LOL.Originally posted by carlosfm
The frequency I use?
Are you trying to receive my message by radio?
Sure. If you want to tell people you are generous, diyAudio will be there for you. In private you can change your mind, P-A will accept that. Elso, you were offered too, have you received your sample?Originally posted by peranders
I suggest that if Lars has changed his mind in some direction, please continue your communication in private.
Pedja
Elso,
Jocko clock circuit, the master clock of 11.288 MHz is as good as it can be. I use to be able to test clocks when I was at MCI at to stratum one levels, I do not have access that test equipment now. Oh it's a major improvement from the factory clock or the modification that I made.
In addition, the PS audio transport had a bunch of ACT logic parts, which caused a lot of noise. I changed that to 74ALS parts, much better now.
Since or squares?
I feel too lazy to search right now, so please forgive me if I
remember wrong. Jocko once posted a clock circuit on the
forum (don't know if that is the one you are talking about)
and while there were probably many things he did differently,
one thing was different already in the design philosophy.
Jockos clock was a sine-wave oscillator, not a square-wave
one, with the motivation that the overtones of a square wave
cause more problems than they solve by introducing a lot
of unnecessary HF noise. I don't have the experience with
DACs to judge which approach is best in practice, but at least
from the theoretical point of view Jockos approach seems to
make sense, and considering that Jocko is probably more of
a practitioner than a theoretician, my guess is it makes sense
in practice too.
I feel too lazy to search right now, so please forgive me if I
remember wrong. Jocko once posted a clock circuit on the
forum (don't know if that is the one you are talking about)
and while there were probably many things he did differently,
one thing was different already in the design philosophy.
Jockos clock was a sine-wave oscillator, not a square-wave
one, with the motivation that the overtones of a square wave
cause more problems than they solve by introducing a lot
of unnecessary HF noise. I don't have the experience with
DACs to judge which approach is best in practice, but at least
from the theoretical point of view Jockos approach seems to
make sense, and considering that Jocko is probably more of
a practitioner than a theoretician, my guess is it makes sense
in practice too.
jewilson said:
Elso,
Jocko clock circuit, the master clock of 11.288 MHz is as good as it can be. I use to be able to test clocks when I was at MCI at to stratum one levels, I do not have access that test equipment now. Oh it's a major improvement from the factory clock or the modification that I made.
In addition, the PS audio transport had a bunch of ACT logic parts, which caused a lot of noise. I changed that to 74ALS parts, much better now.
Thanks Jim, I will pester Jocko further off line........
My clock 8 is also as good as it can be........
Still did not try Jocko's clock supply
In the Lab we had stratum 1 cesium beam oscillator, GPS and LORAN-C clocking systems. When you wanted to test a clock, you sunk a HP clock synthesizer to one of the precision clock sources. You then can compare the jitter of your clock to that of clock of the HP. The HP allows you to tune the clock up or down, your
your external clock source signal. The UUT or clocks can be measured with a spectrum analyzer or a communication test set for accuracy. The error are normally measured in unit intervals see ITU G.171. There are bunch of different test sets that will tell you what the jitter and long-term drift is and slips are.
This document may help
http://www.cirrus.com/cn/pubs/appNote/an12.pdf
http://www.reeve.com/Documents/Sync Testing R3.pdf
your external clock source signal. The UUT or clocks can be measured with a spectrum analyzer or a communication test set for accuracy. The error are normally measured in unit intervals see ITU G.171. There are bunch of different test sets that will tell you what the jitter and long-term drift is and slips are.
This document may help
http://www.cirrus.com/cn/pubs/appNote/an12.pdf
http://www.reeve.com/Documents/Sync Testing R3.pdf
Yes, i have all those tools, but this did not prevend me from going to university trying to study. So i have not enough time to do sensible productive real world work and get a little money for it but have to do a lot of stupid akademic mess and am poor this time as result. Maybe it was a mistake . Better should go to the workshop.
I will not build something i do not understand like that Lars clock. I need to understand how and why and how to proove if it works right first.
I will not build something i do not understand like that Lars clock. I need to understand how and why and how to proove if it works right first.
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