[time-nuts] James Miller Stabilized 10 MHz Oscillator

[WarrenS]

Ernie

Concerning the James Miller,  "Simple GPS Stabilized 10 MHz Oscillator" 
using 10KHz from the Jupiter-T GPS, schematic posted at
http://www.jrmiller.demon.co.uk/projects/ministd/frqstd0.htm

Although the circuit is definitely made very simple by using the 10KHz. 
I feel it has gone just a bit too far, and may be contributing to the poor 
reputation of analog trackers.
The schematic posted has a very basic, easy to fix, 
shortcoming in its Phase detector that limits the performance as a GPSDO.

The basic problem is that circuit as shown does not insure that the 
phase detectors inputs stay at a constant 90 degrees.
This is generally done by providing an integrator at its output, 
and insuring that the XOR's input are truly square.

I'd bet the unit James sales has fixed that issue.

It would be very interesting to see what kind of performance this 
circuit is capable of with the detector's shortcoming removed.


Warren

**************
----- Original Message ----- 
From: <ernieperes at aol.com>
To: <time-nuts at febo.com>
Sent: Monday, November 24, 2008 5:13 AM
Subject: Re: [time-nuts] GPSDO using 100Hz


> Hii Warren,
> 
> have a look on this 
> link...http://www.jrmiller.demon.co.uk/projects/ministd/frqstd0.htm
> 
> and he is using the 10KHz...rpt 10KHz not the 100Hz......compare with 
> your circuit diagram... / I would like to see / or the other solution 
> just make the same circuit and with your testing method chk both 
> unit.......with the same OCXO....
> the jupiter eng board is still available in the German Ebay....
> 
> Rgds Ernie.
> 
>