Project ------ Frequency meter LCD 30 MHz ------ Freq. 70 MHz ------ Freq. 70 MHz II |
Project that uses a PIC 16F84A and can be made in two versions. Using the HP 2414 display (photo on the left) which is difficult to find but, as you can see, the creation becomes extremely compact. The photo in the center shows the version with the 8x1 LCD. The version with the HP display measures up to 70 MHz, in the photo it is measuring 75.1 MHz. Photo on the right shows the internal layout of the components: the 7805 integrated circuit has undergone surgery (space reasons..). The input circuit serves to increase the reading sensitivity. Using the LCD display instead of the HP, the connections must be modified as follows compared to the electrical diagram: LCD pin 1 GND Files to download for program. the PIC: Meter.zip |
 Another version always with the PIC 16F84. Characteristics : 8 digit display, maximum frequency 50 MHz with 5 Hz resolution, button h = hold freezes the reading, r = reset obviously resets the reading. |
