elektroda.net NewsGroups Forum Index - Electronics Design - XTL choice for 137Hz w/ CD4046
Goto page Previous 1, 2, 3, 4, 5
Jim Thompson
Guest
Guest
Fri Mar 12, 2010 12:20 am
On Fri, 12 Mar 2010 04:32:05 +0530, "pimpom" <pimpom_at_invalid.invalid>
wrote:
Quote:
Jim Thompson wrote:
On Fri, 12 Mar 2010 03:57:14 +0530, "pimpom"
pimpom_at_invalid.invalid
wrote:
Jim Thompson wrote:
I got married March 31 of my sophomore year at MIT.
This March 31 will be our 50th anniversary :-)
You married at 19? Me,
I turned _20_ on February 20, 1960, married on March 31, 1960
Heck, blame it on the fact that it was 4 AM when I typed that. I
had the distinct impression that we're now in the latter half of
the year (September was in my mind). That and the recentness of
your 70th birthday made me think that your anniversary comes
before your birthday!
Hey, you did say earlier that your birthday's Feb 29, didn't you?
Not Feb 20^. Can we attribute this to Skitt's Law?
.
On Fri, 12 Mar 2010 03:57:14 +0530, "pimpom"
pimpom_at_invalid.invalid
wrote:
Jim Thompson wrote:
I got married March 31 of my sophomore year at MIT.
This March 31 will be our 50th anniversary :-)
You married at 19? Me,
I turned _20_ on February 20, 1960, married on March 31, 1960
Heck, blame it on the fact that it was 4 AM when I typed that. I
had the distinct impression that we're now in the latter half of
the year (September was in my mind). That and the recentness of
your 70th birthday made me think that your anniversary comes
before your birthday!
Hey, you did say earlier that your birthday's Feb 29, didn't you?
Not Feb 20^. Can we attribute this to Skitt's Law?
.
Oooops! Typo, should be February _29_
We Thompson's are early prolificators, married at 20, first child born
when I was 22, second when I was almost 25, third when I was 30,
fourth when I was almost 33 ;-)
My parents married at 18, our own children have generally married
around 22-24, but the oldest son didn't marry until he was 30...
though he lived with a bunch of different women from an early age
...Jim Thompson
--
| James E.Thompson, CTO | mens |
| Analog Innovations, Inc. | et |
| Analog/Mixed-Signal ASIC's and Discrete Systems | manus |
| Phoenix, Arizona 85048 Skype: Contacts Only | |
| Voice:(480)460-2350 Fax: Available upon request | Brass Rat |
| E-mail Icon at http://www.analog-innovations.com | 1962 |
The only thing bipartisan in this country is hypocrisy
John Fields
Guest
Guest
Fri Mar 12, 2010 1:05 am
On Fri, 12 Mar 2010 08:17:26 +1000, David Eather <eather_at_tpg.com.au>
wrote:
Quote:
On 11/03/2010 8:16 PM, John Fields wrote:
On Thu, 11 Mar 2010 19:47:29 +1000, David Eather<eather_at_tpg.com.au
wrote:
On 11/03/2010 6:06 PM, Michael A. Terrell wrote:
Joerg wrote:
Don Lerner wrote:
If I use a CD 4060 to generate 137 Hz, given the divide down outputs
available, what frequency crystal should I use?
I am not aware of what crystals are commonly available, so my mind is
buckling trying to find a starting point.
Perhaps someone here is more familliar with this procedure and would
be so kind as to offer advice.
As the other posters said a uC is the better choice here. If it
absolutely has to be the 4060 the procedure goes like this:
Let Excel display a (2^x)*137 ladder of values, then see if any one
comes close to a standard crystal. The only one I could see would be the
former European chroma carrier frequency of 4.43MHz but you'd need
4.49MHz. Not easy to pull a crystal that far, it's more than a percent.
I don't think this is really going to work with a crystal unless you use
a uC, or the timer in there in particular.
This is a list of frequencies available from the Digikey website:
20.000 kHz
25.600 kHz
26.667 kHz
28.000 kHz
30.000 kHz
30.720 kHz
30.760 kHz
31.200 kHz
31.250 kHz
31.500 kHz
32.000 kHz
32.560 kHz
32.768 kHz
32.919 kHz
34.000 kHz
36.000 kHz
38.000 kHz
38.400 kHz
39.500 kHz
40.000 kHz
44.100 kHz
46.604 kHz
46.6084kHz
50.000 kHz
59.787 kHz
60.000 kHz
60.002 kHz
60.005 kHz
65.535 kHz
65.536 kHz
69.000 kHz
70.000 kHz
137 * 512 = 70.144k
an error of .2 percent. You should be able to trim that out
---
Since:
70000 Hz
---------- = 136.718 Hz
512
which is on the low side of 137Hz by a couple of thousand ppm, that's
unlikely.
JF
Any objections to 4.5Mhz divided by 2^15? ( gives 137.3291015625 0.23
percent error which is a bit high but can at least be partly corrected)
On Thu, 11 Mar 2010 19:47:29 +1000, David Eather<eather_at_tpg.com.au
wrote:
On 11/03/2010 6:06 PM, Michael A. Terrell wrote:
Joerg wrote:
Don Lerner wrote:
If I use a CD 4060 to generate 137 Hz, given the divide down outputs
available, what frequency crystal should I use?
I am not aware of what crystals are commonly available, so my mind is
buckling trying to find a starting point.
Perhaps someone here is more familliar with this procedure and would
be so kind as to offer advice.
As the other posters said a uC is the better choice here. If it
absolutely has to be the 4060 the procedure goes like this:
Let Excel display a (2^x)*137 ladder of values, then see if any one
comes close to a standard crystal. The only one I could see would be the
former European chroma carrier frequency of 4.43MHz but you'd need
4.49MHz. Not easy to pull a crystal that far, it's more than a percent.
I don't think this is really going to work with a crystal unless you use
a uC, or the timer in there in particular.
This is a list of frequencies available from the Digikey website:
20.000 kHz
25.600 kHz
26.667 kHz
28.000 kHz
30.000 kHz
30.720 kHz
30.760 kHz
31.200 kHz
31.250 kHz
31.500 kHz
32.000 kHz
32.560 kHz
32.768 kHz
32.919 kHz
34.000 kHz
36.000 kHz
38.000 kHz
38.400 kHz
39.500 kHz
40.000 kHz
44.100 kHz
46.604 kHz
46.6084kHz
50.000 kHz
59.787 kHz
60.000 kHz
60.002 kHz
60.005 kHz
65.535 kHz
65.536 kHz
69.000 kHz
70.000 kHz
137 * 512 = 70.144k
an error of .2 percent. You should be able to trim that out
---
Since:
70000 Hz
---------- = 136.718 Hz
512
which is on the low side of 137Hz by a couple of thousand ppm, that's
unlikely.
JF
Any objections to 4.5Mhz divided by 2^15? ( gives 137.3291015625 0.23
percent error which is a bit high but can at least be partly corrected)
---
Why go through all that grief when my way works with no correction
needed?
Or, if the OP needs 137Hz dead nuts, it's easy to do since the crystal
_and_ the divider error would only amount to a couple of hundred ppm or
so.
JF
elektroda.net NewsGroups Forum Index - Electronics Design - XTL choice for 137Hz w/ CD4046
