K&K FXE / FXQE80

Company: http://www.kplusk-messtechnik.de/index.html

Installation CD “K+K FXE 18-05-08” is in the ResLab (cabinet/computer manual)!

Upgrade der Zählerkarten 2018

Die Zählerkarte FXE02 (alt) wurde zu einer FXE07 (neu) ersetzt. Die FXE02 war zu alt und konnte nicht upgegradet werden.

Sync-Fähigkeit mit PPS

Bei 1V ist Schaltschwelle

Wird als Master-Zähler verwendet

Die Zählerkarte FXE04 wurde upgegradet:

USB-LAN-Buchse

USB-Nummer: 000000EA (kann verändert werden)

Ergänzung der Sync-Verkettung

Wird weiterhin als Slave-Zählerkarte verwendet

Allgemein:

Nun können bis zu 4 unabhängige User einen Kanal benutzen

Sie können unterschiedliche Modis gleichzeitig verwenden: gemittelt/ungemittelt etc.

Der Zähler kann als TCP-Server verwendet werden

Die acht Eingänge können:

<fc #ff0000>4kHz - 132MHz</fc> zählen anstatt bis 65MHz

<fc #ff0000>~ 0dBm - 17dBm</fc>

Verbindung mit dem Computer ist mit USB und LAN möglich anstatt Serial.

Dadurch können die Kanäle schneller ausgelesen werden. Anstatt 1 Kanal 1ms (bei Serial) bis zu 8 Kanaäle jeweils 8 Kanäle 1ms (USB).

Die Möglichkeit, dass man einen zeitlichen Verlauf graphisch anzeigen kann, ist nun möglich!

New Counter

Select your measuring method

Difference between π- and Λ-measurement. Set under Report Mode:

π-measurement = Phase

Λ-measurement = Phase Average (usually)

“ Please note that I distinguish between the raw measurement results generated by the hardware, and the reports to the PC which are produced by the microprocessor.
Internally, the FXE counters continuously take raw measurements of the phase (relative to the 10MHz reference) of each channel every millisecond.
The on-board microprocessor can evaluate these raw measurements in different modes for presentation to the PC. I shall try to describe this by giving examples for each mode, where Pc(i) shall be the current raw 'P'hase measurement of channel 'c' at millisecond 'i', and I assume a report interval of 1s (=1000ms):

a) Instantaneous phase report mode: The on-board microprocessor reports to the PC at the selected report interval only the latest raw measurement result. All other intermediate results are ignored. Measurements reported (@ interval 1s) will be

Pc( i )
Pc(i+1000)
Pc(i+2000)
Pc(i+3000) ...

b) Averaged phase report mode: The on-board microprocessor calculates the average of all raw measurements taken during the report interval and reports to the PC at the end of the interval. All raw measurements contribute to the reported result. This helps to reduce measurement noise. Results reported (@ interval 1s) will be

Sum(n=0..999){Pc( i + n )}/1000
Sum(n=0..999){Pc(i+1000+n)}/1000
Sum(n=0..999){Pc(i+2000+n)}/1000
Sum(n=0..999){Pc(i+3000+n)}/1000 ...

c) Phase difference report mode: Inter-channel phase differences Pc-P1 are reported. These differences are the 'best possible' measurements, as any uncertainties of the reference cancel and most temperature effects cancel, as they are common to all channels. Measurements reported (@ interval 1s) will be

Pc( i ) - P1( i )
Pc(i+1000) - P1(i+1000)
Pc(i+2000) - P1(i+2000)
Pc(i+3000) - P1(i+3000) ...

d) Averaged phase difference report mode: Inter-channel differences of averaged phase Pc-P1 are reported. Measurements reported (@ interval 1s) will be

Sum(n=0..999){Pc( i + n ) - P1( i + n )}/1000
Sum(n=0..999){Pc(i+1000+n) - P1(i+1000+n)}/1000
Sum(n=0..999){Pc(i+2000+n) - P1(i+2000+n)}/1000
Sum(n=0..999){Pc(i+3000+n) - P1(i+3000+n)}/1000 ...

e) Frequency report mode: Frequency is Phase advance per time. The on-board microprocessor calculates the difference of the current phase measurement and the measurement taken one report interval earlier, and divides it by the report interval. Measurements reported (@ interval 1s) will be

[Pc( i ) - Pc(i-1000)]/1000ms
[Pc(i+1000) - Pc( i ) ]/1000ms
[Pc(i+2000) - Pc(i+1000)]/1000ms
[Pc(i+3000) - Pc(i+2000)]/1000ms ...

f) Averaged frequency report mode: Averaged frequency is advance of averaged phase per time. The on-board microprocessor calculates the difference of the currents averaged phase and the averaged phase calculated one report interval earlier. Measurements reported (@ interval 1s) will be

[Sum(n=0..999){Pc( i + n )} - Sum(n=0..999){Pc(i-1000+n)}]/1000ms
[Sum(n=0..999){Pc(i+1000+n)} - Sum(n=0..999){Pc( i + n ) } ]/1000ms
[Sum(n=0..999){Pc(i+2000+n)} - Sum(n=0..999){Pc(i+1000+n)}]/1000ms
[Sum(n=0..999){Pc(i+3000+n)} - Sum(n=0..999){Pc(i+2000+n)}]/1000ms ...

By just re-arranging these sums you can also write

... = Sum(n=0..999){[Pc(i+n) - Pc(i-1000+n)]/1000}

Hence, averaged frequency can be thought of either as 'advance of averaged phase' or as the average over 1000 non-averaged frequencies (@ interval 1s), in 1ms spacing.

Consequently, data measured during two(!) report intervals contribute to the averaged frequency value reported.

For understanding and communication with PTB

Old Counter

Possible range: 4kHz - 65MHz

Recommented Input: 4-17 dBm (1-5V)

Program

Default Settings: 8 Com Ports
Trimmer: Auto Trimmer
Measurement Method: Phase

Intervall length

You can change the length of the interval:

Range: ~1 ms - 1 s

For shorter length [shortest: 1ms] the memory would fill up very fast.

Don´t forget to adapt the length in the program Allan-Live with time graph!

Start a measurement

Push buttons before measurement to erase RAM:

Clear Buffer-button = Reset

Rename the data file in KK_FXE Folder

Start new measurement via “Häckchen” at Frequency