Building the Receiver

The receiver board is placed in a box with enough room left over to mount the external components. A box can be purchased, or one can be made by soldering pieces of printed circuit board together. At the very least, only the bottom, front, and rear sides are needed.

The tuning capacitor and volume control are mounted on the front of the box that the receiver board is placed. The most critical is the tuning capacitor. The leads to the capacitor should be as short as possible. Use heavy wire to prevent frequency changes due to vibration or movement of the receiver box.

The recommended location for the tuning capacitor is near the middle of the board close to its connection on the board. The volume control can be placed to the left of the tuning capacitor.

Two components are mounted on the back of the receiver box. One is for providing power and the other is the antenna connector. Two binding posts or a RCA phono jack is mounted on the back of the box to provide a place to connect the output from a 12 volt DC (Direct Current) power supply. If you plan to use a wall plug-in power supply, check the power plug supplied and use the correct jack. For an antenna connector, use a binding post, RCA phono jack or a coax connector.

The speaker can be mounted internally with the receiver or a phono jack can be used to connect an external speaker. The connector for an external speaker is usually placed on the rear of the box. An internal speaker is usually mounted on the front or top of the box.

Mount the board inside the box with 1/2" to 1" metal spacers and screws. All the wires that need to go off the board are marked with an arrow for easy identification. These locations are the ANT (antenna), SPEAKER, 12 VOLTS, VAR RES (volume control), and the tuning capacitor (WIDE or VAR CAP). For best results, run a ground wire with all these components. Use the most convenient ground with your layout.

Hook up all the off-board components. The volume control (VAR RES) has three leads. One of the outside leads goes to 5 volts, the other outside one goes to ground, and the middle one goes to the "VAR RES" pad on the board. If it works backwards, just reverse the outside leads. The speaker has two leads - one goes to "SPEAKER" and the other to "SPEAKER GROUND".

The stator (the plates that do not move) of the variable capacitor goes to the pad on the board marked "VAR CAP" or "WIDE". "WIDE" is the recommended location for initial use and for experimenting. The rotor (the plates that move) connects to the closest ground on the board.

The "ANT" on the board goes to the antenna connector. The antenna connector can be a coax connector, RCA phono jack, or a binding post.

Hook up the positive lead of the power connector to the "12 VOLTS" pad on the board. The ground of the power connector should go to the closest ground on the board. Be sure to apply "+" to the "12 VOLTS" pad on the board and the "-" to ground.