Iy

The unknown parallel inductance, Lx, and storage factor, Qx, can easily be found to be:

10ti

3. Measurement of matched 72-ohm coaxial line at 830 kc.

Set the 4-position switch at 1 Mc and the coil switch on the 620-850 kc range. Establish an initial balance with the conductance condenser set at zero and the susceptance condenser at some value near mid-scale. Connect the impedance to be measured to the UNKNOWN terminals with a small "postage-stamp" type fixed condenser in series with the ungrounded lead. Change ibis series condenser to find the largest value for which a balance on the conductance dial can be obtained. Say this is 150 jujuf, nominal value.

Leave the ground terminal of the unknown impedance connected to the grounded UNKNOWN terminal. With the fixed condenser connected to the ungrounded UNKNOWN terminal, but free at llie far end, establish an initial balance with the conductance condenser set at zero and the susceptance condenser at some relatively high value, say 500 /J./J.L

Connect the free end of the series condenser, c„ to the grounded UNKNOWN terminal and rebalance. If there is any appreciable change in conductance balance, rebalance with the zero-adjustment trimmers across the conductance condenser. leaving the conductance dial set at zero. Let the susceptance condenser reading be 352.5 ¡j-jui. Then:

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