[time-nuts] R-S Cesium standard

Bill Hawkins bill at iaxs.net
Tue Oct 26 15:04:32 UTC 2010

Didn't know that Radio Shack made Caesium standards. 

Any phase-locked loop contains an integrator that has the phase
error as its input. The output of the integrator is then amplified
to produce the control signal for the voltage-controlled oscillator.

The integrator output settles at some voltage that causes the phase
error to go to zero (until something changes). This voltage has a
range, like +/- 10 volts, where it is able to vary the VCO. When
the voltage reaches either limit, the integrator is said to be
saturated. I'd expect the Integrator meter to show the output of
the integrator. Normally, you'd trim the VCO to center the meter at

If the meter saturates in either direction, the PLL is open, which
means that the integrator output isn't getting to the VCO, or the
VCO isn't varying, or the phase detector isn't detecting, or the
integrator is bad, or anything else that would break the loop.

The Amplifier probably isn't the one after the integrator, but is
the one that amplifies the output of the physics package. In a Rb
standard, the physics package is the phase detector for the PLL.

Bill Hawkins

-----Original Message-----
From: EWKehren at aol.com
Sent: Tuesday, October 26, 2010 9:04 AM

Does any one have any info on the RS cesium standard. Specifically does
anyone know what switch position 7 Integrator and position 8 Amplifier 
measure?  Any help will be appreciated. Thank  you.
Bert Kehren

More information about the time-nuts mailing list