Could you please repeat the Zener test (with a Zener <10V and another one >10V) and measure Vcc (5V) with a DMM? Is Vcc stable?
However the issue persists: 1. Zener diodes over 10 V are measured perfectly, below 10 V(or thereabout) are shown as ~1/4th of their voltage.
Please be aware that this is NOT A FIRMWARE ISSUE, since it had a similar behaviour with the original Chinese firmware.
However the issue persists: 1. Zener diodes over 10 V are measured perfectly, below 10 V(or thereabout) are shown as ~1/4th of their voltage.
Please be aware that this is NOT A FIRMWARE ISSUE, since it had a similar behaviour with the original Chinese firmware.In this case, show us the compiled firmware and the configuration files you used.
It will also be nice if you show the results of hardware tests T1-T6 from the Selftest item.
Second archieve has screenshots of each stage of Self Test, as well as the Show Values screen.
Sorry about the mess on the desk! See attached measurement of an 8.2 V Zener with the dmm over the diode.One with the dmm over the VCC.
Another with a 16 V Zener. And one with empty test terminals.
I can put a trace scope on the VCC if needed, but it looks pretty steady.
I completely forgot one more thing. Such poor readings in the T2-T3 tests can be caused by a faulty SRV05-4 protective assembly. Remove it for a while and repeat the hardware tests again.
No luck with the DZ1 chip removed, I'm afraid! Re-did the tests, similar results.
ha ha, well I now have gone from zero testers a month ago to two and another currently on a plane. Then I bought six resistors for $2.57 each and six for $1.60 each to "fix up the kits" Along with a couple of precision voltage regulators and a couple of precision voltage references.
Wow, that's expensive! A local online shop sells 0.1% TH resistors (Yageo) in single quantity for around EUR 0.25 - 0.30 (680 and 470k are 0.27).
They look pretty identical...
I could never get the Test Button to operate properly via the U3(as in my board) chip. I re-programmed it as stated, but could not get it to go low on pin8(i.e. PD2 on the MCU).
... no idea what to do yet.
Why is the AREF pin connected to GND via a capacitor(and not directly, or via dc ref)?
oitar,it would be nice if you made a short video showing the process of turning on the tester and the self-test procedure. Only with the condition of using very short jumpers to short the ZIF 1-2-3 test contacts.
I would also like to see what fuses are currently installed for your chip? Exactly those that are now being read from your chip.Why is the AREF pin connected to GND via a capacitor(and not directly, or via dc ref)?
Indman, thank you for your help!
I made a video, including Start-up, Test, Adjustment, 2 zeners test, and Fuse-read. I is almost 5 min long, and about 11 MB after recoding.
Couldn't upload it here, due to the 4 MB limit, please check the link to my GDrive. Otherwise let me know if I should cut it to 3 pieces maybe.
https://drive.google.com/file/d/1_b-A_LHtR5gFB1j11Iy09tIkvR9vuGX2/view?usp=sharing
Have the test results not changed at all, exactly the same as before?
They look pretty identical...
Thanks, I will try removing the OV protection.
With the battery back, and Self Test performed(all T readings are basically the same), the zener/resistor issue is still present.
The fuses are now exactly as you suggested. I made a number of Test/Adjustments, no improvement on the displayed results. Should I make a new video?
What will be the results when measuring zener diodes from the "Zener" menu item?
This pretty much confirms that I have a damaged/defective ADC then?
What will be the results when measuring zener diodes from the "Zener" menu item?You didn't answer this question.
Show me a photo of the clone from the details side of how it looks at this point in time.