[R-390] R-390a meters

[mparkinson1]

How can you really test what the resistance is on the sub 1Ma meter?
I have several of them I did put it into the R-390a receiver to test it and it seems to work very well.
I compared it to the original meter watch both working at the same time and frequency and didn't see any difference.
But would like to know how to test the internal resistances of the movement.
thanks Matt.