[time-nuts] Re: ammonia, cesium, masers, etc.

[Lux, Jim]

On 9/20/21 10:21 AM, Andy Talbot wrote:
> It ought to be possible to find the resonance with off the shelf equipment
> An ADF5355 synthesizer is capable of small frequency steps and will
> generate up to 13.6GHz.  Use it's 2nd harmonic leakage (4th harm of the
> VCO), there is a bit coming out at 24GHz.   If the synth  reference input
> is derived from a 48 bit DDS like an AD9852, it can be tuned in really
> small frequency steps, far below the 1Hz steps that ought to be enough to
> spot the absorbtion.   Isn't Caesium about 1Hz wide ?
>
> For detection, an amateur 24GHx converter is close enough to use.
> Copper water pipe that has been hammered into an oval can support TE01
> modes reliably enough if you need to suppress polarisation rotation.
>
> Andy
> www.g4jnt.com
>
One might want to look at the synthesizer, odd harmonics of the output 
might be better, depending on how the synthesis chain works. For 
instance, maybe you want to use an 7-8 Ghz synth and pick the 3rd 
harmonic. or even better, 5th harmonic of 4.76 GHz (which is well below 
the 5 GHz WiFi band, so there's lots of parts)