2A

The microphone is cemented to the case, Ihe hole m the back cover should linę up with the bushmg.

Mount all parts on board before enclosing in case Use epoxy cement on inside edge to keep in place

space the control approximately ¹ W' nway from the printed circuit board. Cut off the smali pointer projection on the control knob so that the knoh clears the opening in the case. The knob can be painted with a contrasting color.

Attach a ground lead from point D on the circuit board to the ground lug under the threadcd spacer. Capacitor CS is con-nccted betwcen J2 and point B. Another lead connects J1 to point A. If the leads are strong enough, they can be relied upon to keep the board in plnce; other-wise. the board can be cemented in place with a drop of epoxy cement on each end of the board.

Cheek all wiring and be surę to ob-serve battery polarity. An RCA type phono pług is used to hołd the antenna. If you have difticulty getting a case or any of the parts for this project, try Deinco. Box 16041, San Antonio. Texas 78216. t Sce Parts List.)

Finał Adjustment. Turn on your FM radio and tune it to a elear spot on the dial, near the center of the band. Use a nonmetallic tuning tool and rotate the core of LI until quieting or a feedback howl oceurs. It should be possiblc to ad-just the wireless microphone to work almost anywhere on the FM band. The exact tuning rangę depends upon the type of antenna used and component tolerances.

Adjust the volume control and the re-ceiver volume so that no feedback howl oecurs. The amount of volume you can use will depend upon your distancc from the loudspeaker, and room acoustics. The FM Wireless Microphone can be carried in your shirt pocket, or placcd in a suit-able location to pick up the desired sounds. If you use a lavalier type of microphone, all or part of the neek cord can be replnced with a piece of insulated wire. one end of which is plugged into the antenna Jack to servc as an antenna, thus inereasing the rangę.

The antenna should not be allowed to move around too frecly, beeause body capacity can cauae a ehange in the fre-queney of operation. If this is a problem, replace capacitor CS with a 1-pf. capacitor. If you cannot get the microphone to work. cheek the transistor voltagcs they should be within 20%.    -30-

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