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'[OT]: What Test Gear to measure xtal frequency to '
2002\08\12@061245 by Peter Crowcroft

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We are using a 12.000MHz crystal in a timer circuit. It has 2 x 33pF load
capacitors and the xtal is under the IC socket so the tracks to the uC are
0.15" only.

We want to measure the osc frequency to within 1Hz so we can adjust the
load cap in one leg. Can someone tell us what test gear we need to be able
to do this?

regards,

Peter Crowcroft
            DIY Electronics (HK) Ltd
      PO Box 88458, Sham Shui Po, Hong Kong
Factory: voice 852-2304 2250    Fax: 852-2729 1400
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2002\08\12@070932 by veronica.merryfield

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I would make a small LC tank centered at 12Mhz across a scope input with an
arial close to the xtal and use a scope output into a frequency meter
although a good scope would measure the freq as well.

You could write a program to help you - either using the timer/counter if
you have one of just a loop that outputs a pulse based on NOPs and a jump -
this would allow you to measure, but this will divide the 1Hz resolution
you are looking for unless you use a big divide and an equally big count
time.

Just a few thoughts.

Veronica, somewhere in Cambridgeshire, UK
"The best things in life aren't things"

Original Message:
-----------------
From: Peter Crowcroft peterspamKILLspamKITSRUS.COM
Date: Mon, 12 Aug 2002 18:12:05 +0800
To: .....PICLISTKILLspamspam.....MITVMA.MIT.EDU
Subject: [OT]: What Test Gear to measure xtal frequency to 1Hz


We are using a 12.000MHz crystal in a timer circuit. It has 2 x 33pF load
capacitors and the xtal is under the IC socket so the tracks to the uC are
0.15" only.

We want to measure the osc frequency to within 1Hz so we can adjust the
load cap in one leg. Can someone tell us what test gear we need to be able
to do this?

regards,

Peter Crowcroft
            DIY Electronics (HK) Ltd
      PO Box 88458, Sham Shui Po, Hong Kong
Factory: voice 852-2304 2250    Fax: 852-2729 1400
         M/F, 97 Fuk Wa Street, Sham Shui Po
Home: voice 852-2720 0255          Mobile: 6273 2049
Web:  http://www.kitsrus.com        Email: EraseMEpeterspam_OUTspamTakeThisOuTkitsrus.com
      Yahoo Messenger  'peter5999'  with webcam
      Pay with Paypal:  peterspamspam_OUTkitsrus.com
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2002\08\12@075324 by Morgan Olsson

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Hej @spam@veronica.merryfieldKILLspamspamtesco.net. Tack för ditt meddelande 11:59 2002-08-12 enligt nedan:
>I would make a small LC tank centered at 12Mhz across a scope input with an
>arial close to the xtal

I suggest a current pickup held to supply trace would pick up stronger signal, plus not interfere at all with xtal resonance.

Problem is finding a good 12 000 000 Hz reference.
good Xtal and caps & osc, helt at controlled constant temperature
...but what to calibrate to?

/Morgan

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2002\08\12@081410 by mike

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Remember that by connecting anything to the xtal pins you will change
its frequency due to capacitance. If you're after the sort of accuracy
you mention, it will be very difficult to acheive it with any sort of
direct connection.
A MUCH MUCH better way to do it is to output a known frequency on a
PIC pin (perhaps in a special test/calibration mode), and measure
this. Most decent frequency counters ought to be able to do this to
the accuracy you require, but you should probably use one with a TXCO
or OCXO reference).


On Mon, 12 Aug 2002 18:12:05 +0800, you wrote:

{Quote hidden}

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2002\08\12@083318 by Mike Singer

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part 1 1026 bytes content-type:text/plain; (decoded 7bit)

Peter Crowcroft wrote:
.
.
> We are using a 12.000MHz crystal in a timer circuit. It has 2
> x 33pF load capacitors and the xtal is under the IC socket
> so the tracks to the uC are 0.15" only.
> We want to measure the osc frequency to within 1Hz so we can
> adjust the load cap in one leg. Can someone tell us what test
> gear we need to be able to do this?
.
.
Peter,
given your "12.000MHz crystal in a timer circuit" capable
of keeping 1Hz stably, you need nothing more, but
precision timer or clock, I think.
Count your timer ticks for a long enough precise time
period and you'll get  the osc frequency.
Then you may use one of your so precalibrated timer
circuits to fill periods of next your timers in order to
speed up measuring process.
You may get precise time signals from "radiostations of
precise time signals" for example.
Keeping 1Hz stably at 12.000MHz crystal is not a simple
task. look at Microchip's DS00588B.PDF.

Mike.


part 2 12638 bytes content-type:image/gif; (decode)


part 3 131 bytes
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2002\08\12@090837 by Spehro Pefhany

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At 06:12 PM 8/12/02 +0800, you wrote:
>We are using a 12.000MHz crystal in a timer circuit. It has 2 x 33pF load
>capacitors and the xtal is under the IC socket so the tracks to the uC are
>0.15" only.
>
>We want to measure the osc frequency to within 1Hz so we can adjust the
>load cap in one leg. Can someone tell us what test gear we need to be able
>to do this?

Suggest arranging an output of (e.g.) divide by 4, and then using a
reciprocal counter instrument to set the frequency.

Where did you pull that +/-1Hz spec out of? It's extremely tight
(0.08ppm), and the crystal frequency will drift more than that with
the slightest temperature change unless you are using a crystal oven.

Best regards,

Spehro Pefhany --"it's the network..."            "The Journey is the reward"
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2002\08\12@095553 by Jim

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I have used a high-gain pre-amp in front of a
counter before and simply contacted the crystal
can and picked up enough signal to cause the
counter to count. Alternatively one can often
simply come close to one of the osc pins (w/o
touching) and also get enough signal wwith an
appropriate pre-amp before the counter.


The other technique would involve an HF (some call them
"shortwave") receiver tuned in and around 12 MHz while
listening using a short piece of wire connected to the
antenna input laying in the vicinity of the osc circuit.

The procedure involves tuning for about a 1 KHz tone
using the BFO (or Upper Sideband) and then zero-beating
an external signal generator against this 1 KHz tone
produced by the 12 MHz osc.

Using this technique I have been able to measure the
frequency of stations off-the-air to the limits of the
generator I was using (which was capble of 1 Hz steps).

RF Jim

{Original Message removed}

2002\08\12@101320 by Jim

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> You may get precise time signals from "radiostations
> of precise time signals" for example.

Here in the states there are receivers that receive a signal
of 60 KHz directly that are usd to keep/correct time.

Of course, GPS is another obvious choice for either correct
time or time correction (using 1 Hz time "pulses" from receiver).

As Mike pointed out, keeping simple un-ovenized, free-running
crystal oscillaters "on-frequency" is a considerable design task
itself. (Each and every crystal exhibits slightly different
characteristics over temperature and time that MUST be offset
in a variety of ways - not to mention requirements for periodic
calibration at say, yearly intervals, that are meant correct for
component and crystal aging.)

RF Jim


{Original Message removed}

2002\08\12@120039 by Alan B. Pearce

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>I would make a small LC tank centered at 12Mhz across a scope input with an
>arial close to the xtal and use a scope output into a frequency meter
>although a good scope would measure the freq as well.

I would doubt the ability to read to 1Hz in 12MHz on a scope, unless it has
a really good digital readout, but the accuracy of the crystal in the scope
timebase is probably about the same as you are trying to measure.

A good frequency counter will probably trigger from a pickup coil such as
mentioned, but then it will need a proper ovened timebase which is regularly
referenced to a standard to get anything meaningful of the accuracy you are
looking for. Remember that you will really need a standard good for 0.1Hz in
12MHz to make your efforts worth while.

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2002\08\12@121423 by Spehro Pefhany

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At 04:59 PM 8/12/02 +0100, you wrote:

>A good frequency counter will probably trigger from a pickup coil such as
>mentioned, but then it will need a proper ovened timebase which is regularly
>referenced to a standard to get anything meaningful of the accuracy you are
>looking for. Remember that you will really need a standard good for 0.1Hz in
>12MHz to make your efforts worth while.

Anything that gets close enough to the crystal to read the signal will
probably affect the frequency by more than 0.08ppm. If the capacitor
affects the frequency by, say, 20ppm/pF, then changes in stray capacitance
of more than 4 FEMTOFARADS (0.004pF) will affect the frequency more than 1Hz.

NS patented a neat way of calibrating LED watches way back, they used the
mux frequency of the display as a non-contact way of transmitting the
frequency externally. You could do that with the "power on" LED in a product,
just run it at 50% duty cycle at 4MHz and use a PIN photodiode to pick up
the signal. Visible LEDs typically switch in around 100ns, so that should
not be a problem.

Best regards,

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2002\08\12@130720 by Harold M Hallikainen

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       Also, remember that setting a 12 MHz oscillator to within 1 Hz means it
isn't going to stay there. That's 0.1 ppm. Really good crystal
oscillators (with temperature compensation or ovens) can maybe do 1 ppm
or so.

Harold


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2002\08\12@132658 by Peter L. Peres

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On Mon, 12 Aug 2002, Morgan Olsson wrote:

>Hej RemoveMEveronica.merryfieldspamTakeThisOuTtesco.net. Tack för ditt meddelande 11:59 2002-08-12 enligt nedan:
>>I would make a small LC tank centered at 12Mhz across a scope input with an
>>arial close to the xtal
>
>I suggest a current pickup held to supply trace would pick up stronger signal, plus not interfere at all with xtal resonance.
>
>Problem is finding a good 12 000 000 Hz reference.
>good Xtal and caps & osc, helt at controlled constant temperature
>...but what to calibrate to?

Frequency standard, 10e6. 12e6 = 10e6 + 10e6/5. Or calibrate a counter to
10e6 then use it to measure 12e6. He probably does not need 1 part in
12e6. That's about 0.3 sec/month in a timer. That kind of timer would use
a TCXO at the very least. It is equivalent to 0.08 ppm. My heterodyne
method described in another message allows easy tuning to +/-2Hz at high
productivity. 2Hz at 12e6 is 1/6e6 or 0.16 ppm or 0.6 sec/month (much less
than 1 sec/month in any case).

Peter

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2002\08\12@132852 by Peter L. Peres

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On Mon, 12 Aug 2002, Spehro Pefhany wrote:

>Where did you pull that +/-1Hz spec out of? It's extremely tight
>(0.08ppm), and the crystal frequency will drift more than that with
>the slightest temperature change unless you are using a crystal oven.

And even then...

Peter

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2002\08\13@143711 by Peter L. Peres

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On Mon, 12 Aug 2002, Spehro Pefhany wrote:

>NS patented a neat way of calibrating LED watches way back, they used the
>mux frequency of the display as a non-contact way of transmitting the
>frequency externally. You could do that with the "power on" LED in a product,
>just run it at 50% duty cycle at 4MHz and use a PIN photodiode to pick up
>the signal. Visible LEDs typically switch in around 100ns, so that should
>not be a problem.

Neat, however good luck passing emissions certification with a device
that has a 4MHz 30mW radiator on it (in H field at least). Maybe one could
put it into jig mode using a jumper and output a slower clock (a few kHz).

Peter

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2002\08\14@135609 by Mike Singer

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Harold M Hallikainen wrote:
> Also, remember that setting a 12 MHz oscillator to
> within 1 Hz means it isn't going to stay there.
> That's 0.1 ppm. Really good crystal oscillators
> (with temperature compensation or ovens) can maybe
> do 1 ppm or so.

Yes, from Electronicstalk.com:

"The FTS501AH OCXO offers a frequency stability of
+/-250ppb over the standard temperature range of 0 to 70C"

(ppb = 1000 ppm ?)

Mike.


News article from Electronicstalk.com
____________________________________________________________

OVEN-COMPENSATED CRYSTAL HOLDS FORM FOR TELECOMMS
____________________________________________________________

Date: 9 August 2002
News from: Fox Electronics
Product: FTS501AH
http://www.electronicstalk.com/news/fox/fox107.html

The FTS501AH OCXO (oven-compensated crystal oscillator) meets
stratum level accuracy requirements for telecommunications
applications, making it ideal for use in basestations, telecomms
switching, GPS and LAN/WAN applications as well as in test and
satellite equipment. This is the latest product developed and
manufactured at Fox's Customer Technology Centre (CTC), based at
the company's headquarters in Fort Myers, FL. The FTS501AH OCXO
offers a frequency stability of +/-250ppb over the standard
temperature range of 0 to 70C and an overall accuracy of
+/-4.6ppm for all conditions over 10 years. Frequency range of
the new OCXO is 10 to 40MHz. Supply voltage is 5.0V, with 3.3V
available, and control voltage is 0.5 to 5.0V. Storage
temperature range is -40 to 85. In addition to the 14-pin DIP
configuration, Fox's new oscillators are offered in a variety of
different packaging and stabilities, based on customer
requirements. The OCXOs are also available in CMOS and sinewave
versions. Pricing for the new FTS501AH OCXOs begins at $68 each
in quantities of 1000. Delivery is 8 weeks ARO, depending on
frequency.

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2002\08\14@143854 by Jim

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  "oven-compensated crystal oscillator"

1) Do you know what this could do to your power budget?

2) How about required warm-up times after power-up before
  seeing those quoted accuracy specs?

 RF Jim

{Original Message removed}

2002\08\14@144525 by Dave Tweed

face
flavicon
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Mike Singer <RemoveMEmikeEraseMEspamEraseMEPOLUOSTROV.NET> wrote:
> Harold M Hallikainen wrote:
> > Also, remember that setting a 12 MHz oscillator to
> > within 1 Hz means it isn't going to stay there.
> > That's 0.1 ppm. Really good crystal oscillators
> > (with temperature compensation or ovens) can maybe
> > do 1 ppm or so.
>
> Yes, from Electronicstalk.com:
>
> "The FTS501AH OCXO offers a frequency stability of
> > +/-250ppb over the standard temperature range of 0 to 70C"

I just saw a similar announcement in EETimes for single- and double-OCXO
oscillators for telecom use (Stratum 2 and 3) that have short-term holdover
accuracy of 10 ppb and 1 ppb over 24 hours. I forget who the manufacturer
is.

> (ppb = 1000 ppm ?)

No, 1000 ppb = 1 ppm.

-- Dave Tweed

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2002\08\14@144933 by Peter L. Peres

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part 1 283 bytes content-type:TEXT/PLAIN; CHARSET=US-ASCII
On Mon, 12 Aug 2002, Mike Singer wrote:

> Keeping 1Hz stably at 12.000MHz crystal is not a simple
>task. look at Microchip's DS00588B.PDF.

DS00588B.PDF is not known to any search engine (including not Microchip's
own). Can you please give the title or proper name ?

Peter


part 2 12638 bytes content-type:IMAGE/GIF; NAME="FREQUENCY vs. TEMPERATURE CURVE FOR A-T CUT CRYSTAL.gif" (decode)

part 3 105 bytes
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2002\08\14@145357 by Geo

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On 14 Aug 2002, at 11:43, Dave Tweed wrote:

> I just saw a similar announcement in EETimes for single- and double-OCXO
> oscillators for telecom use (Stratum 2 and 3) that have short-term holdover
> accuracy of 10 ppb and 1 ppb over 24 hours. I forget who the manufacturer is.
Noticed that in another mag...
7x5mm
3.3v 2.5-4mA
+-0.32ppm over 24hr
+-4.6ppm 20 years
-20 +70C
C-MAC
http://www.cmac.com/mt

George Smith

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2002\08\14@152240 by Peter L. Peres

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On Wed, 14 Aug 2002, Mike Singer wrote:

>Harold M Hallikainen wrote:
>> Also, remember that setting a 12 MHz oscillator to
>> within 1 Hz means it isn't going to stay there.
>> That's 0.1 ppm. Really good crystal oscillators
>> (with temperature compensation or ovens) can maybe
>> do 1 ppm or so.
>
>Yes, from Electronicstalk.com:
>
>"The FTS501AH OCXO offers a frequency stability of
>+/-250ppb over the standard temperature range of 0 to 70C"
>
>(ppb = 1000 ppm ?)

Yes, billion = 1e9

The only small problem is price. Fox TCXOs were around $40 when I last
checked and the spec was worse than 0.25ppm.

Peter

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2002\08\14@152824 by Peter L. Peres

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On Wed, 14 Aug 2002, Jim wrote:

>   "oven-compensated crystal oscillator"
>
>1) Do you know what this could do to your power budget?
>
>2) How about required warm-up times after power-up before
>   seeing those quoted accuracy specs?

I am surprised to hear this. Normally you put a TCXO in an oven and
provide the possibility to switch the oven, no ?

Peter

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2002\08\14@165856 by Mike Singer

picon face
Peter L. Peres wrote:
> DS00588B.PDF is not known to any search engine
> (including not Microchip's own). Can you please
> give the title or proper name ?

AN588

PICmicroT Microcontroller Oscillator Design Guide

Author: Kim Peck
Consultant

---------------

Mike.

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2002\08\14@174342 by Harold M Hallikainen

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On Wed, 14 Aug 2002 19:07:08 +0300 Mike Singer <KILLspammikespamBeGonespamPOLUOSTROV.NET>
writes:
> Harold M Hallikainen wrote:
> > Also, remember that setting a 12 MHz oscillator to
> > within 1 Hz means it isn't going to stay there.
> > That's 0.1 ppm. Really good crystal oscillators
> > (with temperature compensation or ovens) can maybe
> > do 1 ppm or so.
>
> Yes, from Electronicstalk.com:
>
> "The FTS501AH OCXO offers a frequency stability of
> +/-250ppb over the standard temperature range of 0 to 70C"
>
> (ppb = 1000 ppm ?)
>

       Probably, unless you're in England where a billion is a million million
(10^12), whereas in the US, it's a thousand million (10^9).
       Glad we speak the same language???

Harold


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2002\08\14@174357 by Harold M Hallikainen

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On Wed, 14 Aug 2002 13:14:51 -0500 Jim <@spam@jvpoll@spam@spamspam_OUTDALLAS.NET> writes:
>    "oven-compensated crystal oscillator"
>
> 1) Do you know what this could do to your power budget?
>
> 2) How about required warm-up times after power-up before
>    seeing those quoted accuracy specs?
>
>   RF Jim

       I haven't done much RF work recently. Back when I was in broadcast,
where we're allowed about 20 ppm (20 Hz for AM, 2 kHz for FM), the
crystal was often mounted in a glass envelope with a vacuum. They seemed
to have no trouble staying on frequency. An AM would drift a few Hz
months to month.
       The 950 MHz studio to transmitter link we used had the transmit crystal
for the PLL reference in an oven. This worked great until the thermostat
got stuck. The main transmitter dropped off the air because the STL
transmitter frequency went far enough from the receiver frequency that we
lost the 110 kHz control subcarrier.
       I remember years ago seeing a PTC thermistor that clipped on a crystal
can. It would self heat to hold the crystal at temperature. I think it
was from murata. Of course, it'd be best to hold the oscillator and the
crystal at a constant temperature.
       The original TXCOs were really a challenge since you had to use analog
circuitry to match the tempco of the crystal and other circuitry. Now, I
expect they use an eeprom to hold a table of trim values to bring it back
on frequency for each temperature in the range.

Harold



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2002\08\14@174758 by info

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       Probably, unless you're in England where a billion is a million
million (10^12), whereas in the US, it's a thousand million (10^9).
       Glad we speak the same language???

Harold



You sure that's not 1000 million and 100 billion, respectively
Scott



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2002\08\14@180253 by mike

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On Wed, 14 Aug 2002 22:24:11 +0300, you wrote:

>On Wed, 14 Aug 2002, Mike Singer wrote:
>
>>Harold M Hallikainen wrote:
>>> Also, remember that setting a 12 MHz oscillator to
>>> within 1 Hz means it isn't going to stay there.
>>> That's 0.1 ppm. Really good crystal oscillators
>>> (with temperature compensation or ovens) can maybe
>>> do 1 ppm or so.
>>
>>Yes, from Electronicstalk.com:
>>
>>"The FTS501AH OCXO offers a frequency stability of
>>+/-250ppb over the standard temperature range of 0 to 70C"
>>
>>(ppb = 1000 ppm ?)
>
>Yes, billion = 1e9
>
>The only small problem is price. Fox TCXOs were around $40 when I last
>checked and the spec was worse than 0.25ppm.
Almost every cellphone contains a TXCO, therefore they must be
gettable for a lot less than $40.....

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2002\08\14@192423 by Jim

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You are now introducing a new term: TCXO.

"Temp comp xtal osc" - a device compensated
for changes in temperature as opposed to
a device that resides *within* an oven which
assures it's stability (which was the discussion
at hand) ...

RF Jim




{Original Message removed}

2002\08\14@202849 by Jim

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.
>  "The original TXCOs were really a challenge since
>   you had to use analog circuitry to match the
>   tempco of the crystal and other circuitry"
.
Motorola mastered this technique late in their
"Motrac" series ("Motorola Transistor Research Line"
of 2-way FM commercial radios) - with the last ovenized
crystals used about 1965. All the newer product utilized
a technique in the form of little modules known as
"channel elements" versus discrete "crystals" placed
in small ovens.

To build these solid-state "channel elements" it was a
matter of characterizing each xtal and determining it's
"curve" (see Peter's postings) and selecting the
correct valued compensation cap to placed in series
with thermistors (with various characteristics) along
with other ceramic caps that had also known variation
over temperature ...

I've uesd the PTC thermistor myself - to keep a 10.24 MHz
ref osc on frequency over temperature in an automotive
install on a VHF Engineering 2-Meter synthesizer that gave
"frequency agility" to a 1965 "E"-series Motorola Motrac
in the mid-70's (predating the compact, Japanese synthesized
radios by a few years!) ...

RF Jim



{Original Message removed}

2002\08\14@214707 by dbengtson

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On Wed, 14 Aug 2002 23:02:11 +0100, you wrote:

{Quote hidden}

They are if you buy several million a month. Cellphone TCXO's also are
only good to about +/- 2.5 ppm, and then they sync to the inbound
channel to get closer than that.


Dave

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2002\08\14@221006 by Jim

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(To the list this time!)

  "Almost every cellphone contains a TXCO"

This solution is trivial anymore since the
advent of the microprocessor (MEASURE the
ambient temperature, do a look-up in a table
BASED on that particular crystal's "curve"
(see Peter's postings) and feed a DC voltage
to a vari-cap diode incorporated in the
crystal oscillator's circuit!) - OR -

- anymore it's a real easy matter to 'slave' the
cell phone's frequency from transmissions coming
on the "downlink" side (from the base station).

Heck - the Ericsson RBS882 BS (base station) gear
was synchonized to the 1.544 MBit/Sec "T-span"
coming from the MTSO (mobile telephone switching
office) where all the 'clocking' on those spans
is derived from very accurate sources (a higher
tier point from somewhere else in the network)!

RF (and telco) Jim



{Original Message removed}

2002\08\15@153625 by Peter L. Peres

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On Wed, 14 Aug 2002, Jim wrote:

>You are now introducing a new term: TCXO.
>
>"Temp comp xtal osc" - a device compensated
>for changes in temperature as opposed to
>a device that resides *within* an oven which
>assures it's stability (which was the discussion
>at hand) ...

Yes but combining the two is better than either alone ... and I've used
such devices (analog built ones).

Peter

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2002\08\15@153652 by Peter L. Peres

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On Wed, 14 Aug 2002, Jim wrote:

>advent of the microprocessor (MEASURE the
>ambient temperature, do a look-up in a table
>BASED on that particular crystal's "curve"
                                    ^^^^^
Why do you like that word so much ? ;-) I'd say you speak some other
languages too ... (what do you call the bloody freq/temp line, a graph ?
Are you greek or something ? ;-)

Peter

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2002\08\15@162724 by Mike Singer

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Peter L. Peres wrote:
>
> >advent of the microprocessor (MEASURE the
> >ambient temperature, do a look-up in a table
> >BASED on that particular crystal's "curve"
>                                      ^^^^^
> Why do you like that word so much ? ;-) I'd
> say you speak some other languages too ...
> (what do you call the bloody freq/temp line,
> a graph ?
> Are you greek or something ? ;-)
>
> Peter
>

Peter, in proportional font you underscored
"curve" word, in Arial font "particular" word
is underscored.
"Curve" is usual word for a function graph.
What are you worried about here?

Mike.

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2002\08\15@164644 by Jim

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What?

Have you NEVER heard of a "curve" tracer?

(Methinks you need to get out more ...)

RF Jim

{Original Message removed}

2002\08\15@235725 by Bill & Pookie

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When you all think of graphs and semiconductors
when the word "curve" is mentioned, meknows you
all need to get out more.

Pookie

{Original Message removed}

2002\08\16@045400 by Russell McMahon

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> > > Are you greek or something ? ;-)

Yes indeed - every person on this list, without exception, is :-)


                       RM

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2002\08\16@090218 by Dale Botkin

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On Fri, 16 Aug 2002, Russell McMahon wrote:

> > > > Are you greek or something ? ;-)
>
> Yes indeed - every person on this list, without exception, is :-)

Russell, he said Greek, not GEEK...  8-)

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2002\08\16@090630 by Jim

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> meknows you all need to get out more.

How so Bill?

I was away for several years doing 'other
things' before getting back into the field
of electronics at the circuit design level.

Get back to me when you've done a stint in
a semiconductor manufactures's "front end"
and worked with SPAs (Semiconductor Parameter
Analyzers - the direct descendant to the
venerable "Curve Tracer" line produced by
Tektronix) ... I have also personally owned
and used one of the early Tektronix "Vacuum
Tube" curve tracers (meant to sweep and
characterize vacuum tubes) as well as their
first semi-conductror curve tracer ...

RF Jim


{Original Message removed}

2002\08\16@103607 by Mike Mansheim

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On Fri, 16 Aug 2002, Russell McMahon wrote:

>>>> Are you greek or something ? ;-)

>> Yes indeed - every person on this list, without exception, is :-)

> Russell, he said Greek, not GEEK...  8-)

I assumed it was a shot at sloppy semantics:
logically, "[anything] or something" covers everybody
(and what better group for knowing the power of "or" in a conditional!)
although it is more fun to get the geek reference in...

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2002\08\16@204131 by Russell McMahon

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> > meknows you all need to get out more.
>
> How so Bill?

No - that was Pookie who said that.


       RM

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2002\08\16@213544 by Jim

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Okay ...

How so Pookie?

RF Jim


----- Original Message -----
From: "Russell McMahon" <RemoveMEapptechspamspamBeGonePARADISE.NET.NZ>
To: <spamBeGonePICLIST@spam@spamspam_OUTMITVMA.MIT.EDU>
Sent: Friday, August 16, 2002 7:37 PM
Subject: Re: [OT]: What Test Gear to measure xtal frequency to 1Hz


{Quote hidden}

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2002\08\17@164747 by Peter L. Peres

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On Fri, 16 Aug 2002, Russell McMahon wrote:

>> > > Are you greek or something ? ;-)
>
>Yes indeed - every person on this list, without exception, is :-)

With some of the recent threads, I think I'll believe you on that. The
delete button is wearing out.

Peter

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2002\08\17@165409 by Peter L. Peres

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On Thu, 15 Aug 2002, Jim wrote:

>What?
>
>Have you NEVER heard of a "curve" tracer?
>
>(Methinks you need to get out more ...)

And "trace" some "curves" ? No thanks.

Peter

PS: curve means hookers in a certain other language. But this is an
english language mailing list <duck>

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2002\08\17@165439 by Peter L. Peres

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On Fri, 16 Aug 2002, Mike Mansheim wrote:

>On Fri, 16 Aug 2002, Russell McMahon wrote:
>
>>>>> Are you greek or something ? ;-)
>
>>> Yes indeed - every person on this list, without exception, is :-)
>
>> Russell, he said Greek, not GEEK...  8-)
>
>I assumed it was a shot at sloppy semantics:
>logically, "[anything] or something" covers everybody
>(and what better group for knowing the power of "or" in a conditional!)
>although it is more fun to get the geek reference in...

Sloppy semantics is, when someone addresses an email that start with 'John
...' to a mailing list with >1800 members and g*d know how many Johns on
it, not the replay to that email, imho.

Peter

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2002\08\19@174507 by Mike Mansheim

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Peter L. Peres wrote:
> Sloppy semantics is, when someone addresses an email that start with
> 'John...' to a mailing list with >1800 members and g*d know how many
> Johns on it, not the replay to that email, imho.

I agree that would be annoying - did I do that?  I've looked back at
the message I posted, and I'm not sure what you're referring to.

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2002\08\19@183139 by Russell McMahon

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> > Sloppy semantics is, when someone addresses an email that start with
> > 'John...' to a mailing list with >1800 members and g*d know how many
> > Johns on it, not the replay to that email, imho.

Peter (  :-) ) , when I see that I generally take it as meaning that they
are making a specific (sometimes) pointed) comment to the original poster in
a conversation that is known to have a wider audience. I think it is often
more a nuance than a slop.


       Russell

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2002\08\21@161818 by Peter L. Peres

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On Mon, 19 Aug 2002, Mike Mansheim wrote:

>Peter L. Peres wrote:
>> Sloppy semantics is, when someone addresses an email that start with
>> 'John...' to a mailing list with >1800 members and g*d know how many
>> Johns on it, not the replay to that email, imho.
>
>I agree that would be annoying - did I do that?  I've looked back at
>the message I posted, and I'm not sure what you're referring to.

No, I was speaking in general.

Peter

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