Frequency meter with 0.1ppm resolution

[Picuino]

Hello all,
I'm new in this forum and my native language is spanish, so sorry in advance for my language.

I'm development a new frequency meter based in a tiny PIC microcontroller (PIC16F18446) with this specifications:

Frequency range: 0.01 Hz to 15MHz
Resolution:  8 decimals per second (with CTMU external capacitor)
Precision: depends on Crystal. 0.1ppm with calibration and no temperature changes.
Input levels: between 0.8v (LOW) and 3.1V (HIGH)
Power Supply: 5 volts
Output: via LCD and serial UART.
Command Line Interface: via serial communications.

I have published all in github:
https://github.com/picuino/freqcounter


Now, I'm waiting for a designed PCB. Meanwhile I have testing all with protoboard.

Here a little pic of my lab:



Regards.

[IRFP]

Hello
Good job...
What is the OCXO model?

[Picuino]

Thank you,
The OCXO is a Piezo Technik PTOC32227 from ebay.
Is mounted on PCB designed by me.

The main reason for develop this frequency meter is:
- For fun. I love develop it.
- Make a simple and unexpensive frequency meter. You only need PIC16F18446, Xtal of 8MHz and USB-Serial interface.
- Measure low frequencies with precision. You can measure 32kHz Xtal with 7 figures of resolution (0.1 PPM resolution)
- Autocalibration with 1PPS signal of unexpensive GPS

Regards.

[Picuino]

Here, a photo showing frequency meter measuring 1 Pulse Per Second signal from a GPS.



Top reading is 1 second period measurement (1.0000000 Hz)
Low reading is 10 second period measurement (999.99997 milliHertz)

As you can see, the reading is auto ranging.

Regards.

[Picuino]

A little example of data sended via serial interface to Computer, after calibration:

Code: [Select]

Pulses= 000000000000001 Time= 000000016003955 Freq= 1,0000001 Hz Freq= 999,99997 mHz
Pulses= 000000000000001 Time= 000000016003953 Freq= 1,0000002 Hz Freq= 1,00000000 Hz
Pulses= 000000000000001 Time= 000000016003956 Freq= 1,0000000 Hz Freq= 1,00000001 Hz
Pulses= 000000000000001 Time= 000000016003955 Freq= 1,0000001 Hz Freq= 1,00000001 Hz
Pulses= 000000000000001 Time= 000000016003956 Freq= 1,0000000 Hz Freq= 1,00000002 Hz
Pulses= 000000000000001 Time= 000000016003956 Freq= 1,0000000 Hz Freq= 1,00000002 Hz
Pulses= 000000000000001 Time= 000000016003956 Freq= 1,0000000 Hz Freq= 1,00000003 Hz
Pulses= 000000000000001 Time= 000000016003956 Freq= 1,0000000 Hz Freq= 1,00000003 Hz
Pulses= 000000000000001 Time= 000000016003957 Freq= 999,9999 mHz Freq= 1,00000003 Hz
Pulses= 000000000000001 Time= 000000016003956 Freq= 1,0000000 Hz Freq= 1,00000002 Hz
Pulses= 000000000000001 Time= 000000016003957 Freq= 999,9999 mHz Freq= 999,99999 mHz
Pulses= 000000000000001 Time= 000000016003957 Freq= 999,9999 mHz Freq= 999,99999 mHz
Pulses= 000000000000001 Time= 000000016003956 Freq= 1,0000000 Hz Freq= 999,99998 mHz
Pulses= 000000000000001 Time= 000000016003957 Freq= 999,9999 mHz Freq= 999,99997 mHz
Pulses= 000000000000001 Time= 000000016003956 Freq= 1,0000000 Hz Freq= 999,99997 mHz
Pulses= 000000000000001 Time= 000000016003956 Freq= 1,0000000 Hz Freq= 999,99997 mHz
Pulses= 000000000000001 Time= 000000016003957 Freq= 999,9999 mHz Freq= 999,99997 mHz
Pulses= 000000000000001 Time= 000000016003956 Freq= 1,0000000 Hz Freq= 999,99997 mHz
Pulses= 000000000000001 Time= 000000016003957 Freq= 999,9999 mHz Freq= 999,99997 mHz
Pulses= 000000000000001 Time= 000000016003956 Freq= 1,0000000 Hz Freq= 999,99997 mHz
Pulses= 000000000000001 Time= 000000016003957 Freq= 999,9999 mHz Freq= 999,99997 mHz
Pulses= 000000000000001 Time= 000000016003957 Freq= 999,9999 mHz Freq= 999,99997 mHz
Pulses= 000000000000001 Time= 000000016003956 Freq= 1,0000000 Hz Freq= 999,99997 mHz
Pulses= 000000000000001 Time= 000000016003957 Freq= 999,9999 mHz Freq= 999,99997 mHz
Pulses= 000000000000001 Time= 000000016003956 Freq= 1,0000000 Hz Freq= 999,99997 mHz
Pulses= 000000000000001 Time= 000000016003957 Freq= 999,9999 mHz Freq= 999,99997 mHz
Pulses= 000000000000001 Time= 000000016003956 Freq= 1,0000000 Hz Freq= 999,99997 mHz
Pulses= 000000000000001 Time= 000000016003957 Freq= 999,9999 mHz Freq= 999,99997 mHz
Pulses= 000000000000001 Time= 000000016003957 Freq= 999,9999 mHz Freq= 999,99996 mHz
Pulses= 000000000000001 Time= 000000016003956 Freq= 1,0000000 Hz Freq= 999,99997 mHz
Pulses= 000000000000001 Time= 000000016003957 Freq= 999,9999 mHz Freq= 999,99997 mHz
Pulses= 000000000000001 Time= 000000016003956 Freq= 1,0000000 Hz Freq= 999,99997 mHz
Pulses= 000000000000001 Time= 000000016003957 Freq= 999,9999 mHz Freq= 999,99997 mHz
Pulses= 000000000000001 Time= 000000016003957 Freq= 999,9999 mHz Freq= 999,99996 mHz
Pulses= 000000000000001 Time= 000000016003956 Freq= 1,0000000 Hz Freq= 999,99997 mHz
Pulses= 000000000000001 Time= 000000016003957 Freq= 999,9999 mHz Freq= 999,99996 mHz
Pulses= 000000000000001 Time= 000000016003956 Freq= 1,0000000 Hz Freq= 999,99997 mHz
Pulses= 000000000000001 Time= 000000016003953 Freq= 1,0000002 Hz Freq= 999,99999 mHz
Pulses= 000000000000001 Time= 000000016003956 Freq= 1,0000000 Hz Freq= 999,99999 mHz
Pulses= 000000000000001 Time= 000000016003957 Freq= 999,9999 mHz Freq= 999,99999 mHz
Pulses= 000000000000001 Time= 000000016003957 Freq= 999,9999 mHz Freq= 999,99999 mHz
Pulses= 000000000000001 Time= 000000016003956 Freq= 1,0000000 Hz Freq= 999,99999 mHz
Pulses= 000000000000001 Time= 000000016003958 Freq= 999,9999 mHz Freq= 999,99999 mHz
Pulses= 000000000000001 Time= 000000016003957 Freq= 999,9999 mHz Freq= 999,99998 mHz
Pulses= 000000000000001 Time= 000000016003957 Freq= 999,9999 mHz Freq= 999,99998 mHz
Pulses= 000000000000001 Time= 000000016003957 Freq= 999,9999 mHz Freq= 999,99997 mHz
Pulses= 000000000000001 Time= 000000016003957 Freq= 999,9999 mHz Freq= 999,99994 mHz
Pulses= 000000000000001 Time= 000000016003956 Freq= 1,0000000 Hz Freq= 999,99994 mHz
Pulses= 000000000000001 Time= 000000016003957 Freq= 999,9999 mHz Freq= 999,99994 mHz
Pulses= 000000000000001 Time= 000000016003957 Freq= 999,9999 mHz Freq= 999,99994 mHz
Pulses= 000000000000001 Time= 000000016003958 Freq= 999,9999 mHz Freq= 999,99993 mHz
Pulses= 000000000000001 Time= 000000016003957 Freq= 999,9999 mHz Freq= 999,99994 mHz
Pulses= 000000000000001 Time= 000000016003956 Freq= 1,0000000 Hz Freq= 999,99994 mHz
Pulses= 000000000000001 Time= 000000016003957 Freq= 999,9999 mHz Freq= 999,99994 mHz
Pulses= 000000000000001 Time= 000000016003957 Freq= 999,9999 mHz Freq= 999,99994 mHz
Pulses= 000000000000001 Time= 000000016003957 Freq= 999,9999 mHz Freq= 999,99994 mHz
Pulses= 000000000000001 Time= 000000016003957 Freq= 999,9999 mHz Freq= 999,99994 mHz
Pulses= 000000000000001 Time= 000000016003957 Freq= 999,9999 mHz Freq= 999,99994 mHz
Pulses= 000000000000001 Time= 000000016003957 Freq= 999,9999 mHz Freq= 999,99994 mHz
Pulses= 000000000000001 Time= 000000016003957 Freq= 999,9999 mHz Freq= 999,99994 mHz
Pulses= 000000000000001 Time= 000000016003957 Freq= 999,9999 mHz Freq= 999,99994 mHz
Pulses= 000000000000001 Time= 000000016003957 Freq= 999,9999 mHz Freq= 999,99994 mHz
Pulses= 000000000000001 Time= 000000016003957 Freq= 999,9999 mHz Freq= 999,99994 mHz
Pulses= 000000000000001 Time= 000000016003957 Freq= 999,9999 mHz Freq= 999,99994 mHz
Pulses= 000000000000001 Time= 000000016003957 Freq= 999,9999 mHz Freq= 999,99994 mHz
Pulses= 000000000000001 Time= 000000016003957 Freq= 999,9999 mHz Freq= 999,99994 mHz
Pulses= 000000000000001 Time= 000000016003957 Freq= 999,9999 mHz Freq= 999,99994 mHz
Pulses= 000000000000001 Time= 000000016003957 Freq= 999,9999 mHz Freq= 999,99994 mHz
Pulses= 000000000000001 Time= 000000016003957 Freq= 999,9999 mHz Freq= 999,99994 mHz
Pulses= 000000000000001 Time= 000000016003957 Freq= 999,9999 mHz Freq= 999,99994 mHz
Pulses= 000000000000001 Time= 000000016003957 Freq= 999,9999 mHz Freq= 999,99994 mHz
Pulses= 000000000000001 Time= 000000016003957 Freq= 999,9999 mHz Freq= 999,99994 mHz
Pulses= 000000000000001 Time= 000000016003957 Freq= 999,9999 mHz Freq= 999,99994 mHz
Pulses= 000000000000001 Time= 000000016003957 Freq= 999,9999 mHz Freq= 999,99994 mHz
Pulses= 000000000000001 Time= 000000016003956 Freq= 1,0000000 Hz Freq= 999,99994 mHz
Pulses= 000000000000001 Time= 000000016003958 Freq= 999,9999 mHz Freq= 999,99994 mHz
Pulses= 000000000000001 Time= 000000016003956 Freq= 1,0000000 Hz Freq= 999,99994 mHz
Pulses= 000000000000001 Time= 000000016003957 Freq= 999,9999 mHz Freq= 999,99994 mHz
Pulses= 000000000000001 Time= 000000016003958 Freq= 999,9999 mHz Freq= 999,99994 mHz
Pulses= 000000000000001 Time= 000000016003957 Freq= 999,9999 mHz Freq= 999,99994 mHz
Pulses= 000000000000001 Time= 000000016003957 Freq= 999,9999 mHz Freq= 999,99994 mHz
Pulses= 000000000000001 Time= 000000016003957 Freq= 999,9999 mHz Freq= 999,99994 mHz
Pulses= 000000000000001 Time= 000000016003957 Freq= 999,9999 mHz Freq= 999,99994 mHz
Pulses= 000000000000001 Time= 000000016003957 Freq= 999,9999 mHz Freq= 999,99993 mHz
Pulses= 000000000000001 Time= 000000016003956 Freq= 1,0000000 Hz Freq= 999,99994 mHz


First column: number of pulses divided by 2 (prescaler of 1:2)
Second column: time measured as number of clock cycles (at 8MHz)
Third column: Frequency at 1 second period
Fourth column:  Frequency at 10 second period

hope to improve stability mounting it on PCB.

Regards.

[Picuino]

In order to maintain precision at lower frequencies, the core of frequency meter performs a reciprocal counting.

Microcontroller measure both pulses in the input and cycles of main xtal clock. Readings of clock cycles are taken exactly at rise time of input signal (both measurements are syncronized).

After measure of time (in xtal cycles) and measure of pulses, the frequency meter performs this calculation:

   Frequency = prescaler_divisor * Xtal_frequency * Input_Pulses / xtal_cycles

To maintain precision, calculations are made with 48 bits integer and 48 bit float routines (implemented in c software)

[Picuino]

Two simultaneous inputs

I have just made an improvement of the software for measure 2 signals simultaneously.
In this case, an OCXO of 10MHz and a 1PPS signal of GPS.



Top reading, Input A = GPS
Bottom reading, Input B = OCXO


And now I have found a problem with this mode of operation (2 inputs).
If a input  A or input B have no signal, the frequency meter stops waiting for income pulse. So, i need change the mode of operation if I need measure of only one signal. I will think more about this.

In other hand, I hope for more resolution results (1 digit more) when I will mount all in PCB.

[Picuino]

New test.
I have mounted two OCXO this time.

One OCXO supplies 5MHz to the microcontroller system clock.
The other OCXO supplies a 1PPS signal (1Hz)

The blue module is a gps with other 1PPS signal.

The frequency meter measure both signals of 1PPS working with 5MHz of stable system clock.

The method of period measurement is continuous timestamping and the method of calculate frequencies is reciprocal counting
continuous timestamping can increase resolution in long term averages.

[Picuino]

Raw data of first seconds

Code: [Select]

Pulses A= 000000000000002 Time A= 000000009999996 Freq. A= 999,9999E-3 Freq. A= 999,99982E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999997 Freq. A= 999,9998E-3 Freq. A= 999,99984E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999996 Freq. A= 999,9999E-3 Freq. A= 999,99984E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999997 Freq. A= 999,9998E-3 Freq. A= 999,99984E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999997 Freq. A= 999,9998E-3 Freq. A= 999,99982E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99980E-3
Pulses A= 000000000000002 Time A= 000000009999996 Freq. A= 999,9999E-3 Freq. A= 999,99984E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99980E-3
Pulses A= 000000000000002 Time A= 000000009999997 Freq. A= 999,9998E-3 Freq. A= 999,99982E-3 Pulses B= 000000000000002 Time B= 000000009999998 Freq. B= 999,9997E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999996 Freq. A= 999,9999E-3 Freq. A= 999,99984E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999997 Freq. A= 999,9998E-3 Freq. A= 999,99982E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999997 Freq. A= 999,9998E-3 Freq. A= 999,99984E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999996 Freq. A= 999,9999E-3 Freq. A= 999,99984E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999997 Freq. A= 999,9998E-3 Freq. A= 999,99984E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99980E-3
Pulses A= 000000000000002 Time A= 000000009999997 Freq. A= 999,9998E-3 Freq. A= 999,99984E-3 Pulses B= 000000000000002 Time B= 000000009999998 Freq. B= 999,9997E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999997 Freq. A= 999,9998E-3 Freq. A= 999,99984E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999996 Freq. A= 999,9999E-3 Freq. A= 999,99984E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999997 Freq. A= 999,9998E-3 Freq. A= 999,99984E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999996 Freq. A= 999,9999E-3 Freq. A= 999,99984E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999997 Freq. A= 999,9998E-3 Freq. A= 999,99982E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99980E-3
Pulses A= 000000000000002 Time A= 000000009999997 Freq. A= 999,9998E-3 Freq. A= 999,99982E-3 Pulses B= 000000000000002 Time B= 000000009999998 Freq. B= 999,9997E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999996 Freq. A= 999,9999E-3 Freq. A= 999,99984E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999997 Freq. A= 999,9998E-3 Freq. A= 999,99982E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999997 Freq. A= 999,9998E-3 Freq. A= 999,99984E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999996 Freq. A= 999,9999E-3 Freq. A= 999,99984E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999997 Freq. A= 999,9998E-3 Freq. A= 999,99984E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99980E-3
Pulses A= 000000000000002 Time A= 000000009999997 Freq. A= 999,9998E-3 Freq. A= 999,99984E-3 Pulses B= 000000000000002 Time B= 000000009999998 Freq. B= 999,9997E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999996 Freq. A= 999,9999E-3 Freq. A= 999,99984E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999997 Freq. A= 999,9998E-3 Freq. A= 999,99982E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999997 Freq. A= 999,9998E-3 Freq. A= 999,99984E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999996 Freq. A= 999,9999E-3 Freq. A= 999,99984E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999997 Freq. A= 999,9998E-3 Freq. A= 999,99982E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99980E-3
Pulses A= 000000000000002 Time A= 000000009999997 Freq. A= 999,9998E-3 Freq. A= 999,99984E-3 Pulses B= 000000000000002 Time B= 000000009999998 Freq. B= 999,9997E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999996 Freq. A= 999,9999E-3 Freq. A= 999,99984E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999997 Freq. A= 999,9998E-3 Freq. A= 999,99982E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999996 Freq. A= 999,9999E-3 Freq. A= 999,99984E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999997 Freq. A= 999,9998E-3 Freq. A= 999,99984E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999997 Freq. A= 999,9998E-3 Freq. A= 999,99982E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99980E-3
Pulses A= 000000000000002 Time A= 000000009999996 Freq. A= 999,9999E-3 Freq. A= 999,99984E-3 Pulses B= 000000000000002 Time B= 000000009999998 Freq. B= 999,9997E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999997 Freq. A= 999,9998E-3 Freq. A= 999,99984E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999997 Freq. A= 999,9998E-3 Freq. A= 999,99984E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999996 Freq. A= 999,9999E-3 Freq. A= 999,99984E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999997 Freq. A= 999,9998E-3 Freq. A= 999,99984E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999997 Freq. A= 999,9998E-3 Freq. A= 999,99984E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99980E-3
Pulses A= 000000000000002 Time A= 000000009999996 Freq. A= 999,9999E-3 Freq. A= 999,99984E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99980E-3
Pulses A= 000000000000002 Time A= 000000009999997 Freq. A= 999,9998E-3 Freq. A= 999,99982E-3 Pulses B= 000000000000002 Time B= 000000009999998 Freq. B= 999,9997E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999996 Freq. A= 999,9999E-3 Freq. A= 999,99984E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999997 Freq. A= 999,9998E-3 Freq. A= 999,99984E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999997 Freq. A= 999,9998E-3 Freq. A= 999,99982E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999996 Freq. A= 999,9999E-3 Freq. A= 999,99984E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999997 Freq. A= 999,9998E-3 Freq. A= 999,99984E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99980E-3
Pulses A= 000000000000002 Time A= 000000009999997 Freq. A= 999,9998E-3 Freq. A= 999,99984E-3 Pulses B= 000000000000002 Time B= 000000009999998 Freq. B= 999,9997E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999997 Freq. A= 999,9998E-3 Freq. A= 999,99984E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999996 Freq. A= 999,9999E-3 Freq. A= 999,99984E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999997 Freq. A= 999,9998E-3 Freq. A= 999,99984E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999996 Freq. A= 999,9999E-3 Freq. A= 999,99984E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999997 Freq. A= 999,9998E-3 Freq. A= 999,99982E-3 Pulses B= 000000000000002 Time B= 000000009999998 Freq. B= 999,9997E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999997 Freq. A= 999,9998E-3 Freq. A= 999,99982E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999996 Freq. A= 999,9999E-3 Freq. A= 999,99984E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999997 Freq. A= 999,9998E-3 Freq. A= 999,99982E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999997 Freq. A= 999,9998E-3 Freq. A= 999,99984E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999996 Freq. A= 999,9999E-3 Freq. A= 999,99984E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99980E-3
Pulses A= 000000000000002 Time A= 000000009999997 Freq. A= 999,9998E-3 Freq. A= 999,99984E-3 Pulses B= 000000000000002 Time B= 000000009999998 Freq. B= 999,9997E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999997 Freq. A= 999,9998E-3 Freq. A= 999,99984E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999996 Freq. A= 999,9999E-3 Freq. A= 999,99984E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999997 Freq. A= 999,9998E-3 Freq. A= 999,99982E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999997 Freq. A= 999,9998E-3 Freq. A= 999,99984E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999996 Freq. A= 999,9999E-3 Freq. A= 999,99984E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99980E-3
Pulses A= 000000000000002 Time A= 000000009999997 Freq. A= 999,9998E-3 Freq. A= 999,99982E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99980E-3
Pulses A= 000000000000002 Time A= 000000009999997 Freq. A= 999,9998E-3 Freq. A= 999,99984E-3 Pulses B= 000000000000002 Time B= 000000009999998 Freq. B= 999,9997E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999996 Freq. A= 999,9999E-3 Freq. A= 999,99984E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999997 Freq. A= 999,9998E-3 Freq. A= 999,99982E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999997 Freq. A= 999,9998E-3 Freq. A= 999,99984E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999996 Freq. A= 999,9999E-3 Freq. A= 999,99984E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999997 Freq. A= 999,9998E-3 Freq. A= 999,99982E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99980E-3
Pulses A= 000000000000002 Time A= 000000009999997 Freq. A= 999,9998E-3 Freq. A= 999,99984E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99980E-3
Pulses A= 000000000000002 Time A= 000000009999996 Freq. A= 999,9999E-3 Freq. A= 999,99984E-3 Pulses B= 000000000000002 Time B= 000000009999998 Freq. B= 999,9997E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999997 Freq. A= 999,9998E-3 Freq. A= 999,99982E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999996 Freq. A= 999,9999E-3 Freq. A= 999,99984E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999997 Freq. A= 999,9998E-3 Freq. A= 999,99984E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999997 Freq. A= 999,9998E-3 Freq. A= 999,99982E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999997 Freq. A= 999,9998E-3 Freq. A= 999,99984E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99980E-3
Pulses A= 000000000000002 Time A= 000000009999996 Freq. A= 999,9999E-3 Freq. A= 999,99984E-3 Pulses B= 000000000000002 Time B= 000000009999998 Freq. B= 999,9997E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999997 Freq. A= 999,9998E-3 Freq. A= 999,99984E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999996 Freq. A= 999,9999E-3 Freq. A= 999,99984E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999997 Freq. A= 999,9998E-3 Freq. A= 999,99984E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999997 Freq. A= 999,9998E-3 Freq. A= 999,99982E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999996 Freq. A= 999,9999E-3 Freq. A= 999,99984E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99980E-3
Pulses A= 000000000000002 Time A= 000000009999997 Freq. A= 999,9998E-3 Freq. A= 999,99982E-3 Pulses B= 000000000000002 Time B= 000000009999998 Freq. B= 999,9997E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999997 Freq. A= 999,9998E-3 Freq. A= 999,99984E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999996 Freq. A= 999,9999E-3 Freq. A= 999,99984E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999997 Freq. A= 999,9998E-3 Freq. A= 999,99984E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999997 Freq. A= 999,9998E-3 Freq. A= 999,99984E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999996 Freq. A= 999,9999E-3 Freq. A= 999,99984E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99980E-3
Pulses A= 000000000000002 Time A= 000000009999997 Freq. A= 999,9998E-3 Freq. A= 999,99982E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99980E-3
Pulses A= 000000000000002 Time A= 000000009999997 Freq. A= 999,9998E-3 Freq. A= 999,99984E-3 Pulses B= 000000000000002 Time B= 000000009999998 Freq. B= 999,9997E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999997 Freq. A= 999,9998E-3 Freq. A= 999,99984E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999996 Freq. A= 999,9999E-3 Freq. A= 999,99982E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999996 Freq. A= 999,9999E-3 Freq. A= 999,99984E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999997 Freq. A= 999,9998E-3 Freq. A= 999,99984E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999997 Freq. A= 999,9998E-3 Freq. A= 999,99982E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99980E-3
Pulses A= 000000000000002 Time A= 000000009999997 Freq. A= 999,9998E-3 Freq. A= 999,99982E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99980E-3
Pulses A= 000000000000002 Time A= 000000009999996 Freq. A= 999,9999E-3 Freq. A= 999,99984E-3 Pulses B= 000000000000002 Time B= 000000009999998 Freq. B= 999,9997E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999997 Freq. A= 999,9998E-3 Freq. A= 999,99984E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999996 Freq. A= 999,9999E-3 Freq. A= 999,99984E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999997 Freq. A= 999,9998E-3 Freq. A= 999,99984E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999997 Freq. A= 999,9998E-3 Freq. A= 999,99984E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999996 Freq. A= 999,9999E-3 Freq. A= 999,99984E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99980E-3
Pulses A= 000000000000002 Time A= 000000009999997 Freq. A= 999,9998E-3 Freq. A= 999,99982E-3 Pulses B= 000000000000002 Time B= 000000009999998 Freq. B= 999,9997E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999997 Freq. A= 999,9998E-3 Freq. A= 999,99984E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999997 Freq. A= 999,9998E-3 Freq. A= 999,99984E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999996 Freq. A= 999,9999E-3 Freq. A= 999,99984E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999997 Freq. A= 999,9998E-3 Freq. A= 999,99984E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999997 Freq. A= 999,9998E-3 Freq. A= 999,99984E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99980E-3
Pulses A= 000000000000002 Time A= 000000009999996 Freq. A= 999,9999E-3 Freq. A= 999,99982E-3 Pulses B= 000000000000002 Time B= 000000009999998 Freq. B= 999,9997E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999997 Freq. A= 999,9998E-3 Freq. A= 999,99982E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999996 Freq. A= 999,9999E-3 Freq. A= 999,99984E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999997 Freq. A= 999,9998E-3 Freq. A= 999,99982E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999996 Freq. A= 999,9999E-3 Freq. A= 999,99982E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999997 Freq. A= 999,9998E-3 Freq. A= 999,99984E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99980E-3
Pulses A= 000000000000002 Time A= 000000009999997 Freq. A= 999,9998E-3 Freq. A= 999,99984E-3 Pulses B= 000000000000002 Time B= 000000009999998 Freq. B= 999,9997E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999997 Freq. A= 999,9998E-3 Freq. A= 999,99984E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999996 Freq. A= 999,9999E-3 Freq. A= 999,99984E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999997 Freq. A= 999,9998E-3 Freq. A= 999,99986E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999997 Freq. A= 999,9998E-3 Freq. A= 999,99984E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999996 Freq. A= 999,9999E-3 Freq. A= 999,99984E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99980E-3
Pulses A= 000000000000002 Time A= 000000009999997 Freq. A= 999,9998E-3 Freq. A= 999,99982E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99980E-3
Pulses A= 000000000000002 Time A= 000000009999996 Freq. A= 999,9999E-3 Freq. A= 999,99984E-3 Pulses B= 000000000000002 Time B= 000000009999998 Freq. B= 999,9997E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999997 Freq. A= 999,9998E-3 Freq. A= 999,99982E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999997 Freq. A= 999,9998E-3 Freq. A= 999,99982E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999996 Freq. A= 999,9999E-3 Freq. A= 999,99984E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999997 Freq. A= 999,9998E-3 Freq. A= 999,99984E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999996 Freq. A= 999,9999E-3 Freq. A= 999,99984E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99980E-3
Pulses A= 000000000000002 Time A= 000000009999998 Freq. A= 999,9997E-3 Freq. A= 999,99984E-3 Pulses B= 000000000000002 Time B= 000000009999998 Freq. B= 999,9997E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999996 Freq. A= 999,9999E-3 Freq. A= 999,99984E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999996 Freq. A= 999,9999E-3 Freq. A= 999,99984E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999998 Freq. A= 999,9997E-3 Freq. A= 999,99984E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999996 Freq. A= 999,9999E-3 Freq. A= 999,99984E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999996 Freq. A= 999,9999E-3 Freq. A= 999,99982E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99980E-3
Pulses A= 000000000000002 Time A= 000000009999997 Freq. A= 999,9998E-3 Freq. A= 999,99984E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99980E-3
Pulses A= 000000000000002 Time A= 000000009999997 Freq. A= 999,9998E-3 Freq. A= 999,99984E-3 Pulses B= 000000000000002 Time B= 000000009999998 Freq. B= 999,9997E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999997 Freq. A= 999,9998E-3 Freq. A= 999,99982E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999997 Freq. A= 999,9998E-3 Freq. A= 999,99982E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999996 Freq. A= 999,9999E-3 Freq. A= 999,99986E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999997 Freq. A= 999,9998E-3 Freq. A= 999,99984E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999996 Freq. A= 999,9999E-3 Freq. A= 999,99982E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99980E-3
Pulses A= 000000000000002 Time A= 000000009999997 Freq. A= 999,9998E-3 Freq. A= 999,99984E-3 Pulses B= 000000000000002 Time B= 000000009999998 Freq. B= 999,9997E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999996 Freq. A= 999,9999E-3 Freq. A= 999,99982E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999997 Freq. A= 999,9998E-3 Freq. A= 999,99982E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999997 Freq. A= 999,9998E-3 Freq. A= 999,99982E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999997 Freq. A= 999,9998E-3 Freq. A= 999,99984E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999996 Freq. A= 999,9999E-3 Freq. A= 999,99984E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99980E-3
Pulses A= 000000000000002 Time A= 000000009999997 Freq. A= 999,9998E-3 Freq. A= 999,99986E-3 Pulses B= 000000000000002 Time B= 000000009999998 Freq. B= 999,9997E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999997 Freq. A= 999,9998E-3 Freq. A= 999,99984E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999996 Freq. A= 999,9999E-3 Freq. A= 999,99984E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999997 Freq. A= 999,9998E-3 Freq. A= 999,99982E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999996 Freq. A= 999,9999E-3 Freq. A= 999,99984E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999997 Freq. A= 999,9998E-3 Freq. A= 999,99982E-3 Pulses B= 000000000000002 Time B= 000000009999998 Freq. B= 999,9997E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999997 Freq. A= 999,9998E-3 Freq. A= 999,99982E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999996 Freq. A= 999,9999E-3 Freq. A= 999,99984E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999997 Freq. A= 999,9998E-3 Freq. A= 999,99984E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999997 Freq. A= 999,9998E-3 Freq. A= 999,99984E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999996 Freq. A= 999,9999E-3 Freq. A= 999,99984E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99980E-3
Pulses A= 000000000000002 Time A= 000000009999997 Freq. A= 999,9998E-3 Freq. A= 999,99984E-3 Pulses B= 000000000000002 Time B= 000000009999998 Freq. B= 999,9997E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999997 Freq. A= 999,9998E-3 Freq. A= 999,99984E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999996 Freq. A= 999,9999E-3 Freq. A= 999,99984E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999997 Freq. A= 999,9998E-3 Freq. A= 999,99982E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999996 Freq. A= 999,9999E-3 Freq. A= 999,99984E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999997 Freq. A= 999,9998E-3 Freq. A= 999,99984E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99980E-3
Pulses A= 000000000000002 Time A= 000000009999997 Freq. A= 999,9998E-3 Freq. A= 999,99982E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99980E-3
Pulses A= 000000000000002 Time A= 000000009999996 Freq. A= 999,9999E-3 Freq. A= 999,99984E-3 Pulses B= 000000000000002 Time B= 000000009999998 Freq. B= 999,9997E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999997 Freq. A= 999,9998E-3 Freq. A= 999,99984E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999997 Freq. A= 999,9998E-3 Freq. A= 999,99984E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999996 Freq. A= 999,9999E-3 Freq. A= 999,99984E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999997 Freq. A= 999,9998E-3 Freq. A= 999,99984E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999997 Freq. A= 999,9998E-3 Freq. A= 999,99984E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99980E-3
Pulses A= 000000000000002 Time A= 000000009999996 Freq. A= 999,9999E-3 Freq. A= 999,99984E-3 Pulses B= 000000000000002 Time B= 000000009999998 Freq. B= 999,9997E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999997 Freq. A= 999,9998E-3 Freq. A= 999,99982E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999997 Freq. A= 999,9998E-3 Freq. A= 999,99984E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999996 Freq. A= 999,9999E-3 Freq. A= 999,99984E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999997 Freq. A= 999,9998E-3 Freq. A= 999,99982E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999997 Freq. A= 999,9998E-3 Freq. A= 999,99984E-3 Pulses B= 000000000000002 Time B= 000000009999998 Freq. B= 999,9997E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999996 Freq. A= 999,9999E-3 Freq. A= 999,99984E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999997 Freq. A= 999,9998E-3 Freq. A= 999,99982E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999997 Freq. A= 999,9998E-3 Freq. A= 999,99984E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999996 Freq. A= 999,9999E-3 Freq. A= 999,99984E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999997 Freq. A= 999,9998E-3 Freq. A= 999,99982E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99980E-3
Pulses A= 000000000000002 Time A= 000000009999997 Freq. A= 999,9998E-3 Freq. A= 999,99984E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99980E-3
Pulses A= 000000000000002 Time A= 000000009999996 Freq. A= 999,9999E-3 Freq. A= 999,99984E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99980E-3
Pulses A= 000000000000002 Time A= 000000009999997 Freq. A= 999,9998E-3 Freq. A= 999,99982E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99980E-3
Pulses A= 000000000000002 Time A= 000000009999996 Freq. A= 999,9999E-3 Freq. A= 999,99984E-3 Pulses B= 000000000000002 Time B= 000000009999998 Freq. B= 999,9997E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999997 Freq. A= 999,9998E-3 Freq. A= 999,99984E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99978E-3
Pulses A= 000000000000002 Time A= 000000009999997 Freq. A= 999,9998E-3 Freq. A= 999,99982E-3 Pulses B= 000000000000002 Time B= 000000009999997 Freq. B= 999,9998E-3 Freq. B= 999,99978E-3


[Picuino]

I will try to use Timelab or Stable32 for analyze periods and frequency.

[Kleinstein]

Continuous time stamping can really help, but how good it works depends on the type of noise. For phase type noise (e.g. trigger noise) using multiple time stamps can improve the noise. For true frequency noise (e.g. unstable oscillator) using the first and last time stamp and this the classical reciprocal  way is lower noise. So both methods have there justification.

Things may get simpler if the µC is directly running of the stable clock.

[Picuino]

Continuous timestamping allow to average last 10 periods for calculate long term frequency (with reciprocal counting method)

The frequency meter have a buffer with the last 11 timestamps and input pulses counted. With this, it can calculate frequency with 8 decimals (0.02 ppm at 5MHz clock) of resolution without error (if timebases are stable)

I was trying to test this long term frequency method and the result is that works fine. It shows 8 decimals of correct and stable frequency.

[Kleinstein]

I see continuous time stamping  as the method to take the time for every trigger of the input signal divided down to a frequency the system can handle. There are still different ways to look at these data.

The simple version is using it as a kind of running average filter for simple reciprocal counting. That is use the first and last time stamp for the interval in question to calculate the period length.

The other extreme is to use all time stamps in the interval in question and do a linear interpolation and use the slope as the result for the period. This last method can give even higher resolution, but it depends if this is actually better.  As an intermediate one could use several time-stamps from the start and stop with different weights (e.g. in between the  1,0,.....,0,-1 for single start / stop  and  N,N-1,....,1-N,-N for the linear slope).

[Picuino]

Linear interpolation takes too much memory, time and computing power. Therefore I have decided not to implement it.

[Picuino]

I have tested the frequency meter with normal quartz crystal oscillator measuring a 10kHz from OCXO.

The freqmeter can measure with 8 digits of resolution in 10 seconds averages.

[Picuino]

Other test.
I have increased the resolution by one more decimal. The method is based on charging a capacitor during the time between the rise of the input edge and the capture of counters.

With this method,  the frequency meter have a resolution of 10ns  (8 decimal digits per second). The resolution now is 0.01ppm per second.

Attached Allan Deviation and frequency measured.

[Picuino]

A photograph of the experiment.

[mino-fm]

Linear interpolation takes too much memory, time and computing power. Therefore I have decided not to implement it.

There is no need for much RAM but your µC should be able to handle double variabels (64 bit) in a fast way. 1000 stamps/s "could" improve the result by factor 30.

BUT:

Continuous time stamping can really help, but how good it works depends on the type of noise. For phase type noise (e.g. trigger noise) using multiple time stamps can improve the noise

I've tried to use linear regression over 1000 time stamps/s using (noisy) TDC7200 for start/stop-interpolation and STM32H7xx. Using different algorithms the results were not as good as using the mean value of these 1000 stamps.
Hoping 1E6 time stamps/s using STM32H750 with internal capture-timer @240 MHz without further interpolation could improve resolution failed too :-(

Other test.
I have increased the resolution by one more decimal. The method is based on charging a capacitor during the time between the rise of the input edge and the capture of counters.

With this method,  the frequency meter have a resolution of 10ns  (8 decimal digits per second). The resolution now is 0.01ppm per second.

Using a µC with fast internal timers (>=100 MHz) will give you 8 digits/s without additional hardware.

[Kleinstein]

The linear interpolation / use of multiple time stamps help against phase noise, but it does not help again true frequency noise. So it depends on the signal to measure. The effect is also limited, as usually there are both noise types and once the phase noise is suppressed enough the the other noise takes over and thus no more improvement. Chances are one could be better of averaging some 10-100 time stamps for the start and stop than the full linear interpolation. In my implementation I use averaging over the first and last 1/8th (not sure about the exact fraction) the time or a maximum of 256 time stamps.
For something like the 50 Hz mains signal it works quite good. For something like a higher frequency oscillator signal it does not help very much, as the trigger signal can be quite accurate. Here extra resolution from interpolation is likely more effective, though averaging can still help a little.

@Picuino:
The picture looks like the µC runs off a simple crystal and there is an extra precision clock. Wouldn't it be easier if the µC directly runs of the precision clock. This would eliminate one measurement.

[Picuino]

In the picture the simple crystal of 8Mhz is not working. I am injecting a 5MHz signal onto it, coming from the OCXO.
The other OCXO gives other signal of 5MHz to the input A.

The result is very accurate with both OCXO. But I do this to test that the microcontroller works exactly. In the end I want to make everything work with a simple crystal, which will be the one that limits the accuracy. I want to make a cheap frequency counter, capable of tuning 32kHz crystals for example with 1ppm acuracy (2 seconds per month)

[Picuino]

I have to take a decision.
I want to modify the PCB to make a Shield for Arduino with the frequency meter, without LCD display.
With this, the frequency meter would be cheaper and further simplified by taking advantage of the Arduino's power supply and its USB-serial connection.
On the other hand, the frequency meter would need a PC to work, since it no longer had an LCD display.

Do you think it would be a good idea to do that?

[maat]

In my opinion, I would always take the step an separate the measurement board from the frontend/display. The reason is simple. Typically the measurement board will only change slightly once development is complete. The frontend on the other hand might see a change to a bigger or different display, an entirely difference board, like an Arduino, or CAN bus driver, etc...

It also makes testing a lot easier, because the finished measurement board can be hooked up to a test bench and some automated test sequence can be run against it.

Therefore I always design two separate boards with two MCUs and they talk eg. via I²C. The added cost is typically offset by the time saved.

[Picuino]

Ok, I can prepare a serial output for a serial display LCD.

[Picuino]

Using a µC with fast internal timers (>=100 MHz) will give you 8 digits/s without additional hardware.

I have it listed as a pending task. I have a nucleo board (STM32L412) with 80MHz clock and advanced capabilities for mathematical calculations.

[Picuino]

Today I'm testing with the ZCD input.
Those acronyms mean Zero Cross Detection and it is the name of an internal module of the PIC microcontroller.
This module detects zero crossing of a sinusoidal signal and allows its frequency to be accurately measured.
It can measure the frequency of power grid (with the sinusoidal output of a transformer), or you can measure the frequency of audio signal.
In general, it is used to measure low frequencies of sine waves
On the other hand, the frequency limit is above 1MHZ, which gives a fairly high usage range.

Regards.