Thanks a lot for this tip, i´ve already found a lot of info there.
Daniel
Em 29/03/2013 20:22, Ed Palmer escreveu:
Yes, they're all online. Here's the link:
http://www.hpl.hp.com/hpjournal/pdfs/IssuePDFs/hpjindex.html
The best way to find a model # would be to use google's site: command
Moin,
I'm currently reading up some stuff on optical PLLs and am stuck with some
details i cannot find any data on.
The goal is to make two lasers locked with about 7GHz of offset to eachother.
So far, i figured out that PIN photodiodes can go up to several 100MHz
transition frequency and
On Thu, 28 Mar 2013 21:01:27 -0400
paul swed paulsw...@gmail.com wrote:
OK it has been a while and I have promised to share results. In the next
few days I will put whats on paper into a schematic and share. I won't
dwell on all of the stuff from October to now. But several front end rcvrs,
Hi
If you go back into the papers from the early 1980's there is one where they
used a high gain antenna and no knowledge of the coding scheme to pull timing
off of GPS. I believe it was at White Sands, but that could be wrong.
Bob
On Mar 29, 2013, at 11:42 PM, Stewart Cobb
On 3/29/13 9:01 AM, Bob Camp wrote:
Hi
Too much tuning range is easy enough to fix. Use a pot to set it on frequency and then
hook it to the rest of the stuff with a fixed resistor. The gotcha would be
if the poor thing drifts so much that it *needs* the wide range to stay in lock.
My guess
On 3/30/13 5:31 AM, Bob Camp wrote:
Hi
If you go back into the papers from the early 1980's there is one where they
used a high gain antenna and no knowledge of the coding scheme to pull timing
off of GPS. I believe it was at White Sands, but that could be wrong.
One can just run it into
Hi
I think it's pretty safe to say that the Vectron part mentioned is a VCXO with
a crystal as the resonator. Indeed a ceramic resonator or an L/C resonator part
would have a bit more drift and lower Q than a crystal based part. I would not
try something like this with anything other than a
Hi
A, but they did recover the code in addition to the carrier frequency.
Given enough gain (and thus directivity) they were able to capture the full
transmission from a single bird. They could not pull the almanac data off of
it, but the sat's orbital parameters are relatively easy to
Hi Attila,
The goal is to make two lasers locked with about 7GHz of offset to
eachother.
So far, i figured out that PIN photodiodes can go up to several 100MHz
transition frequency and avalanche photodiodes are available up to 2GHz.
If you need photodiode response only near 7 GHz, as
You'll need a photodiode that can detect photons at your lasers'
wavelength. You may be able to use a photodiode at a shorter than its
design wavelength as long as there are not coatings (eg anti-reflection)
that block the wavelength of interest. You'll need to make sure that
both lasers
We are looking into using two N/E550XA/B Phase Noise systems and the 89410A to
build a Cross Correlated measurement system.
I was wondering if anyone has attempted this before? Does anyone know where to
find the base GPIB command codes for the 70420A system?
Thanks;
Thomas Knox
Phase Noise
I don't think that you can effectively directly mix two laser
wavelengths in a semiconductor light detector and get a useable IF -
it's hard enough just to get the tens of GHz modulation signals out
above the noise floor, let alone a tiny difference signal between
hundreds of THz. You need an
You lose me at damping per decade? Is damping the right word? Do you mean high
frequency rolloff?
Most texts on photodiodes go into bootstrapping them to reduce the effect of
capacitance. But if you design fully differential amplifier circuits, they have
the same effect as bootstrapping.
I used UDT PIN10 photodiodes to observe the mode spacings in HeNe lasers.
The typical mode spacings were around 600 MHz.
John WA4WDL
--
From: ed breya e...@telight.com
Sent: Friday, March 29, 2013 8:20 PM
To: time-nuts@febo.com
Subject: Re:
My understanding is that you want to operate photodiodes with high reverse
bias for the best frequency response. The bias widens the space charge
layer, thereby reducing the capacitance of the device. The high electric
fields in the SCL region also sweeps the hole-electron pairs, produced by
I forgot to mention if you use the bootstrap technique, you can keep a negative
bias on the photodiode, which improves bandwidth by reducing capacitance. That
is, you drive the AC signal across the diode to zero, but not the DC bias. If
you use the fully differential amplifer, then the bias
You might take a look at these:
http://www.ebay.com/itm/360601919160?ssPageName=STRK:MEWNX:IT_trksid=p3984.m1497.l2649#ht_780wt_911
They have a fiber terminated Avalanche PD and built in HV supply from 5
volts. Cheap at $5 each.
Tom
- Original Message -
From: J. Forster
Hi Tom:
I work for Agilent. Have you asked your Agilent support engineer
about this? There is some internal work going on in Agilent
involving cross correlation. The guy doing it had to get access
to source code. I'm not sure if there is a solution available
for customers, but I would like to
Moin Peter,
On Sat, 30 Mar 2013 09:47:26 -0700
Peter Monta pmo...@gmail.com wrote:
The goal is to make two lasers locked with about 7GHz of offset to
eachother.
So far, i figured out that PIN photodiodes can go up to several 100MHz
transition frequency and avalanche photodiodes are
On Sat, 30 Mar 2013 10:00:08 -0800
David McQuate mcqu...@sonic.net wrote:
You'll need a photodiode that can detect photons at your lasers'
wavelength.
Yes, of course.
You may be able to use a photodiode at a shorter than its
design wavelength as long as there are not coatings (eg
On Fri, 29 Mar 2013 17:20:35 -0700
ed breya e...@telight.com wrote:
I don't think that you can effectively directly mix two laser
wavelengths in a semiconductor light detector and get a useable IF -
it's hard enough just to get the tens of GHz modulation signals out
above the noise floor,
On Sat, 30 Mar 2013 17:29:45 +
li...@lazygranch.com wrote:
You lose me at damping per decade? Is damping the right word?
Do you mean high frequency rolloff?
Er.. yes. Frequency rolloff... Sorry, my native language got the better of me.
Most texts on photodiodes go into bootstrapping
On Sat, 30 Mar 2013 13:46:51 -0400
jmfranke jmfra...@cox.net wrote:
I used UDT PIN10 photodiodes to observe the mode spacings in HeNe lasers.
The typical mode spacings were around 600 MHz.
This sounds interesting. According to the datasheet i've found,
the PIN10D has a response time of 25ns,
On 30 March 2013 11:48, Attila Kinali att...@kinali.ch wrote:
Moin,
I'm currently reading up some stuff on optical PLLs and am stuck with some
details i cannot find any data on.
The goal is to make two lasers locked with about 7GHz of offset to eachother.
So far, i figured out that PIN
On Sat, 30 Mar 2013 10:52:54 -0700 (PDT)
J. Forster j...@quikus.com wrote:
My understanding is that you want to operate photodiodes with high reverse
bias for the best frequency response. The bias widens the space charge
layer, thereby reducing the capacitance of the device. The high electric
Maybe I'm jaded a bit, but in this town the sub-10GHz optical stuff is
considered kinda slow. The guys down the street, Picometrix, have been doing
40+GHz optical receivers for over 15 years. They claim 1.5G to 100G and from
400nm to 1650nm so probably they can help. http://www.picometrix.com/
On Sat, 30 Mar 2013 18:43:03 +
David Kirkby david.kir...@onetel.net wrote:
I would contact Hammamatsu Photonics
http://www.hamamatsu.com
and see if they can help. They might havae something in development,
that is not on the web site. If you are in a uni, they might be
especially
On Sat, 30 Mar 2013 12:45:52 -0700 (PDT)
Robert LaJeunesse rlajeune...@sbcglobal.net wrote:
Maybe I'm jaded a bit, but in this town the sub-10GHz optical stuff is
considered kinda slow. The guys down the street, Picometrix, have been doing
40+GHz optical receivers for over 15 years. They
A photodiode is in fact a nonlinear device for optical fields as it is
essentially a linear optical power detector.
The output is proportional to the incident optical power not the field
amplitude.
Photomixers are routinely used in wide range of diverse application such
as translating the
The circuit is something like the instrumentation amplifier. The description
starts on page 207 with a schematic on page 208. I can scan it later, but the
circuit is easy to describe. Think of two op amps in the classic current
multiplication (I to V) circuit, that is positive input to ground
The reciever is now drawn up in expressPC. Will add in the dividers to
another drawing I simply could not get it all in the same schematic. Not
that there is a lot expressPC has sizing limitations. I know there is
better... Just no time to tinker.
Its going to be interesting getting the schematics
What a bunch of hooey. Another so called expert wasted hours of my time
because he can't be bothered to either note that code is buggy or just
can't be bothered..
If you don't want to release it, then don't. If you do and it's a POS,
Expect emails.
On Thu, Mar 28, 2013 at 2:16 PM, NeonJohn
Hi
The easy way to get to pdf is normal a pdf translator loaded as if it's a
printer. Anything that will print can (at least in theory) be translated to a
pdf by this approach. In real life, nothing is ever perfect, but I've had good
luck with them.
Bob
On Mar 30, 2013, at 5:41 PM, paul
Ooops - never mind. I wrote before my memory was updated. My
experience in E-O stuff was years ago using AM at relatively low
frequency, and nowhere near the lasers and microwave/gigabit/sec
stuff - I didn't think the detectors were fast enough to actually
keep up with the optical carrier
The circuit I've seen is:
|--||---
+Vb---o--| amp
|--||-o-
Vb gnd--|
The diode is reverse biased by 50 to several hundred volts.
The two caps are DC bypass caps w/ very short leads.
The output is a
The detectors don't have to be fast enough to keep up with optical
carrier frequency as long as the incident optical power has a component
at a much lower frequency.
Bruce
ed breya wrote:
Ooops - never mind. I wrote before my memory was updated. My
experience in E-O stuff was years ago using
If I can rephrase that it it, the diode needs to see the difference signal of
the mixer?
-Original Message-
From: Bruce Griffiths bruce.griffi...@xtra.co.nz
Sender: time-nuts-boun...@febo.com
Date: Sun, 31 Mar 2013 11:43:48
To: Discussion of precise time and frequency
Hi, Tom --
A paper in the 2010 EFTF described the use of a pair of 11848A boxes from
the 3048A system, which is similar to the E5500 hardware (
http://www.congrex.nl/EFTF_Proceedings/Papers/Session_14_Oscillators_and_Noi
se/14_04_Bale.pdf ). You could ping those authors if you haven't already.
Yes, the beat (difference) frequency of the 2 lasers has to lie within
the photodiode electrical passband.
With a suitable low noise tunable LO (laser) the frequency spectrum
beyond the photodiode electrical bandwidth can be explored.
Bruce
li...@lazygranch.com wrote:
If I can rephrase
Oops, sorry, I read 70820 for 70420, disregard that last link.
-- john, KE5FX
Miles Design LLC
-Original Message-
From: time-nuts-boun...@febo.com [mailto:time-nuts-
boun...@febo.com] On Behalf Of John Miles
Sent: Saturday, March 30, 2013 4:10 PM
To: 'Discussion of precise time
On Sat, Mar 30, 2013 at 2:58 PM, Lizeth Norman normanliz...@gmail.com
wrote:
If you don't want to release it, then don't. If you do and it's a POS,
Expect emails.
Some I know use a dedicated email address when they post things intended
as open source. They then set up an auto-respond
On 30 March 2013 19:50, Attila Kinali att...@kinali.ch wrote:
On Sat, 30 Mar 2013 18:43:03 +
David Kirkby david.kir...@onetel.net wrote:
I would contact Hammamatsu Photonics
http://www.hamamatsu.com
This might be a good idea. Thanks!
I played tricks during my Ph.D. of gain-modulating
OK, so if you just need to detect the mixer difference, the band limiting of
the photodiode is a feature. ;-)
-Original Message-
From: Bruce Griffiths bruce.griffi...@xtra.co.nz
Date: Sun, 31 Mar 2013 12:28:59
To: li...@lazygranch.com; Discussion of precise time and frequency
k7...@arrl.net said:
Some I know use a dedicated email address when they post things intended as
open source. They then set up an auto-respond message such as:
Auto-responders are evil. The problem is that spammer's forge the return
address. The response to any spam that gets past your
If you write something and want to publish it. Put it one Source
Forge and then you get Subversion system to host the code, an email
list people can join and a forum that is linked to it and bug tracking
and so on and so on. You can keep up with the forum that is tied to
your code or not.
Hi Miles;
Thanks for the paper. Craig is actually the one taking the lead on this
project. I will keep the group updated on the project.
Thomas Knox
From: jmi...@pop.net
To: time-nuts@febo.com
Date: Sat, 30 Mar 2013 16:10:21 -0700
Subject: Re: [time-nuts] Building a Agilent Cross
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