[time-nuts] Frequency counter questions

[Magnus Danielson]

Hi,

Many modern counters use this trick too, but much more gift-wrapped, in 
that they themselves shift their oscillator to measure the shift and 
hence figure out which overtone is being used and hence derive the 
correct frequency. With HP5245 etc you had to do a little work on your 
own for post-processing. The same basic trick is also fundamental to 
frequency comb measurement of optical frequencies.

Heterodyning remains one of several approaches to design high frequency 
counters.

Cheers,
Magnus


On 06/08/2017 02:35 PM, Scott McGrath wrote:
> The heterodyne trick has been done before the first
> 'Modern' frequency counter the HP 5245 used plug ins to extend its range to 18 Ghz by doing exactly that.   The plug in contained a tunable LO  mixer and indicator to show tuning lock
>
> These were a pain to use but they beat the 'frequency meters' by a mile
>
> Content by Scott
> Typos by Siri
>
>> On Apr 26, 2017, at 2:52 PM, al wolfe <alw.k9si at gmail.com> wrote:
>>
>> such
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