[R-390] Sticking Carrier Meter

[Charles P. Steinmetz]

Ken wrote:

>I'll get onto it this weekend and let everyone know how it went...

One thing before you dive in:  I believe you mentioned loosening the 
movement screw as a potential fix.  If anything, the meter bearings 
should have more clearance now than they did when the meter was new, 
due to wear.  So it is probably not advisable to loosen the bearing 
screw, unless you can clearly see that some physical damage has moved 
one bearing closer to the other (almost certainly not the case).  The 
cause of the sticking is much more likely to be (i) crap in the 
magnet assembly rubbing on the armature, (ii) something else rubbing 
(needle on face, spring on wire, etc.), or (iii) dirt/grime in the 
bearings.  Loosening the bearings won't help the first two, and even 
if it helps the third, it is the wrong thing to do and the "fix" 
won't last long.  Figure out what is the matter, and fix that.  If 
it's dirty bearings, use a *non-magnetic* small pointy thing (e.g., 
plastic toothpick) to put solvent in each bearing, then exercise the 
meter, then put in more solvent, etc., etc.  When it is free, use the 
pointy thing to put the smallest drop of very light oil on each 
bearing.  (Light mineral oil like sewing machine oil or the oil that 
comes with electric shavers is good.  Real watch oil is, too.  Sperm 
oil, if you have any (which is probably what it had from the 
factory).  Jojoba oil works fine if you can't find any of the 
others.  Do NOT use 3-in-1 oil or similar oxidizing oils.

General axiom of troubleshooting and repair, # 17:  Don't fix the wrong thing.

Best regards,

Charles