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?'
Mine arrived a couple of days ago. Need to find the right connector to charge them.
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
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'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
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.
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.
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.
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..
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
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
Quite positive they are sixes.... (as in 99% positive unless someone has a awfully weird 4)
Don't be so sure - That must be a Chinese 4
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.
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
Looks like my label was written by the same guy:
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.
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
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
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.
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
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
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'