Morning all!
I love my NanoVNA-H4. it JUST NOW probably has saved me from really screwing something up.
My local club has a MFJ-259 analyzer. that we know is way out of wack. it needs re calibration.
I found online a complex and very through calibration ummmm, how to do it.
it as a part needs some pure non-inductive restive loads.
12.5, 50, 75, 100, 200 ohms. and OPEN as well as SHORT.
I found online some nice amphanol pl-259's
and a set of precision resistors. It did not say if they were pure carbon or inductive.
Well I'm thinking they are inductive in some way.
I used a DVM,? actually 3 of them, to pick out perfect dead on resistive values for each load and soldered them into the P-259's
After soldering I again re measured with the DVM's the values and are dead on!
So went to do the calibration of the MFJ unit and when i attached each load. NONE were even close resistance wise in the display! I know this thing was out of alignment, but wow!
Then I got to think hmmmm whats the VNA say these loads are?
And WOW! It agrees with the MFJ.
the "50" ohm comes in like 80,,? the 200 is like 160,, etc. NONE are even close.
I did not make a note of the inductance if any, but suspect that is what is happening.
so anyone know of a place with resonable price loads in pl-259 format?
OR resistors that are for sure non inductive? so I can make my own again?
Joe WB9SBD
