Article
Multifunction Frequency Meter
For all time-related measurements
Despite its surprisingly simple hardware design and construction, the superb frequency meter / event counter described in this article couples ease of use to a plethora of measurement options. The successful combination is mainly due to the use of a microcontroller running some really ingenious software. The keywords in the general design of the instrument were noise immunity, reliability and functionality.A frequency meter / event counter is an indispensable instrument on the electronics laboratory workbench. In general, the basic circuit of the instrument is not particularly complex. Digital integrated circuits have been available for quite some time that are capable of performing frequency and time measurements, as well as pulse counting. The same ICs also cheerfully handle the job of displaying measurement results on an LC or LED display. These days, counters are just ‘add-ons’ to function generators and get the matching amount of attention!
Materials
Gerber file
CAM/CAD data for the PCB referred to in this article is available as a Gerber file. Elektor GREEN and GOLD members can exclusively download these files for free as part of their membership. Gerber files allow a PCB to be produced on an appropriate device available locally, or through an online PCB manufacturing service.
Elektor recommends the Elektor PCB Service service from its business partner Eurocircuits or AISLER as the best services for its own prototypes and volume production.
The use of our Gerber files is provided under a modified Creative Commons license. Creative Commons offers authors, scientists, educators and other creatives the freedom to handle their copyright in a more free way without losing their ownership.
PCB
Component list
Resistors:
R1,R23 = 33kOhm
R2,R10,R13 = 1kOhm 8
R3,R12,R15,R40-R47 = 150Ohm
R4-R8 = 1kOhm 5
R9,R17 = 100kOhm
R11,R18 = 68kOhm
R14,R30-R37 = 3kOhm 3
R16 = 22Ohm Ohm
R19,R21 = 8kOhm 2
R20 = 10kOhm
R22 = 1MOhm
P1 = 10 kOhm preset H (with spindle, see text)
Capacitors:
C1 = 10µ F 25V radial (optionally tantalum)
C3 = 10µ F 16V radial (optionally tantalum)
C2,C4,C5,C6 = 100nF
C7-C10 = .47µ F 16V radial optionally tantalum)
C11,C12 = 22pF
C13,C14 = 10µ F 16V radial optionally tantalum) (only if required)
Semiconductors:
D1 = 1N4001
D2,D3 = zener diode 5V6, 500 mW
D4 = zener diode 4V7, 500 mW
D5,D6 = BAT46
T1-T8 = BC327-25
IC1 = AT90S2313-10PC, programmed, order code 030136-41
IC2 = 74HCT42 or 74HC42
IC3 = LM393 (8-pi DIP)
IC4 = 7805
Miscellaneous:
JP1 = 3-way jumper
JP2-JP5 = 2-way jumper
K1 = 2-way PCB terminal bock, lead pitch 5mm
K2,K2A = 14-way SIL pinheader
S1 = pushbutton, 1 make contact (small model)
S2 = BCD switch (16 positions)
X1 = 10MHz quartz crystal
LD1-8 = SA52-11SRWA (Kingbright)
IC sockets: 6-way, 8-way, 16-way, 20-way
Heatsink for IC4 (U25, 30K/W)
PCB, order code 030136-1
Disk, project software, order code 030136-11 or Free Download
R1,R23 = 33kOhm
R2,R10,R13 = 1kOhm 8
R3,R12,R15,R40-R47 = 150Ohm
R4-R8 = 1kOhm 5
R9,R17 = 100kOhm
R11,R18 = 68kOhm
R14,R30-R37 = 3kOhm 3
R16 = 22Ohm Ohm
R19,R21 = 8kOhm 2
R20 = 10kOhm
R22 = 1MOhm
P1 = 10 kOhm preset H (with spindle, see text)
Capacitors:
C1 = 10µ F 25V radial (optionally tantalum)
C3 = 10µ F 16V radial (optionally tantalum)
C2,C4,C5,C6 = 100nF
C7-C10 = .47µ F 16V radial optionally tantalum)
C11,C12 = 22pF
C13,C14 = 10µ F 16V radial optionally tantalum) (only if required)
Semiconductors:
D1 = 1N4001
D2,D3 = zener diode 5V6, 500 mW
D4 = zener diode 4V7, 500 mW
D5,D6 = BAT46
T1-T8 = BC327-25
IC1 = AT90S2313-10PC, programmed, order code 030136-41
IC2 = 74HCT42 or 74HC42
IC3 = LM393 (8-pi DIP)
IC4 = 7805
Miscellaneous:
JP1 = 3-way jumper
JP2-JP5 = 2-way jumper
K1 = 2-way PCB terminal bock, lead pitch 5mm
K2,K2A = 14-way SIL pinheader
S1 = pushbutton, 1 make contact (small model)
S2 = BCD switch (16 positions)
X1 = 10MHz quartz crystal
LD1-8 = SA52-11SRWA (Kingbright)
IC sockets: 6-way, 8-way, 16-way, 20-way
Heatsink for IC4 (U25, 30K/W)
PCB, order code 030136-1
Disk, project software, order code 030136-11 or Free Download
Discussion (0 comments)