E
EWKehren@aol.com
Sat, Jan 5, 2013 12:18 AM
How about getting back to basics.
Is it a one off, if production how many and what are the specification
requirements? Otherwise on this list it can go on for a year.
Bert Kehren
In a message dated 1/4/2013 6:11:14 P.M. Eastern Standard Time,
wlfuqu00@uky.edu writes:
At 07:51 PM 1/4/2013 +0000, you wrote:
My question is about the phase noise of the final 16MHz signal. Do
crystal filters "clean up" the signal. It seems that after several
16MHz crystals in series the output should look a lot like an XO.
For offsets out to 100 Hz or so, using a crystal filter will cause
the signal to have the same flicker noise that an oscillator built
with that crystal would have. Thus don't try to use some junky
clock crystals to make a crystal filter as described in numerous
ham radio articles about receiver IF filters. If you have a
residual phase noise measurement system like the Agilent E5505A
and a very low flicker noise source, you can actually measure your
filter crystals. Of course, the crystal time base in the source
has to be better than the crystals you are measuring. You also
have to avoid overdriving the crystal. This will require a low
noise buffer amplifier to bring the signal back up to a high
level.
Now after considering all that, crystal clean up filters don't
sound like such a great idea unless you have no alternative.
Rick Karlquist N6RK
Flicker noise (1/f ) noise would be introduced by an amplifier and not
by the filter. I am only suggesting ways to multiply the frequency.
You could use LC filters or a crystal filter. Using 3 doublers would
do the job just as well. Naturally if you are concerned about flicker noise
you could simply make the 2 MHz signal higher in amplitude before selecting
the 8th harmonic.
I was not saying your going to clean up a good crystal oscillator with a
crystal filter. I though you were talking about generating 16MHz from 10MHz
in a clean way. Using a microcontroller or even most synthesizers
techniques would make
it even worse.
The PTS synthesizers have fairly good phase noise when they use
frequency multiplication,
division, mixing, comb generation and filtering on the most part to
achieve
low phase noise.
The later models use a DDS at the lower frequency levels but do have
greater phase noise
close to the carrier. In fact in the SGA unit the reference input goes
thru a transistor ( to distort it)
and then into a series 10MHz crystal filter so that it can accept either a
5 or 10 MHz input.
The crystal also helps filter out any birdies that may be on the
reference signal.
The filter should be fairly high Q since it has 47 Ohm drive impedance and
100 Ohm load impedance.
73
Bill wa4lav
time-nuts mailing list -- time-nuts@febo.com
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and follow the instructions there.
How about getting back to basics.
Is it a one off, if production how many and what are the specification
requirements? Otherwise on this list it can go on for a year.
Bert Kehren
In a message dated 1/4/2013 6:11:14 P.M. Eastern Standard Time,
wlfuqu00@uky.edu writes:
At 07:51 PM 1/4/2013 +0000, you wrote:
>My question is about the phase noise of the final 16MHz signal. Do
> > crystal filters "clean up" the signal. It seems that after several
> > 16MHz crystals in series the output should look a lot like an XO.
> >
>
>For offsets out to 100 Hz or so, using a crystal filter will cause
>the signal to have the same flicker noise that an oscillator built
>with that crystal would have. Thus don't try to use some junky
>clock crystals to make a crystal filter as described in numerous
>ham radio articles about receiver IF filters. If you have a
>residual phase noise measurement system like the Agilent E5505A
>and a very low flicker noise source, you can actually measure your
>filter crystals. Of course, the crystal time base in the source
>has to be better than the crystals you are measuring. You also
>have to avoid overdriving the crystal. This will require a low
>noise buffer amplifier to bring the signal back up to a high
>level.
>
>Now after considering all that, crystal clean up filters don't
>sound like such a great idea unless you have no alternative.
>
>Rick Karlquist N6RK
Flicker noise (1/f ) noise would be introduced by an amplifier and not
by the filter. I am only suggesting ways to multiply the frequency.
You could use LC filters or a crystal filter. Using 3 doublers would
do the job just as well. Naturally if you are concerned about flicker noise
you could simply make the 2 MHz signal higher in amplitude before selecting
the 8th harmonic.
I was not saying your going to clean up a good crystal oscillator with a
crystal filter. I though you were talking about generating 16MHz from 10MHz
in a clean way. Using a microcontroller or even most synthesizers
techniques would make
it even worse.
The PTS synthesizers have fairly good phase noise when they use
frequency multiplication,
division, mixing, comb generation and filtering on the most part to
achieve
low phase noise.
The later models use a DDS at the lower frequency levels but do have
greater phase noise
close to the carrier. In fact in the SGA unit the reference input goes
thru a transistor ( to distort it)
and then into a series 10MHz crystal filter so that it can accept either a
5 or 10 MHz input.
The crystal also helps filter out any birdies that may be on the
reference signal.
The filter should be fairly high Q since it has 47 Ohm drive impedance and
100 Ohm load impedance.
73
Bill wa4lav
_______________________________________________
time-nuts mailing list -- time-nuts@febo.com
To unsubscribe, go to
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and follow the instructions there.
BC
Bob Camp
Sat, Jan 5, 2013 12:48 AM
Hi
As I recall the spec was:
- Cheap
- no phase slips on the 16 MHz relative to 10 MHz
- Cheap
Bob
On Jan 4, 2013, at 7:18 PM, EWKehren@aol.com wrote:
How about getting back to basics.
Is it a one off, if production how many and what are the specification
requirements? Otherwise on this list it can go on for a year.
Bert Kehren
In a message dated 1/4/2013 6:11:14 P.M. Eastern Standard Time,
wlfuqu00@uky.edu writes:
At 07:51 PM 1/4/2013 +0000, you wrote:
My question is about the phase noise of the final 16MHz signal. Do
crystal filters "clean up" the signal. It seems that after several
16MHz crystals in series the output should look a lot like an XO.
For offsets out to 100 Hz or so, using a crystal filter will cause
the signal to have the same flicker noise that an oscillator built
with that crystal would have. Thus don't try to use some junky
clock crystals to make a crystal filter as described in numerous
ham radio articles about receiver IF filters. If you have a
residual phase noise measurement system like the Agilent E5505A
and a very low flicker noise source, you can actually measure your
filter crystals. Of course, the crystal time base in the source
has to be better than the crystals you are measuring. You also
have to avoid overdriving the crystal. This will require a low
noise buffer amplifier to bring the signal back up to a high
level.
Now after considering all that, crystal clean up filters don't
sound like such a great idea unless you have no alternative.
Rick Karlquist N6RK
Flicker noise (1/f ) noise would be introduced by an amplifier and not
by the filter. I am only suggesting ways to multiply the frequency.
You could use LC filters or a crystal filter. Using 3 doublers would
do the job just as well. Naturally if you are concerned about flicker noise
you could simply make the 2 MHz signal higher in amplitude before selecting
the 8th harmonic.
I was not saying your going to clean up a good crystal oscillator with a
crystal filter. I though you were talking about generating 16MHz from 10MHz
in a clean way. Using a microcontroller or even most synthesizers
techniques would make
it even worse.
The PTS synthesizers have fairly good phase noise when they use
frequency multiplication,
division, mixing, comb generation and filtering on the most part to
achieve
low phase noise.
The later models use a DDS at the lower frequency levels but do have
greater phase noise
close to the carrier. In fact in the SGA unit the reference input goes
thru a transistor ( to distort it)
and then into a series 10MHz crystal filter so that it can accept either a
5 or 10 MHz input.
The crystal also helps filter out any birdies that may be on the
reference signal.
The filter should be fairly high Q since it has 47 Ohm drive impedance and
100 Ohm load impedance.
73
Bill wa4lav
time-nuts mailing list -- time-nuts@febo.com
To unsubscribe, go to
https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
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and follow the instructions there.
Hi
As I recall the spec was:
1) Cheap
2) no phase slips on the 16 MHz relative to 10 MHz
3) Cheap
Bob
On Jan 4, 2013, at 7:18 PM, EWKehren@aol.com wrote:
> How about getting back to basics.
> Is it a one off, if production how many and what are the specification
> requirements? Otherwise on this list it can go on for a year.
> Bert Kehren
>
>
> In a message dated 1/4/2013 6:11:14 P.M. Eastern Standard Time,
> wlfuqu00@uky.edu writes:
>
> At 07:51 PM 1/4/2013 +0000, you wrote:
>> My question is about the phase noise of the final 16MHz signal. Do
>>> crystal filters "clean up" the signal. It seems that after several
>>> 16MHz crystals in series the output should look a lot like an XO.
>>>
>>
>> For offsets out to 100 Hz or so, using a crystal filter will cause
>> the signal to have the same flicker noise that an oscillator built
>> with that crystal would have. Thus don't try to use some junky
>> clock crystals to make a crystal filter as described in numerous
>> ham radio articles about receiver IF filters. If you have a
>> residual phase noise measurement system like the Agilent E5505A
>> and a very low flicker noise source, you can actually measure your
>> filter crystals. Of course, the crystal time base in the source
>> has to be better than the crystals you are measuring. You also
>> have to avoid overdriving the crystal. This will require a low
>> noise buffer amplifier to bring the signal back up to a high
>> level.
>>
>> Now after considering all that, crystal clean up filters don't
>> sound like such a great idea unless you have no alternative.
>>
>> Rick Karlquist N6RK
> Flicker noise (1/f ) noise would be introduced by an amplifier and not
> by the filter. I am only suggesting ways to multiply the frequency.
> You could use LC filters or a crystal filter. Using 3 doublers would
> do the job just as well. Naturally if you are concerned about flicker noise
> you could simply make the 2 MHz signal higher in amplitude before selecting
> the 8th harmonic.
> I was not saying your going to clean up a good crystal oscillator with a
> crystal filter. I though you were talking about generating 16MHz from 10MHz
> in a clean way. Using a microcontroller or even most synthesizers
> techniques would make
> it even worse.
> The PTS synthesizers have fairly good phase noise when they use
> frequency multiplication,
> division, mixing, comb generation and filtering on the most part to
> achieve
> low phase noise.
> The later models use a DDS at the lower frequency levels but do have
> greater phase noise
> close to the carrier. In fact in the SGA unit the reference input goes
> thru a transistor ( to distort it)
> and then into a series 10MHz crystal filter so that it can accept either a
> 5 or 10 MHz input.
> The crystal also helps filter out any birdies that may be on the
> reference signal.
> The filter should be fairly high Q since it has 47 Ohm drive impedance and
> 100 Ohm load impedance.
> 73
> Bill wa4lav
>
>
>
> _______________________________________________
> time-nuts mailing list -- time-nuts@febo.com
> To unsubscribe, go to
> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
> and follow the instructions there.
>
> _______________________________________________
> time-nuts mailing list -- time-nuts@febo.com
> To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
> and follow the instructions there.
PS
paul swed
Sat, Jan 5, 2013 12:49 AM
I think the thread branched and as I recall started something like this.
Someone needed a "Simple" 16 Mhz for a uproc made from a 10 Mhz source.
Two reasonable answers were given.
Injection locked oscillator
Typical div and mult/filter.
A third and kind of interesting for me a Ti chip soic digital pll.
Then the thread went a whole bunch of directions.
Wonder if who ever needed an answer got the answer?
Regards
Paul
WB8TSL
On Fri, Jan 4, 2013 at 7:18 PM, EWKehren@aol.com wrote:
How about getting back to basics.
Is it a one off, if production how many and what are the specification
requirements? Otherwise on this list it can go on for a year.
Bert Kehren
In a message dated 1/4/2013 6:11:14 P.M. Eastern Standard Time,
wlfuqu00@uky.edu writes:
At 07:51 PM 1/4/2013 +0000, you wrote:
My question is about the phase noise of the final 16MHz signal. Do
crystal filters "clean up" the signal. It seems that after several
16MHz crystals in series the output should look a lot like an XO.
For offsets out to 100 Hz or so, using a crystal filter will cause
the signal to have the same flicker noise that an oscillator built
with that crystal would have. Thus don't try to use some junky
clock crystals to make a crystal filter as described in numerous
ham radio articles about receiver IF filters. If you have a
residual phase noise measurement system like the Agilent E5505A
and a very low flicker noise source, you can actually measure your
filter crystals. Of course, the crystal time base in the source
has to be better than the crystals you are measuring. You also
have to avoid overdriving the crystal. This will require a low
noise buffer amplifier to bring the signal back up to a high
level.
Now after considering all that, crystal clean up filters don't
sound like such a great idea unless you have no alternative.
Rick Karlquist N6RK
Flicker noise (1/f ) noise would be introduced by an amplifier and not
by the filter. I am only suggesting ways to multiply the frequency.
You could use LC filters or a crystal filter. Using 3 doublers would
do the job just as well. Naturally if you are concerned about flicker
noise
you could simply make the 2 MHz signal higher in amplitude before
selecting
the 8th harmonic.
I was not saying your going to clean up a good crystal oscillator with a
crystal filter. I though you were talking about generating 16MHz from
10MHz
in a clean way. Using a microcontroller or even most synthesizers
techniques would make
it even worse.
The PTS synthesizers have fairly good phase noise when they use
frequency multiplication,
division, mixing, comb generation and filtering on the most part to
achieve
low phase noise.
The later models use a DDS at the lower frequency levels but do have
greater phase noise
close to the carrier. In fact in the SGA unit the reference input goes
thru a transistor ( to distort it)
and then into a series 10MHz crystal filter so that it can accept either a
5 or 10 MHz input.
The crystal also helps filter out any birdies that may be on the
reference signal.
The filter should be fairly high Q since it has 47 Ohm drive impedance and
100 Ohm load impedance.
73
Bill wa4lav
time-nuts mailing list -- time-nuts@febo.com
To unsubscribe, go to
https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
and follow the instructions there.
time-nuts mailing list -- time-nuts@febo.com
To unsubscribe, go to
https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
and follow the instructions there.
I think the thread branched and as I recall started something like this.
Someone needed a "Simple" 16 Mhz for a uproc made from a 10 Mhz source.
Two reasonable answers were given.
Injection locked oscillator
Typical div and mult/filter.
A third and kind of interesting for me a Ti chip soic digital pll.
Then the thread went a whole bunch of directions.
Wonder if who ever needed an answer got the answer?
Regards
Paul
WB8TSL
On Fri, Jan 4, 2013 at 7:18 PM, <EWKehren@aol.com> wrote:
> How about getting back to basics.
> Is it a one off, if production how many and what are the specification
> requirements? Otherwise on this list it can go on for a year.
> Bert Kehren
>
>
> In a message dated 1/4/2013 6:11:14 P.M. Eastern Standard Time,
> wlfuqu00@uky.edu writes:
>
> At 07:51 PM 1/4/2013 +0000, you wrote:
> >My question is about the phase noise of the final 16MHz signal. Do
> > > crystal filters "clean up" the signal. It seems that after several
> > > 16MHz crystals in series the output should look a lot like an XO.
> > >
> >
> >For offsets out to 100 Hz or so, using a crystal filter will cause
> >the signal to have the same flicker noise that an oscillator built
> >with that crystal would have. Thus don't try to use some junky
> >clock crystals to make a crystal filter as described in numerous
> >ham radio articles about receiver IF filters. If you have a
> >residual phase noise measurement system like the Agilent E5505A
> >and a very low flicker noise source, you can actually measure your
> >filter crystals. Of course, the crystal time base in the source
> >has to be better than the crystals you are measuring. You also
> >have to avoid overdriving the crystal. This will require a low
> >noise buffer amplifier to bring the signal back up to a high
> >level.
> >
> >Now after considering all that, crystal clean up filters don't
> >sound like such a great idea unless you have no alternative.
> >
> >Rick Karlquist N6RK
> Flicker noise (1/f ) noise would be introduced by an amplifier and not
> by the filter. I am only suggesting ways to multiply the frequency.
> You could use LC filters or a crystal filter. Using 3 doublers would
> do the job just as well. Naturally if you are concerned about flicker
> noise
> you could simply make the 2 MHz signal higher in amplitude before
> selecting
> the 8th harmonic.
> I was not saying your going to clean up a good crystal oscillator with a
> crystal filter. I though you were talking about generating 16MHz from
> 10MHz
> in a clean way. Using a microcontroller or even most synthesizers
> techniques would make
> it even worse.
> The PTS synthesizers have fairly good phase noise when they use
> frequency multiplication,
> division, mixing, comb generation and filtering on the most part to
> achieve
> low phase noise.
> The later models use a DDS at the lower frequency levels but do have
> greater phase noise
> close to the carrier. In fact in the SGA unit the reference input goes
> thru a transistor ( to distort it)
> and then into a series 10MHz crystal filter so that it can accept either a
> 5 or 10 MHz input.
> The crystal also helps filter out any birdies that may be on the
> reference signal.
> The filter should be fairly high Q since it has 47 Ohm drive impedance and
> 100 Ohm load impedance.
> 73
> Bill wa4lav
>
>
>
> _______________________________________________
> time-nuts mailing list -- time-nuts@febo.com
> To unsubscribe, go to
> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
> and follow the instructions there.
>
> _______________________________________________
> time-nuts mailing list -- time-nuts@febo.com
> To unsubscribe, go to
> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
> and follow the instructions there.
>
BC
Bob Camp
Sat, Jan 5, 2013 12:50 AM
HI
Ok, it's TimeNuts, we need numbers…
Say no phase slips is 0.1 UI on the 16 MHz. That would be a jitter number of 6.25 ns RMS.
Bob
On Jan 4, 2013, at 7:18 PM, EWKehren@aol.com wrote:
How about getting back to basics.
Is it a one off, if production how many and what are the specification
requirements? Otherwise on this list it can go on for a year.
Bert Kehren
In a message dated 1/4/2013 6:11:14 P.M. Eastern Standard Time,
wlfuqu00@uky.edu writes:
At 07:51 PM 1/4/2013 +0000, you wrote:
My question is about the phase noise of the final 16MHz signal. Do
crystal filters "clean up" the signal. It seems that after several
16MHz crystals in series the output should look a lot like an XO.
For offsets out to 100 Hz or so, using a crystal filter will cause
the signal to have the same flicker noise that an oscillator built
with that crystal would have. Thus don't try to use some junky
clock crystals to make a crystal filter as described in numerous
ham radio articles about receiver IF filters. If you have a
residual phase noise measurement system like the Agilent E5505A
and a very low flicker noise source, you can actually measure your
filter crystals. Of course, the crystal time base in the source
has to be better than the crystals you are measuring. You also
have to avoid overdriving the crystal. This will require a low
noise buffer amplifier to bring the signal back up to a high
level.
Now after considering all that, crystal clean up filters don't
sound like such a great idea unless you have no alternative.
Rick Karlquist N6RK
Flicker noise (1/f ) noise would be introduced by an amplifier and not
by the filter. I am only suggesting ways to multiply the frequency.
You could use LC filters or a crystal filter. Using 3 doublers would
do the job just as well. Naturally if you are concerned about flicker noise
you could simply make the 2 MHz signal higher in amplitude before selecting
the 8th harmonic.
I was not saying your going to clean up a good crystal oscillator with a
crystal filter. I though you were talking about generating 16MHz from 10MHz
in a clean way. Using a microcontroller or even most synthesizers
techniques would make
it even worse.
The PTS synthesizers have fairly good phase noise when they use
frequency multiplication,
division, mixing, comb generation and filtering on the most part to
achieve
low phase noise.
The later models use a DDS at the lower frequency levels but do have
greater phase noise
close to the carrier. In fact in the SGA unit the reference input goes
thru a transistor ( to distort it)
and then into a series 10MHz crystal filter so that it can accept either a
5 or 10 MHz input.
The crystal also helps filter out any birdies that may be on the
reference signal.
The filter should be fairly high Q since it has 47 Ohm drive impedance and
100 Ohm load impedance.
73
Bill wa4lav
time-nuts mailing list -- time-nuts@febo.com
To unsubscribe, go to
https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
and follow the instructions there.
time-nuts mailing list -- time-nuts@febo.com
To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
and follow the instructions there.
HI
Ok, it's TimeNuts, we need numbers…
Say no phase slips is 0.1 UI on the 16 MHz. That would be a jitter number of 6.25 ns RMS.
Bob
On Jan 4, 2013, at 7:18 PM, EWKehren@aol.com wrote:
> How about getting back to basics.
> Is it a one off, if production how many and what are the specification
> requirements? Otherwise on this list it can go on for a year.
> Bert Kehren
>
>
> In a message dated 1/4/2013 6:11:14 P.M. Eastern Standard Time,
> wlfuqu00@uky.edu writes:
>
> At 07:51 PM 1/4/2013 +0000, you wrote:
>> My question is about the phase noise of the final 16MHz signal. Do
>>> crystal filters "clean up" the signal. It seems that after several
>>> 16MHz crystals in series the output should look a lot like an XO.
>>>
>>
>> For offsets out to 100 Hz or so, using a crystal filter will cause
>> the signal to have the same flicker noise that an oscillator built
>> with that crystal would have. Thus don't try to use some junky
>> clock crystals to make a crystal filter as described in numerous
>> ham radio articles about receiver IF filters. If you have a
>> residual phase noise measurement system like the Agilent E5505A
>> and a very low flicker noise source, you can actually measure your
>> filter crystals. Of course, the crystal time base in the source
>> has to be better than the crystals you are measuring. You also
>> have to avoid overdriving the crystal. This will require a low
>> noise buffer amplifier to bring the signal back up to a high
>> level.
>>
>> Now after considering all that, crystal clean up filters don't
>> sound like such a great idea unless you have no alternative.
>>
>> Rick Karlquist N6RK
> Flicker noise (1/f ) noise would be introduced by an amplifier and not
> by the filter. I am only suggesting ways to multiply the frequency.
> You could use LC filters or a crystal filter. Using 3 doublers would
> do the job just as well. Naturally if you are concerned about flicker noise
> you could simply make the 2 MHz signal higher in amplitude before selecting
> the 8th harmonic.
> I was not saying your going to clean up a good crystal oscillator with a
> crystal filter. I though you were talking about generating 16MHz from 10MHz
> in a clean way. Using a microcontroller or even most synthesizers
> techniques would make
> it even worse.
> The PTS synthesizers have fairly good phase noise when they use
> frequency multiplication,
> division, mixing, comb generation and filtering on the most part to
> achieve
> low phase noise.
> The later models use a DDS at the lower frequency levels but do have
> greater phase noise
> close to the carrier. In fact in the SGA unit the reference input goes
> thru a transistor ( to distort it)
> and then into a series 10MHz crystal filter so that it can accept either a
> 5 or 10 MHz input.
> The crystal also helps filter out any birdies that may be on the
> reference signal.
> The filter should be fairly high Q since it has 47 Ohm drive impedance and
> 100 Ohm load impedance.
> 73
> Bill wa4lav
>
>
>
> _______________________________________________
> time-nuts mailing list -- time-nuts@febo.com
> To unsubscribe, go to
> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
> and follow the instructions there.
>
> _______________________________________________
> time-nuts mailing list -- time-nuts@febo.com
> To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
> and follow the instructions there.
R
Rex
Sat, Jan 5, 2013 10:57 AM
On 1/4/2013 4:48 PM, Bob Camp wrote:
Hi
As I recall the spec was:
- Cheap
- no phase slips on the 16 MHz relative to 10 MHz
- Cheap
Bob
GAK!
Here is the original from TVB
What's the simplest way to generate 16 MHz from 10 MHz? This will be for clocking a microcontroller at 16 MHz given 10 MHz (Cs/Rb/GPSDO). Low price and low parts count is a goal; jitter is not a concern but absolute long-term phase coherence is a must.
The ICS525 (as in TAPR Clock-Block) is a good candidate but I was wondering if there's something cheaper, less functional, and maybe not SSOP. Any suggestions?
Thanks,
/tvb
This cluster f**k of responses losing track of the original but blathering on for days is so typical of the group lately.
On 1/4/2013 4:48 PM, Bob Camp wrote:
> Hi
>
> As I recall the spec was:
>
> 1) Cheap
> 2) no phase slips on the 16 MHz relative to 10 MHz
> 3) Cheap
>
> Bob
>
GAK!
Here is the original from TVB
What's the simplest way to generate 16 MHz from 10 MHz? This will be for clocking a microcontroller at 16 MHz given 10 MHz (Cs/Rb/GPSDO). Low price and low parts count is a goal; jitter is not a concern but absolute long-term phase coherence is a must.
The ICS525 (as in TAPR Clock-Block) is a good candidate but I was wondering if there's something cheaper, less functional, and maybe not SSOP. Any suggestions?
Thanks,
/tvb
This cluster f**k of responses losing track of the original but blathering on for days is so typical of the group lately.
EB
Ed Breya
Mon, Jan 7, 2013 10:30 PM
I'm kind of late to the party on this one, and don't want to reopen and
send it off on a tangent. I agree with the injection-lock method, but
just want to suggest that since most uPs and uCs have their own CMOS
oscillator built in, the simplest solution would be to just use that as
intended, with a cheap 16 MHz crystal or ceramic resonator, and
injection lock it to a low impedance version of the 10 MHz clock, via an
RCD network. It may need a variable cap to tweak the resonator to the
lock frequency.
Ed
I'm kind of late to the party on this one, and don't want to reopen and
send it off on a tangent. I agree with the injection-lock method, but
just want to suggest that since most uPs and uCs have their own CMOS
oscillator built in, the simplest solution would be to just use that as
intended, with a cheap 16 MHz crystal or ceramic resonator, and
injection lock it to a low impedance version of the 10 MHz clock, via an
RCD network. It may need a variable cap to tweak the resonator to the
lock frequency.
Ed
PS
paul swed
Tue, Jan 8, 2013 1:22 AM
Ed you are late to the dance. But do offer an additional piece of the
puzzle.
RCD I will guess is a RC differentiator. And your suggestion does get rid
of a separate oscillator. It wasn't my post. But would guess you just jam
the diff pulse into the osc amp in that the xtal feeds?
Regards
Paul
WB8TSL
On Mon, Jan 7, 2013 at 5:30 PM, Ed Breya eb@telight.com wrote:
I'm kind of late to the party on this one, and don't want to reopen and
send it off on a tangent. I agree with the injection-lock method, but just
want to suggest that since most uPs and uCs have their own CMOS oscillator
built in, the simplest solution would be to just use that as intended, with
a cheap 16 MHz crystal or ceramic resonator, and injection lock it to a low
impedance version of the 10 MHz clock, via an RCD network. It may need a
variable cap to tweak the resonator to the lock frequency.
Ed
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Ed you are late to the dance. But do offer an additional piece of the
puzzle.
RCD I will guess is a RC differentiator. And your suggestion does get rid
of a separate oscillator. It wasn't my post. But would guess you just jam
the diff pulse into the osc amp in that the xtal feeds?
Regards
Paul
WB8TSL
On Mon, Jan 7, 2013 at 5:30 PM, Ed Breya <eb@telight.com> wrote:
> I'm kind of late to the party on this one, and don't want to reopen and
> send it off on a tangent. I agree with the injection-lock method, but just
> want to suggest that since most uPs and uCs have their own CMOS oscillator
> built in, the simplest solution would be to just use that as intended, with
> a cheap 16 MHz crystal or ceramic resonator, and injection lock it to a low
> impedance version of the 10 MHz clock, via an RCD network. It may need a
> variable cap to tweak the resonator to the lock frequency.
>
> Ed
>
> ______________________________**_________________
> time-nuts mailing list -- time-nuts@febo.com
> To unsubscribe, go to https://www.febo.com/cgi-bin/**
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> and follow the instructions there.
>
EB
Ed Breya
Tue, Jan 8, 2013 2:27 AM
Actually, I was referring to an RC and Diode network in anticipation of
the possible need for more signal shaping flexibility, depending on the
signals and circuitry. The built-in oscillators are usually self-biased
CMOS inverters intended to go with crystals, and usually a couple of
small phase shift caps to ground. If you inject the right amount of
reference frequency at the input, the oscillator should sync up. Since
it's for a fixed frequency, the required lock range can be quite small -
it needs to be enough to compensate for drift in the resonator and
circuits - so the injection level probably can be small. Since the
oscillator input has plenty of gain, and the reference is likely a very
low impedance, I think a fairly high impedance passive coupling network
to link the two should suffice, without any extra active circuitry.
Ed
Actually, I was referring to an RC and Diode network in anticipation of
the possible need for more signal shaping flexibility, depending on the
signals and circuitry. The built-in oscillators are usually self-biased
CMOS inverters intended to go with crystals, and usually a couple of
small phase shift caps to ground. If you inject the right amount of
reference frequency at the input, the oscillator should sync up. Since
it's for a fixed frequency, the required lock range can be quite small -
it needs to be enough to compensate for drift in the resonator and
circuits - so the injection level probably can be small. Since the
oscillator input has plenty of gain, and the reference is likely a very
low impedance, I think a fairly high impedance passive coupling network
to link the two should suffice, without any extra active circuitry.
Ed
