Got to be woth £20 uk

[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