hybridfree/eevblog-posts huggingface dataset:
Ho do I view  original source signal from circuit on an oscilloscope? - Page 1
Forum section: electronics / testgear

author: Rene
author_rank: Regular Contributor
timestamp: January 08, 2015, 01:57:52 am
content: Hello,I have a super simple circuit (one capacitor only) connected to an oscilloscope (see Picture1). Note that the circuit is powered by a pulsating signal and not by a typical sinusoidal signal.This is all good and simple until I start speeding up the frequency. If I speed up the frequency high enough, the signal across the capacitor (the signal being measured) starts to get very distorted until it looks nothing like the original source signal.So what i need to know right now is where do I connect the oscilloscope to get a readout of the source signal (not the signal across the capacitor). is this even possible?For reference, I have included a depiction of an oscilloscope screen showing the original signal in blue, and the signal across the capacitor in yellow (see Picture2). These are not the real signals but I thought I would include the picture to help get my point across.Thanks.

author: tautech
author_rank: Super Contributor
timestamp: January 08, 2015, 03:51:13 am
content: Think about this: how stiff is the source of the waveform?As Frequency increases there is less time for the cap to charge and to charge a cap takes current.What happens to the stored voltage in the cap when the waveform is low?If a diode is placed in series it will let current pass on the postive part of the waveform and prevent cap discharge on the falling waveform.If the source is not stiff the voltage with staircase up with each pulse until an equilibrium is reached.There are several parameters missing from your question, voltage, cap size, current source and frequency.EACH has a bearing on a accurate full reply.Hopefully hints have been given.

author: free_electron
author_rank: Super Contributor
timestamp: January 08, 2015, 09:24:22 am
content: Your generator has a 50 ohm output. So essentially you are tapping the node of an rc filter. As frequency goes up, that 50 phms becomes dominant and you see, what you call distortion, which is actually integration due to the output impedance of the generator.Then there is the impedance of the wires between generator out and capacitor as well.In short : you cannot see the original signal. You would need to pick it up before the output amplifier in the signal generator , after the last voltage gain stage, before the current gain stage.An easier solution is to insert a unity gain omplifier between generator out and the capacitor. Then you can take the signal going in to the amplifier as reference.What are you trying to do ?

author: KedasProbe
author_rank: Frequent Contributor
timestamp: January 08, 2015, 09:25:45 am
content: You are not measuring your capacitor 'circuit' you are measuring how good your source is when you try to cripple it by adding a heavy load (small resistance).With an ideal source the capacitor will not change the signal.
Rigol 2072 Duty Cycle Measurement Question - Page 1
Forum section: electronics / testgear

author: Electro Fan
author_rank: Super Contributor
timestamp: January 09, 2015, 10:08:56 am
content: Most of the time Duty Cycle is displayed as a percentage such as 50.0%. Sometimes it is displayed as something such as 288.8m%; occasionally it toggles back and for between the xx.x% format and the xxx.xm% format. Any idea what the xxx.xm% format means? Thx, EF

author: andtfoot
author_rank: Unknown
timestamp: January 09, 2015, 10:39:20 am
content: I'd say is m = milli, so 288.8m% would be 0.2888%.
Slow Tektronix TLA software? - Page 1
Forum section: electronics / testgear

author: nctnico
author_rank: Super Contributor
timestamp: January 06, 2015, 10:39:39 pm
content: I'm wondering is anyone has managed to somehow speedup the TLA software from Tektronix (especially version 5.x). Even when going through a saved dataset on a fast PC it is slow like a snail.

author: TiN
author_rank: Super Contributor
timestamp: January 07, 2015, 04:06:27 am
content: Use 6.1, it's somehow little faster, but not so much
Chinese Frequency Counters - Page 1
Forum section: electronics / testgear

author: ximac
author_rank: Contributor
timestamp: January 07, 2015, 01:38:45 am
content: Hi,I wish to upgrade the frequency range of my counter and so there are a number of options open to me. Apart from a prescaler, one of them is to keep the existing counter and to purchase for occasional use an inexpensive, low-microwave counter as presently available. So, I wonder what experience anyone has had of these as they are very attractive at the price offered.TIA - Joe

author: nctnico
author_rank: Super Contributor
timestamp: January 07, 2015, 02:10:09 am
content: I have one and it works. I think I posted some measurements on it's sensitivity. The only problem is that the absence of a user manual needs some dumb 'pushing buttons and see what happens' to figure out how it works.
MCM electronics AFC909 15% off code no longer working. - Page 1
Forum section: electronics / testgear

author: djnickthemix
author_rank: Newbie
timestamp: January 06, 2015, 06:42:30 pm
content: anyone else have a working 15 % off promo code for mcm? I've spent a lot with them in 2014. I even called and asked nicely if there's any new current promo codes available and the woman just plain said no. She didn't even offer any hope!
Obtaining Main System/Acquisition Board for Agilent 2000-X Series DSO - Page 1
Forum section: electronics / testgear

author: newcoppiceman
author_rank: Newbie
timestamp: January 06, 2015, 04:40:58 am
content: Here's something a little bit left-field...I'm in the market for a new 'scope and while there are some great DSO/MSOs out there I'd quite like to emulate Agilent's DSO6xx4L 1U low-profile range (which dates from about 2006).If (a big "if"?) I can get hold of the main "acquisition board" for an Agilent DSO-X 2024A I would then "box-up" with the required PSU boards (0950-5277 - Power Supply Switching AC/DC 125W; 75019-66424 - Line Filter) and some forced ventilation. I'd crack-open a DSOXLAN plug-in module for a VGA display output to an external monitor and control via a PC over LAN using the Agilent "Real Scope" interface (which emulates the instrument's controls quite nicely).Unfortunately the acquisition board for the 2000-X series is not listed on p150 of the 2000/3000-X series service guide as a replaceable part - these boards are only available for the 3000-X series, and then only for 350MHz up, as per the service policy outlined in the guide. As I would also need the following options...DSOX2MSODSOX2MEMUPDSOX2EMBD... I'm kinda hoping I can do a deal with Agilent/Keysight somehow.This would make for an interesting project in itself, I think - what do others think? It should be viable as it's only the same approach as Agilent took with their "L" variant of the 6000 series. Advantages include being able to mount the 'scope enclosure under-bench and using an "as-big-as-you-like" wall mounted VGA display. (Incidentally, while the display is available over the LAN its update rate is woefully poor - maybe two or three times per second - while the VGA output faithfully reflects the instrument's fast-update-rate display.)A similar service guide for Tek instruments is also available on-line and this suggests the same trick could be played with their range - not sure how good the PC control interface is, though,It's proving hard to find any "under-the-hood" information on the Hameg/Rohde & Schwarz HMO2024, but that could be another contender.

author: iRad
author_rank: Regular Contributor
timestamp: January 06, 2015, 04:33:29 pm
content: It would be smarter just to buy a used scope, as the few parts alone would probably cost more than an entirely new scope...

author: newcoppiceman
author_rank: Newbie
timestamp: January 06, 2015, 05:02:29 pm
content: Yeah, you may be right. I've been monitoring all the usual "used" sources for some months but the pickings have actually been very slim (plenty of old CRT ones, of course). I may have to settle for a 3000-series PicoScope!
Does anyone have the schematic of DPO3034 scope? - Page 1
Forum section: electronics / testgear

author: Hugoneus
author_rank: Frequent Contributor
timestamp: August 07, 2014, 10:42:13 pm
content: I have a broken DPO3034 which does not start up. A bunch of lights turn on and then go off. Nothing on display. I suspect that perhaps the Flash memory is corrupt. If anyone has had this similar issue, please let me know. Thanks!

author: nctnico
author_rank: Super Contributor
timestamp: August 07, 2014, 11:45:38 pm
content: If the scope has a VGA output try that. Otherwise use a light to shine on the display under different angles to see if there is anything on the screen. Maybe the backlight is broken.

author: Hugoneus
author_rank: Frequent Contributor
timestamp: August 08, 2014, 12:00:58 am
content: Quote from: nctnico on August 07, 2014, 11:45:38 pmThanks, I have already tried both of those. I also checked the clock source on the PowerPC processor and FPGA on the board. They both seem OK.

author: drago
author_rank: Contributor
timestamp: January 06, 2015, 12:49:41 pm
content: Hi Shahriar,Have you fixed your scope?
new FLIR C2 thermal camera, coming March 2015 - Page 1
Forum section: electronics / testgear

author: ixfd64
author_rank: Frequent Contributor
timestamp: January 08, 2015, 05:48:15 pm
content: http://www.flir.com/instruments/content/?id=66732Looks pretty cool...

author: Maxlor
author_rank: Frequent Contributor
timestamp: January 08, 2015, 06:44:00 pm
content: https://www.eevblog.com/forum/testgear/new-flir-products/msg582221/
EEV Argus 2 fault - Page 1
Forum section: electronics / testgear

author: budo
author_rank: Newbie
timestamp: January 05, 2015, 02:10:53 pm
content: Hi all,Does anybody here have any experience with fault finding on these old thermal imagers?I have one which displays a white screen (except the batt status displays ok). The iris appears to shut itself almost fully on startup. Opening the iris allows the camera to display a faint image though it is very a bit bleached out and only low detail of heat differences are shown. Contrast/brightness adjustments do not help much so I am thinking it could be some sort of AGC problem.The power switch seems somewhat temperamental too, sometimes operating/sometimes not/sometimes comes on and then goes off again as the camera begins to power up. I guess this could mean some power supply missing to some part of the boards but I cannot locate it at the moment.Any ideas/pointers greatly appreciated
Vellemen HPG1 Opinions? - Page 1
Forum section: electronics / testgear

author: K3mHtH
author_rank: Regular Contributor
timestamp: January 03, 2015, 08:45:41 pm
content: Hey guys,Does anyone own a Velleman HPG1? I'm looking for a function generator, mainly to test audio gear and the portability looks great on this thing.I'm thinking of buying it from tequipment if anyone has the discount code as well, that'd be great!

author: commongrounder
author_rank: Frequent Contributor
timestamp: January 03, 2015, 09:13:54 pm
content: Yes, I have one in my little tool bag. It works great for audio. The sweep function tracks well, and there is plenty of output drive. The controls have a bit of a learning curve, and the screen is a bit low res, but once you get used to them, it is fine. The sine distortion in the audio band is reasonably low. You can't beat the size! I recommend it.

author: K3mHtH
author_rank: Regular Contributor
timestamp: January 04, 2015, 08:20:04 pm
content: Thanks mate,looks like this will be a good addition to my portable tool box. Just gotta remember to keep the battery charged.
FLIR software calling home - Page 1
Forum section: electronics / testgear

author: Bud
author_rank: Super Contributor
timestamp: November 13, 2014, 02:25:20 am
content: Just to remind FLIR owners that FLIR Tools send home your data each time you start the software, over an unsecure connection, as follows-http://internalstore.flir.com:80/?productname=FLIR%20Tools&licensefileid=XXXXX&licenseserialnumber=&computername=XXXXX&username=XXXXXAlso sends some data to Google. Initially this was found by users in the Teardown thread here:https://www.eevblog.com/forum/testgear/flir-e4-thermal-imaging-camera-teardown/2025/So here we go a year later, nothing changed.I blocked the URL on my HTTP filter, the software did not seem to care.

author: Bud
author_rank: Super Contributor
timestamp: January 02, 2015, 05:56:49 pm
content: Just promoting the above message to the top of the section as information for new E4 owners.

author: Noise Floor
author_rank: Regular Contributor
timestamp: January 03, 2015, 09:53:24 pm
content: Crap. Thanks for the post, I had no idea.I don't really have an issue with software sending back some data if it helps them build a better product, but encrypt it, don't send unnecessary personal details and provide me a means to opt out.
UK Rigol warranty with firmware updates? - Page 1
Forum section: electronics / testgear

author: Solder_Junkie
author_rank: Frequent Contributor
timestamp: January 04, 2015, 10:59:18 am
content: I wonder if Telonic (UK Rigol importer and distributor) are as pedantic over user upgraded firmware as their support page suggests?I am concerned about their implied terms and conditions:"Alternatively, if you are not concerned about limiting your UK warranty, you may choose to apply direct to RIGOL for firmware updates via the link on this M/f page:http://www.rigolna.com/tech-support/Understandably, if you decide to apply direct to RIGOL your actions can still invalidate your Telonic warranty - in this case please expect to continue your enquiry directly via RIGOL the manufacturer. Telonic Instruments Ltd. andwww.RIGOL-ukTeam bears no responsibility for your use of materials obtained in this way unless you first obtain express written permission from RIGOL-uk.co.uk and conduct the upgrade at your own risk."I doubt these terms are enforcible, but has anyone clashed with them over upgraded firmware?

author: AndyC_772
author_rank: Super Contributor
timestamp: January 04, 2015, 11:36:25 am
content: I've found Telonic extremely helpful and supportive, although the support they can offer is of course limited by what firmware Rigol makes available. Sometimes their hands are tied.Rigol's firmware upgrade processes can be flaky, and I think what they're trying to do is cover themselves in the event that buyers try to carry out a firmware upgrade and find something goes wrong.If you need a firmware update, get it through Telonic and ask them to talk you through the update process. Chances are they'll be happy to do so once they've tried it themselves and can be sure the upgrade works and won't brick your hardware.

author: Solder_Junkie
author_rank: Frequent Contributor
timestamp: January 04, 2015, 03:20:30 pm
content: Thanks Andy, I have one of the "trigger jitter" DS1054Z 'scopes which resulted in a firmware release from Rigol USA a few days ago. I'll phone Telonic on Monday and see what their take on it is.Over the years I've done dozens of firmware updates on other equipment, but haven't seen such a performance as Rigol seem to have.If properly designed, firmware updates can be interrupted and re-done, down graded, etc. without "bricking" the hardware.Still a DS1054Z is cheap for a reason...Dave

author: DanielS
author_rank: Frequent Contributor
timestamp: January 04, 2015, 03:41:28 pm
content: Quote from: Solder_Junkie on January 04, 2015, 03:20:30 pmIn Rigol's case, if you brick the main firmware, you can still go into bootloader mode to update it from there.

author: jc101
author_rank: Frequent Contributor
timestamp: January 04, 2015, 06:06:51 pm
content: I've not had any problems with Telonic either, always been very helpful and easy to talk to.All round nice people IMHO and happy to point people their way.
UT70A - Frequency Measurement shows .000 kHz - Page 1
Forum section: electronics / testgear

author: Didix
author_rank: Regular Contributor
timestamp: January 03, 2015, 06:00:30 pm
content: Hi thereI got a couple DMMs plus an UTG9002C frequency generator (FG).When I measure the signal (1V, 2kHz or 20kHz) from my FG,the UT70A shows .000 kHz, wheras my other DMMs show the right frequency.Other measurement ranges (V, A, Ohm) on the UT70A work fine.Any ideas appreciated!

author: electr_peter
author_rank: Unknown
timestamp: January 03, 2015, 06:47:43 pm
content: What mode of DMM do you use for frequency?I do not know about UT70A, but typical DMM has 3 types/modes of frequency measurement:V DC -> Hz - this mode picks up even low signals and signals with high frequencyV AC -> Hz - this mode is limited in frequency measurement due to very limited DMM AC BW and possible AC couplingseparate Hz mode - it is typically similar to DC, depends on DMMThere is some limitation on lowest detectable signal level on all modes as well. See DMM manual for this.Check DMM mode and connection. Is DMM in a good condition (good AC/DC accuracy, battery is full)?

author: PA0PBZ
author_rank: Super Contributor
timestamp: January 03, 2015, 07:49:56 pm
content: Just browsing the manual, it has a seperate Freq setting, 2Khz - 10Mhz, sensivity Less/Equal 0.8V, but they don't say if it is PP or RMS.So if you have it on the 10Mhz setting and is does not show anything even with 2V you might have a problem...

author: Didix
author_rank: Regular Contributor
timestamp: January 03, 2015, 08:18:27 pm
content: right, only one dedicated position.My other DMMs show frequency above around 0.7..0.8V.The other modes work well (V, A, Ohm).I will check the battery.EDIT: My Fluke 76 says9.37V if UT70A is off9.04V if UT70A is on

author: PA0PBZ
author_rank: Super Contributor
timestamp: January 03, 2015, 08:34:50 pm
content: Did you try more than 1V input?

author: Didix
author_rank: Regular Contributor
timestamp: January 03, 2015, 08:51:30 pm
content: Problem solved!It's the sensitivity.I had my 20dB Button in. So I could not go higher than 2.4V.With Sinus nothing happens.Changing to Square helps. Now it triggers above about 1.0V.Taking out the 20dB Button and going back to Sinus I pushed it now up.It triggers above 5V.Well, I did not expect that it needs that much VoltageThe user manual says: Sensitivity better than 0.8 VrmsThanx guys for helping that fast !!
HP 8904A and HP 3456A automated frequency response measurement - Page 1
Forum section: electronics / testgear

author: davorin
author_rank: Unknown
timestamp: January 05, 2015, 01:44:33 pm
content: Thought I share some little code I did for testing a LC audio filter as my sons chess computer he got for christmas had a loud and annoying beep (o;It is written in Python and uses the pyplot library accessing the linux-gpib under Ubuntu:Code:import matplotlib.pyplot as pltimport timefrom Gpib import *fig = plt.figure()x = []y = []frequencies = [20, 30, 40, 50, 60, 80, 100, 150, 200, 300, 400, 500, 600, 800, 1000, 1200, 1500, 2000, 3000, 4000, 5000, 6000, 8000, 10000, 12000, 15000, 18000, 20000]dmm = Gpib(0,3)dds = Gpib(0,7)dds.write('PS')dds.write('GM0')dds.write('FC1OF')dds.write('APA1VL')dds.write('WFASI')dmm.write('F2')dmm.write('M4')time.sleep(0.5)for f in frequencies:dds.write('FRA' + str(f) + 'HZ')time.sleep(0.5)level = dmm.read(60)x.append(f)y.append(level)plt.scatter(f, level)plt.draw()print f, levelplt.xscale('log')plt.xlabel('Frequency (Hz)')plt.ylabel('Level (dBm)')plt.ylim(-20,3)plt.xlim(20,20000)plt.grid()plt.show()fig.savefig('frequency.png')Feedback, corrections and of course enhancements very welcome (o;And it comes out with HP 8904A directly connected to the 3456A:

author: davorin
author_rank: Unknown
timestamp: January 05, 2015, 06:27:48 pm
content: Did some modifications to the code...mainly for having a nice graph in the end...Surprisingly the 3456A is quite flat in the audio spectrum and well above as the plot shows....measured here from 5Hz to 600kHzCode:import matplotlib.pyplot as pltimport timeimport numpy as npfrom Gpib import *fig = plt.figure(figsize=(20,10))ax = fig.add_subplot(1,1,1)x = []y = []frequencies = [5, 8, 10, 12, 15, 18, 20, 25, 30, 40, 50, 60, 80, 100, 120, 150, 175, 200, 250, 300, 400, 500, 600, 800, 1000, 1200, 1500, 1750, 2000, 2500, 3000, 4000, 5000, 6000, 8000, 10000, 12000, 15000, 17500, 20000, 25000, 30000, 40000, 50000, 60000, 80000, 100000, 200000, 300000, 400000, 500000, 600000]dmm = Gpib(0,3)dds = Gpib(0,7)#Set 8904A output to 1.41V and sinewavedds.write('PS')dds.write('GM0')dds.write('FC1OF')dds.write('APA1.41VL')dds.write('WFASI')# Switch 3456A to ACV and db log readingdmm.write('F2')dmm.write('M9')time.sleep(0.5)for f in frequencies:dds.write('FRA' + str(f) + 'HZ')time.sleep(0.5)level = dmm.read(60)time.sleep(0.5)x.append(f)y.append(level)print f, levelplt.plot(x,y, linewidth = 2)plt.draw()plt.xscale('log')plt.xlabel('Frequency (Hz)')plt.ylabel('Level (dBm)')plt.ylim(-20,3)plt.xlim(0,600000)major_ticks = np.arange(-18, 3, 3)minor_ticks = np.arange(-20, 3, 1)ax.set_yticks(major_ticks)ax.set_yticks(minor_ticks, minor = True)ax.grid(b=True, which='major', color='k', linestyle='-')ax.grid(b=True, which='minor', color='r', linestyle='--')plt.show()fig.savefig('frequency.png')Maybe someone has a good idea how generate a log array of frequencies in python? ;-)

author: bingo600
author_rank: Super Contributor
timestamp: January 05, 2015, 07:29:43 pm
content: Thanx for this neat little trick/Bingo
Marconi 2032 need firmware  - Page 1
Forum section: electronics / testgear

author: EMUD
author_rank: Regular Contributor
timestamp: November 22, 2014, 07:47:22 pm
content: Hello,I need the a bin file for a Marconi 2031/2032 for its display unit. I have a Marconi 2032 with a 7.001 main software but the display has the software revision 7.003 . So the display and the system did not work together. So I need the binary for the display (27C512) version 7.001 .Please help.ThanksEMUD

author: KK
author_rank: Regular Contributor
timestamp: January 03, 2015, 05:33:19 pm
content: I have a complete set of the files for the software and LCD I extracted but it is for OS 4.005.
BenchVue & WinXP Compatibility? - Page 1
Forum section: electronics / testgear

author: LabSpokane
author_rank: Super Contributor
timestamp: January 02, 2015, 04:52:19 pm
content: Does anyone know if BenchVue v2.5 is compatible with WinXP? I have installed on XP, but under a VMWare virtual machine on my Mac and am having a bunch of display / performance issues. (I don't think it's the virtual machine, as this is the only issue I've had with it) I see in the spec sheets that there is a reference to XP, but under supported operating systems, I only see Win7 and 8.Thanks in advance for any insight.

author: LabSpokane
author_rank: Super Contributor
timestamp: January 02, 2015, 06:45:31 pm
content: Holy sh*t! I just got a PM from Keysight of all people. They're on it.You just have to love that kind of service. Makes buying new gear an easy decision.

author: HighVoltage
author_rank: Super Contributor
timestamp: January 02, 2015, 07:54:54 pm
content: I have BenchVue v2.5 running on Win Xp and Win 7 and both systems work perfecly alright.

author: LabSpokane
author_rank: Super Contributor
timestamp: January 03, 2015, 05:22:11 am
content: Got it fixed. I had to turn down the Windows graphics accelerator settings in the display setup.Thanks for the feedback. Knowing that it would work was 90% of the battle.
Tequipment has a very good price on Fluke 376 today... - Page 1
Forum section: electronics / testgear

author: alank2
author_rank: Super Contributor
timestamp: December 31, 2014, 08:38:58 pm
content: Hi Everyone,http://www.tequipment.net/Fluke376.html?OrderItemId=1226287You can stack the eev blog discount on top of this too to make it even better, plus I think Fluke is still doing their free gift you add to that (today is the last day)http://media.fluke.com/documents/6003238A-EN-T3-measure-up-redemption-form-p.pdfHappy New Year,Alan

author: retiredcaps
author_rank: Super Contributor
timestamp: December 31, 2014, 10:02:43 pm
content: I never understood why you have to put something in your cart in order to see the price? To me, it reeks of sleaze. HUGE

author: aroby
author_rank: Regular Contributor
timestamp: December 31, 2014, 10:16:59 pm
content: Quote from: retiredcaps on December 31, 2014, 10:02:43 pmIt's usually because the vendors' contracts with the suppliers forbid them from advertising a price lower than the one set in the contract.

author: alank2
author_rank: Super Contributor
timestamp: January 01, 2015, 12:53:08 am
content: I guess it showed the price because I was logged in...

author: Bud
author_rank: Super Contributor
timestamp: January 01, 2015, 07:29:40 am
content: And some vendors do not tell you shipping charge until checkout, and some do not tell it untill you have submitted the order. I usually avoid buying from such places.

author: nowlan
author_rank: Frequent Contributor
timestamp: January 01, 2015, 09:08:22 am
content: Lol. Complain about having to add to cart, then you dont tell us the price?$399.95$289.56
FISH8840 Transistor Tester Self-test question - Page 1
Forum section: electronics / testgear

author: yaputya
author_rank: Newbie
timestamp: December 31, 2014, 12:41:19 pm
content: Just received one of the popular LCR/transistor testers frm China labelled FISH8840.It powers up with the message Version 2.1It draws 172uA standby current, apparently this is a hardware design fault due to the battery monitoring voltage divider being connected directly across the battery input. You can fix it by a hack involving shifting the battery voltage divider input across to the input of the 78L05 regulator.My question is: Does anyone know how the self-test function works? If you connect all inputs (1,2,3) together and press TEST the tester does a self-test. It goes through about 8 steps and displays various info along the way. Does anyone know what this info means?Is there a manual for the FISH8840?

author: edavid
author_rank: Super Contributor
timestamp: December 31, 2014, 07:27:25 pm
content: Go directly to the other thread:https://www.eevblog.com/forum/testgear/$20-lcr-esr-transistor-checker-project/
Quake on an oscilloscope - Page 1
Forum section: electronics / testgear

author: Guni
author_rank: Regular Contributor
timestamp: December 30, 2014, 06:08:33 pm
content: Just for fun :-)Quake on an oscilloscopehttp://www.lofibucket.com/articles/oscilloscope_quake.html

author: rx8pilot
author_rank: Super Contributor
timestamp: December 30, 2014, 08:04:06 pm
content: I can only dream of having that much excess time on my hands.
Inexpensive DMM or switch with SCPI? - Page 1
Forum section: electronics / testgear

author: LaurentR
author_rank: Frequent Contributor
timestamp: December 30, 2014, 12:12:09 am
content: Hi,I am looking at a way to make 2 measurements (DCV+DCV or DCV+DCI) programmatically through SCPI (controlling a supply in steps and recording measurements).I have only one DMM (new 34461A), so I could get either another SCPI-capable DMM to measure in parallel or use some kind of switching device that I can control (also ideally through SCPI) and do the measurements in sequence.Measurement speed is not an issue. DMM accuracy and calibration status are not a must, but certainly good to have. 4 digits within spec are enough.What would be my options?I looked at cheaper DMMs:* New Rigol 3058E ~$450. USB connection* New Agilent 34450A ~$580 when Zoro runs a promotion. USB connection. I don't see those much online or on EBay so they don't seem to be popular (thinking about resell value too...).* Old Agilent 34401A $300-600 (calibrated). RS232 or GPIB. Not sure how easy/cheap are to bridge to USB (USB?RS232 connections are always finicky even with FTDI chips).* Any other inexpensive SCPI capable DMM in that price range? (new or used). I am partial to Rigol and Agilent since I'll already be using a Rigol supply and an Agilent DMM, but I am open otherwise.* Some kind of a switch device?Thanks in advance.

author: radioFlash
author_rank: Regular Contributor
timestamp: December 30, 2014, 02:28:57 am
content: I'd vote for a used 34401A. I got one from ebay for $350 in excellent condition. It didn't claim to be in calibration, but it seems to be accurate when using my 3457A and DMMCheck as a reference. I'm using a cheap USB to serial converter with it, and it works fine with BenchVue.
Test Equipment Manual Doodles - Page 1
Forum section: electronics / testgear

author: jeremyabel
author_rank: Newbie
timestamp: December 30, 2014, 12:54:23 am
content: A friend was asking me about an oscilloscope he saw on craigslist, so I looked up the manual, and found all these cute little doodles in the "don't do this to your oscilloscope" section. I know I've seen similar doodles in other manuals, but I can't remember where. Would love to get a little collection going, I'm curious how widespread this is. Really makes me feel for the little guy!The manual in question is here:http://dcfa.exa.unicen.edu.ar/lab/manuales/Osciloscopio_hitachi_v-212.pdfI love the snowman's expression here.

author: radhaz
author_rank: Regular Contributor
timestamp: December 30, 2014, 01:03:36 am
content: I've seen illustrations like that in Japanese HiFi manuals.

author: PaulAm
author_rank: Frequent Contributor
timestamp: December 30, 2014, 01:22:25 am
content: Here's one from a Tektronix 184 time mark generator schematic. I thought it amusing.

author: jeremyabel
author_rank: Newbie
timestamp: December 30, 2014, 01:57:47 am
content: Quote from: radhaz on December 30, 2014, 01:03:36 amDo you remember the brand?Quote from: PaulAm on December 30, 2014, 01:22:25 amAhaha perfect!

author: barry14
author_rank: Regular Contributor
timestamp: December 30, 2014, 02:30:55 am
content: Many old Tektronix manuals have cartoons embedded in the schematics. Some can be seen athttp://www.sm5cbw.se/tubes/humor.htm.Searching on Tektronix humor will find more of them.

author: Alex Eisenhut
author_rank: Super Contributor
timestamp: December 30, 2014, 02:32:47 am
content: http://photos1.blogger.com/blogger/2715/2091/1600/washer_woman.gifhttp://sm5cbw.se/tubes/jpg/tek-1.jpghttp://sm5cbw.se/tubes/jpg/tek-2.jpghttp://sm5cbw.se/tubes/jpg/tek-3.jpghttp://sm5cbw.se/tubes/jpg/tek-4.jpghttp://sm5cbw.se/tubes/jpg/tek-6.jpgThe classic VIC-20 user manual had a cartoon VIC explaining stuff ...

author: aargee
author_rank: Frequent Contributor
timestamp: December 30, 2014, 06:14:49 am
content: Panasonic used to have a lot of similar simple cartoons as part of their manuals for video/HiFi gear.

author: Psi
author_rank: Super Contributor
timestamp: December 30, 2014, 07:18:55 am
content: These sort of diagrams appear in car service manuals too.My nissan exa service manual has some.

author: radhaz
author_rank: Regular Contributor
timestamp: December 30, 2014, 07:30:23 am
content: It was in most of the Japanese brands user manuals from the '60 on I think.Quote from: jeremyabel on December 30, 2014, 01:57:47 am

author: DJ
author_rank: Unknown
timestamp: December 31, 2014, 02:01:45 am
content: The late Jim Williams of Linear Technology had many doodles at the end of his application notes. He was an avid collector of vintage test equipment, and may well have been inspired by Tek and others.
Touch panel oscilloscope - DSO112 - Page 1
Forum section: electronics / testgear

author: ray0812
author_rank: Newbie
timestamp: December 27, 2014, 06:15:37 pm
content: Hello folks, I am new to this forum. I am coming to introduce another toy oscilloscope - DSO112. This is a touch panel oscilloscope with low-end performance and low-end price (sensitivity is not too bad though). Just think it might find its way in the pockets of hobbyists and beginners. Here is a video about the little thinghttps://www.youtube.com/watch?v=aVAgMjQjF6Q&feature=youtu.be.More details about DSO112 can be found athttp://www.jyetech.com/Products/LcdScope/e112.php.Thank everyone for attentions!
HP 8559A repair - Page 1
Forum section: electronics / testgear

author: idpromnut
author_rank: Unknown
timestamp: December 28, 2014, 04:02:38 am
content: Several months ago I picked up an HP 8559A (with HP 853A display) for probably more than I should have. It needed a bit of work (there were a few broken wires in the SA module) and there is still an intermittent gremlin in the display power supply. The major thing that I liked about it and why I picked it up was the wide-band capabilities, 0.01 to 21GHz (in 6 bands).Of course when I was testing it out, I actually run into a problem; only the first band (from 0.01 to 3GHz) worked and all the other bands displayed the same 3GHz band. I had put this problem aside since I didn't need anything higher than 3GHz for the moment. Today I decided to have another crack at trying to fix it. Looking at the service manual for the thing, I started working my way back form the front panel switches. They all tested out OK and the correct signals were being passed back into the frequency band selection board (A7). I pulled that board out and had closer look. That is when I found the problem: 2 "crushed" op-amps. They were most likely shorted out. These were used to adjust the YTO's driver for the higher than 3GHz frequency bands. The SA must have taken quite a knock to have done that!

author: tautech
author_rank: Super Contributor
timestamp: December 28, 2014, 04:40:44 am
content: And did afix it ?

author: idpromnut
author_rank: Unknown
timestamp: December 28, 2014, 04:43:04 am
content: Quote from: tautech on December 28, 2014, 04:40:44 amA careful application of a leverage device (screwdriver) seems to have done the trickAt least I can measure signals up in the 4.5GHz range now, which is better than before.

author: tautech
author_rank: Super Contributor
timestamp: December 28, 2014, 04:52:01 am
content: Quote from: idpromnut on December 28, 2014, 04:43:04 amWell you've a little way to go to 21 Gbut thats gotto make you feel better.I've allways been tooto chase anyting like this for fear that you'd need another to fix it.

author: idpromnut
author_rank: Unknown
timestamp: December 28, 2014, 02:18:13 pm
content: The crazy thing was that it was sold "as-is" but the guy had said that it had been in good working condition when he had been using it a while back.It looks like those two op-amps were the result of some shock to the side of the unit (perhaps even in shipping) but I hadn't opened up the unit that much when I got it, and there were no pictures of the inside of the unit before I bought it.
Wiltron 560A Scalar Network Analyzer - Page 1
Forum section: electronics / testgear

author: R_G_B_
author_rank: Frequent Contributor
timestamp: December 27, 2014, 02:47:59 pm
content: Hi I managed to get this old CRT Wiltron 560A Scalar Network Analyzer off ebay for a thew pounds I know its a network analyzer, but is it worth having? I don't know why I was bidding on the thing but I ended up winning it.

author: KJDS
author_rank: Super Contributor
timestamp: December 27, 2014, 03:16:05 pm
content: It needs a swept frequency source, directional coupler or bridge and three power detectors to make it useful.

author: R_G_B_
author_rank: Frequent Contributor
timestamp: December 27, 2014, 03:17:33 pm
content: Thanks for your reply KJDS

author: G0HZU
author_rank: Super Contributor
timestamp: December 27, 2014, 03:41:44 pm
content: I have no experience in using this particular instrument but I agree with KJDS that you need a fair bit of extra hardware to make it useful.In 2014 this old analyser is probably best suited to doing research/design work (on the cheap) up at >>10GHz if you can find suitable detector probes and a swept source and couplers etc.The old HP8620C sweeper with a suitable plugin might be compatible (and cheap) but the stumbling block may be finding detector probes that are compatible and not already damaged by a previous user.

author: larry42
author_rank: Regular Contributor
timestamp: December 27, 2014, 05:46:59 pm
content: I managed to do something useful (e.g. gain vs amplitude measurement at 2-14GHz) with a 8756A - with detectors - that I borrowed. However, it required Python, an expensive power splitter, an arb. waveform gen, a microwave sig gen and a GPIB card...

author: Rupunzell
author_rank: Frequent Contributor
timestamp: December 27, 2014, 06:35:10 pm
content: This is basically a digital storage display with two very good log amplifiers with about 100db of range and 0.1 db linearity, good to about -62dbm. It needs a sweep generator to work. When properly set up it can resolve 0.10db using the store-subtract mode. Originally intended to be used with Wiltron sweep generators. Since it is Detector based, the operating bandwidth is limited by the detectors and signal source used. In theory, DC to daylight.The display was built by Tektronix as an OEM product.

author: woodchips
author_rank: Frequent Contributor
timestamp: December 28, 2014, 04:01:08 pm
content: If interested I have a spare Marconi 6581 Transmission Line Test Head which contains a Wiltron Autotester.The Marconi unit also includes a power divider, 3 way power splitter and two detectors, all working up to 20GHz.This was sold many years ago on ebay, but the buyer never paid so just been sitting in the box of RF items to be sorted, one day. I tested it when put on ebay and worked fine, but no longer have the Marconi 6500 or the Wiltron 560 to test it with.I need hardly add that these are delicate precision instruments, always use a 10dB attenuator to try and stop inadvertant destruction.The sale price on ebay was 170GBP, if interested then let me know.
BNC/SMA connectors and crimp tools - Page 1
Forum section: electronics / testgear

author: apelly
author_rank: Unknown
timestamp: December 29, 2014, 01:01:39 am
content: A while ago I bought a roll of rg174 to make some cables. I found wildly varying prices for BNC connectors and never got around to ordering any. Now is the time.1) Is there such a thing as a universal crimper for rg174/rg58?2) Can anyone recommend a source for adequate BNC/SMA/N connectors?

author: xrunner
author_rank: Super Contributor
timestamp: December 29, 2014, 01:07:40 am
content: Quote from: apelly on December 29, 2014, 01:01:39 amYep, I use one all the time. It has several jaws you can install. Get one like this -http://www.texastowers.com/ct240.htmQuoteI use this Ebay store, they are in China and supply all types of crimp connectors at a good price -http://stores.ebay.com/adapterconnectorpigtailcable/
MSO1104 How to get 1GSa/s - Page 1
Forum section: electronics / testgear

author: FrankT
author_rank: Regular Contributor
timestamp: December 27, 2014, 02:44:35 am
content: I'm a scope noob, so be gentle...I'm playing around and trying to learn how to use my scope. There is an Acquire menu which lets me set the Mem Depth and Sa Rate. Sa Rate always seems to be greyed out, and never exceeds 500MSa/s. (1 channel on)Is that the maxium? Or do I need to be in some special mode to see 1GSa/s?Thanks,Frank

author: FrankT
author_rank: Regular Contributor
timestamp: December 27, 2014, 03:18:06 am
content: Solved this myself. I was in auto trigger mode. I got the faster sample rate (and full memory depth) when in normal mode.Thanks.
My first thread - calibrator "Burster 4409" - I'm looking circuit diagram - Page 1
Forum section: electronics / testgear

author: old-papa
author_rank: Newbie
timestamp: December 26, 2014, 11:10:22 am
content: Hello,my nick is "Old Papa" from Germany. I have been a good 45 years with "Electronics" go.Unfortunately, only with bad English, so write / I read about "google translator"My problem: I have a Calibrator "Burster 4409" which is identical to the Escort 2000 and for Extech CMM-15. (the processor is with "Escort 39-25688-1" hereinafter) This Calibrator works well for +/-1,50Volt and +/-15.00Volt in power, unfortunately, are always -29,0mA output.Seeking a matter of service documents, or at least a circuit diagram.I suppose it was fed voltage at the output port. All components there I have checked all are ok.Who can help me?greetingOld-Papa

author: tautech
author_rank: Super Contributor
timestamp: December 26, 2014, 11:33:16 am
content: Welcome to the forum.You might find them here:http://www.manualsdrive.com/results.php?lang=en&search=BURSTER%204409-E#.VJ1GoV4Ak

author: old-papa
author_rank: Newbie
timestamp: December 26, 2014, 11:54:11 am
content: Quote from: tautech on December 26, 2014, 11:33:16 amhello,have you ever bought something there? I suspect this is a fake. No matter what you're looking for, the always offer everything! Are there times "Mumpel-2014" or "Obama-no" one ...That can not be right!greetingOld-Papa
HP 3437A System Voltmeter wrong readout - Page 1
Forum section: electronics / testgear

author: davorin
author_rank: Unknown
timestamp: July 13, 2014, 06:55:24 am
content: Good morning....I received yesterday a HP 3437A system voltmeter from an ebay seller described as fully functional....Now when I apply different voltages with my 6632B to it, the read out is always negative and doesn't match the actual voltage...Am I doing something terribly wrong here with the 3437A?For example, setting following voltages to it results in listed read out below:Code:0V -11.101V -11.202V -11.303V -11.404V -11.465V -11.56

author: davorin
author_rank: Unknown
timestamp: December 26, 2014, 03:03:30 pm
content: Finally found some time these days to have a closer look at the analogue board section...Turned out that the auto-zero circuit didn't get the 85usec pulses, which are inverted by U10, a CD4049 type CMOS Hex inverter...Also Zener diode CR222, 12V1, was broken, responsible for the -4V supply feeding the 4049 inverter....A quick hardware hack with a 4011 as a inverter replacement and connected to pin 5/7 of U10 (input) and cutting the trace of pin 4/6 for inserting the new output shows now correct voltage reading :-)
Automatize Yourself: RIGOL VISA Win32 UltraEasy Demo in Dev-C++ - Page 1
Forum section: electronics / testgear

author: msraya
author_rank: Unknown
timestamp: December 26, 2014, 09:04:25 am
content: Hello!These Christmas days I have been playing with my RIGOL oscilloscope MSO1074S-Z.I like easy Win32 API programing and I love Test Equipment Automation.I cannot find easy VISA project for Dev-C++, so, I build mine Myself.I hate Visual C++ and for the mather LabView, .NET, C# et all..I hope introduce You to Win32 Api Easy Programing,You can begin with:http://zetcode.com/gui/winapi/Put RIGOL folder in C:\ . Please report bugs.Note that my example is a Win7 64bits application and It use visa64.dll and it only works via USB cable.Anyway, USB cable is twice faster than the Ethernet connection.Good Programming!!RegardsManuel

author: msraya
author_rank: Unknown
timestamp: December 26, 2014, 10:58:14 am
content: Hello again!!I also build as a Win32 Console application the interesting Clifford Wolf DS2000 shell util from here:http://www.clifford.at/blog/index.php?/archives/128-Controlling-a-Rigol-DS2000-Scope-using-Linux.htmlI do not have DS2000 scope, so I cannot test this piece of code. I test it in MSO1074Z-S via USB and it works somewhat ;-)I am working in the waveform download code that behaves diferently from DS1000Z operation, and I will post a MSO1000Z-S shell when I finish.Note that this other application is 32 bits applications and so, It uses visa32.dll. I cannot find a Windows Readline 64bits DLL.Please Reports bugs, as I cannot test all SCPI commands!!!RegardsManuel
Sticky leatherette on older HP equipment - Page 1
Forum section: electronics / testgear

author: dom0
author_rank: Super Contributor
timestamp: December 24, 2014, 02:14:47 am
content: Everyone probably knows the green fake leather on most HP gear from the 70's onwards. It likes to become sticky, not something one wants to touch. What can I do to restore the fake leather to it's non-sticky state?

author: robrenz
author_rank: Super Contributor
timestamp: December 24, 2014, 02:24:58 am
content: IMOScrub with citrus based cleaner on magic sponge to get rid of most of the tackiness. Then apply"Mothers Back to Black" to restore the luster and get a smooth non tacky finish. Has worked very well for me on many of my restorations shown on this forum.Edit:Example here

author: taylor12
author_rank: Contributor
timestamp: December 24, 2014, 02:34:54 am
content: i have used isopropyl alcohol on some paper towels it removed the stick and didnt seem to harm it.

author: cncjerry
author_rank: Unknown
timestamp: December 26, 2014, 06:39:21 am
content: I believe the stick is from someone using acetone to clean it. I use Simple Green and Mothers spray on finish wax and it seems to clean and protect it.

author: Guni
author_rank: Regular Contributor
timestamp: December 26, 2014, 12:34:10 pm
content: Use Xylene. Is is the best to remove old/new stickers. Safe for most of plastics. Sometimes can wash up paint so make a test before.
DS1102E weird math results - Page 1
Forum section: electronics / testgear

author: BigE
author_rank: Newbie
timestamp: December 18, 2014, 07:15:18 pm
content: Hi, total forum newbie here, looking for a possible explanation of what might be happening with my scope.This is the second scope, first one was sent back .. would not boot up. This one does, and appears to work right.... but this has me stumped.I exported these two screenshots the other day, and it occurred to me, that the math does not make sense. The first shot is of the ripple on two voltage rails in a power amp. In the first shot, CH1 and CH2 are AC coupled, showing +/- power supply rails. One of the channels is inverted.The second shot shows math trace of CH1 + CH2.I was expecting to see the math trace to be near zero -- ie CH1 + Invert(CH2). This does not appear to be the case.Both shots use the same vertical and horizontal scale.

author: T3sl4co1l
author_rank: Super Contributor
timestamp: December 18, 2014, 08:42:18 pm
content: What kind of filtering is enabled? (Bandwidth limit, hi res, DPO effect, ??)The noise appears much greater than the noise from each waveform, but it may be masked by display or acquisition method, I don't know. Often the MATH channel is displayed without anything, like DPO or filtering, so it looks noisier.If you're trying to look at just the low frequency ripple (total difference, or total imbalance, as the case may be), you should limit bandwidth somehow (filtering, hi res mode, etc.) to get a clean trace. Likewise, if you want to inspect the HF ripple or whatever it is, you might do the opposite, or use a better measurement method (cap coupled direct to coax..?!). And if it's interference (internal, or nearby radio stations, nasty switchers, etc.), better probing technique and filtering is helpful.Tim

author: BigE
author_rank: Newbie
timestamp: December 19, 2014, 04:02:55 pm
content: Could this be from improper technique?The noise is from an amp, and the probe references were attached to the speaker ground... ie, the PS zero volt line.

author: BigE
author_rank: Newbie
timestamp: December 19, 2014, 08:31:10 pm
content: Oh, and no filtering at all was enabled.

author: vargoal
author_rank: Regular Contributor
timestamp: December 26, 2014, 04:55:45 am
content: Just a thought check the voltage range. I think it's adding to a zero then auto-ranging which makes the noise amplified. Just a thought but I am more of a software guy who uses oscilloscopes rarely.

author: cncjerry
author_rank: Unknown
timestamp: December 26, 2014, 06:55:19 am
content: The noise looks about double what it should be. I am trying to think of a calculation that would cause this. Taking out the dominant sine wave you have about one division of noise on each so an algebraic sum would be about two divisions of noise. You can't expect the noise to sum algebraically to zero because one is inverted unless the samples were perfectly aligned which will never happen except like in that one area on the trace. If you were doing like an Avg PSD summation then yes, it could be zero. Can you compare the FFT of the summation to the original signal?