hybridfree/eevblog-posts huggingface dataset:
Thrift Store Find -BK Precision 1541c and Bel-Merit MT-100 - Page 1
Forum section: electronics / testgear

author: mtdoc
author_rank: Super Contributor
timestamp: July 20, 2013, 11:02:24 pm
content: I was in the local GoodWill Thrift store today and sitting on the shelf with 20 yr old stereos was a BK Precision 1541c 40 MHz oscilloscope and a Bel-Merit MT-100 "All-In-One Instrument"-with triple output power supply to 50V, 0.5 amp, 2MHz Funct Gen, Frequency counter and multimeter. Never heard of this brand before...Anyone know where I might find manuals for these??. A quick google search and no joy...Both seem to work fine - though in need of a bit of cleaning up. The multimeter is a wee bit off..But for this price - I really can't complain!They'll be perfect for my boys first instruments!

author: Vgkid
author_rank: Super Contributor
timestamp: July 21, 2013, 01:11:19 am
content: pretty neat, my local thrift stores never have any interesting electronics.

author: mtdoc
author_rank: Super Contributor
timestamp: July 21, 2013, 02:34:44 am
content: Quote from: Vgkid on July 21, 2013, 01:11:19 amMine don't either. I usually look but the only worthwhile electronics I've ever bought is the occasional power strip or cable. I just happened to go in with my 7 yr old to find him some elbow and knee pads for skateboarding and found this. The funny thing is, the guy who works there and takes this stuff in and prices it saw me plugging them in to see if they powered up and asked me what they were -he said they both came in together. Knowing that they could probably be sold on ebay for a few hundred bucks - it kind of felt like stealing...

author: free_electron
author_rank: Super Contributor
timestamp: July 21, 2013, 04:29:16 am
content: Cool. That merit thi g looks like an early flavor of the tenma/metex all in ones. Good catch !

author: c4757p
author_rank: Super Contributor
timestamp: July 21, 2013, 04:38:25 am
content: Ooh, nice. I'll have to check the local ones once in a while, wouldn't want to pass that up.My first scope was the 20 MHz version of that, actually GoldStar. It was a good one (well, besides the whole "20 MHz" thing...). I distinctly remember liking the feel of those lever switches and the push/pull switches on the knobs.

author: mtdoc
author_rank: Super Contributor
timestamp: July 21, 2013, 06:39:23 am
content: Quote from: c4757p on July 21, 2013, 04:38:25 amYeah, I know what you mean, they do have a cool feel to them. We'll see how well they hold up to a 7 year old's repetitive action....
Fluke 8840A Calibration - Page 1
Forum section: electronics / testgear

author: Anson
author_rank: Regular Contributor
timestamp: July 19, 2013, 10:52:45 pm
content: I recently got a Fluke 8840A off EBAY for $45 it was listed as "Desktop Meter". So I was very fortunate. I would like to have it "calibrated" or verified that the measurements are good or atleast know how far off they are. I didn't want to spend more than I paid for it. I have seen the DMM Check Plus and considered getting one to verify my meter and others. Is this a viable option? I'm just a hobbyist I don't need perfect. I just need to know my meter is somewhat accurate. Or would sending it in atleast once to be professionally calibrated still be warranted.

author: synapsis
author_rank: Regular Contributor
timestamp: July 19, 2013, 11:26:53 pm
content: I just picked up a DMM Check and am happy with it. I can use it on multiple devices, and if you pay shipping he'll recalibrate it for free for two years.

author: dr.diesel
author_rank: Super Contributor
timestamp: July 20, 2013, 12:00:00 am
content: Or list your State/City, there are many of us with proper equipment, we'd be happy to meet up with you and compare.

author: Anson
author_rank: Regular Contributor
timestamp: July 20, 2013, 12:17:10 am
content: Quote from: dr.diesel on July 20, 2013, 12:00:00 amWell I live in Florida but not near a real city. I live just outside a small town called Fort White. It's basically nowhere/hicksville but I like it. If someone were within an hour drive of me I could justify it.

author: dr.diesel
author_rank: Super Contributor
timestamp: July 20, 2013, 08:46:19 am
content: My wife just left for Ocala this morning!Hopefully somebody will pipe up here and be able to help out, there is likely equipment close by.
Micronta Pocket Multimeter teardown - Page 1
Forum section: electronics / testgear

author: Robomeds
author_rank: Frequent Contributor
timestamp: July 19, 2013, 05:50:47 am
content: Not much to this meter other than some sentimental value. This was my first meter and bought new back in the day. I think it was the cheapest or tied for cheapest meter Radio Shack sold. The competing option was a larger sized meter with manual ranging and likely amp testing. I went with auto ranging and size. In the end I don’t know that I regretted the choice. This was my only meter for perhaps 10 years. When I finally got a “real” meter I think it was the short test leads that did this one in.Though small, I always liked this meter. The auto ranging never seemed slow but that’s likely because it has only a few ranges. Slow auto ranging seems to normally bother me on ohms readings. 1 Mohm is the largest this thing will do. I believe it only has 4 ranges (1000 k, 199.9k, 1999, 199.9). Regardless in about 2 seconds it has a reading. The continuity is latched but not that quick and certainly not loud. The accuracy after all these years seems to basically agree with my Fluke 87 with in a count or two.Too bad it doesn’t have auto off… killed more than a set of batteries that way.So what’s inside?Well not much. There is a folded bit of foil as shielding. The batteries are a pair of 1.5V coin cells. Interestingly, they are not wired in parallel or series but each goes into the electronics its own way. The safety circuit is minimal to say the least. Then again this is a 400V max with no CAT rating meter. I don’t know if CAT ratings were common when this was a new meter. Either way it seems a PTC and perhaps a few diodes are it for safety. Not much to it… just like this review.

author: retiredcaps
author_rank: Super Contributor
timestamp: July 19, 2013, 05:58:12 am
content: Thanks for another teardown and review into your collection.There are 2 or 3 other 99 cent multimeters with reasonable shipping that may get no bids ready to expire in the next 24 hours or so.
Oscilloscope Memory Depth - Page 1
Forum section: electronics / testgear

author: echen1024
author_rank: Super Contributor
timestamp: July 18, 2013, 07:27:03 pm
content: Hi all,I am looking for a good scope for my general electrical tinkering, which mainly involves digital electronics communicating over I2C, UART, and SPI. Recently, I have been in need of an oscilloscope. Do you think a Tek TDS1002B or TDS220 with a 2.5k memory depth will be enough to capture the whole of the transmission? I am mainly looking at Tek scopes, since I almost have an attachment to them, due to my 465 as my 9th birthday gift that started my interest in electronics, but brands such as Rigol, Atten, and HP will do. Please recommend me a few models, and my budget is not to go over $500.Thanks.

author: Hydrawerk
author_rank: Super Contributor
timestamp: July 18, 2013, 07:35:48 pm
content: Quote from: echen1024 on July 18, 2013, 07:27:03 pm2.5kbytes is too small memory. Well, Tektronix was the first digital scope I ever saw, i liked it. But nowadays Tektronix makes no scopes that are bang per buck. With 500USD i would buy a Rigol or Siglent... Or collect more money and choose Rigol DS2000 series or maybe Agilent DSOX2000 series...

author: echen1024
author_rank: Super Contributor
timestamp: July 18, 2013, 07:58:25 pm
content: Ok. Thank you. I will probably just buy the lowest priced Rigol DS1052E and hack it up to the 100MHz standard.Thanks

author: mike1305
author_rank: Contributor
timestamp: July 18, 2013, 10:56:40 pm
content: Best way to determine the amount of memory you need is to work backwards.Let's say you're measuring a 100kHz SPI bus. You'll need to be sampling around 400,000 Samples/sec (4x bandwidth is a fine approximation). Then ask yourself how much time you need to capture. If you need 4ms to capture your longest SPI transaction, then you'll need at least 1,600 points of memory. = [sample rate] x [capture time]mike
Acquiring BK Manuals that aren't on the site - Page 1
Forum section: electronics / testgear

author: Stonent
author_rank: Super Contributor
timestamp: July 18, 2013, 04:47:01 pm
content: Most manuals are here:http://www.bkprecision.com/support/downloads/manuals/en.htmlHowever I was looking at an Ebay scope that was a clone of a BK scope that wasn't listed on their website, so I filled out the form here:http://www.bkprecision.com/support/request.htmlAnd they e-mailed me a PDF of the manual, parts list and schematic. They mentioned that they no longer stock replacement parts for that model and offered to give me a trade-up credit for the 30 year old scope.
DS2000 Series Scope Self Calibration - Page 1
Forum section: electronics / testgear

author: bluesmoke
author_rank: Contributor
timestamp: July 23, 2013, 01:13:02 am
content: Whats the correct procedure to do a self calibration on a DS2000 series scope, apart from letting it warm up 30 minutes or so?What is confusing me is that in the manual it explains connecting the back trigger out connector to the 2 channels and trigger in but when you go to calibrate it says to make sure no signals are on the input channels!

author: ddavidebor
author_rank: Super Contributor
timestamp: July 23, 2013, 03:06:41 am
content: No signal is right
Use AWG to generate PAL video pattern? - Page 1
Forum section: electronics / testgear

author: Chalky
author_rank: Regular Contributor
timestamp: July 17, 2013, 12:16:15 pm
content: Is there an AWG out there that would let me easily generate a simple, static, PAL video signal? Something like the Rigol DG4062?When I say easy, I guess I'm thinking of 1 of 2 methods:1. A 'TV PAL' built-in waveform. Great!2. I understand exactly what my video signal should look like, so I daresay I could construct the pattern and produce a CSV/XML/whatever data file of the signal I want - the AWG would need some mechanism for importing a pattern from file.3. Anything else!Any ideas? Cheers!

author: jpb
author_rank: Super Contributor
timestamp: July 17, 2013, 12:34:10 pm
content: Test and measure :http://www.test-measure.co.uk/list.htmlare selling a Tektronix TSG131A PAL Signal Generator but it is rather pricier than the DG4062 (though not by that much) and I guess the shipping to Australia would be prohibitive.

author: Chalky
author_rank: Regular Contributor
timestamp: July 17, 2013, 12:40:01 pm
content: That unit looks good, but am hoping to find an AWG that does this, to avoid investing in both AWG and dedicated video signal generator, if I can. Budget is tight.

author: jpb
author_rank: Super Contributor
timestamp: July 17, 2013, 01:44:04 pm
content: The Rigol scope demo board will produce a PAL signal:http://www.batronix.com/pdf/Rigol/UserGuide/DS6000DemoBoard_UserGuide_EN.pdfBut I don't know if that would be flexible enough for you.

author: nctnico
author_rank: Super Contributor
timestamp: July 17, 2013, 06:48:21 pm
content: IMHO you should be able to buy a PAL videogenerator for peanuts. Repair shops are dumping them all the time. Look on Ebay and try to make a deal on a 'buy it now' item. I recently got some equipment for half the asking price but OTOH I did buy the entire lot

author: KedasProbe
author_rank: Frequent Contributor
timestamp: July 18, 2013, 07:58:15 am
content: Any old video recorder/player has PAL output I assume (if you are not picky on the signal)Maybe some HDMI to PAL can help you (just make HDMI from PC)

author: jpb
author_rank: Super Contributor
timestamp: July 18, 2013, 08:33:39 am
content: On similar lines, a lot of the old home computers such as the BBC model B produce PAL signals. They can still be picked up cheaply on e-bay. I was offered a BBC-B for free recently but decided I didn't have house-room for it.Using a home computer you can set up lots of fixed patterns using BASIC.There are several model Bs on the UK e-bay where they seem to be going for under £50.here is the service manualhttp://acorn.chriswhy.co.uk/docs/Acorn/Manuals/Acorn_BBCSMOct85_Sec1.pdf
Changing the Voltage on Anritsu ME538L Transmitter/Receiver? - Page 1
Forum section: electronics / testgear

author: Testwall
author_rank: Newbie
timestamp: July 11, 2013, 09:56:19 am
content: Hi,I have two Anritsu ME538L transmitter/receiver test sets which I need to change the voltage from US to EU (115-230V). Has anyone any experience in this or be able to supply a schematic diagram for the transformer ( I have attached a picture of the transformer in question!)?Any help would be greatly appreciated.Thanks,T.

author: SeanB
author_rank: Super Contributor
timestamp: July 11, 2013, 04:31:42 pm
content: Need a photo of the input side as well, and a photo of the mains wiring to it and the power switch as well, probably a simple photo showing it in the case as well to see wiring layout. It looks like it can be changed to 230V operation though.

author: Testwall
author_rank: Newbie
timestamp: July 17, 2013, 03:29:23 pm
content: Thanks Sean,I managed to get the original schematics direct from Anritsu.
Tektronix custom ic compatibility - Page 1
Forum section: electronics / testgear

author: Clod
author_rank: Newbie
timestamp: July 17, 2013, 02:36:47 pm
content: I bought an old 475 oscilloscope and I noticed that same custom ic (155-0078-xx, 155-0085-xx) is used several times with different selections (00, 01, 05 ...), does anyone know if a lower selection is replaceable with greter selection?Thanks
Acute TL2236B vs Zeroplus LAP-C322000 logic analyzers - Page 1
Forum section: electronics / testgear

author: im2geek4you
author_rank: Newbie
timestamp: July 15, 2013, 11:30:25 pm
content: Hello all,So I'm thinking about buying an LA that does protocol decoding with the largest number of channels and highest sampling rate. The Acute TL2236B sold by Batronix seemed a good candidate. However I did a look around in this forum and Acute brand is almost never mentioned. I found Zeroplus mentioned in another thread and the LAP-C322000 seems to be at the same level than the Acute.Does anyone knows anything about these 2 logic analyzers. Which one is the best "bang for the buck"?Perhaps someone owns one?Regards

author: nctnico
author_rank: Super Contributor
timestamp: July 15, 2013, 11:46:38 pm
content: I like the Acute because it has a much higher sampling rate compared to the Zeroplus. OTOH don't expect to use either on high speed signals. The probes are not up to such a task. The high samplerate only provides a better time resolution.What I don't like about both is that they specify the total amount of memory which is a bit misleading. You will want the model with the largest memory.
Fan model of HP Agilent E3644A? - Page 1
Forum section: electronics / testgear

author: mimmus78
author_rank: Unknown
timestamp: July 15, 2013, 03:52:47 pm
content: I have repaired a E3644A with a problem to the circuit controlling fan speed (found a bad opamp).I think during previous repair attempt they have replaced the fan with a wrong model because now, even with output off it is very noisier (actually noisier than my rigol 1052e)Anyone know if the original fan for this power supply is the F6025E12B?
BK Precision 4017B DDS Function Generator - Page 1
Forum section: electronics / testgear

author: elliott
author_rank: Regular Contributor
timestamp: July 10, 2013, 06:40:15 am
content: I just put a best offer on a BK 4017B function generator on eBay and got it. It seems like a good general purpose function generator, I don't need much, just more than the old home-built opamp generator can give. I had been bidding on some non-DDS function generators, even the older BK 4017, but this wasn't going for that much more.Does anyone have any experience with these? Not a whole lot of information out there on them.

author: elliott
author_rank: Regular Contributor
timestamp: July 13, 2013, 07:22:25 am
content: I just got the function generator today and the 50 ohm output fuse is blown, it is a little SMD fuse with the marking F250 on it, which I assume is just voltage and gives me no useful information. I can't find a service manual for it, but I did email BK and asked if they could tell me the value of the fuses.If BK doesn't respond, I'm going to have to determine a replacement for myself, would I be wrong in thinking that 0.2A would be appropriate since the output is 10V and 50 ohms?

author: david77
author_rank: Frequent Contributor
timestamp: July 13, 2013, 07:39:28 am
content: F250 means Fast blow 250mA, so your assumption is more or less correct.

author: elliott
author_rank: Regular Contributor
timestamp: July 13, 2013, 08:20:55 am
content: Quote from: david77 on July 13, 2013, 07:39:28 amMakes sense, I was just assuming it was voltage because 250V is very common in fuses. I was also assuming the outputs would be fused differently, though that is based on no prior experience.I need to find some kind of cheat sheet for SMD markings, I'm so used to through hole.Thanks, now I just need to measure the thing so I get the right size.

author: ve7xen
author_rank: Super Contributor
timestamp: July 13, 2013, 09:20:45 am
content: Probably a good idea to get replacement devices for the output stage at the same time. Chances are pretty good the fuse didn't save them...

author: elliott
author_rank: Regular Contributor
timestamp: July 13, 2013, 09:30:03 am
content: Quote from: ve7xen on July 13, 2013, 09:20:45 amIt appears to be outputting fine up to the fuse, just not through it, I didn't put a load on it though.
B&K Precision 889B vs. Instek LCR-821 ...? LCR/ESR Bench Meter war. - Page 1
Forum section: electronics / testgear

author: Unknown
author_rank: Unknown
timestamp: July 11, 2013, 05:13:47 pm
content: http://www.testequity.com/products/3058/Vs.http://www.testequity.com/products/1060/200khz, rs232 included, Z/Phase (LCR-821 only).?

author: Unknown
author_rank: Unknown
timestamp: July 14, 2013, 04:43:35 pm
content: Is the DC capacitor offset/Bias input of the Instek worth $1000usd. more than BK ?is the variable frequency worth $1000usd. more ?someone here has them?

author: The Electrician
author_rank: Frequent Contributor
timestamp: July 14, 2013, 10:16:37 pm
content: The B&K can only measure at 6 discrete frequencies and 3 voltage levels.The Instek can measure at 504 frequencies from 12 Hz to 200 kHz and at any voltage between 5 mV to 1.275 volts with 5 mV steps. This is very much nicer than the B&K.However, I saw a new Chinese LCR meter made by Applent:http://www.applent.com/products/detail.aspx?familyid=lcr&model=AT2816AIt can measure at any frequency between 50 Hz and 200 kHz with 1 millihertz resolution!!! It can set the excitation level to anything between 10 mV and 2 volts with 10 mV steps. And, it's available on eBay:http://www.ebay.com/itm/NEW-Hot-Product-AT2816A-High-Frequency-50Hz-200kHz-Digital-3-5-LCR-Meter-Tester-/121140175088?pt=LH_DefaultDomain_0&hash=item1c348460f0for $1823, considerably less than the $2560 for the Instek.
Analog Discovery in retail stores in the US ? - Page 1
Forum section: electronics / testgear

author: JeanF
author_rank: Regular Contributor
timestamp: July 13, 2013, 09:54:44 pm
content: Hello,I'll be travelling a bit in the US later this July, and I was wondering if this... device (safe name, so people who claim it's not a scope won't be hurt !) could be possibly be sold in a store. I'll land in NY and then drive my way to West Coast with various stops...This thing is available where I live at 200€, wich is in my opinion too expensive when it compares with Rigol prices for a budget (real) scope. The goal is to find it cheaper in the US ! any clue ? Thanks !If you own one (in good working condition !) and you would like to resell it, MP me where you live and your price.CheersJF

author: TerminalJack505
author_rank: Super Contributor
timestamp: July 13, 2013, 10:44:20 pm
content: I have an Analog Discovery and I love it. I was fortunate enough to get one at Newark.com for $99.I don't know if you will be able to find one in stores or not. Even if you do, I'm sure it will be more expensive than ordering one directly from Digilent. Digilent sells them directly for $200 so if you are visiting friends or family in then states then you might have it shipped to them.If you do order from Digilent then you might want to get aBNC adapter boardtoo. The flying leads don't work out so well for low voltage levels since they'll pick up a lot of noise. The BNC adapter board will let you use proper scope probes and reduce the noise.You can use 10x probes simply by creating a math channel. Channel 1 * 10, will give the proper voltage readings, for example. I don't think you can trigger off of a math channel but you can still trigger off of the attenuated signal. The signal doesn't even have to be displayed to trigger off of it.Digilent also sells cheap probes. I bought a pair and they do work but you might get those elsewhere. They don't come with a ground spring and I couldn't quite compensate one of them for a particular channel. I just swapped channels, though, to fix that.

author: Bored@Work
author_rank: Super Contributor
timestamp: July 14, 2013, 09:10:10 am
content: Seriously, why do you want to give this nationalistic assholes your money? Their pricing policy makes it absolutely clear that Analog Devices and Digilent prefers US students only as customers.

author: mikeselectricstuff
author_rank: Super Contributor
timestamp: July 14, 2013, 09:16:12 am
content: Quote from: Bored@Work on July 14, 2013, 09:10:10 am..so the answer is to find a hard-up US student to resell one to you at a small profit
digital storage oscillioscope - Page 1
Forum section: electronics / testgear

author: ant17
author_rank: Regular Contributor
timestamp: July 13, 2013, 12:18:36 am
content: hi guys i am wanting to upgrade to a digital oscilloscope. I intend to us it for analog electronics and Rf electronics the scope i use now is about 1975 model bwd.I don't really know how to select the best option for me. I don't want to pay more than 1000 dollars if someone could suggest a good one they have had experience with or one that think might suit.I know bandwidth is important but i was wondering how do some people measure around the 2ghz frequency when attempting to fix a wireless router its just a little side question thanks

author: Unknown
author_rank: Unknown
timestamp: July 13, 2013, 03:34:39 am
content: Try reading one of the dozens of DSO topics on this forum or watching some of the various video reviews Dave did. Given your requirements, I'm going to suggest a relatively cheap Rigol DS1102E. No point in spending money if you have no idea about what you need.For RF signals like 2.4 GHz you would typically use a spectrum analyzer with much more than 2.4 GHz bandwidth, especially for design. For troubleshooting it's probably enough to check for the presence of the signal, there's not much to tune in your typical access point. A Wifi signal wouldn't be very interesting on a scope, mostly sine-like.

author: ant17
author_rank: Regular Contributor
timestamp: July 13, 2013, 05:37:33 am
content: thanks
So what exactly does Ultra Sigma do (Rigol) ? - Page 1
Forum section: electronics / testgear

author: alank2
author_rank: Super Contributor
timestamp: July 09, 2013, 05:24:24 pm
content: Hi,For a 350Mb+ download am I understanding it properly to be a simple SCPI command sender? Does it do something else?Is there a utility similar to the old Ultra Scope that Rigol produces? (I know about the RUU which I am also checking out).

author: eastonwolfs
author_rank: Contributor
timestamp: July 25, 2013, 12:44:54 pm
content: I would like to know this too... Anyone know?

author: gierig
author_rank: Newbie
timestamp: July 26, 2013, 07:27:06 am
content: One first instance it provide a "Rigol Own" interface to thair Products. Think there are some Application for ther DSA where you cancontroll you device.

author: eastonwolfs
author_rank: Contributor
timestamp: July 26, 2013, 07:42:02 am
content: Thanks for the reply gierig.It seems strange that Rigol do not produce an updated version of Ultrawave for the DS2000 series. After all, they did supply software for the less capable 1000 series. Perhaps they now rely on their customers to produce better quality software, such as marmad and RUU?

author: Bored@Work
author_rank: Super Contributor
timestamp: July 26, 2013, 03:17:41 pm
content: Quote from: eastonwolfs on July 26, 2013, 07:42:02 amRigol never cared about their software. E.g. the DG1022 came in two hardware versions (and these days there are another two, the U and A versions). The first hardware version was released around end of 2008. Two years after Vista was released and Windows 7 was just around the corner. Yet they delivered only some rubbish XP software and never upgraded it. The software they now offer only works for the second (and maybe later) hardware versions.
Hitachi V212 Oscilloscope - Page 1
Forum section: electronics / testgear

author: dadams
author_rank: Newbie
timestamp: July 11, 2013, 09:57:22 pm
content: Hello to all!I just acquired one of these oscilloscopes and while channel 1 works great (lower signal in the video), there is one issue with channel 2 (upper signal in the video) that I am trying to figure out. The vertical position of channel 2 stays fixed between about 1 division on the screen. Changing the vertical position knob for channel 2 moves it up and down within the 1 division area. When I change the Volts/Div, the signal seems to change proportionally, but still stays only within that 1 division area.I'm thinking it may be in the channel 2 pre-amp section, but I am not sure since this is the first analog oscilloscope I have used. I just don't want to go probing all around with high voltages present in there. Trying to stay safe and alive, you know. The video shows what it does. The sound is horrible and super quiet and I sound really stupid because I had to talk loud to compensate for the crappy built in mic. But, if anyone has any ideas on what sections I should start looking at or what things to look for, I would appreciate it! Thanks!Drew
Identifying and testing unknown antennas - Page 1
Forum section: electronics / testgear

author: Shaw
author_rank: Newbie
timestamp: July 11, 2013, 02:04:43 am
content: Hi all,I've got a bunch of rubber-duck antennas at home in a box, I know some are 900Mhz and some are 2.4Ghz ones. Of course they all look the same which is annoying. Is there any simple way for me to test these?I don't have a full electronics lab, but I do have a Rigol 100Mhz scope and multimeter... I don't have a signal generator or spectrum analyzer, which I suspect are the two pieces of required kit.Any suggestions on a quick and easy way to identify these would be great.

author: WarSim
author_rank: Frequent Contributor
timestamp: July 11, 2013, 02:52:37 am
content: Without a signal generator or network analyzer, I can't think of anyway at the moment.

author: Rasz
author_rank: Super Contributor
timestamp: July 11, 2013, 03:00:26 am
content: http://pe2er.nl/wifiswr/or just get a wifi card and try all the antennas checking signal strength of a known ap

author: vk6zgo
author_rank: Super Contributor
timestamp: July 11, 2013, 03:22:30 am
content: Quote from: Rasz on July 11, 2013, 03:00:26 amNice project,but being "rough as guts",I would go with your second suggestion!

author: WarSim
author_rank: Frequent Contributor
timestamp: July 11, 2013, 03:26:41 am
content: I agree the second suggestion is much better than my no idea option.

author: olsenn
author_rank: Frequent Contributor
timestamp: July 11, 2013, 04:02:30 pm
content: What are you trying to measure? SWR can be measured with a spectrum analyzer and a bridge or coupler. impedance can be measured with a multimeter or LCR meter, but it's safer if you measure this at the frequency you're operating at. More advanced measurements really call for a network analyzer and more specific equipment

author: babysitter
author_rank: Frequent Contributor
timestamp: July 11, 2013, 07:34:58 pm
content: Look out for the local ham radio club. You might find that certain guy that loves to do exactly that, there.I second the method of hooking it up to a Wifi card, and try to get the best estimation of field strength you can get -with windows, netstumbler is your friend and wl under linux, I think.Be careful when tightening the connectors.
Rigol ds1052e timebase adjust - Page 1
Forum section: electronics / testgear

author: ddavidebor
author_rank: Super Contributor
timestamp: July 10, 2013, 07:05:56 pm
content: Hi guys.I use very much this little scope and his internal frequency counter... Very handyBut, it's 15lsd off...It's possible to adjust the rigol timebase without break the warranty?
How to send a setup using :SYSTem:SETup on Rigol... - Page 1
Forum section: electronics / testgear

author: alank2
author_rank: Super Contributor
timestamp: July 10, 2013, 04:06:36 am
content: Hi,Does anyone know how to format the setup data after this command?:SYSTem:SETup <setup_data>I've tried::SYSTem:SETup\n#9000002493<data>:SYSTem:SETup #9000002493<data>:SYSTem:SETup #9000002493<data>\nMaybe I did something wrong - does someone know?

author: ve7xen
author_rank: Super Contributor
timestamp: July 10, 2013, 04:17:05 am
content: I assume in the same way :SYSTem:SETup? returns the data, which seems to work just feeding it back to the scope verbatim.That format is::SYSTem:SETup #9000002579<data>\nBeware that you're actually writing the bytes as they came from the scope though, as many mechanisms for doing this might be doing conversion to other character sets etc.In other words, this code works:Code:config = rigol.ask_raw(":SYSTem:SETup?")rigol.write_raw(":SYST:SET " + config)

author: alank2
author_rank: Super Contributor
timestamp: July 10, 2013, 12:24:06 pm
content: Thanks - your method worked!
Schematic for Kikusui PAL 35-10 Power Supply - Page 1
Forum section: electronics / testgear

author: Marc M.
author_rank: Regular Contributor
timestamp: July 10, 2013, 04:42:04 am
content: I picked up a couple of DOA Kikusui PAL 35-10 power supplies off of Fleabay. Unfortunately, Kikusui doesn't supply any service information/schematics on their website, just the operating manual. Also, my Google & Yahoo searches came up with nothing. Does anyone here have have anything on these supplies?Any help is greatly apprecieated -
B&K Precision 560 IC tester - Page 1
Forum section: electronics / testgear

author: caius
author_rank: Regular Contributor
timestamp: July 12, 2013, 02:56:07 pm
content: Hi all,could anyone tell me more about this kind of device for testing ICs out and in-circuit:http://bee.mif.pg.gda.pl/ciasteczkowypotwor/B&K/bk560%20instruction%20manual.pdfThanks
RIGOL DS2202 measurement issue - Page 1
Forum section: electronics / testgear

author: MaxwellsSilverHammer
author_rank: Newbie
timestamp: July 09, 2013, 07:27:43 pm
content: I have been using this RIGOL DS2202 200MHz scope and have had a major FAIL!! When trying to measure both frequency and Vpp at the same time I noticed that the scope only measures one value correctly and the other is wrong. For example I was trying to measure a swept sine wave from 200kHz to around 800kHz and the Vpp should be around 4 Vpp but the voltage displayed incorrectly (kilovolts) but frequency was correct. If I select only one value in the measure sub menu the value is correct, but as soon as I add two or more values in the measure menu, for example frequency and Vpp one of the values do not display correctly. Is this a firmware issue or is my scope a lemon? The measure menu allows for the reading of 5 values simultaneously but as soon as I add more than one the other values display incorrectly.Just ridiculous, I spent over $2000 on this scope, the Agilent I use can do this with no problem. WOW this just seems to be a huge FAIL on RIGOL's part. I think I will never buy another RiGOL product at this point...

author: Galaxyrise
author_rank: Frequent Contributor
timestamp: July 09, 2013, 07:45:36 pm
content: Have a look at thelist of known firmware bugsat the start of the giant DS2000 thread. That particular one is bug #13, and it's restricted to firmware v.01.00.00.03Upgrading to 01.01.00.02 should fix it, and you can get the firmware from that same post.

author: MaxwellsSilverHammer
author_rank: Newbie
timestamp: July 09, 2013, 07:50:51 pm
content: Quote from: Galaxyrise on July 09, 2013, 07:45:36 pmI got the latest firmware from the RIGOL APP Engineer and my scope is just a huge Lemon now. This seems really unacceptable at this point after spending over $2000 on the scope :-(

author: Galaxyrise
author_rank: Frequent Contributor
timestamp: July 09, 2013, 07:59:12 pm
content: I'm surprised this isn't listed as one of the bugs in the list. Follow the instructions from the post I linked before:Quote from: marmad on October 30, 2012, 02:14:25 pm

author: Galaxyrise
author_rank: Frequent Contributor
timestamp: July 09, 2013, 08:02:23 pm
content: Also, make sure that the firmware you got is 01.01.00.02, as the previous version (01.00.00.03) is the one with the bug you're complaining about. Check the aforementioned post for how to get your full firmware version

author: MaxwellsSilverHammer
author_rank: Newbie
timestamp: July 09, 2013, 08:12:54 pm
content: The AP engineer sent me the wrong firmware update originally. Finally I was sent the correct firmware. Not very professional on Rigol's part dealing with a business looking to procure more test gear, anyhow, it's fixed now. Cheers!!
Comark Digital Thermometer 5000 (1970s thermometer) - Page 1
Forum section: electronics / testgear

author: TheEPROM9
author_rank: Frequent Contributor
timestamp: May 07, 2013, 07:12:02 pm
content: This little beauty was found in the engineering departments WEEE bin, that bin supply's so many nice things =-)The company Comark are still going but sadly there is no information what so ever on this thermometer, I believe it is thermocouple as whats left of the wires seems to work but it is out of cal quite badly, there may also be other problems. Any user or service manuals would be fantastic and allow for such calibrating.I will have to past the pictures separately due to file size.

author: TheEPROM9
author_rank: Frequent Contributor
timestamp: May 07, 2013, 07:13:43 pm
content: More Pics

author: TheEPROM9
author_rank: Frequent Contributor
timestamp: May 07, 2013, 07:14:44 pm
content: The rest of the pics =-)

author: SeanB
author_rank: Super Contributor
timestamp: May 08, 2013, 04:14:52 pm
content: Nice type K multiple input indicator. Probably all that it needs is a short of copper wire across each input, a clean up of the contacts on the switch at the rear and then checking that all channels display the same temp, which should be room temperature +-5C. If so then nothing needs doing really.

author: TheEPROM9
author_rank: Frequent Contributor
timestamp: May 09, 2013, 03:30:17 pm
content: You are right, after being in a skip it could do with some maintenance. I do need to find it a proper probe and find the cal pots,then it should be happy.

author: TerminalJack505
author_rank: Super Contributor
timestamp: May 09, 2013, 03:50:14 pm
content: With all that circuitry I kind of expected something more than just "027".Maybe "027.123". Or, perhaps, "Sorry, Dave. I can't let you do that."

author: TheEPROM9
author_rank: Frequent Contributor
timestamp: May 09, 2013, 05:00:07 pm
content: Quote from: TerminalJack505 on May 09, 2013, 03:50:14 pmIt is an excellent example of integration in technology.Hell my old laptop made in 2006 is less powerful than the most powerful mobile phones. Remarkable development if you ask me.However the old stuff just had the cool that the modern stuff does not.

author: TheEPROM9
author_rank: Frequent Contributor
timestamp: July 08, 2013, 08:24:06 pm
content: Quote from: SeanB on May 08, 2013, 04:14:52 pmIndeed you seem to have been correct, used contact cleaner on all the connectors and pots, seems to be much more stable saying 23*C. Doing a long running test =-)
Correct method for triggering on Rigol 1102e - Page 1
Forum section: electronics / testgear

author: Shaw
author_rank: Newbie
timestamp: July 08, 2013, 12:21:03 pm
content: Hi, I just bough a Rigol 1102e scope and have been experimenting capturing traces off every piece of electronics I can get my hands on. One thing which has puzzled me is with my radio control transmitter which has a digital PPM output into the actual transmitter module. Basically it sends a short burst of 10 pulses at +5v followed by a 0v "gap" and another burst of 10 pulses. (it's a Hitec Aurora 9 for those who are interested)My problem is how to get the scope to trigger on the first low->high edge of each block rather than randomly on some low->high edge. I am trying to get it so that I can see an entire block of the 10 channel PPM encoded transmission on the screen at the same time so that I can see what happens when I change the positions of the sticks on my controller.I've tried searching on google but I haven't had much luck, probably just due to lack of the right search terms.Thanks in advance

author: alank2
author_rank: Super Contributor
timestamp: July 08, 2013, 12:28:25 pm
content: There is a holdoff option in the trigger setup that you can make larger that might help.

author: Unknown
author_rank: Unknown
timestamp: July 08, 2013, 12:28:57 pm
content: Search for trigger hold-off. Should work fine assuming the length of the burst of 10 pulses is constant. I think Dave even did a video tutorial on trigger hold-off.

author: Shaw
author_rank: Newbie
timestamp: July 08, 2013, 12:49:44 pm
content: "trigger hold-off eevblog" - perfect!Thanks for the tip.Half the battle is knowing just the right keywords to use
Terminals on test equipment - Page 1
Forum section: electronics / testgear

author: Shas-O
author_rank: Contributor
timestamp: July 08, 2013, 07:24:19 am
content: hi DaveDid I see that you have a HP 3457?We just purchased the Agilent 3458, which I think is a later model, and found that the current posts were loose.This affected readings if the leads were moved.Seems the fuse holder is built into the post, dumb asses.Is this the same on the 3457?Derek
Tektronic 2430A - Page 1
Forum section: electronics / testgear

author: TheKraken
author_rank: Newbie
timestamp: July 07, 2013, 12:47:50 am
content: I recently found someone that would part with a tektronic 2430A oscilloscope. I was wondering what the general consensus was on the model, the price is right so I may buy it in either case but a heads up on what i might be getting into with it would be appreciated.Thanks!

author: nctnico
author_rank: Super Contributor
timestamp: July 07, 2013, 12:51:57 am
content: The storage memory is only 1kpts so way too short for debugging I2C and SPI busses.

author: dfmischler
author_rank: Frequent Contributor
timestamp: July 07, 2013, 02:06:10 am
content: My first digital storage scope was a 2430A. It had a nice feel to it, but as nctnico said, the trace memory is very shallow. I also found the maximum sample rate of 100 MS/s to be too slow. Even though the front end is rated at 150 MHz, the low sample rate essentially makes the single-shot bandwidth about 40 MHz max, so you can barely capture a non-repetitive 8 MHz square wave.If you decide that you can live with the limitations make sure you see that all tests pass on the self-test screen and verify all input channels operate before spending anything on this scope. It is also rumored that if the internal battery dies (and it is more than 20 years old) then you will not be able to calibrate it to return it to service without some serious equipment.

author: c4757p
author_rank: Super Contributor
timestamp: July 07, 2013, 02:07:17 am
content: Personally, I'd avoid any pre-TDS series digital Tektronix scopes, and many early TDS series scopes as well.

author: TheKraken
author_rank: Newbie
timestamp: July 07, 2013, 03:55:36 am
content: Thanks guys. I guess the guy already sold it. But was only asking 25 bucks so i figured it was a great price to get my first Oscilloscope. Too bad though. Ill have to keep looking.

author: c4757p
author_rank: Super Contributor
timestamp: July 07, 2013, 03:56:20 am
content: $25? Damn, I wish you actually included the number. Hell, if it turns on, buy it, at that price! Too bad it's gone.
GDM-8035 DVM info wanted - Page 1
Forum section: electronics / testgear

author: harveyradar
author_rank: Contributor
timestamp: July 07, 2013, 12:53:29 am
content: I am seeking a service manual for a Goodwill GDM-8035 bench digital multimeter. This model was made in 1980 by Good Will Instrument Co., Ltd. GW has unfortunately informed me "The GDM-8035 is phased out almost 20years ago. We do not have the related documents on hand. " So any help would be appreciated.Thanks in advanceHarvey.
dc surface voltmer eev #247 - Page 1
Forum section: electronics / testgear

author: michi42
author_rank: Newbie
timestamp: July 06, 2013, 02:16:31 pm
content: Hi,i rememered eev #247 at 7:40 dave plays around with a "voltmeter"i wonder how this thing works.It's from alpha-labs afaik.I thougt it would be impossible to mesaure electrostatic field strength without using a rotary voltmeter.Second principle that comes in mind is force applied by the e-field to a charged probe.But this seems to work differently. Do they use a charge amplifier like in piezo sensors?
Is there a Logic Analyzer with an SDK for proprietary Protocol encoding ? - Page 1
Forum section: electronics / testgear

author: roli_bark
author_rank: Regular Contributor
timestamp: July 05, 2013, 05:45:47 am
content: Is there in the market a Logic Analyzer with an optional SDKto enable the user develop a proprietary Serial Protocol encoding ?

author: Carrington
author_rank: Super Contributor
timestamp: July 05, 2013, 06:26:07 am
content: See this:http://www.asix.net/tools/dbg_omega.htmhttp://www.asix.net/tools/download/analyzers/sigmap02_plugin_developer_manual.pdfSource codes of some plugins are released under GPL, thus users are free to modify or create plugins. (Page 12, datasheet)Cheers

author: nctnico
author_rank: Super Contributor
timestamp: July 05, 2013, 07:31:49 am
content: Look at the Tektronix TLA700 series and my serial decoding software:https://forum.sparkfun.com/viewtopic.php?f=14&t=30757&p=136729#p136729

author: Unknown
author_rank: Unknown
timestamp: July 05, 2013, 07:49:13 am
content: Plenty of them will. For example the Usbee (with optional software), Saleae, Zeroplus, DigiView and of course the OLS logic analyzers all support the development of custom decoders.
Uni-T 61E Fuses - Page 1
Forum section: electronics / testgear

author: Bryan
author_rank: Frequent Contributor
timestamp: July 04, 2013, 08:08:25 am
content: Anybody know what the replacement fuses for this meter are or a better replacement. Paper manual was in Chinese, and the online manual statesA mA range: F1, 1A H 240V, 6x25mm (CE)10A range: F2, 10A H 240V, 6x25 mm. (CE)I can not find fuses that are 6x25mm. Should they be Fast, Slow, Medium blow?Don't trust the rated CAT on the meter, so certainly won't use in anything about CAT2 so no point in sourcing out 1000v fuses

author: Wytnucls
author_rank: Super Contributor
timestamp: July 04, 2013, 08:45:48 am
content: Just put any fast blow 250V fuse that fits in there and you'll be fine or buy a few of the original ones on the internet.

author: Monkeh
author_rank: Super Contributor
timestamp: July 04, 2013, 05:45:16 pm
content: It's written on the fuses: BS1362. They're easily found.

author: Unknown
author_rank: Unknown
timestamp: July 04, 2013, 06:02:11 pm
content: In the UK at least, but also in wherever Bryan is from (presumably the Antarctic). BS1363 plugs are not very common outside the UK, so I'm guessing the fuses might not be either.
Where to find rom data for fluke combiscope? - Page 1
Forum section: electronics / testgear

author: ddavidebor
author_rank: Super Contributor
timestamp: June 29, 2013, 08:50:34 pm
content: Hi, i've a fluke combiscope and it beeps continuously at power on.I think i need to re-program the rom, but i'm unable to find it in internet.Anyone knows wherto find it?

author: free_electron
author_rank: Super Contributor
timestamp: June 29, 2013, 09:12:46 pm
content: Which combiscope ? There's like 40 different ones...Roms dom't go bad very often. Those machines use old fashioned eprom.Id check for missing voltages first.Get the service manual. The beeps may mean something...

author: ddavidebor
author_rank: Super Contributor
timestamp: June 29, 2013, 09:29:27 pm
content: Power supply is ok, and service manual doesn't have a troubleshooting chart.It power on but nthing happens. Light on, but nothing on screen.

author: nctnico
author_rank: Super Contributor
timestamp: June 30, 2013, 12:13:57 pm
content: I'd start checking whether the CPU runs and what the address lines do. Problems like these won't get solved by just swapping components blindly. In the end you can swap all the components without any luck because there is an open trace somewhere on the PCB. Another thing to try is reseating all the socketed devices (=lifting the chips a bit from their sockets and push them down again) .

author: free_electron
author_rank: Super Contributor
timestamp: June 30, 2013, 01:52:24 pm
content: indeed, socket parts sometimes give trouble.

author: ddavidebor
author_rank: Super Contributor
timestamp: July 02, 2013, 05:39:22 am
content: Nope, nothing changed.The cpu sure run, or the buzzer will not work.Well, i will check the schematics but i'm pretty sure,

author: Unknown
author_rank: Unknown
timestamp: July 02, 2013, 05:50:45 am
content: Agree with free_electron. I think if the ROM were bad it wouldn't be constantly beeping. That's an error mode of some kind.

author: ddavidebor
author_rank: Super Contributor
timestamp: July 03, 2013, 02:06:58 pm
content: It has two firmware one from a mask rom, one from an eprom.The first with basic start up sequence, the second with operative system.

author: ddavidebor
author_rank: Super Contributor
timestamp: July 03, 2013, 02:07:29 pm
content: Quote from: nctnico on June 30, 2013, 12:13:57 pmWhat you mean by "what the address line do"?

author: nctnico
author_rank: Super Contributor
timestamp: July 03, 2013, 07:24:30 pm
content: See if they all toggle every now and then and have valid logic levels. An address line not toggling or having invalid logic levels is a tell tale sign there is a short or a chip is bad. The same goes for the data bus.

author: ddavidebor
author_rank: Super Contributor
timestamp: July 04, 2013, 11:40:23 am
content: Ok thanks!
SCPI app - Page 1
Forum section: electronics / testgear

author: Harvs
author_rank: Super Contributor
timestamp: July 04, 2013, 03:29:34 am
content: I've just uploaded an android appherefor doing basic commands on instruments. Let me know if there's anything else you'd like to see in it.I'm going to make a more specific one for the DS2000 aimed at tablets, but this one is just a generic command interface for quick tests if you don't have a laptop with the required software handy.

author: bluesmoke
author_rank: Contributor
timestamp: July 04, 2013, 05:36:28 am
content: Looks useful.. Thanks.
Dick-Smith Scope for sale in the US? - Page 1
Forum section: electronics / testgear

author: Stonent
author_rank: Super Contributor
timestamp: July 03, 2013, 09:22:09 am
content: Imported Dick?http://www.ebay.com/itm/Dick-Smith-Q-1240-Oscilloscope-/151074946030?pt=BI_Oscilloscopes&hash=item232cc4bbee

author: EV
author_rank: Frequent Contributor
timestamp: July 03, 2013, 11:28:54 am
content: Quote from: Stonent on July 03, 2013, 09:22:09 amLooks like Trio scope.

author: edavid
author_rank: Super Contributor
timestamp: July 03, 2013, 04:59:44 pm
content: They had stores in the US for a few years:http://en.wikipedia.org/wiki/Dick_Smith_%28retailer%29#United_StatesAlso, made in Korea, so... Goldstar.

author: c4757p
author_rank: Super Contributor
timestamp: July 03, 2013, 05:03:40 pm
content: Quote from: edavid on July 03, 2013, 04:59:44 pmThere was a piece of protoboard at the electronics shop near me a few months ago that had "Dick Smith Electronics" printed on it. Wonder how old it was...

author: PedroDaGr8
author_rank: Super Contributor
timestamp: July 03, 2013, 05:35:18 pm
content: Also looks like the Tenma 72-320

author: Stonent
author_rank: Super Contributor
timestamp: July 03, 2013, 05:42:29 pm
content: Quote from: PedroDaGr8 on July 03, 2013, 05:35:18 pmI believe you're right.