Got to be woth £20 uk - Page 1
Forum section: electronics / beginners

author: Unknown
author_rank: Unknown
timestamp: June 10, 2013, 07:29:43 pm
content: http://www.ebay.co.uk/itm/171016345011?_trksid=p5197.c0.m619

author: Anks
author_rank: Frequent Contributor
timestamp: June 10, 2013, 07:50:34 pm
content: "High Precision" and china don't normally go together but you never know.

author: Unknown
author_rank: Unknown
timestamp: June 10, 2013, 07:55:11 pm
content: Quote from: Anks on June 10, 2013, 07:50:34 pmI know but for £20:00p curiosity is getting the better of me, it would be nice if it was a gem though. Dave should get one and tear it down

author: mikeselectricstuff
author_rank: Super Contributor
timestamp: June 10, 2013, 08:14:44 pm
content: For the amount of times you'd use something like this, the rechargeable battery is probably a bit OTT.And the 5V power in is NOT a USB connector - WTF?And how much accuracy do they lose with that switching system I wonder?

author: madires
author_rank: Super Contributor
timestamp: June 10, 2013, 08:16:13 pm
content: The question is if it's a genuine AD584LH. Just saw Chinese offers for US$4 and a more reliable one asks for US$35.

author: Galaxyrise
author_rank: Frequent Contributor
timestamp: June 10, 2013, 08:36:53 pm
content: The PentaRef from voltagestandard.com is only a little more, and probably worth it given the calibration, TLC, and good reputation (not to mention 5 user-selectable voltages.)

author: npelov
author_rank: Frequent Contributor
timestamp: June 10, 2013, 09:07:00 pm
content: @Galaxyrise I would also suggest that.It also can help you trim any adjustable reference like TL431 to <0.1% by measuring difference between the two with simple inexpensive voltmeter in mV range.

author: amyk
author_rank: Super Contributor
timestamp: June 11, 2013, 10:12:15 am
content: Quote from: madires on June 10, 2013, 08:16:13 pmDoes one even exist? I see no mention of an LH variant in the AD584 datasheet on Analog's site. The variants there range from $3.17 to $33.90 in 1ku so those prices don't look that far off.

author: Smithy
author_rank: Contributor
timestamp: June 11, 2013, 10:54:36 am
content: What about one these instead...http://shop.voltagestandard.com/product.sc;jsessionid=A1327A2186B7A7DAF0AB2221726E5D50.m1plqscsfapp01?productId=3&categoryId=1

author: madires
author_rank: Super Contributor
timestamp: June 11, 2013, 12:27:03 pm
content: Quote from: amyk on June 11, 2013, 10:12:15 amIt's not in the Rev C datasheet but in the older Rev A. The differences are:OUTPUT VOLTAGE TOLERANCEMaximum Error1 for NominalOutputs of:10.000 V +/- 5mV7.500 V +/- 4mV5.000 V +/- 3mV2.500 V +/- 2.5mVOUTPUT VOLTAGE CHANGEMaximum Deviation from +25°CValue, TMIN to TMAX210.000 V, 7.500 V, 5.000 V Outputs 5 ppm/°C2.500 V Output 10 ppm/°CBut I guess that the AD584LH isn't produced anymore.

author: iloveelectronics
author_rank: Frequent Contributor
timestamp: June 14, 2013, 04:09:19 pm
content: Martin just had a quick look at this device:Jump to around 22:04 to see his first look review.

author: madires
author_rank: Super Contributor
timestamp: June 14, 2013, 06:55:02 pm
content: Quote from: iloveelectronics on June 14, 2013, 04:09:19 pmLooks to be genuine. It amazes me that the producer can source the AD584LH for such a low price that he is able to sell the finished product for 20 bucks.

author: Fraser
author_rank: Super Contributor
timestamp: June 14, 2013, 07:40:13 pm
content: GBP20 is the average cost of an evening in the pub so I just stayed in this evening and ordered one

author: Bored@Work
author_rank: Super Contributor
timestamp: June 14, 2013, 08:14:11 pm
content: Quote from: Aurora on June 14, 2013, 07:40:13 pmAre you shure you ordered one with the "calibration certificate"? The ones I found on eBay and Aliexpress all didn't mention it, and only listed the PCB or PCB plus enclosure as the shipping contents.

author: Fraser
author_rank: Super Contributor
timestamp: June 14, 2013, 08:27:04 pm
content: No mention of certificate but I can check it against a recently calibrated lab meter so can produce my own calibration table

author: KJDS
author_rank: Super Contributor
timestamp: June 14, 2013, 08:52:30 pm
content: Quote from: Aurora on June 14, 2013, 07:40:13 pmI've regularly had rounds that cost three times more than that. I probably need slightly less drunkardly friends.

author: 807
author_rank: Frequent Contributor
timestamp: June 15, 2013, 10:10:06 am
content: Even cheaper if you buy in US$.Got mine for $24.69 = £16.23 at current PayPal rates.http://www.ebay.co.uk/itm/400452242651?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1423.l2649No mention of a certificate on any of the Ebay listings though.

author: staxquad
author_rank: Frequent Contributor
timestamp: June 15, 2013, 03:08:00 pm
content: Quote from: 807 on June 15, 2013, 10:10:06 ameven cheaper without the box @ US $15.99 (sold last month, don't know if more will be offered)http://www.ebay.com/itm/New-AD584LH-4-Channel-2-5v-7-5v-5v-10v-High-Precision-Voltage-Reference-Module-/221210908532?pt=LH_DefaultDomain_0&hash=item3381329774They are a bargain with the calibration certificate, giving 6 usable digits, but without the calibration certificate , you could only use 4 digits. If you're looking for a unit to verify calibration, without the calibration certificate, you're a little short in accuracy to even check a 20,000 count Fluke 87. With calibration certificate, or if you have access to a calibrated device to give it 6 digits of accuracy, it's good for a 300,000 to 500,000 count meter. MJLorton's test was impressive with calibration certificate.I considered what was on offer from a PentaRef ($61) to decade references and decided to watch out for decade references on Ebay as a better value for more versatility. Came across a 7 digit Kelvin Varley Divider (DAS57AL, $99.99), 0 to 1 volt DC and 0 to 10 volt DC, shown at auction dialed to 7.777700VDC and tested by an HP 34401A to 7.7776VDC, so I went for it.Testing after receipt revealed that set to 10.00000VDC, both my HP 3478A units showed 10.0000VDC with no flickering, steady the whole day (still at 10.0000VDC 2 days later, never turned off, did drop down to 9.99999VDC or 9.99998VDC when the temperature plummeted 1 or 2 degrees). My Fluke 87III showed 9.995VDC. Even my old Philips nixie showed 9.95VDC. Will be trying to verify the DAS57AL to it's full 7 digits, but presently, I think I have confidence in it's ability to verify the HP 3478A's 300,000 count.

author: iloveelectronics
author_rank: Frequent Contributor
timestamp: June 19, 2013, 02:52:40 am
content: I just got myself one of these. Measurements taken with my used HP3457A with unknown calibration history (numbers in brackets are the valued marked on the sheet that comes with the voltage ref):2.49841 (2.49840)5.0007 (5.00090)7.4977 (7.49807)9.9996 (10.00007)No complains here for the little money I paid

author: Stonent
author_rank: Super Contributor
timestamp: June 19, 2013, 04:16:08 am
content: Appears to be powered by a Samsung GT-i9000 battery

author: poorchava
author_rank: Super Contributor
timestamp: June 19, 2013, 05:51:44 am
content: What are they using to switch the voltage with the button? Analog mux? mosfets? Seems like most of those methods are no good for high precision measurements...

author: Stonent
author_rank: Super Contributor
timestamp: June 19, 2013, 08:17:02 am
content: I see 4 P-FETs and a JFET OpAmp, that's what I could get from part searches, also a charging chip in the top corner.The ebay description also saysQuoteSo some kind of Microcontroller? That T1 chip looks suspicious. Pin 8 appears to be grounded, it could be a PIC12 series?

author: madires
author_rank: Super Contributor
timestamp: June 19, 2013, 12:55:29 pm
content: Quote from: Stonent on June 19, 2013, 08:17:02 amThere are two ways do set the output voltage of the AD584. One is to connect the output pins as described in the datasheet. And the other one is to connect a voltage follower to one of the outputs or each output (you can have all 4 output voltages at the same time).Based on the 4 p-ch FETs and the single OpAmp I'd guess they switch the selected output of the AD584 to the OpAmp acting as a buffer.

author: Fraser
author_rank: Super Contributor
timestamp: June 27, 2013, 12:16:51 pm
content: My voltage reference unit arrived today from this seller:http://www.ebay.co.uk/itm/400452242651?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1497.l2649GBP16.10Ordered from Hong Kong on 22 June, arrived with me in the UK 27 June.... pretty good serviceMy comment on it....SUPERB !It arrived wrapped in a soft 'silk' cloth to prevent scratches. It was then wrapped in 2 layers of bubble wrap before being paced in a padded envelope.It includes the all important calibration certificate. I checked the output on my Fluke 87 III using its 4.5 digit mode. All readings tallied with the calibration certificate within the capabilities of 4.5 digits. I will test the unit on a calibrated lab multi-meter tomorrow.For the money I consider this a bargain purchase. I definitely recommend buying the cased unit as the case protects the PCB and is very well made.I can check its calibration any time I want with the office calibrated unit so I will effectively have a calibrated transfer standard.Whoopee !I purchased some close tolerance resistors last year so now I just need a current standard....time to look at the specs for this unit to see if it can drive a resistor load and what current it can produceOtherwise I will use it as a voltage reference to build a simple current reference add-on. GBP16 well spent.Picture attachedI have another in transit from China (this one came from HK) I will be ordering another from the HK supplier and it will be interesting to see how the three units age over the coming year. At GBP16 these really are worth having lying around the lab for a quick meter accuracy check.

author: 807
author_rank: Frequent Contributor
timestamp: June 27, 2013, 12:43:17 pm
content: Quote from: Aurora on June 27, 2013, 12:16:51 pmWOW. Just 5 days from Hong Kong!I placed my order with the same seller on 15th June. Still waiting!

author: Fraser
author_rank: Super Contributor
timestamp: June 27, 2013, 12:49:29 pm
content: I was surprised as well. Just lucky I guess. I have ordered another so will see how long that takes.It is good to find that the calibration certificate comes with it as standard though.I believe you will be very pleased with your purchase. I bought a kit of parts to build my own 5V voltage reference. I see no need to do so now. this unit cost less, does more and comes cased and calibrated.The only daft thing is that its comes without a charging cable of any sort. A USB charge socket on the unit would have made sense as it is 5V.

author: 807
author_rank: Frequent Contributor
timestamp: June 27, 2013, 01:01:33 pm
content: Shhh...don't give them ideas about paying extra for a certificate. LOL.Yep. I'm like a little boy on Xmas morning! Can't wait to get my hands on the package.Now I just need to buy a new 50000 count DMM to compliment it.

author: Fraser
author_rank: Super Contributor
timestamp: June 27, 2013, 01:20:59 pm
content: Good point. I have removed my comment in case they decide to change their price !CheersFraser

author: G7PSK
author_rank: Super Contributor
timestamp: June 27, 2013, 05:35:53 pm
content: I have also just ordered one, so will be interesting to see how fast that arrives. Also be good to see how my meters compare as well.

author: Fraser
author_rank: Super Contributor
timestamp: June 28, 2013, 08:54:18 am
content: My second unit from this supplier is already in the post to me....nice fast despatchI have already identified several multimeters that I own that are less accurate than my Fluke's. OK they are not miles off spec but they could do with either calibration or marking as not 'Fluke' precise instruments. Thankfully I have my Fluke and Advantest bench meters if I need really accurate readings. It was interesting to see the variation in readings across some of my collection of multimeters though. My AVO Megger units were as accurate as my Fluke 87 III. My Wavetek DM23XT, less so.My Voltage reference is stated as providing the following voltages at 21 degrees C :2.50093V5.00165V7.50336V10.00360VMy old Uni-T UT39A gave the following readings:2.48V4.96V7.45V9.93VAnother old meter...the Wavetek DM23XT manual ranging:2.50V5.01V7.52V10.02VOld Wavetek DM73A Probe meter:2.504V4.99V7.49V9.99VMy Fluke 87 III readings:3.5 Digit mode:2.500V5.00V7.50V10.00V4.5 Digit mode:2.501V5.002V7.503V10.004VA simple example of the difference between a relatively old Fluke 87 III and a UNI-T meter.... One remains accurate, the other not so accurate....but was it ever 'Fluke' accurate

author: ttp
author_rank: Regular Contributor
timestamp: June 28, 2013, 12:13:31 pm
content: Quote from: poorchava on June 19, 2013, 05:51:44 amLook at datasheet, you apply low or high to few pins and output voltage changes, all precision magic is done inside the chip.

author: 807
author_rank: Frequent Contributor
timestamp: July 04, 2013, 11:47:42 am
content: I'm beginning to get a bit concerned now.It's been 18 days (14 working days) since dispatch. According to the listing 92% of items are received within 14 working days, although I don't know how this is measured, as the items are not tracked or signed for.I have to wait the full 30 working days before contacting them about a lost item

author: peter.mitchell
author_rank: Super Contributor
timestamp: July 04, 2013, 11:58:26 am
content: Don't fret, I usually order heaps of cheap crap from china and hong kong on ebay and aliexpress and dealextreme, my latest order was 17 different things from 17 different suppliers, 10 have arrived, 7 have not, it has been 23 days. I still expect it all to arrive, it has just started to come in in the past week.

author: Unknown
author_rank: Unknown
timestamp: July 07, 2013, 08:12:32 pm
content: Quote from: 807 on July 04, 2013, 11:47:42 amIt takes a good time I ordered an opto checker , for checking chips , it took a month and a half to arrive, so relax, it will get to you eventually, I've ordered loads of stuff from Hong Kong, you got to sort of forget it.

author: 807
author_rank: Frequent Contributor
timestamp: July 10, 2013, 11:03:17 am
content: Phew! It arrived on Monday.Will be having a play with it later today with my collection of old DMM's, but haven't really got a meter to fully test it with at the moment.Still compiling a short list of 40000/50000 count DMM's.

author: Unknown
author_rank: Unknown
timestamp: July 10, 2013, 11:12:43 am
content: I was the first to mention these things and haven't got around to order one myself yet, a must do soon, let us know how you get on with it.

author: Fraser
author_rank: Super Contributor
timestamp: July 15, 2013, 11:58:40 am
content: I have two of these in transit to me at the moment.A word of warning, after chasing the seller regarding one overdue unit, he advised that he was having problems with the HK Post. They were spotting the lithium battery and kept returning the units to him as prohibited items. The other units seller confirmed he was also having the same problem with China Post. They have resent all the returned items but the detection/rejection rate appears high.Get them while you still can. I suspect they will start to be shipped without the battery.

author: 807
author_rank: Frequent Contributor
timestamp: July 15, 2013, 12:22:39 pm
content: That sounds a bit odd. Were the HK & China post opening their packages to check?Perhaps they should try & hide the battery by wrapping it before sticking it to the bottom of the case!

author: Fraser
author_rank: Super Contributor
timestamp: July 15, 2013, 12:39:29 pm
content: X-Ray safety scans ?

author: 807
author_rank: Frequent Contributor
timestamp: July 15, 2013, 01:12:25 pm
content: Quote from: Aurora on July 15, 2013, 12:39:29 pmHmm..possibly.Perhaps the sellers should wrap the whole unit in bacofoil.

author: iloveelectronics
author_rank: Frequent Contributor
timestamp: July 15, 2013, 01:19:35 pm
content: Quote from: 807 on July 15, 2013, 12:22:39 pmIf they are a mass mailer they would have an account with HK Post and China Post for their postings. And once some of their packages are spotted I suppose it's easy for the post office/customs to spot check more of their packages on a regular basis.

author: Fraser
author_rank: Super Contributor
timestamp: July 15, 2013, 01:40:18 pm
content: Bacofoil = Aluminium = transparent to X-Ray due to very low density

author: Unknown
author_rank: Unknown
timestamp: July 15, 2013, 08:04:12 pm
content: Just ordered one. , guess that will be around a month

author: Fraser
author_rank: Super Contributor
timestamp: July 15, 2013, 11:52:09 pm
content: I don't think you will be disappointed

author: 807
author_rank: Frequent Contributor
timestamp: July 16, 2013, 08:12:14 am
content: Quote from: Aurora on July 15, 2013, 01:40:18 pmOops!Now where's that embarrassed emoticon? Ahh...here it is...LOL.

author: amyk
author_rank: Super Contributor
timestamp: July 16, 2013, 08:37:42 am
content: AFAIK they are still allowed by sea and land, so you can still get them, it'll just take a lot longer...

author: madires
author_rank: Super Contributor
timestamp: July 16, 2013, 11:08:47 am
content: Quote from: amyk on July 16, 2013, 08:37:42 am... unless the ship breaks apart in the Indian Ocean and 7000 containers are donated to the recreation of coral reefs :-)http://www.bloomberg.com/news/2013-06-19/mitsui-o-s-k-starts-probe-of-ship-split-in-two-in-indian-ocean.html

author: G7PSK
author_rank: Super Contributor
timestamp: July 16, 2013, 03:31:43 pm
content: I ordered one on June 28th and have still not recieved it yet, I expect it will get here eventually but with the present aircraft scare I suspect they will be looking a bit more closely for batteries in the air mail. I would rather have t source my own battery than have it floating around on a barge somewhere of the Somalia cost.

author: M. András
author_rank: Super Contributor
timestamp: July 16, 2013, 04:48:34 pm
content: i ordered 1 in last month 15th and it showed up yesterday, apart fro mbeing 28celius in my room it was good with my fluke it has only its original factory calibartion so i trust that over a little acrylic box what travelled trought half the globe i wonder if it powers the reference all the time or when the mcu switches it on

author: bilko
author_rank: Frequent Contributor
timestamp: July 16, 2013, 05:06:19 pm
content: I ordered mine 27th June, still waiting

author: pmcouto
author_rank: Unknown
timestamp: July 16, 2013, 05:42:06 pm
content: Hi,I have received mine yesterday, ordered June 15th.As already mentioned by other posters, my Voltage Reference also includes a small piece of paper (sorry, a Calibration Certificate) with measured values at the factory.Compared to the values measured with my brand new Agilent 34461A, it is almost spot-on!Voltage – Factory “paper” – Agilent 34461A2.5 V – 2.50033 V – 2.50028 V5 V – 5.00240 V – 5.00241 V7.5 V – 7.50129 V – 7.50136 V10 V – 10.00285 V – 10.00296 VIn my opinion, it is well worth 20 GBP!Regards,Pedro Couto

author: Fraser
author_rank: Super Contributor
timestamp: July 26, 2013, 02:05:40 pm
content: My additional two units that are travelling to the UK are very much overdue nowI have contacted the seller again after the deadline he stated for delivery expired. One has been on order since the day this thread started. At least I have one to use in the workshop.

author: G7PSK
author_rank: Super Contributor
timestamp: July 26, 2013, 03:37:49 pm
content: My unit is also overdue it is now a full month since the order. I suppose it could be held up in customs, that happened to me once, They contacted me to say that if I did not pay the duty within seven days they would send the item back to the sender as this was nearly six months after it had arrived at the customs and they had just been sitting on it expecting me to know that they had when the sender could not trace it I sent them a rude message telling them exactly where to place the item.

author: staxquad
author_rank: Frequent Contributor
timestamp: July 26, 2013, 04:08:05 pm
content: edit: Price: US $21.88, going down!I ordered mine on 06/28/13 and got it last week (used the link to the ebay item provided by Aurora)44% chance of arrival after 14 calender days for Canada79% chance of arrival after 20 calender days for Canada72% chance of arrival after 14 calender days for UK92% chance of arrival after 20 calender days for UKworth it with the calibration sheetalready did a mod to it to extend it's usefulnesswith the calibration sheet in it, it won't be lost

author: 807
author_rank: Frequent Contributor
timestamp: July 26, 2013, 05:50:49 pm
content: Quote from: staxquad on July 26, 2013, 04:08:05 pmYep. Good idea.First thing I did when I received mine was to write the cal data down on a few sheets of paper & spread them around, so, hopefully, I could always find one if I lost the original. LOL.Obviously, yours will never get lost!

author: Fraser
author_rank: Super Contributor
timestamp: July 26, 2013, 08:24:56 pm
content: The supplier of one of my units is sender another and considered the first one lost. I am wondering if the units are getting intercepted somewhere along the line as they are not declared to contain a battery, and a Lithium one at that. I have accepted his offer so we shall see if it is second time lucky. My missing units are from two different sellers.

author: M. András
author_rank: Super Contributor
timestamp: July 26, 2013, 09:47:45 pm
content: that can be a problem too, anyway 2 of my packages is lost or hangs somewhere in the line from china both of them was due to shipped till 2 weeks ago, but this reference arrived so i dont know what the hell is with the chinese post sometimes (10 50x25x10mm heatsinks are missing and 60 ic clips/minigrabbers both of the sellers asked to wait and its already passed 30 days)

author: G7PSK
author_rank: Super Contributor
timestamp: July 28, 2013, 08:37:13 am
content: I have also contacted the seller and he is sending out another unit. Last time that happened 2 sets of test leads arrived on the same day, for some strange reason the second set dislodged the first set which was stuck in the postal system somewhere, the first was sent regular mail and the second was sent swiss post, so it was not the senders fault but the post system.

author: Fraser
author_rank: Super Contributor
timestamp: August 10, 2013, 12:25:55 pm
content: Most of the replacements for those that went missing in transit have just arrived. A London based post forwarding agent was used. All of the units that I have purchased have been supplied with a calibration certificate and were wrapped in soft cloth and bubble wrap to protect them. One unit is outstanding but I expect its delivery this week from the forwarding agent.For info. The Hong Kong based supplier was an honourable seller and sent replacement units without any problems. Top marks. The China based seller also sent a replacement unit without any issues and is also a most honourable person.The two sellers that I purchased the units from are shown below:haruyr_kb - based in Hong Kong.1984yht888 - based in ChinaMy experience with these two sellers has been simply superb. Yes the items became lost in transit, but they behaved impeccably with superb communications and customer service.I am still wondering whether these units are getting spotted in airline checks and confiscated for containing a lithium battery and not having a warning of such shown on the packaging, in line with IATA regulations. For separate consignments of these units from HK and China to go missing almost simultaneously is most unusual.

author: G7PSK
author_rank: Super Contributor
timestamp: August 10, 2013, 03:32:24 pm
content: I ordered mine from the Hong Kong seller, he has sent another bus as of yet that has not arrived, I wonder if the problem is royal mail as from the 15th July they introduced new regulations regarding what they would carry and I just had trouble getting the post office to accept a mobile phone I was returning as it had failed, the person behind the window was arguing despite the leaflet saying that it was OK for inland mail as long as the battery was either in the equipment or well wrapped so as not to crush in transit.

author: Fraser
author_rank: Super Contributor
timestamp: August 10, 2013, 08:59:11 pm
content: Oh no, not more regulations !I had enormous trouble shipping an HF radio receiver to Italy as the P.O. Clerk insisted such could not be imported to Italy due to local regulations. My receiver became an "Lowe HF-225 HF Demodulator" on the paperwork and suddenly it was OK to ship. There is always a way to ship something, but care is needed in the description of the contents

author: G7PSK
author_rank: Super Contributor
timestamp: August 10, 2013, 09:30:54 pm
content: Regulations are all well and fine until you get to the "jobsworth" thats when the trouble begins.

author: ecat
author_rank: Frequent Contributor
timestamp: August 13, 2013, 06:53:56 am
content: Quote from: G7PSK on August 10, 2013, 03:32:24 pmThe one I purchased from haruyr_kb on the 1st of July arrived July 25th, if that information is of any help to you in your sleuthing.

author: Codemonkey
author_rank: Regular Contributor
timestamp: August 13, 2013, 07:12:58 am
content: Quote from: ecat on August 13, 2013, 06:53:56 amI ordered one on 28th June and it didn't arrive until somewhere between 25th July - 6th August (Delivered to the office but I was away). Got round to testing it yesterday and it didn't work (no output from it, but the LED's lit and you could select the voltage with the button). Eventually traced the fault to being one side of the inductor that wasn't soldered down (it had lifted up on one side during soldering, if you pressed on it gently it all worked so guess they got lucky when it was tested).

author: M. András
author_rank: Super Contributor
timestamp: August 14, 2013, 05:45:20 pm
content: anyone who got his unit and have a scope could you hook it up to its output? i measure 150mv pp with my fluke on dcv and when measuring ac,dc it shows 150mv ac

author: Nermash
author_rank: Frequent Contributor
timestamp: August 14, 2013, 07:49:32 pm
content: I just measured mine with Fluke 287 and it is 400uV noise on AC mV range. Are you charging it?

author: M. András
author_rank: Super Contributor
timestamp: August 14, 2013, 08:27:08 pm
content: Quote from: Nermash on August 14, 2013, 07:49:32 pmno its fully battery powered it was fully charged when arrivededit: i changed to ac mV range too its around 3-400uv. but on dcv on the 10 range the peak values are 10.13/9.88 on the 2.5v range its ten times smaller deviation. as i dont have a scope i cant see why it measures this

author: ecat
author_rank: Frequent Contributor
timestamp: August 14, 2013, 09:07:41 pm
content: Quick scope test with the unit on battery power set to 10V:AC coupled x1 scope probe connected to the flying leads I have plugged into the unit... A very funky wave form peaking at about 500mV.AC coupled x1 scope probe connected directly to the sockets on the unit... Wave is still funky but down to 150mV max peak.Replacing the ground connector on the probe with a short coil of stiff wire and connecting directly to the sockets on the unit... Funky wave now around 60mV peak. But, I get the much the same 60mV peak wave form without the unit connected, so some sort of common noise? I do see an additional 20mV peak wave with the unit connected but I'd need to eliminate the background noise sources before reaching a conclusion.short coil of stiff wire: EEVBlog #441Edit:I've had my unit connected to a 6 1/2 digit Solartron 7150+ since the day it arrived. The least significant digit on the 7150 is not very stable at the best of times (+/-3 iirc spec from new), that said I don't recall seeing the 10V reading going below 9.99995 or above 10.00008, and that is with the big temperature swings we've had in Scotland over the past few weeks.

author: Unknown
author_rank: Unknown
timestamp: August 14, 2013, 10:03:42 pm
content: A quick and dirty test:Measured mV AC with a 4.5 digit handheld Fluke: 0.3 mVDCV at 10V setting: stable 9.998 V readingWith a 100 MHz 10x scope probe on a 500 MHz scope (no BW limit) on 10 mV/div (too lazy to dig out a 1x probe) with AC coupling: 1.2mV rms with the tip and ground lead connected to the same point, 1.7 mV rms with the tip and ground connected across the reference (set to 2.5 V)I measured it with a few 6.5 digit meters a few weeks ago, and I think it was stable except the last digit that would very slowly drift up and down.So no indication of excessive noise in my sample. The results suggest common noise picked up by the meter / scope, although I didn't take any precautions to minimize loop area either (standard ~8cm ground lead).

author: M. András
author_rank: Super Contributor
timestamp: August 15, 2013, 01:55:54 pm
content: i measured those with a fluke 289 in peak detect mode. and ac+dc the low noise was in plain acv mode, but the plain dc reading is stable

author: Fraser
author_rank: Super Contributor
timestamp: September 02, 2013, 03:45:44 pm
content: Just to confirm, all of my units have now arrived. Some took an awful long time but at least they made it in the end. The missing units never turned up so they were likely lost or intercepted in transit due to the lithium battery.The units have already proved their worth when sorting through a pile of stored multi-meters. I could quickly sort out the good from the bad, the keepers from the bin jobsNo surprise that my old Altai meters from the 1980's were bin jobs ! The AVO analogue meter was still reading accurate though

author: M0BSW
author_rank: Frequent Contributor
timestamp: September 12, 2013, 07:26:45 pm
content: Ok now the dust has settled, I bought one of these , for the price it can sit in the shack, it will be interesting to see ,what my meters read, I know I'm a bit slow in reacting to these, I never rush in to anything.

author: KJDS
author_rank: Super Contributor
timestamp: September 12, 2013, 08:30:19 pm
content: I ordered a few last week, hopefully they won't take too long to turn up.

author: G7PSK
author_rank: Super Contributor
timestamp: September 12, 2013, 09:19:31 pm
content: Mine turned up at last, took long enough first one never showed up and second one was over a month in arriving.I have no real way of testing its accuracy as I only have a UniT 61E an Amprobe and an AVO but my brother in law works at the National Physical Laboratory so I will see if he can test it for me some time.

author: staxquad
author_rank: Frequent Contributor
timestamp: September 19, 2013, 09:33:02 pm
content: mine diedTried to turn it on, nothing.Plug in 5v, and all 4 leds rapidly flashing dimly with no Volt Ref output, unplug.Voltage low on the battery so I disconnect and connected another 3.7v Li-PoAll 4 leds still flashing dimly with no output.Accidentally short the battery leads and the unit stops flashing dimly.Turn it on and it works.Checked the values and same as before, as the spec sheet.Charged the battery externally before reattaching the leads.Had to short the leads again to reset from all leads flashing dimly.Volt Ref works again with same reattached battery.Battery doesn't charge on the Volt Ref, will have to do it externally.I always made sure I am sure to turn the Volt Ref off before putting it away, but maybe I missed the last time and it caused the failure.Same day my Sony NEX 5N digital camera goes on the fritz.Turn it on, no image, just the outlying info, stuck on 30" and ISO 1600, shutter or movie button will not activate.Screen goes out completely most of the time.Have to turn off the camera, pull out the battery, put back in the battery, turn on the camera, plug in the USB just to get to the Menu screen, change things, but it reverts, it's a dead end.Got the camera with 1.0 firmware and updated to 1.1 last year. Can't reload the same firmware, but luckily Sony had 1.2 on their website, so the plan was to try to update the firmware to try to unlock the freeze. Finally get USB to be in Mass Storage mode by uploading a few photos from the camera, it stayed in USB Mass Storage mode (wouldn't stay when I changed it in the menu and it won't allow a connection without), so clicked the firmware update program, clicked safely remove hardware for the camera in Windows so it could connect, and uploaded the new 1.2 firmware and the camera now works.so what caused the 2 devices to lock out at the same time?Aliens?NSA, RCMP probing the house with electronic waves? (who knows what they are looking for)Smart Meter just 10 feet away on the other side of the wall where the camera and the volt ref were parked?coincidence?'

author: KJDS
author_rank: Super Contributor
timestamp: September 20, 2013, 07:12:37 am
content: Mine arrived a couple of days ago. Need to find the right connector to charge them.

author: M0BSW
author_rank: Frequent Contributor
timestamp: September 20, 2013, 10:33:19 am
content: Got mine today, straight down to my friends at the calibration centre it checks out 100% OK with the supplied chart, so ,like a kid with a new toy, I tried it on my multimeter, remember nothing fancy here uni T61E out by 2 to 3 counts everywhere, Digitek again 2 to 3 everywhere , Ideal Alphatek 1 sometimes flickering to 2 counts out lower end only, but the absolute STAR is 30 Years plus old Farnell TMS, English made locally, BANG ON EVERYWHERE go ENGLAND

author: KJDS
author_rank: Super Contributor
timestamp: September 20, 2013, 11:01:44 am
content: I've got four. Just put the first one on charge. Once they've all had a while to charge up I'll compare them to a few Keithley 2015THD meters and post up the results, as well as an AVO 8 and some Fluke 25s and Wavetek 2015, 2020 and 2030. Will be interesting to see what they all read.

author: M0BSW
author_rank: Frequent Contributor
timestamp: September 20, 2013, 11:47:11 am
content: Quote from: KJDS on September 20, 2013, 11:01:44 amI'm really looking forward to the AVO results, as I'm looking at one of these on ebay

author: KJDS
author_rank: Super Contributor
timestamp: September 20, 2013, 02:28:09 pm
content: ok, so here is what I found. I numbered the references 1 through 4.With ref 4,Wavetek 2020 wavetek 2015 wavetek 2020 Wavetek 2015 Fluke 25 Fluke 25 AVO 8 IsoTech 205 Isotech 2052.500 2.496 2.500 2.500 2.499 2.499 2.498 2.506 2.4985.004 5.00 5.002 5.00 5.00 5.00 4.95 5.01 4.997.504 7.49 7.500 7.50 7.49 7.50 7.45 7.52 7.4910.007 9.99 10.002 10.00 9.99 10.00 9.98 10.03 9.99and on three Keithley 2015THDs HP3478A values on the certificate2.49942 2.49940 2.49939 2.49940 2.499465.00208 5.00204 5.00202 5.0020 5.002117.50057 7.50050 7.50049 7.5004 7.50059110.00266 10.00257 10.00255 10.0025 10.00266Reference 2 was faulty, providing ever changing readings.Reference 1 on the three keithleys and the HP3478Aon three Keithley 2015THDs HP3478A values on the certificate2.49965 2.49964 2.49963 2.49965 2.499715.00213 5.00210 5.00208 5.0021 5.002187.50225 7.50220 7.50218 7.5022 7.5023010.00427 10.00420 10.00417 10.0042 10.00430Ref 3 on three Keithley 2015THDs HP3478A values on the certificate2.49861 2.49861 2.49860 2.49861 2.498685.00140 5.00130 5.00136 5.0013 5.001377.49879 7.49873 7.49871 7.4987 7.4986610.00113 10.00105 10.00102 10.0010 10.00089I'm a little disappointed that number two is unstable on all ranges, but nowhere near as if I'd only bought one or two.I'm happy that all the meters are giving reasonable readings. I only let the bench meters warm up for half an hour or so. The handheld meters were all tested straight after turning on, so typical of normal hobby use.The three references that do work give results consistent with their certificates. I'll keep measuring a few over time to see how they drift.

author: Fraser
author_rank: Super Contributor
timestamp: September 20, 2013, 04:19:48 pm
content: From what we have seen on this thread, the certificate that comes with the units is quite accurate. With that in mind your Reference number 2 was likely working when made. You may be lucky and find a dry joint on the PCB that has been disturbed by the journey to you.I have four of these now and all are holding their 'calibration' so far.

author: staxquad
author_rank: Frequent Contributor
timestamp: September 20, 2013, 09:44:48 pm
content: Quote from: Aurora on September 20, 2013, 04:19:48 pmPrinted on the certificate is the device used for the measurements, an HP 34401A (6 1/2 digit). So if the 34401A is within calibration, the numbers should stack up with other devices of similar precision within calibration validating the values, for the stability period of the Volt Ref.

author: Noldir
author_rank: Newbie
timestamp: October 04, 2013, 12:23:59 pm
content: Got mine as well, the small sheets says:2.500 = 2.699325.000 = 5.001187.500 = 7.6995210.000 = 10.00096Aren't the 2.5 and 7.5 values a bit...off? 0.2 is quite a bit of deviation..

author: mianchen
author_rank: Regular Contributor
timestamp: October 04, 2013, 12:41:18 pm
content: Quote from: Noldir on October 04, 2013, 12:23:59 pmare u sure the 6s are 6s not 4s?Sent from Mars

author: Fraser
author_rank: Super Contributor
timestamp: October 04, 2013, 03:08:55 pm
content: I concur.My certificate has some hard to read numbers, 4's being very close to 6 shaped !The 2.5V sets the calibration for the whole unit so that should be accurate if the derivatives are.Fraser

author: Noldir
author_rank: Newbie
timestamp: October 04, 2013, 05:16:55 pm
content: Quite positive they are sixes.... (as in 99% positive unless someone has a awfully weird 4)

author: Noldir
author_rank: Newbie
timestamp: October 04, 2013, 05:19:47 pm
content: Here's a piccie

author: pmcouto
author_rank: Unknown
timestamp: October 04, 2013, 05:29:13 pm
content: Don't be so sure - That must be a Chinese 4

author: Kostas
author_rank: Regular Contributor
timestamp: October 04, 2013, 05:35:59 pm
content: Quote from: Noldir on October 04, 2013, 05:19:47 pmLook at the header, the measurements were done at 26°C. If you look carefully, you'll see that this six is quite different than the other "sixes". They have the ending line going downwards. I'd say they are fours.

author: KJDS
author_rank: Super Contributor
timestamp: October 04, 2013, 06:01:21 pm
content: Quote from: Kostas on October 04, 2013, 05:35:59 pmI just looked at three of mine and have to agree. Two of them have the 4s very clearly as 4s. The third has the 4s more like those in the image

author: PA0PBZ
author_rank: Super Contributor
timestamp: October 04, 2013, 07:19:37 pm
content: Looks like my label was written by the same guy:

author: Fraser
author_rank: Super Contributor
timestamp: October 04, 2013, 08:03:58 pm
content: They are the number 4. As I stated, the 2.5V ref sets the others so it can't be a number 6 if they are close to right. I agree that they look like a 6 but this chap is writing in a numerical language not native to him, so could be forgiven for poor style, and I suspect he is doing the tests 'at speed' to keep up with demand.My 4 units number 4's are a range of good, to the same as yours, purely due to poor style.

author: Noldir
author_rank: Newbie
timestamp: October 04, 2013, 10:12:26 pm
content: Quote from: Aurora on October 04, 2013, 08:03:58 pmAh yes, I'd almost forgot that he's not quite used to writing in western numeralsAnd of course I'm quite forgiving of his style, he just put me on the wrong footing by his otherwise good handwriting

author: Noldir
author_rank: Newbie
timestamp: October 04, 2013, 10:13:28 pm
content: Quote from: PA0PBZ on October 04, 2013, 07:19:37 pmYup, looks the same to me! And, looking at yours I can definitely see how that "6" could be a 4

author: staxquad
author_rank: Frequent Contributor
timestamp: October 04, 2013, 11:44:11 pm
content: Quote from: PA0PBZ on October 04, 2013, 07:19:37 pmFor 10.000V he has 10.00094, with the 4 looking more like a 4, but still showing that hook he uses to drop down to finish off the 4. He uses one stroke to make a four while most people use 2.

author: iloveelectronics
author_rank: Frequent Contributor
timestamp: October 05, 2013, 07:18:51 am
content: Being Chinese I can say with 100% certaint that it is a very typical “4” written by a Chinese person.I have travelled to many diiferent places and I have always found it very interesting the ways different people in different parts of the world write their numbers. The “1” written in Europe, for example, is very interesting. It looks like a upside down “V” to me

author: Mr Smiley
author_rank: Frequent Contributor
timestamp: October 25, 2013, 02:50:09 am
content: uncased £9.83http://www.ebay.co.uk/itm/290994447231?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1438.l2649cased £11.13http://www.ebay.co.uk/itm/AD584LH-4-Channel-2-5v-7-5v-5v-10v-High-Precision-Voltage-Reference-Module-505/290998772680?_trksid=p4069.m2059&_trkparms=aid%3D111000%26algo%3DREC.CURRENT%26ao%3D1%26asc%3D27%26meid%3D2222490802175318086%26pid%3D100039%26prg%3D1011%26rk%3D1%26rkt%3D4%26sd%3D290998772680%26

author: iloveelectronics
author_rank: Frequent Contributor
timestamp: October 25, 2013, 03:31:32 am
content: Their pricing is nuts.... I know because I have actually ordered a batch from the producer of these so I know the costs. Plus they are still trying to sneak the lithium batteries through HK Post, practically slowing the entire system down (due to screening and rejecting at least some of their packages) for everybody else

author: mianchen
author_rank: Regular Contributor
timestamp: October 26, 2013, 04:22:45 pm
content: Got mine today:Volt RefUT-61EFluke 87III(1)Fluke 87III(2)HP 3468A2.5002.498492.4962.4972.4982.498175.0005.002334.9995.0015.0015.00187.5007.498847.4967.4977.4977.498010.00010.002219.99910.0009.99910.0012My little uncalibrated DIY AD588JQ voltage ref gives "better" resultsUT-61EFluke 87III(1)Fluke 87III(2)HP 3468A5.0004.9984.9995.0005.000310.0009.99810.0009.99910.0007Which one should I trust? I don't need high precision measurement, but it's kind of nice to know which reference is more 'real'

author: Fraser
author_rank: Super Contributor
timestamp: October 26, 2013, 04:44:50 pm
content: To be clear, the Chines unit is NOT a voltage standard, it is a reference...... meaning it generates a stable voltage that may be accurately measured by a calibrated meter and the voltages recorded for comparison with an unknown meters readings.The Chinese unit is not calibrated. It generates the set voltages from the reference IC and should continue to produce those voltages for a reasonable period of time and over a reasonable temperature range.A voltage standard should produce far more accurate voltages than these units i.e.2.50000V5.00000V7.50000V10.00000V

author: Unknown
author_rank: Unknown
timestamp: October 26, 2013, 05:34:39 pm
content: Two properties are important: stability and calibration. You can look up the stability specs for the two references and compare. The Chinese one has the advantage that it was calibrated on a fairly accurate Agilent 34401A. As Aurora states, the actual value is of little importance, as long as it's known accurately, which it is in the case of the Chinese reference.Quote from: Aurora on October 26, 2013, 04:44:50 pmMeasuring the output and writing the values on a piece of paper is calibration. It's not NIST-traceable and you may or may not decide to trust it, but it is a calibration.Quote from: Aurora on October 26, 2013, 04:44:50 pmMore accurate voltages or nice round numbers? This difference is rarely important, since most meters can be calibrated with any arbitrary voltage within their range. To me this could qualify as a transfer standard, though not the most accurate one. Even calibration of 'real' transfer standards like the Fluke 732B often consists of very accurately measuring its output voltage. There's usually no compelling reason to adjust it to exactly read 10V or 1.018V.

author: tmammela
author_rank: Contributor
timestamp: October 26, 2013, 07:45:04 pm
content: One reason why these are so cheap must be that they are not burned in. I just ordered a DMMCheck Plus from voltagestandard.com and they have 250 hours of burn-in to stabilize the chip a bit. Here:http://www.voltagestandard.com/Tech_Data.htmlyou can see that during those first 250 hours stability is really poor. So if you get a cheap chinese one, it might be ok for the first few hours but then it will drift out of spec.

author: Mr Smiley
author_rank: Frequent Contributor
timestamp: October 26, 2013, 09:25:49 pm
content: Quote from: tmammela on October 26, 2013, 07:45:04 pmIf anyone who gets one of these checks their meters and records their measured values, And the modules drift over time till, as you say, burnt in, and then measures them again with the same meters, could the new measured values be used to determine the drift and new burnt in values for the module

author: mianchen
author_rank: Regular Contributor
timestamp: October 26, 2013, 10:45:54 pm
content: What is the definition of burn in? All these Chinese Refs are made with salvaged/used/old AD584 pulled from other devices, surely they have already been used for many a hour before their new lives in these Voltage Refs

author: Mr Smiley
author_rank: Frequent Contributor
timestamp: October 27, 2013, 12:50:23 am
content: Hi,Has anybody had one of these on long term test

author: ddrl46
author_rank: Regular Contributor
timestamp: October 31, 2013, 01:34:18 pm
content: Ordered one of these about 2 months ago and I still haven't received it, probably due to the recent lithium battery screening from Hongkong post.

author: staxquad
author_rank: Frequent Contributor
timestamp: December 05, 2013, 03:06:05 am
content: AU $1.00 upgrade to the Volt Refadding mini USB recharging capability (rather than plugging in 5v from a wall adapter)plugged in the USB mini cable from my laptop to charge, then moved the plug to my camera to upload the picturesDurable 1PCS 5V Mini USB 1A Lithium Battery Charging Board Charger Module B98Bhttp://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=231099090848

author: Mr Smiley
author_rank: Frequent Contributor
timestamp: December 05, 2013, 03:34:42 am
content: Don't these units already have a lithium charger built inI can see the advantage of using a standard off the shelf usb leadps, just got mine, took 5 weeks. I noticed that mine has a cal temp of 20'C ( I'm in the UK where things are calibrated at 20'C ) and others I’ve seen on line, like yours have a cal temp of 23'C.I wonder if their temp calibrated ( just measured, cal would mean adjusted ) for specific regions

author: KJDS
author_rank: Super Contributor
timestamp: December 05, 2013, 06:58:42 am
content: Quote from: Mr Smiley on December 05, 2013, 03:34:42 amI'd put money on it being what ever temperature their thermometer is showing at the time

author: mianchen
author_rank: Regular Contributor
timestamp: December 06, 2013, 10:33:41 pm
content: Or check the weather forecast of Shenzhen before you order if you want a specific cal temp.sent from Mars

author: SeanB
author_rank: Super Contributor
timestamp: December 07, 2013, 02:10:22 pm
content: Mine is in the post thanks to Frankie, and I have a nice little BLB-2 already waiting for it. Tried this battery which has been on a shelf for about 5 years and it still had 3.7V on it. Charged for an hour to 4.0V and it was still very happy and is sitting at 3.79V.

author: M0BSW
author_rank: Frequent Contributor
timestamp: December 07, 2013, 04:13:54 pm
content: I bought one of these and I have to say, mine is a very accurate device indeed and measures , exactly to the certificate with it. to my surprise both my Ideal Alphatek meters measure spot on, uni T 61E is out by 2 counts.

author: Macbeth
author_rank: Super Contributor
timestamp: December 07, 2013, 08:28:53 pm
content: Thanks for this thread. I found the cheapest on ebay with cal cert, battery, etc. to be just £11. But they will not ship to the UK, my guess being HMRC customs have been targeting that particular seller for the Lion battery. So cheapest I found was £12.73. With paypal $/£ rate extortion it ends up at £13.15 delivered.Wish me luck! I did ask for a certificate, we shall see.

author: Fraser
author_rank: Super Contributor
timestamp: December 08, 2013, 12:56:03 am
content: The lithium batteries were being targeted at the source post offices but I suppose the UK postal service may have been identifying them as well. If so I would expect the RM to advise the addressee though. I had a total of two go missing in transit.An option is to have them shipped without the battery and then fit your own. I have a box full of such mobile phone batteries if needed

author: Monkeh
author_rank: Super Contributor
timestamp: December 08, 2013, 05:11:56 am
content: Quote from: staxquad on December 05, 2013, 03:06:05 amWhat's the IC on that?

author: staxquad
author_rank: Frequent Contributor
timestamp: December 09, 2013, 12:27:04 am
content: Quote from: Monkeh on December 08, 2013, 05:11:56 amthe miniusb charging IC is the TP4056http://dlnmh9ip6v2uc.cloudfront.net/datasheets/Prototyping/TP4056.pdfthe VoltRef onboard charging IC is the UN8HXhttp://www.rcgroups.com/forums/showatt.php?attachmentid=5602321

author: Mr Smiley
author_rank: Frequent Contributor
timestamp: December 12, 2013, 04:04:45 pm
content: Mine has gone suicidal, it's now on top of the Christmas tree as the main lighting display in the window. People are knocking asking where i got it fromWon't turn on from the switch, all leds flashing together randomly, battery charges to 4.1v, when it does take it's medicine and turns on, only stays on a few minutes and then starts its light displayAnybody sketched out the circuit or had the same problems.Seller sending a replacement

author: Fraser
author_rank: Super Contributor
timestamp: December 12, 2013, 05:08:19 pm
content: I would always suspect the lithium battery as it may even be a recycled or poor quality item. Try running the unit with a lab power supply providing power instead of the lithium battery (not via the charging circuit but direct to the battery input.

author: Mr Smiley
author_rank: Frequent Contributor
timestamp: December 12, 2013, 09:55:36 pm
content: Hi,Tried a stable bench supply in place of the lith bat, got absolutely bugger all from it, wouldn't turn on, didn't do it's Xmas lights display, nowtleft it for a few hoursThought I’d buggered it completely.So i put it all together and it was still as dead as a dodo.Through curiosity, i connected 5v to the power socket and it came back to lifeSo i took it apart again, disconnected the battery, connected my supply and it went into Xmas light mode. So i disconnected the supply and reconnected it, it went into bugger all mode again.Reconnected battery, nowt, connected 5v and it came back to life in Xmas mode.The bat is dated 2009I did find thisAD584LH control board power supply is provided by a lithium battery and can charge the external DC power supply for use, charging UN8HX (5-pin SOT23 package H1JC UN8HX 54B4 H1IE) for lithium flow charge management IC, UN8HX is a constant current / constant voltage charging mode linear single lithium-ion battery charger IC, the charging current up 800m A, UN8HX features include current monitor, undervoltage shutdown, automatic recharge, charge termination status indication and input power is present. 8205A Dual N-Channel MOSFET is used as the lithium protection. Boost the MC34063 (DC-DC switching converter IC), 220uF16V and 101 inductive coils, the main battery (3.7V) voltage increase, the supply voltage to AD584LH purposes. Voltage reference is provided by AD584LH, and 8-pin IC next??guess is used to select a different voltage output.fromhttp://translate.google.com/translate?sl=auto&tl=en&js=n&prev=_t&hl=en&ie=UTF-8&u=http%3A%2F%2Fbugworkshop.blogspot.co.uk%2F2012%2F03%2Fad584lh-ad584lh.htmlIt looks like i have to go on the other side of the Dual N-Channel MOSFET, haven’t got a schematic and don't know what doing that will do

author: Fraser
author_rank: Super Contributor
timestamp: December 12, 2013, 10:21:56 pm
content: Ahhhh, I don't play with Li-Ion charge and management circuits so missed the possibility that the power supply in the unit expects to see a Li-Ion battery. A bench power supply obviously looks different to the lithium battery. No Li-Ion battery, no workyIf its worth your time, you could look for the main power rail that supplies the logic and reference and apply power there (with the Li-Ion battery removed and the normal supply path disconnected) If it works OK, your power management circuit or battery is sick.P.S. 2009 is old for a Lithium Ion battery that is supposedly 'new' so its either NOS or recycled from a mobile phone.

author: Mr Smiley
author_rank: Frequent Contributor
timestamp: December 13, 2013, 07:10:49 pm
content: Hi,For all you budding reference ownersGet out your eye glass, or magnifying glass or microscope and have a look at the track on the outer edge/corner of the pcb, on the same side but opposite the 5v charging socket, it can be seen through the top perspexAround where the 10.0v led is positionedAlso looks like problem solved

author: mtdoc
author_rank: Super Contributor
timestamp: December 22, 2013, 01:08:04 am
content: Got one of these today from ebay seller kuyaya520 - looks good but no "calibration certificate" with it

author: Macbeth
author_rank: Super Contributor
timestamp: December 23, 2013, 04:28:13 pm
content: Just got mine today, quite quick considering. Came with perspex case, feet, battery and cal certificate. Unusually mine came from Malaysia. I normal get stuff from HK/China.Seller luzhaokao (luchaokao)Seems to work, but got nothing with beyond 2 decimal places accuracy to test it with!

author: London Lad
author_rank: Regular Contributor
timestamp: December 23, 2013, 07:45:37 pm
content: Quote from: Macbeth on December 23, 2013, 04:28:13 pmDo you have a link to this seller please?

author: leppie
author_rank: Frequent Contributor
timestamp: December 24, 2013, 05:07:58 am
content: Got mine (w 'cert' and battery) from HK.US$18.41Seller: lck_led_com (ebay)Be careful not to short out the chip below the banana socket as I did by just sticking my multimeter probes inThought I killed it in 2 minutes, but plugging in a power source 'reset' it (all led's flash) and is was working fine again

author: staxquad
author_rank: Frequent Contributor
timestamp: December 25, 2013, 06:11:36 am
content: Quote from: leppie on December 24, 2013, 05:07:58 amBad implementation of a banana socket, allows the plug or probes to make contact with the circuit.The chip below the banana socket is the charging IC TP4056. Mine doesn't charge anymore using the 5v jack, now use the USB charging module.Replaced the banana sockets with ones where the plugs don't make contact with the circuit and has holes for multimeter probes, the tops tighten. A small form factor that allows self destruct defeats itself. Used the same spacers that sandwich the case and had some old sockets that squeezed in, ground down just a bit of the bolt and nut to make sure there was full clearance.

author: Macbeth
author_rank: Super Contributor
timestamp: December 26, 2013, 02:46:26 am
content: Quote from: London Lad on December 23, 2013, 07:45:37 pmHiya, the luzhakao seller was printed on the package, also the Malaysia Post thing. But looking at it, the item was scanned in China as it had a Chinese airport barcode on it. Going back to ebay, it was indeed sent from China/HK, by seller moncsshttp://www.ebay.co.uk/itm/181235948445. What can I say? Fu Manchu knows how to get around customs to get Lion Batteries through, the wily crafty chinese bastard! haha.Bargain too!Ok, my best meter is the VC99 which Dave would call me adickheadfor, but I don't have the luxury of ever working with HP/Agilent stuff my rich corporate overlord can buy at whim.Dave doesn't understand how thermocouples work, at least if you go on his bashing of the VC99 and his amazement the thing reads temperature even without a probe connected in his cheap multimeter showdown. Doh! I got this down to 18 degrees tonight. No K-type connected. (Because they work by measuring a known hysterisis of tiny voltages of bi-metals difference between two known temperatures, an on board temp is required for reference, as close to the bi-metal as possible, doh!)(However, I am sure Dave explains just this on another EEVblog)Let's check that 2.5000vSorry about all the filth on my desk, check out that 5.000Ok, to make this more exciting I decided to put my sig gen and scope on while measuring 7.500And finally, 10.000Amazingly, I didn't die. My 1000V CAT II meter survived and at worst is 2 counts out on 10V. I can now recalibrate it using this reference I am sure.Finally, some pics of the reference, and the chinese cal that appears to have been done on an Agilent 34401A at 18 celsius.(Sorry about the flash)O0 Haha, WTF? Afro? O0

author: Fraser
author_rank: Super Contributor
timestamp: December 26, 2013, 12:48:19 pm
content: @MacbethGlad you got your reference OK.I lived in Australia for several years and I can assure you that if I had called an Aussie the 'C' word, I would have had my face rearranged. Its a pretty ugly word no matter what context. Please also be aware that we have members of the female gender on this forum.

author: Macbeth
author_rank: Super Contributor
timestamp: December 26, 2013, 02:10:12 pm
content: Quote from: Aurora on December 26, 2013, 12:48:19 pmA bit too much Xmas Spirit went to my head. I have deleted the offending and apologise.

author: Co6aka
author_rank: Unknown
timestamp: January 08, 2014, 10:47:51 pm
content: A friend and I checked and have each confirmed an "issue" with these Chinese references: On each of our references there is about 100mV Pk-Pk digital noise on the output, at least according to his and my scopes. Looks like the bypassing and noise filtering could be better, and perhaps is a trivial fix. Maybe the rest of you can check your units as well.FWIW, on the 2.5V and 5V ranges mine works perfectly, but on the 7.5Vand 10V ranges there's problem (the voltage ramps up over several minutes to approximately the "calibrated" voltage, and then is somewhat unstable.) Anyway, MOST-AMUSINGLY, on the 5V range mine is "calibrated" at 4.99892V (@21'C) and my Rigol DM3068 measures the voltage as 4.99892V (@20.5'C.) On the 2.5V range, mine is cal'ed at 2.49955V and the DM3068 measures 2.49954V. On both ranges, the last digit of the DM3068 occasionally toggles one count to the low side. (Both the reference and DM3068 were powered on for about 8 hours in a reasonably temperature stable environment.)

author: London Lad
author_rank: Regular Contributor
timestamp: January 08, 2014, 11:17:50 pm
content: Why is that amusing ? Am I missing something?

author: markman
author_rank: Contributor
timestamp: January 11, 2014, 10:23:44 pm
content: I bought one from Franky and it arrived yesterday and I put a 1000mAh Samsung cell phone battery in it.Got to do something about those output connectors. Eech!Current drain operating: 15-16mA (slight higher when 10V output is selected)Current drain standby: about 3uAThe cal card listed 23C. I'm not sure exactly what the lab temperature was where I checked it out, but it's generally around 23-24C. Both 3458A's were autocal'ed immediately before these measurements and the AD584 module had been powered for hours. The last digit of the 3458's is a bit of a guess, especially on the higher voltage readings. The 34702 has a "do not calibrate" sticker on it from 1997, but the others are calibrated.Cal Card : 2.50029 5.00079 7.50044 10.000203458A #1: 2.500289 5.000803 7.500470 10.0002653458A #2: 2.500295 5.000816 7.500490 10.00028534401A: 2.5003 5.0008 7.5005 10.000334702: 2.500 5.000 7.499 10.000For a really precise circuit, the MC34063 puts out some glitches at 19KHz throughout everything, but it seems like the results are fairly good anyway. I'm curious how these will age.

author: wilheldp
author_rank: Regular Contributor
timestamp: January 12, 2014, 12:40:28 am
content: Does Franky have these listed in his store, or did you just contact him directly? If they are on his store, do you have a link?

author: markman
author_rank: Contributor
timestamp: January 12, 2014, 01:13:49 am
content: Somewhere back in the thread, I think Franky mentioned having them, even though they aren't listed. We handled it through PM. Be warned that some sellers are having trouble shipping these out of HK because of the batteries. Franky sends them without the battery.

author: wilheldp
author_rank: Regular Contributor
timestamp: January 12, 2014, 01:31:42 am
content: Right-o. Thanks. I will probably be getting some test lead stuff from Franky in the near future, so I will PM him and ask about the voltage standards then. No battery isn't a problem for me. It's certainly not a deal-breaker.

author: SeanB
author_rank: Super Contributor
timestamp: January 12, 2014, 11:12:31 am
content: He has got them, and removes the batteries before sending. You just need to go and buy a new clone Nokia BL-4C battery ( or whatever, these were the cheapest I found at the OHL mall) and solder it in when it arrives, then connect it to USB power to wake it up and charge the cell. Send him a PM for price and shipping along with delivery.My one is still somewhere in the ever so nice SAPO system, probably along with a few tons of other stuff. Delivery sometime this month or next month.Just remember that HK and PRC are closing for New Year on 31 January and will only be open in March. Good wishes for the year of the Horse. My birth animal.

author: Macbeth
author_rank: Super Contributor
timestamp: January 12, 2014, 06:00:27 pm
content: Quote from: SeanB on January 12, 2014, 11:12:31 amWTF? They get a whole month off for New Year? and we just get one day 01/01Surely you jest! Damn I will have to time my aliexpress and ebay purchases now!

author: London Lad
author_rank: Regular Contributor
timestamp: January 12, 2014, 06:27:15 pm
content: The postal services and big companies may close for Chinese new year but the small guys I deal with never close!!

author: SeanB
author_rank: Super Contributor
timestamp: January 12, 2014, 06:47:27 pm
content: Macbeth. They did work the whole Christmas time and this is the equivalent time now for them. Off till around 15 Feb then gradually they will ramp back to the normal frenetic pace.

author: don.r
author_rank: Frequent Contributor
timestamp: March 18, 2014, 02:25:49 am
content: Mine finally arrived and works as expected. Has a cal sticker too which, apparently was cal'ed against a 34401A according to the sticker. It came with a LiPo battery from eBay seller lck_led_com. I replaced the binding posts with ones with solid bottoms to prevent accidental shorting. One thing I did note is that after the battery has been charged, the blue LED that indicates charging retains a faint glow even with no power plugged in. I'll check it later to see if this is draining the battery significantly but I doubt it.Update: Overnight, the LED faded out but the unit remains operational. Must be a cap that is getting charged up and there is no bleed resistor for it.

author: darrylp
author_rank: Regular Contributor
timestamp: June 06, 2014, 03:40:25 pm
content: Just got one of these, and I'm not sure if its working as intended.basically, the battery is charged and a good capacity. I'm assuming with a charged battery, pressing and holding the button for approx 3 secnds should turn it on. However mine wont turn on unless its also got a 5V charge connection plugged in at the same time.so. if the 5V charge input is used, then the chrge light comes on, the four LED's light up for about a second, and then a 3 second push of the button turns on the output ( initially 2.5v )once its on, I can then remove the 5v charge supply and it stays on, and can cycle between outputs. and a 3 second push turns it off. but trying to turn it back on without the 5v supply it wont do anything.has anyone got a circuit or seen anything like this ? I'm guessing a bad connection ( as my board has terrible soldering ) or a faulty resistor or capacitor supplying the micro from the battery side, rather than the 5v charging side.thoughts as to where to look ? once its actually on, everything looks to be fine.help please !

author: Fraser
author_rank: Super Contributor
timestamp: June 06, 2014, 03:48:47 pm
content: This sounds like the same fault as another forum member described. Take a look back through this thread and I think you will find your answer. From memory it was a production fault. The PCB has a very thin track from the battery feed and it was open circuit. It just needs a thin wire to bridge the O/C PCB track.Aurora.Update:.... it was only 1 page backHere you go:https://www.eevblog.com/forum/beginners/t17704/msg346729/#msg346729Solution:https://www.eevblog.com/forum/beginners/t17704/msg347112/#msg347112

author: darrylp
author_rank: Regular Contributor
timestamp: June 07, 2014, 10:16:16 pm
content: Aurora Yes I had seen those posts, and no that track seems to be fine on mine. I will have to draw up the circuit at some point.Thanks for looking at my posy though.--Darryl

author: Mr Smiley
author_rank: Frequent Contributor
timestamp: June 08, 2014, 12:59:34 am
content: Hi,My problem was a faulty via, it wasn't open circuit, but the resistance changed as one wriggled the board, If i remember correctly it was connecting pin 1 of the micro to the positive supply,It's not here at the mo, but if you want i'll take a closer look at where i put a link

author: darrylp
author_rank: Regular Contributor
timestamp: June 10, 2014, 02:40:38 pm
content: Okay, seems to be related to pin 8 of the micro. ( is it a PIC ? ) pin 1 is battery voltage, but connecting the Lipo and before adding the 5v supply on the charger socket the grnd pin ( pin 8 ) reads 2.3 volts. Once hooked to charger it goes the battery grnd . if I jumper the battery grnd to the ground plane ( ie. I guess that area of my board has bad vias ) then I can turn on and off with only the lipo . ie no need for the charger to be used to "bootstrap it".Can someone with a charger internal battery confirm voltages on pin 1 & 8 of the micro before turning on please.Thank you--Darryl

author: Mr Smiley
author_rank: Frequent Contributor
timestamp: June 10, 2014, 05:49:16 pm
content: hi,The negative side of the battery connects to the 0v line through a mosfet, the long black smd device just under the black output socket and to the right of the charging chip; the one with 4 pins on the top and bottom shorter sides, this is part of the under-voltage battery protection. if the mosfet isn't being turned on then you won't get a ground connection to the rest of the circuitMy link went between pin 1 of the micro and the B+ connection to the left of the charging led.

author: darrylp
author_rank: Regular Contributor
timestamp: June 11, 2014, 09:40:35 am
content: Quote from: Mr Smiley on June 10, 2014, 05:49:16 pmokay, got it, have taken a look at the DW01plus datasheet and also a Phillips SA57608 datasheet.the sample circuit shows for the phillips part a bypass cap 0.1u from the voltage monitor ( charge sense ) pin to the chips GND pin.the DW01 doesn't have this and I'm thinking for the initial hookup to the battery ( mine came without one ), I'm wondering why the circuit doesn't power up properly without either a kick start charger port voltage, or a bypass of the GND ( over discharge control pin breaking the GND supply MOSFET and thus the full grnd plane ) . So would a cap help ? by pulling the CS ( VM ) pin low initially on powerup to the battery ?thoughts

author: Mr. Scram
author_rank: Super Contributor
timestamp: October 24, 2017, 09:39:13 pm
content: Can anyone tell me the capacity and dimensions of the battery pack? Due to shipping restrictions, I received one without a battery and I don't have anything suitable around.

author: iainwhite
author_rank: Unknown
timestamp: October 26, 2017, 09:29:52 pm
content: Quote from: Mr. Scram on October 24, 2017, 09:39:13 pmTook a screenshot of a Scullcom video about the same/similar reference - hope it helps

author: Mr. Scram
author_rank: Super Contributor
timestamp: October 26, 2017, 09:37:20 pm
content: Quote from: iainwhite on October 26, 2017, 09:29:52 pmYes, that does help meI can't quite find the dimensions of this model, but having the capacity at least gives a decent ballpark figure. Thanks!

author: iainwhite
author_rank: Unknown
timestamp: October 26, 2017, 09:46:31 pm
content: Also, earlier in the thread, SeanB mentions using a clone Nokia BL-4C battery...

author: voltlog
author_rank: Regular Contributor
timestamp: February 13, 2018, 05:02:12 pm
content: I am looking to get one of these voltage references based on the AD584 from aliexpress but looking closer at the product pictures I can see the can marked as AD584LN. Is that possible? because by looking at the datasheet I see the can version should be ending in H and the plastic package should be ending in N. This makes me think the guys making these could be re-marking these as an L version when in fact they are not L grade?

author: Mr. Scram
author_rank: Super Contributor
timestamp: February 13, 2018, 05:10:02 pm
content: Quote from: voltlog on February 13, 2018, 05:02:12 pmI would make sure to contact the seller before buying. Without it being specified, you could receive any version.

author: voltlog
author_rank: Regular Contributor
timestamp: February 13, 2018, 09:56:29 pm
content: Quote from: Mr. Scram on February 13, 2018, 05:10:02 pmQuestions have been sent but until I get a reply (It's Chinese New Year so it might take a while) I would like to hear your opinion on the LN part number.

author: Bzzz
author_rank: Contributor
timestamp: October 25, 2023, 10:32:18 am
content: Quote from: Mr Smiley on December 12, 2013, 09:55:36 pmWell, I just forcibly shut down my unit by ripping off the metal cap of an old spring-loaded 4mm plug at work (SKS Hirschmann BUELA - Bueller, Bueller?), which shorted out something. No visible damage, no magic smoke, but wouldn't turn back on. After some investigation I of course ended up here, looking for some schematics around the soft-power-on circuit, but simply connecting it to 5V did the trick. Apparently the unit cannot do a black start with the built-in lithium cell, but instead relies on some aux power to get its control circuit up, and then stays on permanently with extremely low power consumption. Well, it's working just fine again - 2.5V rail for example is 2.49888V on calibrated 6½ digit Keysight gear now (not warmed up for three moons!) and was marked as 2.49887V at least 10, maybe 15 years ago when I bought it. The badly scratched AD584LH has an 9118 date code...

author: Neshco
author_rank: Contributor
timestamp: March 04, 2024, 01:00:50 pm
content: Looking into this to buy one, and found that there are only KH versions of the IC.What is the story with it, is it the L version somehow rebranded or...?