Frequency Standard System: Overview

So with the built of my watch amplifier recently I got to question myself on how do I get a stable clock reference signal?. So I decided to build a frequency standard system. Unfortunately I don’t have a Rubidium reference right now but I decided to build everything in modules, so I can swap any part of it with a better or improved variant once I obtain the parts to build them.

The whole thing will be based on Eurocards (160x100mm) mounted in a Baugruppentr├Ąger.

There will be three backplane signals for each of 10Mhz/TTL and 1PPS/TTL signals,

  • Common Signal
  • Primary Source
  • Secondary Source

The common signal will be captured by any module that needs it, the primary and secondary signals are where the modules can put their signals onto. The Supervisor Module will have a switch to select whether the primary or secondary signal get put onto the common bus.

Power supply will be 12V/500mA linear for oscillators and low-noise circuits and 5V/3A switch mode for digital logic circuits.


Supervisor Module This module will act as a power sequencer, that will ensure that the modules only get power if both the 12V and 5V supplies are present. It will furthermore allow switching between the primary and secondary reference signals.

TCXO 10MHz Mk1 This module contains a VEB Narva 10Mhz TCXO oscillator and accompanying circuitry to obtain TTL signals. It has a 10MHz/TTL 50╬ę BNC output and outputs a further 10Mhz TTL signal to the primary 10MHz backplane bus.

Universal Clock Divider Mk1 This module will divide a 10MHz input signal from the backplane into 5MHz, 1MHz, 1KHz and 1pps each as a TTL output.

32.768kHz Clock Divider Mk1 This module divides a 10MHz input signal to a 32.768kHz signal as used in watches.

Phase Comparator Mk1 This module will contain a phase comparator