Figure 4 Ohmmeter Circuit of RCA WV77. As described previously the common jack connects directly to circuit common and through a parallel RC circuit to chassis. The AC OHMS jack connects to the rotor of S2E. The jack also connects to the ohms stator of S2F. The rotor of S2F connects to the 3.3 meg ohm resistor that leads into the measuring circuit. The ohms stator of S2E connects to the rotor of S1C. This switch wafer selects the resistance range resistors. The RX1, read as R times one, stator connects to one end of an 8.2 ohm resistor. The r times ten stator connects to one end of a one hundred ohm resistor. The r times one hundred stator connects to one end of a 1.0 k ohm resistor. The r times 1 thousand stator connects to one end of a 10 k ohm resistor. The r times 10 thousand stator connects to one end of a one hundred k ohm resistor. The r times one hundred thousand stator connects to one end of a 1.0 meg ohm resistor. The r times one million stator connects to one end of a 10 meg ohm resistor. The other ends of all 7 of the above resistors are connected together and go to one end of a one half amp fuse. The other end of the fuse goes to the positive terminal of a 1.5 volt cell. The negative end of the cell goes to circuit common. A reminder. This circuit gets connected to the measuring circuit through S2F described near the beginning. This completes the verbal description.
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