Re: [time-nuts] Counter Internal Oscillator Importance with External Reference?

CERN have flagged another potential issue with the 53230A in that every so often seemingly randomly communications go hawire. Bruce > > On 10 May 2017 at 04:46 "Richard (Rick) Karlquist" > wrote: > > On 5/9/2017 12:05 AM, Poul-Henning Kamp wrote: > > > >

Re: [time-nuts] Counter Internal Oscillator Importance with External Reference?

On 5/9/2017 12:05 AM, Poul-Henning Kamp wrote: I'm sure that modern counters like 53230 are better at this than The 53230 oven oscillator option in an inferior oscillator to the 10811, by an order of magnitude. So in this case, modern != better. Rick

Re: [time-nuts] Counter Internal Oscillator Importance with External Reference?

In message <54ee7bdd-0a49-cc49-540d-2812e70dd...@rubidium.dyndns.org>, Magnus Danielson writes: >Wither it is proper side bands or other systematic noise, it is bad >indeed, [...] It's more subtle than that, it can be things like thresholds in the counters trigger being sensitive to

Re: [time-nuts] Counter Internal Oscillator Importance with External Reference?

Hi Poul-Henning, On 05/09/2017 02:39 PM, Poul-Henning Kamp wrote: In message <60c74d75-41e5-7112-d8b6-721664b89...@rubidium.dyndns.org>, Magnus Danielson writes: Indeed. On the other hand some measurements is hard not to do that way. One should think about how isolation is created

Re: [time-nuts] Counter Internal Oscillator Importance with External Reference?

Hi, In HP5370A/B you mux sources. In SR620 there is a lockup PLL, as far as I remember. Cheers, Magnus On 05/09/2017 01:11 PM, Bob kb8tq wrote: Hi If you grab the schematic of pretty much any of these counters, you find a fairly common approach. Somewhere inside is a VHF oscillator. The

Re: [time-nuts] Counter Internal Oscillator Importance with External Reference?

In message <60c74d75-41e5-7112-d8b6-721664b89...@rubidium.dyndns.org>, Magnus Danielson writes: >Indeed. On the other hand some measurements is hard not to do that way. >One should think about how isolation is created if needed, and this >includes AC and DC, common mode and

Re: [time-nuts] Counter Internal Oscillator Importance with External Reference?

Hi If you grab the schematic of pretty much any of these counters, you find a fairly common approach. Somewhere inside is a VHF oscillator. The internal TCXO, OCXO, or Rb acts as a phase lock source for that VHF oscillator. Typical PLL bandwidths are pretty low (10’s of Hz). When you put in

Re: [time-nuts] Counter Internal Oscillator Importance with External Reference?

Hi, On 05/09/2017 09:05 AM, Poul-Henning Kamp wrote: In message , Magnus Danielson writes: Also, there is a reason that you can buy different internal oscillators, this is one of them. For labs with their frequency

Re: [time-nuts] Counter Internal Oscillator Importance with External Reference?

In message , Magnus Danielson writes: >Also, there is a reason that you can buy different internal oscillators, >this is one of them. For labs with their frequency distribution there is >no need to waste money on stand-alone

Re: [time-nuts] Counter Internal Oscillator Importance with External Reference?

Hi Tom! On 05/09/2017 03:02 AM, Tom Knox wrote: Hi All; How important is the standard, medium, or high stability reference in counters like the 53230A, or FCA3120 when locked to an ultra low phase noise external reference? Particularly when making measurements and adjustments on other ultra

[time-nuts] Counter Internal Oscillator Importance with External Reference?

Hi All; How important is the standard, medium, or high stability reference in counters like the 53230A, or FCA3120 when locked to an ultra low phase noise external reference? Particularly when making measurements and adjustments on other ultra high performance references? I know Agilent sold