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following symbols are used in the fee schedules for materials urements:

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H/10 = μ μ* = μ'-jμ" = '(1-jtan 8m),

e the permeability of free space in MKS units is μ = 4π X 10-7 y/meter, and from Hoo = c2, c = speed of light, &= 8.8542 x 10-12 d/meter. The conductivity σ is expressed in mho/meter. The magnetization expressed in gauss (mixed Gaussian units). The saturated value is omarily multiplied by 4π and denoted by 4πM, The magnetic field H is ersted, Oe, and the gyromagnetic ratio g is in MHz/Oe.

102 Preparation of Specimens

s

er preparation of specimen sizes, tolerances, and surface finish is an rtant prerequisite to the accurate measurement of electromagnetic properties. Fee List assumes that the samples are suitably dimensioned, shaped, and shed. Depending on the workload, shop facilities at NBS Boulder provide cutting, surface grinding, and turning of materials. These services include ge grinding or turning of small rods, and the forming and polishing of res. The cost of this service is in the range of $10 to $12 per hour 8 wage scale).

103 Fees

Fee List for electromagnetic properties measurements contains two costs. larger amount is the cost of measuring one specimen or the first of a of similar specimens. The smaller amount, in parentheses, is the cost specimen for measuring additional similar items of the set. To change ther frequencies with one instrument, such as a Q-meter or bridge, may be treated as an additional item and may be done at the lower cost. The of changing instruments - for example, from a Q-meter to a slotted line over a wider frequency range will be $50 to $75. Millimeter wave liquid urements at a series of temperatures may be done at the lower fee cost. ee Schedules 251.261 and 251.262 the main price is for an initial room erature measurement plus one high temperature point. The price in parentheses or each additional high temperature point. Low temperature measurements be at the higher cost.

urements under special conditions, of extreme values, to serve in referee s, etc., where extra work is required may be at extra cost.

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RODS AND CYLINDERS, SMALL COAXIAL TUBING, AND LIQUIDS

Service available:

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(1)

(2)

(3)

(4)

Capacitive 2-terminal dielectric holder (Hartshorn method) with
1- to 2-inch diameter circular electrode plates, observed by
suitable bridges. The specimen is a flat disk, usually smaller
in diameter than the electrodes. In case a very low intrinsic loss
is obscured by surface conductivity from adsorbed water vapor
(Section 251.100), the disk may be larger than the electrodes.
Capacitive holder and sample of method (1) observed by means of
Q meters.

Toroidal dielectric specimen link-coupled to a pancake coil; see
R. C. Powell and A. L. Rasmussen, A radio-frequency permittimeter,
IRE Trans. Instr., Vol. I-9, Sept. 1960, 179-184.

TMOMO

mode circular cavity resonator at 0.5 GHz and 1.1 GHz using a right cylindrical rod 2.25 inches in length, for low loss materials; see A. J. Estin and H. E. Bussey, Errors in dielectric measurements due to a sample insertion hole in a cavity, IRE Trans. on Microwave Theory Tech., Vol. MTT-8, Nov. 1960, 650-653.

(Continued on following page.)

conductor; a disk specimen is used.

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It is necessary that the rod

Circular cylindrical rod or disk specimen in a circular TE mode resonator, or a liquid in a hollow tube. 011 be non-elliptical.

Slotted-line measurement in coaxial and in rectangular waveguide. Measurements of tubular dielectrics (spaghetti) using method (6). } Liquid measurements by an interferometer; may be performed at a series of temperatures.

See Part 1, Section 200.103 (b) and (d), also Section 200.109 (d). Larger limits of uncertainty may occur in difficult cases, for example when ' and/or e" are greater than 100, and when the geometry is far from ideal.

1

The limits of uncertainty for tan & = "/ε' are usually ± 0.00005 or ± 5%, whichever is the larger. See remarks in Section 251.100 on the loss tangent contribution of a foreign surface conductivity.

Limits of uncertainty for loss tangent by methods (7,8) may increase to± 0.0002 or ± 5%, whichever is the larger.

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RODS AND CYLINDERS, SMALL COAXIAL TUBING, AND LIQUIDS

Service available:

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(1)

Capacitive 2-terminal dielectric holder (Hartshorn method) with 1- to 2-inch diameter circular electrode plates, observed by suitable bridges. The specimen is a flat disk, usually smaller in diameter than the electrodes. In case a very low intrinsic loss. is obscured by surface conductivity from adsorbed water vapor (Section 251.100), the disk may be larger than the electrodes. (2) Capacitive holder and sample of method (1) observed by means of Q meters.

(3)

(4)

Toroidal dielectric specimen link-coupled to a pancake coil; see
R. C. Powell and A. L. Rasmussen, A radio-frequency permittimeter,
IRE Trans. Instr., Vol. I-9, Sept. 1960, 179-184.

TMOMO

Om0.

mode circular cavity resonator at 0.5 GHz and 1.1 GHz using a right cylindrical rod 2.25 inches in length, for low loss materials; see A. J. Estin and H. E. Bussey, Errors in dielectric measurements due to a sample insertion hole in a cavity, IRE Trans. on Microwave Theory Tech., Vol. MTT-8, Nov. 1960, 650-653.

(Continued on following page.)

conductor; a disk specimen is used.

Circular cylindrical rod or disk specimen in a circular TE mode

resonator, or a liquid in a hollow tube. It is necessary that the rod

be non-elliptical.

Slotted-line measurement in coaxial and in rectangular waveguide.
Measurements of tubular dielectrics (spaghetti) using method (6).
Liquid measurements by an interferometer; may be performed at a
series of temperatures.

See Part 1, Section 200.103 (b) and (d), also Section 200.109 (d). Larger limits of uncertainty may occur in difficult cases, for example when ' and/or e" are greater than 100, and when the geometry is far from ideal.

The limits of uncertainty for tan & = "/ε' are usually ± 0.00005 or ± 5%, whichever is the larger. See remarks in Section 251.100 on the loss tangent contribution of a foreign surface conductivity.

Limits of uncertainty for loss tangent by methods (7,8) may increase to ± 0.0002 or ± 5%, whichever is the larger.

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