[R-390] Re: R390A meter movement current.

[DCrespy at aol.com]

On the 1 mA carrier meter: 
 
Looking for replacements over the years, I have found only original meters  
with 18 ohm internal resistance.  I have found several others at swaps and  
surplus houses, at about 38 ohms.  These work fine when compared side by  side 
with an original.  AGC seems to work well and the meter  deflection is identical 
in the side by side comparison.  They do take a  different zero set of 
course.  Some of the "international" brand 100 ohm  1mA meters have an internal 
series resistor, that when jumpered makes the meter  a 38 ohm movement.  So they 
are worth opening, so long as they are not the  glow in the dark versions.  
Note, when you open them, some of the  screw/bushings are left hand thread!
 
Good hunting!
 
Harry KG5LO
Saline MI