Figure 2 Alternate Test circuit for I F transformer. There is a block on the left which is labeled SDG810 function generator. A symbol on the right edge of this block indicates that it has a coaxial output. The center of the coax goes to one end of a resistor that can be either 100 k ohm or 470 k ohm. The shield of the coax is grounded. The other end of the resistor connects to the top of the primary of the I F transformer that is under test. The bottom of the primary is grounded. The I F transformer consists of two windings which are magnetically coupled but do not have an iron core. Each winding has a variable capacitor connected in parallel with it. Both windings and both capacitors are surrounded by a dashed line indicating a shield. The shield is grounded. The bottom end of the secondary is grounded. The top end connects to channel 1 of an oscilloscope. The ground of the scope is grounded. Channel 2 of the scope connects to the junction of the resistor and the top of the primary of the transformer. Above the function generator block is another block which is labeled any cheapy function gen. Its output connects to the trigger input of the SDG810. Although not indicated, this connection includes grounding. The output of the cheapy also connects to the external trigger input of the oscilloscope. This completes the verbal description.
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