Perhaps then this trick should be used with an ovenized oscillator of
lesser quality, since it sounds like the E1938A will work just fine if
stuck in the snow.
Snow is probably a stable temperature.
--
These are my opinions, not necessarily my employer's. I hate spam.
Hal Murray wrote:
Perhaps then this trick should be used with an ovenized oscillator of
lesser quality, since it sounds like the E1938A will work just fine if
stuck in the snow.
Snow is probably a stable temperature.
There's just that minor problem with the snow melted by the
, December 14, 2007 4:03 AM
Subject: Re: [time-nuts] need recomendation for a portable 10mhz reference
oscilator
Perhaps then this trick should be used with an ovenized oscillator of
lesser quality, since it sounds like the E1938A will work just fine if
stuck in the snow.
Snow is probably
There's just that minor problem with the snow melted by the E1938A.
That was mostly in jest, but on the other hand, if you want a stable
temperature snow can be a useful tool.
It often comes in large quantities. A E1938A isn't going to melt many cubic
meters per day.
Snow is often a very
At 11:38 AM -0800 12/11/07, Eric Fort wrote:
I'm looking for a fairly basic, relatively simple 10 Mhz PORTABLE
reference (probably quartz based) with enough stability over a period
of a week of outdoor temp extremes to keep a 47Ghz transmitter locked
within 100hz while mountaintop contesting.
In a message dated 12/13/2007 09:58:04 Pacific Standard Time,
[EMAIL PROTECTED] writes:
oscillator. You could slip it into a pocket you would sew in your
long johns in the armpit or groin area. That should keep it
toasty-warm at all times.
Hi David,
that HP puck runs it's crystal at
[EMAIL PROTECTED] wrote:
Hi David,
that HP puck runs it's crystal at over 100 Degrees C, and the enclosure
temperature of a typical OCXO gets to above 60C in still air.
They also have Tantalum caps, and anyone who has seen a fiery Tantalum cap
explosion knows these things can be
From: Bruce Griffiths [EMAIL PROTECTED]
Subject: Re: [time-nuts] need recomendation for a portable 10mhz reference
oscilator
Date: Fri, 14 Dec 2007 11:22:52 +1300
Message-ID: [EMAIL PROTECTED]
The E1938A oven has exceptionally high thermal gain so variations in the
OCXO frequency due
David Forbes wrote:
Bruce,
Perhaps then this trick should be used with an ovenized oscillator of lesser
quality,
since it sounds like the E1938A will work just fine if stuck in the snow.
Not that I have one on hand to test, anyways.
David
Putting an OCXO in your pocket may cause
Magnus Danielson wrote:
Why would it be very hard? For his purpose it should easy enought to measure
the frequency shift which he would allow, and achieving the necessary shift
in
temperature to get the ball-park aspect should not be too hard to acheive
in a
home enviorment and a
- Original Message -
From: Bruce Griffiths [EMAIL PROTECTED]
To: Discussion of precise time and frequency measurement
time-nuts@febo.com
Sent: Thursday, December 13, 2007 6:08 PM
Subject: Re: [time-nuts] need recomendation for a portable 10mhz reference
oscilator
Magnus Danielson
From: bg [EMAIL PROTECTED]
Subject: Re: [time-nuts] need recomendation for a portable 10mhz reference
oscilator
Date: Wed, 12 Dec 2007 06:58:15 +0100
Message-ID: [EMAIL PROTECTED]
On Tue, 2007-12-11 at 18:38 -0500, John Ackermann N8UR wrote:
To get decent (for some definition of decent
In a message dated 12/11/2007 22:00:37 Pacific Standard Time,
[EMAIL PROTECTED] writes:
I am surprised surveying mode is needed anymore. In a SA environment it
makes sense, but for me its hard to understand with the current accuracy
given by the GPS system.
--
Björn
Hi Bjoern,
I'm looking for a fairly basic, relatively simple 10 Mhz PORTABLE
reference (probably quartz based) with enough stability over a period
of a week of outdoor temp extremes to keep a 47Ghz transmitter locked
within 100hz while mountaintop contesting. Suggestions are
appreciated. something that is
In a message dated 12/11/2007 11:41:02 Pacific Standard Time,
[EMAIL PROTECTED] writes:
I'm looking for a fairly basic, relatively simple 10 Mhz PORTABLE
reference (probably quartz based) with enough stability over a period
of a week of outdoor temp extremes to keep a 47Ghz transmitter
A good (and well-aged) double-oven OCXO with aging compensation should
be able to provide that type of performance. The problem is: how
much physical movement will the unit experience? What are the
temperature extremes that are expected, and how fast does the
ambient move between the temp
From: Eric Fort [EMAIL PROTECTED]
Subject: [time-nuts] need recomendation for a portable 10mhz reference oscilator
Date: Tue, 11 Dec 2007 11:38:40 -0800
Message-ID: [EMAIL PROTECTED]
Eric,
I'm looking for a fairly basic, relatively simple 10 Mhz PORTABLE
reference (probably quartz based
Hal Murray wrote:
I'm picturing an open hill top at night with clear skies so there would be
lots of radiation cooling. Of course, with an open hill top, GPS recption
would be easy.
As great as GPSDO are, the problem with using them in a portable
environment is the time it takes to do a
Hal Murray wrote:
A good (and well-aged) double-oven OCXO with aging compensation should
be able to provide that type of performance. The problem is: how
much physical movement will the unit experience? What are the
temperature extremes that are expected, and how fast does the
ambient move
John Ackermann N8UR wrote:
Hal Murray wrote:
I'm picturing an open hill top at night with clear skies so there would be
lots of radiation cooling. Of course, with an open hill top, GPS recption
would be easy.
As great as GPSDO are, the problem with using them in a portable
As great as GPSDO are, the problem with using them in a portable
environment is the time it takes to do a survey and then get to final
lock; mountain-toppers may not be in one place long enough.
What if you use a navigation GPS unit rather than a timing unit?
How long does a survey take (in
that helps/
Alan G3NYK
- Original Message -
From: John Ackermann N8UR [EMAIL PROTECTED]
To: Discussion of precise time and frequency measurement
time-nuts@febo.com
Sent: Tuesday, December 11, 2007 8:56 PM
Subject: Re: [time-nuts] need recomendation for a portable 10mhz reference
oscilator
Hal Murray said the following on 12/11/2007 05:57 PM:
As great as GPSDO are, the problem with using them in a portable
environment is the time it takes to do a survey and then get to final
lock; mountain-toppers may not be in one place long enough.
What if you use a navigation GPS unit
Hello Eric,
I picked up a few ISOTEMP VCXOs from Pyro Joe on ebay. 12VDC operation
Currently using one as a 10 MHz reference for my AD6IW PLL osc for the
LO on my DB6NT 10 G2.
For the control voltage, I use a multi turn pot and cal at home, before
the contest weekend.
I am tickled with the
On Dec 11, 2007 6:38 PM, John Ackermann N8UR [EMAIL PROTECTED] wrote:
How long does a survey take (in good conditions) and what sort of time
constant would you want to use with a navigation box?
It depends on the receiver, but usually it's a few hours to a full day.
Of course, if you use
In a message dated 12/11/2007 13:14:14 Pacific Standard Time,
[EMAIL PROTECTED] writes:
Why not lock it to a GPS timing receiver output when its at home, and
allow the controller to learn the aging and tempco characteristics etc
of the oscillator being disciplined and use this information
Eric Fort wrote:
I'm looking for a fairly basic, relatively simple 10 Mhz PORTABLE
reference (probably quartz based) with enough stability over a period
of a week of outdoor temp extremes to keep a 47Ghz transmitter locked
within 100hz while mountaintop contesting. Suggestions are
On Tue, 2007-12-11 at 18:38 -0500, John Ackermann N8UR wrote:
To get decent (for some definition of decent) timing, you need to
operate the receiver in 0-D mode, telling it where it is and letting
it solve just for time. I haven't done the experiments myself but I
believe that the time
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