[time-nuts] Re: 10 MHz TCXO periodically jumping 20 mHz up and down

[Andy Talbot]

At that time the synth was set to one frequency and the code went into
sleep , so any buffering resistors etc would have served no purpose.
The TCXO really was hopping over four frequencies in a PN way at intervals
of a little under one second per hop.

Andy
www.g4jnt.com



On Sat, 19 Feb 2022 at 20:46, glen english LIST <glenlist at cortexrf.com.au>
wrote:

> Andy, do you have the PIC and the synthesiser chip data control lines
> well buffered/isolated (nice big resistors etc on the data lines ?)
>
> Any sort of current you inject into the synth chip will find its way
> onto the output....
>
> On 19/02/2022 7:55 pm, Andy Talbot wrote:
> > A while back I purchased a low cost TCXO which I then used as the
> reference
> > for a synthesizer generating 10GHz.  Listening to the output on an SSB
> > radio, the tone was hopping in a random fashion over four frequencies,
> > spaced a few tens of Hz apart.   This was surreal!  I had, at that time,
> > been building Multifrequency Shift Keyed data sources ( for WSJT modes)
> by
> > programming synths directly, but this wasn't the case here.   Yet the
> > hopping tones sounded just like the modulation I woul
> _______________________________________________
> time-nuts mailing list -- time-nuts at lists.febo.com -- To unsubscribe send
> an email to time-nuts-leave at lists.febo.com
> To unsubscribe, go to and follow the instructions there.
>