SCI - 10
                 Copyright (C) 1992 Homer Wilson Smith
       Redistribution rights granted for non commercial purposes.
 >     One of them (Electra I think -- I haven't saved the posts) went
 >as far as stating that all meters built according to a design that had
 >been finalized after Ron lost control of the Church was faulty.  Her
 >words was something like "If I come across a Mark  I
 >destroy it -- and consider it my good deed for the day".
     This is unfair of Electra.
     The Mark VI is a beautiful meter and well worth owning.
     The Mark VI has gotten somewhat of a bad name in the field for a
number of reasons.
     1.) The new field meters are made very differently being
specifically designed to not have any 'swing' in the meter mechanism.
This kind of caught on as a vogue sort of thing, some people swear by
it, and it was convenient to put down the Church's latest 'Mark' for its
standard loose movement.
     As you know of any meter when the needle swings over to an area
either because of electrical signal or because of human adjustment, it
over shoots and then comes back and undershoots, going into an
oscillation around the resting point that eventually dampens out.  This
damping factor is provided by the very nature of the meter core and coil
mechanism itself and by electrical circuitry to help the damping.
     The field meters were made with a much heavier needle movement, the
meter mechanism itself is somewhere around 500 microamps full swing,
rather than the 100 microamps of the standard meter.  Thus the field
meters were like totally damped, they almost looked broken as the needle
would just go to where it was going and stop like it ran into crazy
glue.  This totally threw people who were used to the normal behavior of
the Mark V and VI, and once they got used to it, they could never go
back.  Thus the Mark VI became sort of a laughing stock.
     2.)  The Mark V meter has a one piece self damping magnetic core
around the coil of the meter so it has a natural but loose feel.  The
Mark VI has a split core around the coil so its damping is severely
missing.  Thus a small short circuit was introduced across the meter
with a variable resistor that allowed for fine tuning the damping of the
      It also allowed technicians to incorrectly damp the needle so that
it was too damped or not damped enough.  Some have charged that some
Mark VI's may have been factory tuned to be over damped, so it may be
that some of the Mark VI's that you run into are definitely tighter than
the Mark V, but not seriously so.  In any case a quick sortie into the
case can adjust the damping to any level you might enjoy.
your Mark VI with a Mark V if you have any doubts as to the competency
of the setting.
     It has been suggested that the damping or some other part of the
meter was intentionally mistuned to make NOTS reading harder, to extend
the time on NOTS so that people would have to pay more money or be on
course endlessly.
     If I ever find out any information that someone has been doing this
I will personally scream bloody murder even if it is the Church that is
the guilty party.  If you have information on this which you do not feel
comfortable dealing with yourself, please e-mail me anonymously with the
data.  I am a safe terminal.  (Said the Fox).
     Otherwise if you are suspicious that anyone in the Church is or has
done this, please write it up immediately.  If you get the cold shoulder
or no answer, write THAT up.
     3.)  The Mark VI has a linear taper sensitivity knob, whereas the
Mark V has a reverse log taper.  This is because the reverse log taper
pot with the on/off switch was popular during the war time of the 50's
and 60's.  Then people stopped making them.  Eventually they became too
hard to find, and the linear taper became the standard.  You will notice
the sens knob and the on/off switch on the Mark VI are two different
controls now.  Mark V's are also hard to service when the sens knob goes
bad, because there just ain't alot to be found.
     Both meters however have 1 to 32 on their sensitivity knob and both
meters are equally sensitive at the 1 setting and at the 32 setting.
     This is easy to check out.  Set your TA to 2.0 and your sens to 1.0
and adjust your meter trim knob so that the needle does not move at all
when you turn the sensitivity up to 32.  This means the needle is at the
set point which may or may not be at the set mark on the dial.  It
probably won't be but should not be very far away from it.
     The set point is the balance point of the meter.  If something
drives the needle to the right of the set point and you turn up the
sensitivity it will move further to the right.  If something drives the
needle to the left of the set point and you turn up the sensitivity it
will move further to the left.  By setting an internal adjustment the
set point can be brought to coincide exactly with the set mark on the
dial.  However it is unlikely to stay there over time, so don't be
concerned if your set point is a few small divisions away from the set
     Once you have gotten the needle exactly on the set point, which
means that turning up the sens knob does not move the needle at all,
then turn the sensitivity back to 1, and move the needle using the Tone
Arm until the needle is 2 small divisions to the right of the set point.
Then turn the sensitivity up to 32.  The needle will move further away
from the set point almost all the way across the dial as the 2 division
movement is magnified by the increasing sensitivity.  Do this experiment
with both a Mark V and Mark VI and you will see they both magnify the
same amount from 1 to 32.
     However for settings inbetween the two settings of 1 and 32 the
sensitivity of the Mark VI is very different than the Mark V.  The Mark
VI has to be turned up MUCH higher towards 32 to get the same
sensitivity as the Mark V.  In fact most of the increase in sensitivity
on the Mark VI takes place between 30 and 32!
     Thus if you are used to running your Mark V at a sensitivity of 4
to 6, you will need to run your Mark VI at a sensitivity of 30!
     It is probably this that has lead many detractors of the Mark VI to
say that it was made unsensitive so that it could not read NOTS
material, or pick up R/S's (Rock Slams).  If this is true, then it must
have been a really dumb Auditor to fall for it.
     Much of the technical material on metering was written when the
Mark V was the instrument of choice, and people may have gotten used to
the fact that most pcs ran between 4 and 6 on the sens dial.  If they
then start using the Mark VI, they will find the needle dead and
unresponsive if they insist on continuing to run at 4 to 6 on the sens
setting.  And yes they will miss read on their pcs.
     However there are standard proceedures for setting the needle on
any meter that is independent of the specific numbering system on the
sensitivity dial.  If you follow these as instructed you will have your
Mark VI set properly just as you will a Mark V.  However your Mark VI
sens setting will be considerably higher than the Mark V.
     This applies only to those meters that have this difference in the
sens control.  It may not apply to all Mark VI's.
     Electra I hope you are reading this.  You have anything to say for
Homer Wilson Smith (Holmes)     Support anonymous mail servers