe it is true with all power sources in this context.

author: Spork Schivago
author_rank: Frequent Contributor
timestamp: May 06, 2015, 04:51:11 pm
content: Quote from: Skimask on May 06, 2015, 05:17:08 amPage III, at the very end.

author: Spork Schivago
author_rank: Frequent Contributor
timestamp: May 06, 2015, 04:53:05 pm
content: Thank you guys! I really appreciate the explanation. I might of tried it one day if I was trying to get higher voltage or current than what the Rigol supplied.
Help Needed With My ( ESI 250DE RCL Bridge) - Page 1
Forum section: electronics / testgear

author: radiotek
author_rank: Contributor
timestamp: May 05, 2015, 03:26:51 am
content: Someone did some really sloppy rewiring on my ESI 250DE on the 1325 AC power pack. Ii looks like they added a resister to the output of the bridge rectifier. I still canb not believe that there was no filter capacitor after the bridge rectifier. I also measured the DC output voltage and it read 12 volts which seems a little high ? If anyone owns a ESI RCL bridge please contact me. It would be very appreciated if you could take a picture of your1325 AC power sully board so I could compare it to mine. Thanks, Frank

author: Vgkid
author_rank: Super Contributor
timestamp: May 05, 2015, 04:49:13 am
content: Unfortunately no sites have schematics for the external ac power supply, here are some manualsmaintenancehttp://www.ko4bb.com/manuals/75.140.215.49/ESI_250DE_Impedance_Bridge_Maintenance_Section.pdfmorehttp://bama.edebris.com/manuals/esi/250de

author: RJFreeman
author_rank: Regular Contributor
timestamp: May 05, 2015, 05:40:33 am
content: the power supply expects a set of Ni-cad batteries after it, these would normally act as the filter capacitors and a voltage regulator.The resistor would be to stop the Ni-cads from overcharging.

author: radiotek
author_rank: Contributor
timestamp: May 06, 2015, 02:06:55 pm
content: That explains why there isn't any filter capacitor after the bridge rectifier. Still the output voltage seems a bit high running at 12 volts but of coarse that is with no load and will probably drop down a bit under load. In my onion there should have had a safety switch so that the 1325 power pack could be isolated in case you wanted to use alkaline batteries.Also wanted to mention that if the nicads are removed and someone plugs in the AC power cord there is a good possibly that the 12 volts coming from the 1325 power pack could damage the bridge.Thanks for everyone's help.