I vote to correct both. It could be the same challenge. If the voltage monitor circuit uses a resistor voltage divider circuit to drop the input voltage to the range of the AD converter, the resistors should be 1%, not the 10% (or 20% if cheap) accuracy type. And it only needs to be the two resistors in the voltage ladder. The rest can usually be 10% without problems.So it's a useless feature.
I vote to remove the voltage monitor and invest in decent electrolytic caps! (snip)
If it is the same challenge, then it is a challenge of design skill. It would be quite concerning if 10% resistors were used unless there were a calibration routine. Assuming stability over temperature, resistor tolerance errors can be easily cal'd out.I vote to correct both. It could be the same challenge. If the voltage monitor circuit uses a resistor voltage divider circuit to drop the input voltage to the range of the AD converter, the resistors should be 1%, not the 10% (or 20% if cheap) accuracy type. And it only needs to be the two resistors in the voltage ladder. The rest can usually be 10% without problems.
That would be ratio plus offset. The last post in that thread.A zener is not precise and would require a calibration.
There are precision reference devices specifically for this purpose.
Also, the simple ratio shown in the other post may not work. After all y = mx + b.
If b is non-zero it needs to be accounted for.
Then why does the voltage show in tenths of a volt? That was a waste of time and programming. I need a voltage on the input. So you feel that 9 volts is ok as an input, as long as the voltage reading show 10.5 volts?You can easily tell apart 12, 18, 24 and 48. that's the basic functionality needed for a routerboard. costs would increase if we would make more fancy stuff. I guess you don't want the other feature of Juniper (price).
There you go, chariebrown! I'd pay that!(snip) And if price is the "issue" then slap another letter on the end of the RB names and charge $10 more for it. Its not exactly rocket science. (snip)
Precision is not a word I would use in this thread I think its pretty clear from the posts here that RB's often dont report anywhere near the correct voltage (No 1-2v out is not acceptable)I will find out the actual precision of this and will post back here.
Can you give us some numbers? I.e you were seeing upto 20% different between read and actual voltage in 4.9 and only 6% with 4.11?In recent RouterOS versions, we have changed the formula of calculation, and it's more precise (in v4.11 exactly), as each device has it's own components, in the mentioned version we now use different calculation system for each routerboard model specifically. you will see improvement from say v4.9 to v4.11
please don't, there is already too many of themAlso going to start another thread about changelog's