[time-nuts] An (unknown?) nasty feature of the DDS principle for time nuts applications
dk4xp at arcor.de
Tue Jan 25 21:26:36 UTC 2011
Am 25.01.2011 15:35, schrieb Ulrich Bangert:
> see page 8.6ff of the service manual to see that the HP3325 is not DDS based
> but uses a "Fractional N Synthesizer scheme" which is something completely
> different and is not prone to the described effects.
Yes, it's f-N, I must have stored that in the wrong winding of my brain...
Fortunately, I had no need to repair my 3325B upto now.
BTW, your effect has been described in detail in the article that
Bruce cited on jan7 in the NoStateOfTheArtCounter thread.
(seems not to work anymore, may be a typo of mine)
In the meantime, I have published my sin/cos table on
It should be easy to generate a version with BCD-coded phase input
to make a decimal-friendly DDS.
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