Hi
Your ADEV is (mostly) a plot of 1-2 ns resolution out over your sample range.
It’s not a “typical” three segment ADEV. It’s more likely that any departure
from a straight line is random rather than systematic. Yes I’ve spent a lot of
time looking at random plots that I was *sure* had
Hi,
I just bought a OSA 5240, did you still have the management software?
If yes can you provide me a copy?
Alex
___
time-nuts mailing list -- time-nuts@febo.com
To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
and follow
Hi Bob,
I take it that the 3 segment ADEV pretty much defines a GPSDO. So, is my plot
an indication that I'm riding the OCXO too hard to get the results I think I
should be getting? What I think I should be getting is a flat phase line. But
is a GPS receiver, even after applying
Hi Adrian,
Actually no. This ADEV is a plot of the sawtooth-corrected 1PPS signal from
the GPS receiver (LEA-6T) measured by the TIC in my GPSDO against the
output of its OCXO.
Bob
From: Adrian rfn...@arcor.de
To: Bob Stewart b...@evoria.net; Discussion of
Bob,
to me your ADEV plot looks pretty exactly like a measurement system
noise floor plot with its typical 10/decade shape.
I would assume that you connected the same signal to both counter
inputs, or, both sources have been phase locked.
Adrian
Bob Stewart schrieb:
Hi Bob,
I take it that
Hi,
I scored yesterday by a local seller some interesting GPSDO from Ocilloquartz.
The box is powering up, I have all output signals but I'm not sure if the sync
with the GPS is currently working because all front led are red.
I checked the GPS board and I have the 1PPS signal.
So I search
I'm sure this has been discussed to death before, but does anyone know
of a source of thermal fuses small enough to fit in the -hp- 10811? I
have found plenty of larger ones, none of which will fit and would
rather not just link it out.
Dan
___
Well, in that case you do measure a form of noise-floor rather than
measuring the OCXO performance, as OCXO performance is being corrected
out in the PPS position (and sawtooth-correction).
If you want to measure that OCXO performance, you need to do that
against an independent PPS.
Cheers,
I would just put in a piece of wire. They mostly only fail due to age. The wax
inside the fuse loosens up over time and then, eventualy, the two meatal strips
open up. Regards - Mike
Mike B. Feher, EOZ Inc.
89 Arnold Blvd.
Howell, NJ, 07731
732-886-5960 office
908-902-3831 cell
-Original
Hi Magnus,
I knew I was missing something! I'll warm up the Rb and test against that
again.
Thanks!
Bob
From: Magnus Danielson mag...@rubidium.dyndns.org
To: time-nuts@febo.com
Sent: Tuesday, September 2, 2014 3:27 PM
Subject: Re: [time-nuts] OCXO Phase
Bob,
Sounds like a plan!
Love to see your new data.
Cheers,
Magnus
On 09/02/2014 10:46 PM, Bob Stewart wrote:
Hi Magnus,
I knew I was missing something! I'll warm up the Rb and test against that
again.
Thanks!
Bob
From: Magnus Danielson
Dan,
On Ebay you'll find a seller called newdeparture2010 who has a good
range of fuses. He saved me a bucket load of money when I needed
replacement LittleFuses to repair my 11848A, before I learnt the right
way to apply the K23 to power supply measurements.
Cheers.
david
On 3/09/2014
Hi Bob,
Just realized I forgot to mention this...
As you have sawtooth data, one fun way to compare the GPS-OCXO is just
use the sawtooth data and then let TimeLab do the phase-unwrapping on
that. This will however not give good characterization of the stability
of the PPS output, which is
Dan,
I found the following thermal fuse: ESKA/Tamura model E3F
Check http://www.buerklin.com/ and type 30G4574 into the search field.
Model E3F is rated 115 Deg C with a normal operating temperature of up
to 85 Deg C.
See also
Hi
There are a lot of GPSDO ADEV plots out there. The T-Bolt has a lot of plots
run on it, there are others.
Ideally the plot should start out looking like an OCXO:
1) Left hand side rising as you go left. Rate of rise 1/Tau.
2) Left hand side intersecting a flat region somewhere in the 0.1 to
On 9/2/2014 12:23 PM, Dan Rae wrote:
I'm sure this has been discussed to death before, but does anyone know
of a source of thermal fuses small enough to fit in the -hp- 10811? I
have found plenty of larger ones, none of which will fit and would
rather not just link it out.
Dan
I believe a thermal cut-out is a device which interrupts the circuit
when a prescribed temperature is reached or exceeded (in some cases by
heating from an increase in current through a conductor), but which
re-connects the circuit once the temperature has dropped below the
cut-out
Hi
The gotcha of using a telecom Rb is that it (probably) has a worse ADEV than a
good GPSDO out to somewhere in the 100 second range. It also (probably) isn’t
going to do much good in the 20,000 seconds range either.
Much easier to just build two or three GPSDO’s…. at least then you can
Hi Bob,
Thanks for the review. I thought I knew a good deal of that, and promptly
forgot it in the heat of battle.
Here's a plot of about 8,000 samples vs my trusty FE-5680A. The blue is the
OCXO output vs the Rb as measured on my 5335A w/10811 clock. The red is the
OCXO vs corrected 1PPS
This type of cutout fuse can never re-connect. It is a very clever design where
there are two metal strips in contact with each other that have springiness to
them, so, they would normally not be in contact. During assembly, the fuse
cavity is filled with a waxy material, consistency dependent
The original fuse, per the 10811 manual, is P/N 10811-80008 which Keysight
lists as obsolete.
The part description lists it as 'Fuse-Thermal 115C 1.0A 250V', which I
interpret to be 115 degrees C.
Hope this helps.
Joe
-Original Message-
From: time-nuts
___
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.
22 matches
Mail list logo
