problem after a measure of a capacitor charge!!

[alexmarines]

thx for understood my problem with the english!!  lol

ok now it's clear...when i will come back i will do these steps!1

thx for all mike!!!

[support]

  my Italian is much wore than your English.
Let us know about result...

[alexmarines]

mike i have done all the steps following you last post but it seems that device doesn't write the value in the eprom...now i explain to you all the steps..

i switched on the device
i put a resistor 10 ohms and the device read 11.7 ohm
i tune r15 until i read 10 ohm and switched off the device
i put a wire in the device and switched on the device for calibration and after i read "cal done".
i put a resistor of 0.49ohm and the device read 0.33ohm then i tune r15 until i read 0.49 ohm.
i switched off the device.
i put a wire in the device and switched on the device for calibration and after i read cal done.
i put a resistor of 0.60ohm and the device read 0.50 ohm then i tune r15 until i read 0.60 ohm.
i switched off the device.
i put a wire in the device and switched on the device for calibration and after i read cal done.
i put a resistor of 0.80ohm and the device read 0.78 ohm then i tune r15 until i read 0.80 ohm.
i switched off the device.

now i do again the calibration with the wire and after i tried to read all the value of the low resistor.
i put again the resistor of 0,49 ohm and i read again 0.33 ohm!!! then the value that i  tuned before didn't write in the eprom!
the same for the other resistors!!
it seems it doesn't write in the eprom!
for confirm i put the resistor 10 ohm and the device read 11.7 ohm again!!!

did you understand the problem?
it seems the device doesn't write the value in the eprom because when i tune r15 for other resistor it lost the last tune i  did.

i hope you have understood the problem.

sorry again for my english!!

[support]

Ohhh Alex, it seems I understand problem now...
In this case probably VT2 needs to be replaced (IRLML6402)
Sometimes these transistors are "hard to get" 
You can try to tune R15 to provide maximal precision in main range (0...1 ohm)
Just DON'T PAY ATTENTION for precision for 10 ohms and more...
The same way as you did "tune-calibr-check"....

[alexmarines]

i am happy you have understood the problem.

can you tell me how to test this component?
so i can assure it is damaged.
is this the correct datasheet:   http://www.irf.com/product-info/datasheets/data/irlml6402.pdf   ?
is it a transistor?

i found it on italian store!!!!  :-)

http://it.rs-online.com/web/p/mosfet/0301322/?searchTerm=IRLML6402&relevancy-data=636F3D3226696E3D4931384E4B6E6F776E41734D504E266C753D6974266D6D3D6D61746368616C6C7061727469616C26706D3D5E5C772B2426706F3D313326736E3D592673743D4D414E5F504152545F4E554D424552267573743D49524C4D4C363430322677633D424F544826

can you confirm it's the component i found?
do you think i need others components?

[support]

yes. here it is! need to start from it as more likely cause..

[alexmarines]

i have changed the transistor!!!
when i will come back at home i will try to tune the device!
i hope i will solve the problem...

stay tuned ;-)

[alexmarines]

nothing!  :-(

always the same problem!!

[support]

hmm... even don't know what to say...
we can send you assembled pcb. let it cost 40usd including shipping cost

[alexmarines]

hi mike,

but without the lcd display?
only the pcb?

[support]

hi mike,

but without the lcd display?
only the pcb?

as you want 
we have fully biult ones (with LCD)

[alexmarines]

for 40usd..what do you send me?
the assembled pcb with lcd and probes?

[support]

for 40usd..what do you send me?
the assembled pcb with lcd and probes?

with LCD and without probes. just replace your pcb with new one

[alexmarines]

then i have to put only my probes and my covers.
is it correct?

[support]

ABSOLUTELY!