HP Q METER 4342A User Manual

Section III
Model 4342A
Parallel Connection Measurements
g.
h.
1.
j.
k.
1.
3-22
Depress AQ button and adjust AQ ZERO
(COARSE and FINE) controls so that
meter pointer indicates zero (full
scale) on AQ scale.
Note
Press AQ button to release AQ func-
tion and recheck for current reso-
nance. Again depress the AQ button
and recheck for AQ zero indication.
Place the sample material between
1645lA electrodes. The sample mate-
rial should be in close contact with
electrodes. Note 164SlA micrometer
reading TX (as thickness of the
sample).
Again adjust the L/C and AC dial con-
trols for resonance. Note sum of the
C dial and AC dial readings as C3 and
panel meter AQ reading.
If meter
pointer scales out at the left end of
the scale (AQ full scale), reset the
function for normal Q measurement.
The difference in Q is calculated
from the two Q values as AQ = Q2 - 93.
Remove the sample material from be-
tween the 1645lA electrodes.
Let the L/C and AC dial settings remain
as is, and reduce space between the
1645lA electrodes until resonance
again occurs. Note the micrometer
reading as To.
Note
If this procedure is a little diffi-
cult,
let the distance between the
16451A electrodes remain the same as
the thickness of the sample being
measured and take resonance again
by adjusting the L/C and AC dial
controls.
Note sum of the C and
AC dial readings as CI,.
Calculation formulas of the dielectric
constant, dielectric loss, and asso-
ciated measurement parameter values
are summarized below:
Specific inductive capacity of the
sample material is:
Es =
TX
To . . . . . . . . . . . . . . . . (eq. 3-29)
Dielectric constant of the sample
material is:
E = EO’ES
TX
= - x 8.85 x lo-" (F/m)
To
. . . . . . . . . . . . . . . (eq. 3-30)
Electrode capacitance with the sample
material is:
cx = +
(PF)
= c4 - c3 + &
(PF) . .
(eq. 3-31)
Where,
the unit for TX and To is cm.
Equivalent parallel conductance of the
sample material is:
Gx = 2TrfC1
Qz (Qz- AQ)
..(eq. 3-32)
Dielectric loss angle (dissipation
factor) of the sample material is:
tand = Cl . To
AQ
Q2(Q2 - AQ>
Cl
AQ
= ??c ' Q2(Q2 - AQ)
= Gx/2nfCx . . . . . . . . . . . (eq. 3-33)
Where, f is measurement frequency.
Note
%2?
may be used instead of
AQ
Q2(Q2 - AQ)
in equation 3-33.
Q value of the sample material is:
Qx = l/tan B . . . . . . . . . . . . . . (eq. 3-34)
Note
The theoretical formula for 1645lA
electrode capacitance is:
c =
s x1o-2
(F) = '
(PF)
36.~1 xlOg xTo 3.6~ To
where S is area of electrode (cm2).
Since the size of the electrode is
3.8cm in diameter, C aboke can be
shown to be l/To (pF).

HP Q METER 4342A Specifications

General

Brand	HP
Model	Q METER 4342A
Category	Measuring Instruments
Language	English