[time-nuts] E1938A oscillator pinning

Bruce Griffiths bruce.griffiths at xtra.co.nz
Mon Aug 27 23:54:20 UTC 2007


SAIDJACK at aol.com wrote:
>
> Thanks Bruce,
>  
> I hooked +12V and +5V up to it, but there is no  heater current, and no LED's 
> go on. There is however a small current into  the +12V (90mA) and the 10.0MHz 
> are being generated with a  significant error since the crystal is at room 
> temp.
>
> Wonder what I am doing wrong?
>  
> bye,
> Said 
>
>   
Said

Yes with the oven cold the frequency error is much larger than for an AT
crystal.
One LED on the front of the PCB flashes green when the device is powered
up OK, another glows orange until the oven reaches temperature.
The LED near the input connector glows green.

LEDS near front of board:

Amber     OFF          |
                                  |
OFF       Green          |
_________________

The oven current is quite high at startup.
The GPSDXO version requires around 24V@ 60W to startup (it has dc-dc
converters on the main board to produce +12V, +12V etc).

Amber led starts ON then after a while it flashes.
Then it turns off when OVEN is at operating temperature.
The green LED flashes throughout.
The other 2 LEDS indicate other conditions.

Bruce




More information about the Time-nuts_lists.febo.com mailing list