En Frekvenstæller skal man også bruge ellers er man lorst hvis man vil bygge selv, jeg har købt der her.
Section one: General description
I Introduction
This instrument is one of multifunctional and hi-precision frequency conters that measures frequency from 10Hz to 2700MHz
It features eight digits, bright seven segment LED display, four function performance. Low power consumption circuit design, small size,light weitht,high-stabilized crystal over oscillator for measurement of accuracy and full input signal conditioning
The four functions are frequency, period,totalize and selt check.
This is acconplished by a single chip microcontroller,The input signal can ge conditioned by attenuation, It is recommended that whole information and details should be read and understood before attempting to operate the instrument for correct operation and best results.
II Specification
The pertinent specifications are listed as follows:
Frequency measurements.
Channel A
Range: 10Hz~10MHz direct counter.
10MHz to 100MHz prescaled by proportion.
Resolution: Direct counter: 1Hz?10Hz?100Hz switch selectable.
Presscaled: 10Hz?100Hz?1000Hz switch selectable.
Gate time: 0.01s , 0.1s , 1s switch selectable.
Accuracy: ±1 count±timebase error×measured
Channel B
Range: 100MHz~2.7GHz
Resolution: 100Hz?1kHz?10kHz
Gate time: 0.01s ?0.1s?1s
Accuracy: ±1 count ± time base error × measured frequency
Period measurements
Input: Channel A
Range: 10Hz~10MHz
Rslolution: 10-7s?10-8s?10-9s switch selectable
Accuracy: ±1count±timebase error measured period
Totalize measurements
Input : Channel A
Range: 10Hz~10MHz
Resolution: ±1 count of input
Check: 8 bits repeating display 0~9 together
Input characteristics
Channel A
Input sensitivity
10MHz range: 10Hz~8MHz 20mVrms
8MHz~10MHz 30mVrms
100MHz range: 10MHz~80MHz 20mVrms
80MHz~100MHz 30mVrms
Attenuation: ×1?×20 fixed
Filter(CH1 only)Low pass: AC 100kHz-3dB
Impedance: Approximate 1MO then 35pF
Maximum voltage without damage: 250V(DC+ACrms)
Channel B
Input sensitivity: 20mVrms
Impedance: Approximate 50O
Maximun voltage without damage: 3V
Time base
Timebase frequency: 10MHz
Short term stability: ±3×10-9 for 1s average
Long term stability: 2×10-5 month
Temperature: ±1×10-5 ; 0~40?
Line voltage: ±1×10-7 for 10% change
Display: 8 digits,0.39 inch green LED display with decimal
point,gate,overflow,kHz,MHz and µs indication
Power requirement: line 220V ± 10% 45Hz~70Hz
Warm-up time: 20 minutes when cold started at 25
Temperature rated range of use: -5~50
Storage and transport: -40~60
Humidity operating: 10~90%RH
Dimension: width :207mm heigh: 85mm depth: 255mm