[time-nuts] About HP10544A

Bruce Griffiths bruce.griffiths at xtra.co.nz
Mon Mar 9 19:55:14 UTC 2009

Esa Heikkinen wrote:
> Hi Bruce,
>> White emitter follower circuit attached.
> Here are the results. First, the circuit draws 33.3 mA at 12 vols. And 
> it's gain is 1:1 as expected with emitter follower - checked that with 
> RF generator as an input just to make sure that I built it correct.
> With HP10544A the output level is below +8 dBm:
> http://www.amigazone.fi/files/gpsdo/544-10.png
> (with 2 meters of RG174 and SMA-connectors between the circuit and SA)
> Now the harmonics look like this:
> http://www.amigazone.fi/files/gpsdo/544-11.png
> And 2nd harmonic level:
> http://www.amigazone.fi/files/gpsdo/544-12.png
> So the spec told that 2nd harmonic should be more than 25 dB down, it is 
> just in spec...
> So the final result looks that the 10544A is OK but it really has this 
> kind of output spectrum?

Try increasing C2 and C8 in the white emitter follower circuit schematic
to 100nF.


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