hv probe

[m3vuv]

I assume its so it doesent load the dut and drag the voltage down,like a x10 scope probe principal?

[tggzzz]

Well,looks like i have sorted it as near as  dam it,swapped and experimented with resistor r2,after a few trys i finished up with r2 at 1.235mohm,on the 240v ac mains  measured without the probe i read 241.8v on my meter ac,with the probe attached i get a reading of 239.7v ac,measuring the anode voltage of my yaseau fl2100z i read 245v,it should read 240 in an ideal world ie x10,its within 50v at 2.4kv,thats near enough for what i need,73 m3vuv.

Now you should read, understand and apply this bit of the upcoming TAoE X-Chapters book: https://www.dropbox.com/s/dli62uyuldr7z5q/1x.2_Resistors_DRAFT.pdf?dl=1  Sections 1x.2.3 and 1x.2.7 are directly relevant.

[m3vuv]

I have  an avo8 ordered that should be here today,i will do some back to back comparisons with that and post the results!

[John_BS]

HV probe design is problematic, not because an understanding of ohms law is in order, but for two primary factors: one  obvious, one obscure.
1. Basic safety around voltages in excess of a few hundred volts
2. The voltage coefficient of many resistors is either not specified, or is hard to find. Unhelpfully, the voltage coefficient is generally higher for higher value resistors.  The errors introduced mean that acheiving 0.1% precision is non-trivial, and requires careful selection of resistors.  Calibration at lower voltages leads to a false sense of precision.
In this instance we are perhaps concerned with more fundamental problems.