[R-390] RE: Using Surplus Meters

[DCrespy at aol.com]

I got to know Tom Bowes a 5 or 6 years ago, when I bought one of the kits  in 
discussion right now.  Until about 2 years ago (?), I ran into him  regularly 
at swaps in the Detroit area.  I always enjoyed talking with  him.  Really 
decent guy!
 
Anyway, the kits included two International brand 1 mA meters.   They had 100 
ohm movements, as delivered.  Somehow, Tom had found that  there was an 
internal series resistor in these particular movements.   Jumpering (shorting) the 
resistor brought the series resistance of the meter  down to about 38 ohms (on 
the one I got from him).  That was close enough  to the 18 ohm spec that the 
meter actually worked in the application.  I  had occasion later to compare 
the meter movement to a couple of correct  original meters.  On the same radio, 
same signal source, could see no  difference in the meter readings.  
 
Tom supplied a some standoffs and diodes for the line level conversion, all  
of the hardware, a special socket to disassemble the meter face, and sets of  
both white face and black face meter scale overlay stickers.  A nice kit,  
however I believe he has been out of them for years now.
 
I still have his instructions and will scan and send them, if anyone is  
interested.  (It may be next week before I can respond however.)
 
Two caveats, 1) If you find a kit, these are the glow in the dark  movements, 
so open the cases at your own risk.  And 2) If you are looking  to convert 
other International brand 1 mA meters, I have opened many of them and  have 
never found another with this internal construction (with series  resistor to short
).  Tom found an interesting stash!
 
73
Harry  KG5LO
Saline MI  48176