You may not have understood the idea I was trying to convey.?
Most forum members know about placing D2 on the board to allow battery voltage monitoring.?
I want to take it one step further. Since you will damage the uP with any voltage that exceeds its max input rating, a x10 attenuator with external leads at pin 1 of the uP will allow it to act as a DC voltmeter.?
So, instead of measuring the internal battery with a max input of 4.2v, the attenuator will allow an external DC input of up to 42VDC (theoretically).?
Of course, you'd be crazy to apply that to the input but for measuring voltage on a tower mounted RF amp and only need to take the nanoVNA with you - I think that idea might not be so far fetched.?
I'll prototype it and report back with the results.?
Larry
On Fri, 11 Oct 2019 at 6:20 PM, DMR<bryonikater@...> wrote: No resistors are required, a diode with a voltage drop of 600, 620 millivolts must be installed. Since the D2 diode has already been installed, no modifications are needed.
I thought it necessary to add a battery voltmeter, as I want to see more accurate information.
The firmware is based on the latest changes of the edy555. Also, it has a virtual keyboard that does not hang, + meter measurement to hundredths of a meter when measuring short cables.
