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The amplifier tank coil has been removed in this view to obtain an unobstructed viev of the components on the rear wall of the box. RFC2 is mounted on a small cone insulator at the upper right. The two resistors immediately below the choke are R4 to the left and R3 against the rear wall. The two mica capacitors near the coil socket are C6 below and C4 above. Suspended from the top wall of the box is the microphone transformer. The mounting tabs may have to be trimmed with tin shears, so that the transformer will fit inside the box.

Power Supply and Adjustment

    For an input of 10 watts to the final , a power supply delivering 260 volts at 100 ma, will supply both r.f. and audio sections. The most-common types of vibrator supplies will meet these requirements. The power unit of the ordinary car radio will furnish enough power for an input of about 4 watts to the final. If the car radio has a push-pull output stage, its supply ought to have enough output to runn the final at almost the full 10-watt input. In either event, the receiver


power units will not handle both receiver and transmitter simultaneousely.
    So far as the adjusment of the transmitter is concerned, there is only one control -- the one resonating the amplifier tank for plate-current dip. Adjustment of the antenna is discussed in the ARRL Handbook. The coupling should be adjust so that the final draws about 40 ma. A high-resistance voltmeters with an r.f. choke in its negative lead shoukd read 60 volts or more across the 22 K amplifier grid leak.

Rear view shpwing the mounting of the components at the rear of the box. The tube above the modulation transformer the 6AQ5 modulator. Below are the AQ5 r.f. amplifier to the left, and the 6C4 oscillator to the right, This viev also shows the stud for fastening the unit to the Instrument panel.
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