IT-28 question

[Fredric Newman]

Hello to all who own the IT-28 capacitor tester or know it well,
        I just bought one and while recalibrating it I have come across a
possible deviation from the norm.  Found on page 24 of the manual, under
Testing, following is the procedure I am referring to:

Set the controls to the following positions.

CONTROL                                                 POSITION
BRIDGE-LEAKAGE                                  BRIDGE

GEN.                                                            INT.

TYPE SWITCH                                             Any

VOLTAGE                                                 3

POWER FACTOR                                    0

RANGE*

*For positions R X1 through C X1, the eye tube should be closed with the
Balance control in any position except maximum clockwise.  The tube should be
open when the Balance control is maximum clockwise.  Position the Balance
control maximum clockwise and with your finger touch the negative TEST
terminal.  The eye tube should tend to close when the RANGE switch is in
positions R X100 through C X.01.

The pointer on my BALANCE control rests when in the clockwise position where
the horizontal line that is labeled Capacitance "C" meets the downward
vertical line.  I recorded the following during this test:

RANGE switch position RX1               eye closes when RANGE pointer is
turned
counterclockwise to rest where horizontal line
                                labeled Resistance "R" line meets the
downward
vertical line

RANGE switch position RX100     same as RX1

RANGE switch position RX10K     eye closes when RANGE pointer is turned

counterclockwise to .1 on Capacitance "C" scale

RANGE switch position CX.0001   eye closes when RANGE pointer is turned

counterclockwise to .7 on Capacitance "C" scale

RANGE switch position CX.01     Same as RX100 and RX1

RANGE switch position CX1               Same as RX100 and RX1

In addition, during the above "finger touch" test, I found that while in the
RX10 and CX.0001 postions the eye closes completely when touching the
negative test terminal.  The eye does not close as much in the RX100 position
and even less in the CX.01 position.

If anyone can run the above tests and let me know the result compared to my
results, I would be very gratefull.  Perhaps there is a tolerance that my
unit is within.  I can't know this without other unit's relative readings.

Please reply direct to spare other members the use of the "delete" key.
Thank you in advance.  Fred/WA8IDI /6

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