Got to be woth £20 uk

[Telequipment]

http://www.ebay.co.uk/itm/171016345011?_trksid=p5197.c0.m619

[Anks]

"High Precision" and china don't normally go together but you never know.

[Telequipment]

"High Precision" and china don't normally go together but you never know.

I 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

[mikeselectricstuff]

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?

[madires]

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. 

[Galaxyrise]

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.)

[npelov]

@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.

[amyk]

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.

Does 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.

[Smithy]

What about one these instead...

http://shop.voltagestandard.com/product.sc;jsessionid=A1327A2186B7A7DAF0AB2221726E5D50.m1plqscsfapp01?productId=3&categoryId=1

[madires]

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.

Does 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.

It's not in the Rev C datasheet but in the older Rev A. The differences are:

OUTPUT VOLTAGE TOLERANCE
Maximum Error1 for Nominal
Outputs of:
10.000 V   +/- 5mV
7.500 V     +/- 4mV
5.000 V     +/- 3mV
2.500 V     +/- 2.5mV

OUTPUT VOLTAGE CHANGE
Maximum Deviation from +25°C
Value, TMIN to TMAX2
10.000 V, 7.500 V, 5.000 V Outputs      5 ppm/°C
2.500 V Output                                    10 ppm/°C

But I guess that the AD584LH isn't produced anymore.

[iloveelectronics]

Martin just had a quick look at this device:

Jump to around 22:04 to see his first look review.

[madires]

Martin just had a quick look at this device.
Jump to around 22:04 to see his first look review.

Looks 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.

[Fraser]

GBP20 is the average cost of an evening in the pub so I just stayed in this evening and ordered one 

[Bored@Work]

GBP20 is the average cost of an evening in the pub so I just stayed in this evening and ordered one 

Are 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.

[Fraser]

No mention of certificate but I can check it against a recently calibrated lab meter so can produce my own calibration table 

[KJDS]

GBP20 is the average cost of an evening in the pub so I just stayed in this evening and ordered one 

I've regularly had rounds that cost three times more than that. I probably need slightly less drunkardly friends.

[Fraser]

 

[807]

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.l2649

No mention of a certificate on any of the Ebay listings though.

[staxquad]

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.l2649

No mention of a certificate on any of the Ebay listings though.

even 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=item3381329774




They 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. 

[iloveelectronics]

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

[Stonent]

Appears to be powered by a Samsung GT-i9000 battery

[poorchava]

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...

[Stonent]

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 says

The MCU switch 4-way reference voltage output with LED indicators

So some kind of Microcontroller?  That T1 chip looks suspicious. Pin 8 appears to be grounded, it could be a PIC12 series?

[madires]

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 says

The MCU switch 4-way reference voltage output with LED indicators

So some kind of Microcontroller?  That T1 chip looks suspicious. Pin 8 appears to be grounded, it could be a PIC12 series?

There 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.

[Fraser]

My voltage reference unit arrived today from this seller:

http://www.ebay.co.uk/itm/400452242651?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1497.l2649

GBP16.10

Ordered from Hong Kong on 22 June, arrived with me in the UK 27 June.... pretty good service 


My 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 produce  Otherwise I will use it as a voltage reference to build a simple current reference add-on. GBP16 well spent.

Picture attached

I 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.

[807]

My voltage reference unit arrived today from this seller:

http://www.ebay.co.uk/itm/400452242651?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1497.l2649

GBP16.10

Ordered on 22 June arrive in UK 27 June  ...

WOW. Just 5 days from Hong Kong!

I placed my order with the same seller on 15th June. Still waiting!

[Fraser]

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.

[807]

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.

[Fraser]

Good point. I have removed my comment in case they decide to change their price !

Cheers

Fraser

[G7PSK]

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.

[Fraser]

My second unit from this supplier is already in the post to me....nice fast despatch 

I 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 :

2.50093V
5.00165V
7.50336V
10.00360V

My old Uni-T UT39A gave the following readings:

2.48V
4.96V
7.45V
9.93V

Another old meter...the Wavetek DM23XT manual ranging:

2.50V
5.01V
7.52V
10.02V

Old Wavetek DM73A Probe meter:

2.504V
4.99V
7.49V
9.99V

My Fluke 87 III readings:

3.5 Digit mode:

2.500V
5.00V
7.50V
10.00V

4.5 Digit mode:

2.501V
5.002V
7.503V
10.004V

A 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 

[ttp]

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...

Look at datasheet, you apply low or high to few pins and output voltage changes, all precision magic is done inside the chip.

[807]

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 

[peter.mitchell]

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.

[Telequipment]

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 

It 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.

[807]

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.

[Telequipment]

 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.

[Fraser]

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.

[807]

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!

[Fraser]

X-Ray safety scans ?

[807]

X-Ray safety scans ?

Hmm..possibly.

Perhaps the sellers should wrap the whole unit in bacofoil. 

[iloveelectronics]

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!

If 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.

[Fraser]

Bacofoil = Aluminium = transparent to X-Ray due to very low density 

[Telequipment]

Just ordered one. , guess that will be around a month

[Fraser]

I don't think you will be disappointed 

[807]

Bacofoil = Aluminium = transparent to X-Ray due to very low density 

Oops!

Now where's that embarrassed emoticon? Ahh...here it is... LOL.

[amyk]

AFAIK they are still allowed by sea and land, so you can still get them, it'll just take a lot longer...

[madires]

AFAIK they are still allowed by sea and land, so you can still get them, it'll just take a lot longer...

... 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

[G7PSK]

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.

[M. András]

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

[bilko]

I ordered mine 27th June, still waiting

[pmcouto]

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 34461A
2.5 V     –     2.50033  V     –     2.50028 V
5 V        –     5.00240  V     –     5.00241 V
7.5 V     –     7.50129  V     –     7.50136 V
10 V        –   10.00285  V     –   10.00296 V

In my opinion, it is well worth 20 GBP! 

Regards,
Pedro Couto

[Fraser]

My additional two units that are travelling to the UK are very much overdue now 

I 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.

[G7PSK]

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.

[staxquad]

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 Canada
79% chance of arrival after 20 calender days for Canada
72% chance of arrival after 14 calender days for UK
92% chance of arrival after 20 calender days for UK


worth it with the calibration sheet

already did a mod to it to extend it's usefulness



with the calibration sheet in it, it won't be lost

[807]

...already did a mod to it to extend it's usefulness...

with the calibration sheet in it, it won't be lost

Yep. 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!

[Fraser]

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.

[M. András]

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)

[G7PSK]

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.

[Fraser]

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 China


My 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.

[G7PSK]

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.

[Fraser]

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 

[G7PSK]

Regulations are all well and fine until you get to the "jobsworth" thats when the trouble begins.

[ecat]

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.

The 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.

[Codemonkey]

The 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.

I 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).

[M. András]

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

[Nermash]

I just measured mine with Fluke 287 and it is 400uV noise on AC mV range. Are you charging it?

[M. András]

I just measured mine with Fluke 287 and it is 400uV noise on AC mV range. Are you charging it?

no its fully battery powered it was fully charged when arrived
edit: 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

[ecat]

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 #441

Edit:
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.

[alm]

A quick and dirty test:
Measured mV AC with a 4.5 digit handheld Fluke: 0.3 mV
DCV at 10V setting: stable 9.998 V reading

With 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).

[M. András]

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

[Fraser]

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 jobs  No surprise that my old Altai meters from the 1980's were bin jobs ! The AVO analogue meter was still reading accurate though 

[M0BSW]

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.

[KJDS]

I ordered a few last week, hopefully they won't take too long to turn up.

[G7PSK]

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.

[staxquad]

mine died

Tried 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-Po
All 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?'

[KJDS]

Mine arrived a couple of days ago. Need to find the right connector to charge them.

[M0BSW]

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

[KJDS]

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.

[M0BSW]

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.

I'm really looking forward to the AVO results, as I'm looking at one of these on ebay

[KJDS]

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 205
2.500               2.496               2.500                   2.500          2.499         2.499       2.498        2.506          2.498
5.004               5.00                  5.002                  5.00            5.00           5.00         4.95         5.01             4.99
7.504                7.49                 7.500                   7.50           7.49           7.50         7.45          7.52            7.49
10.007             9.99                 10.002                   10.00         9.99          10.00        9.98          10.03          9.99

and on three Keithley 2015THDs          HP3478A                   values on the certificate
2.49942        2.49940       2.49939       2.49940                     2.49946
5.00208        5.00204       5.00202        5.0020                     5.00211
7.50057        7.50050       7.50049        7.5004                     7.500591
10.00266      10.00257      10.00255     10.0025                     10.00266


Reference 2 was faulty, providing ever changing readings.

Reference 1 on the three keithleys and the HP3478A

 on three Keithley 2015THDs          HP3478A                   values on the certificate
2.49965       2.49964       2.49963       2.49965                     2.49971
5.00213        5.00210       5.00208        5.0021                     5.00218
7.50225       7.50220       7.50218        7.5022                     7.50230
10.00427      10.00420      10.00417     10.0042                     10.00430


Ref 3 on three Keithley 2015THDs          HP3478A                   values on the certificate
2.49861        2.49861       2.49860       2.49861                     2.49868
5.00140        5.00130       5.00136        5.0013                     5.00137
7.49879        7.49873       7.49871        7.4987                     7.49866
10.00113      10.00105      10.00102     10.0010                     10.00089


I'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.

[Fraser]

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.

[staxquad]

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 luck 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.

Printed 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.

[Noldir]

Got mine as well, the small sheets says:

2.500 = 2.69932
5.000 = 5.00118
7.500 = 7.69952
10.000 = 10.00096

Aren't the 2.5 and 7.5 values a bit...off? 0.2 is quite a bit of deviation..

[mianchen]

Got mine as well, the small sheets says:

2.500 = 2.69932
5.000 = 5.00118
7.500 = 7.69952
10.000 = 10.00096

Aren't the 2.5 and 7.5 values a bit...off? 0.2 is quite a bit of deviation..

are u sure the 6s are 6s not 4s?

Sent from Mars

[Fraser]

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

[Noldir]

Quite positive they are sixes.... (as in 99% positive unless someone has a awfully weird 4)

[Noldir]

Here's a piccie

[pmcouto]

Don't be so sure - That must be a Chinese 4 

[Kostas]

Here's a piccie

Look 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.

[KJDS]

Here's a piccie

Look 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.

I 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

[PA0PBZ]

Looks like my label was written by the same guy:

[Fraser]

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.

[Noldir]

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.

Ah yes, I'd almost forgot that he's not quite used to writing in western numerals 

And of course I'm quite forgiving of his style, he just put me on the wrong footing by his otherwise good handwriting

[Noldir]

Looks like my label was written by the same guy:

Yup, looks the same to me! And, looking at yours I can definitely see how that "6" could be a 4

[staxquad]

Looks like my label was written by the same guy:

For 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.

[iloveelectronics]

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

[Mr Smiley]

uncased £9.83

http://www.ebay.co.uk/itm/290994447231?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1438.l2649

cased £11.13

http://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

 

 

[iloveelectronics]

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

[mianchen]

Got mine today:

	Volt Ref	UT-61E	Fluke 87III(1)	Fluke 87III(2)	HP 3468A
2.500	2.49849	2.496	2.497	2.498	2.49817
5.000	5.00233	4.999	5.001	5.001	5.0018
7.500	7.49884	7.496	7.497	7.497	7.4980
10.000	10.00221	9.999	10.000	9.999	10.0012

My little uncalibrated DIY AD588JQ voltage ref gives "better" results 

	UT-61E	Fluke 87III(1)	Fluke 87III(2)	HP 3468A
5.000	4.998	4.999	5.000	5.0003
10.000	9.998	10.000	9.999	10.0007

Which one should I trust? I don't need high precision measurement, but it's kind of nice to know which reference is more 'real'

[Fraser]

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.

2.50000V
5.00000V
7.50000V
10.00000V

[alm]

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.

The Chinese unit is not calibrated.

Measuring 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.

A voltage standard should produce far more accurate voltages than these units

More 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.

[tmammela]

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.html you 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.

[Mr Smiley]

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.html you 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.

If 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 

[mianchen]

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

[Mr Smiley]

Hi,

Has anybody had one of these on long term test 

 

[ddrl46]

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.

[staxquad]

AU $1.00 upgrade to the Volt Ref

adding 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 pictures 





Durable 1PCS 5V Mini USB 1A Lithium Battery Charging Board Charger Module B98B
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=231099090848

[Mr Smiley]

Don't these units already have a lithium charger built in 

I can see the advantage of using a standard off the shelf usb lead 

ps, 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 

 

[KJDS]

Don't these units already have a lithium charger built in 

I can see the advantage of using a standard off the shelf usb lead 

ps, 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 

 

I'd put money on it being what ever temperature their thermometer is showing at the time

[mianchen]

Or check the weather forecast of Shenzhen before you order if you want a specific cal temp.

sent from Mars

[SeanB]

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.

[M0BSW]

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.

[Macbeth]

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.

[Fraser]

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 

[Monkeh]

AU $1.00 upgrade to the Volt Ref

adding mini USB recharging capability (rather than plugging in 5v from a wall adapter)

What's the IC on that?

[staxquad]

AU $1.00 upgrade to the Volt Ref

adding mini USB recharging capability (rather than plugging in 5v from a wall adapter)

What's the IC on that?

the miniusb charging IC is the TP4056 http://dlnmh9ip6v2uc.cloudfront.net/datasheets/Prototyping/TP4056.pdf

the VoltRef onboard charging IC is the UN8HX  http://www.rcgroups.com/forums/showatt.php?attachmentid=5602321

[Mr Smiley]

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 from 

Won'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 display 

Anybody sketched out the circuit or had the same problems.

Seller sending a replacement 

[Fraser]

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.

[Mr Smiley]

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, nowt  left it for a few hours 

Thought 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 life 

So 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 2009

I did find this

AD584LH 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.

from

http://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.html

It 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 
 


 

[Fraser]

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 worky 

If 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.

[Mr Smiley]

Hi,

For all you budding reference owners 

Get 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 perspex     

Around where the 10.0v led is positioned

Also looks like problem solved 

 

[mtdoc]

Got one of these today from ebay seller kuyaya520 - looks good but no  "calibration certificate"  with it 

[Macbeth]

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!

[London Lad]

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!

Do you have a link to this seller please?

[leppie]

Got mine (w 'cert' and battery) from HK.

US$18.41

Seller: 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 in 

Thought I killed it in 2 minutes, but plugging in a power source 'reset' it (all led's flash) and is was working fine again

[staxquad]

Got mine (w 'cert' and battery) from HK.

US$18.41

Seller: 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 in 

Thought I killed it in 2 minutes, but plugging in a power source 'reset' it (all led's flash) and is was working fine again

Bad 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.

[Macbeth]

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!

Do you have a link to this seller please?

Hiya, 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 moncss http://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 a dickhead for, 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 2.5000v



Sorry about all the filth on my desk, check out that 5.000



Ok, to make this more exciting I decided to put my sig gen and scope on while measuring 7.500



And finally, 10.000



Amazingly, 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 

[Fraser]

@Macbeth

Glad 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.

[Macbeth]

@Macbeth

Glad 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.

A bit too much Xmas Spirit went to my head. I have deleted the offending and apologise.

[Co6aka]

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.)

[London Lad]

Why is that amusing ? Am I missing something?

[markman]

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 3uA

The 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     10.00020
3458A #1:   2.500289  5.000803  7.500470   10.000265
3458A #2:   2.500295  5.000816  7.500490   10.000285
34401A:      2.5003      5.0008      7.5005        10.0003
34702:        2.500        5.000        7.499          10.000

For 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. 

[wilheldp]

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?

[markman]

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. 

[wilheldp]

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.

[SeanB]

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.

[Macbeth]

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.

WTF? They get a whole month off for New Year? and we just get one day 01/01 Surely you jest! Damn I will have to time my aliexpress and ebay purchases now!

[London Lad]

The postal services and big companies may close for Chinese new year but the small guys I deal with never close!!

[SeanB]

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.

[don.r]

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.

[darrylp]

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 !

[Fraser]

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 back  Here you go:

 https://www.eevblog.com/forum/beginners/t17704/msg346729/#msg346729

Solution  :

https://www.eevblog.com/forum/beginners/t17704/msg347112/#msg347112

[darrylp]

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

[Mr Smiley]

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 

 

[darrylp]

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

[Mr Smiley]

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 circuit 

My link went between pin 1 of the micro and the B+ connection to the left of the charging led.

 

[darrylp]

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 circuit 

My link went between pin 1 of the micro and the B+ connection to the left of the charging led.

 

okay, 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

[Mr. Scram]

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.

[iainwhite]

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.

Took a screenshot of a Scullcom video about the same/similar reference - hope it helps

[Mr. Scram]

Took a screenshot of a Scullcom video about the same/similar reference - hope it helps

Yes, that does help me I can't quite find the dimensions of this model, but having the capacity at least gives a decent ballpark figure. Thanks!

[iainwhite]

Also, earlier in the thread, SeanB mentions using a clone Nokia BL-4C battery...

[voltlog]

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?

[Mr. Scram]

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?

I would make sure to contact the seller before buying. Without it being specified, you could receive any version.

[voltlog]

I would make sure to contact the seller before buying. Without it being specified, you could receive any version.

Questions 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.

[Bzzz]

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, nowt  left it for a few hours 

Thought 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 life 

Well, 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...

[Neshco]

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...?