Dip meters measure an antenna's resonance.
A dip meter is an oscillating device that can be used for a variety of tests on a radio and radio antenna. This piece of radio testing equipment is not a precision device but can replace several pieces of laboratory equipment. Amateur Ham operators use the dip meter so they do not have to go to the expense of purchasing the more elaborate testing devices required to maintain and troubleshoot their broadcast equipment. You must know a lot about electronics to build a homemade dip meter, but it is worth the time if you can build one.
Instructions
1. Set the detector circuit board on a flat surface. Install three of the diodes on the circuit board and solder in place, as per the electronics circuit diagram. Each diode connection will be color coded on the circuit board and diagram. Cut off any excess lead lengths once you have soldered the leads of the diodes onto the circuit board.
2. Insert five of the resistors onto their connection points on the detector circuit board and solder in place. Cut off any excess lead wires after you have soldered them in place. Insert one more resistor on the detector circuit board, but in a vertical position, on the corner of the five previously installed resistors. Solder the vertical resistor in place. Match each resistor position with the electronic circuit diagram and color codes.
3. Snip the insulation off the end of each leg of five capacitors so the insulation is even with the circular body. Solder one capacitor next to each resistor. Cut off any excess lead wires after solder, and push the capacitor over toward the closest resistor. Solder one transistor onto the detector circuit board.
4. Push the push-button switch onto the precut holes on the detector circuit board. Solder the switch's lugs to the circuit board. Mount the tuning capacity to the other end of the detector circuit board. Insert screws through the bottom of the circuit board and into the bottom of the tuning capacitor. Make sure you install washers between the circuit board and the bottom of the tuning capacitor.
5. Set the oscillating circuit board on a flat surface. Wrap the leads of a capacitor around the leads of a resistor. Solder the leads together. Make two more resistor capacitors similar to the first one. Install the resistor capacitors onto the oscillating circuit board and secure in place with solder. Solder three more resistors onto the circuit board just like you installed them on the detector circuit board. Solder a transistor to the oscillating circuit board and two more capacitors. Remove the blue insulated telephone wire and strip the ends, leaving bare wire. Solder one end of the blue wire to the foil on the oscillating circuit board. Leave the other end free.
6. Solder the other telephone wires to the detector and oscillating circuit board as described in the dip meter wiring diagram. Solder the four pieces of sheet metal together making a small electronic chassis or box with open ends. Mount the phone jack onto the chassis by drilling small holes and screwing the jack in place. Connect each end of the telephone wire to the telephone jack wire connections as per the color coding on the jack's wire mounts.
7. Solder more telephone wire to each spot on the detector and oscillating circuit board where the first wires are connected. Run one wire to each of the other electrical components, such as the coil, battery connector and round dial knobs. Test each connection with the circuit tester to make sure you have no breaks in the circuits.
8. Set the entire electronic assembly inside the metal box. Mark the positions of each mounting holes and the placement of the push-button switch. Remove the electronics assembly and drill holes where you have marked it. Mount the electronics assembly in the metal box. Place the foam under each circuit board and electronic component between the components and the metal box. Make sure you push the switch through its hole so you can turn the dip meter on from the outside of the box.
9. Install the 9-volt battery into the battery connector. Calibrate the dip meter to a known frequency. Make any adjustments as necessary and start using your homemade dip meter.
Tags: circuit board, detector circuit, detector circuit board, oscillating circuit, oscillating circuit board, excess lead
