Tom Van Baak said the following on 05/30/2009 03:44 PM:
... as long as you remember to use TI+/- mode.
For stuff like this I use plain old TI mode and just set the
UUT 1pps to lag the reference 1pps by a fraction of a
second, or maybe even just a couple of microseconds.
That way you get a sma
In message <81fa4fd1186b4407be773c83adf59...@pc52>, "Tom Van Baak" writes:
>> ... as long as you remember to use TI+/- mode.
>
>For stuff like this I use plain old TI mode and just set the
>UUT 1pps to lag the reference 1pps by a fraction of a
>second, or maybe even just a couple of microseconds.
1) are you comparing two relatively stable 1pps sources, or
If (1), then any time interval counter will work for you. There
is no issue of "dead time" or "continuous" measurement. You
can calculate ADEV directly from the raw output of the 5370,
because it is giving you a periodic series of time i
In message <7487a8e5980845359b6047d0e84c6...@pc52>, "Tom Van Baak" writes:
>1) are you comparing two relatively stable 1pps sources, or
>
>If (1), then any time interval counter will work for you. There
>is no issue of "dead time" or "continuous" measurement. You
>can calculate ADEV directly from
I'm not sure it's possible to make continuous stability measurements (Allan
deviation, etc.) directly with a 5370 since they don't support
running/overlapped measurements between readings.
John,
It depends on what you mean by "readings". Or on what the
two sources are:
1) are you comparing two
Magnus wrote:
Having 1-10 kW per rack is not uncommon these days, so
forced convection needs to be done
That and more. A fully loaded 42U rack of HP C-class blades runs 8 kW idle and
peaks at 24 kW.
This can be air cooled (easily) in a properly designed and commissioned
run-of-the-mill rais
At 07:38 PM 5/23/2009, Tom Clifton wrote...
Turned out being a lot harder than I had anticipated as the internal
ground planes on the Dell Motherboards made the old caps dogs to
remove, and the new ones very hard to solder back in without cold
joints.
Get some Chipquik ( http://www.chipquikin
anley
- Original Message
From: Magnus Danielson
To: Discussion of precise time and frequency measurement
Sent: Saturday, May 23, 2009 6:45:10 PM
Subject: Re: [time-nuts] 5070B once more (actually capacitors)
Tom Clifton skrev:
> The word we got from our Dell National Accounts rep
Tom Clifton skrev:
The word we got from our Dell National Accounts rep was that there was a run of
contaminated electrolyte affectring several capacitor manufactures. Gee, go
figure QC issues in a country still painting toys with lead based paint...
Any way, I recently purchased a pile of low
The word we got from our Dell National Accounts rep was that there was a run of
contaminated electrolyte affectring several capacitor manufactures. Gee, go
figure QC issues in a country still painting toys with lead based paint...
Any way, I recently purchased a pile of low ESR caps from Mouser
In message <980094.92979...@web27105.mail.ukl.yahoo.com>, Robert Atkinson write
s:
>
>I'm not sure if the espionage story is true.
It is:
http://www.theregister.co.uk/2003/02/06/stolen_formula_torpedos_big_brand/
--
Poul-Henning Kamp | UNIX since Zilog Zeus 3.20
p...@freebsd.org
The capacitor espionage story is quite true and well known to just about
everybody in the computer industry. Google "capacitor corporate espionage" for
a start. First hit is: http://www.burtonsys.com/bad_BP6/story1.html from IEEE
Spectrum. More than one cap maker got the bad juice...
--
e new.
Rober G8RPI
--- On Sat, 23/5/09, g4...@g4fre.com wrote:
> From: g4...@g4fre.com
> Subject: Re: [time-nuts] 5070B once more (actually electrolytics)
> To: time-nuts@febo.com
> Date: Saturday, 23 May, 2009, 2:30 PM
> I just got hit by this issue in my
> Dell GX270. Its
On Behalf Of g4...@g4fre.com
> Sent: Saturday, May 23, 2009 8:30 AM
> To: time-nuts@febo.com
> Subject: Re: [time-nuts] 5070B once more (actually electrolytics)
>
> I just got hit by this issue in my Dell GX270. Its the one i
> use for HPIB instruments/Heather. The video out
it
isn't *always* the electrolytics that are to blame!
-- john, KE5FX
> -Original Message-
> From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com]on
> Behalf Of g4...@g4fre.com
> Sent: Saturday, May 23, 2009 6:30 AM
> To: time-nuts@febo.com
> Subject
g4...@g4fre.com skrev:
I just got hit by this issue in my Dell GX270. Its the one i use for
HPIB instruments/Heather. The video output disappeared. Doing a web
search i found lots of posts on they used faulty capacitors. They didnt
do a recall as it would lead to "bad customer perception of Del
(they had
just done a battery recall).
Upon examination 2 had "bulged" You can get kits to replace all 18
electrolytics. It may explain why there are a lot of gx260/270/280 unsold on
ebay recently
Dave
Message: 5
Date: Fri, 22 May 2009 23:01:38 +
From: Mark Sims
Subjec
In message , Mark Sims writes:
>
>Many failed electrolytic caps on PC motherboards and in PC power supplies
>can be traced to a case of industrial espionage gone wrong. [...]
While this tale is true, the fact is that even without incompetence,
electrolytics suck.
--
Poul-Henning Kamp | UN
Many failed electrolytic caps on PC motherboards and in PC power supplies can
be traced to a case of industrial espionage gone wrong. Somebody sole the
formula for the caps from a Japanese company and sold it to a competitor. That
competitor allegedly cranked out over a billion of the caps an
Poul-Henning Kamp wrote:
> It is worth pointing out that a very large fraction of all electronics
> failures are not semiconductors but electrolytic capacitors.
>
> People are often astonished when I tell them, that a "long life"
> electrolytic capacitor is one which will last one year at its rated
Mark Sims skrev:
The power dissipated in a modern CPU chip (watts per sq cm) far exceeds that of
a cooking hotplate. There are some videos on YouTube showing CPU's literally
exploding when they loose cooling for just a short time. ECL is a rather
chilly iceberg in comparison...
The Cray-1,
Poul-Henning Kamp skrev:
In message <4a170da2.3080...@rubidium.dyndns.org>, Magnus Danielson writes:
Hal Murray skrev:
There are being books written about this. One that I have found being a
fairly short but useful one is the AT&T Reliability Manual.
It is worth pointing out that a very lar
In message <971f24636bd13158d9fe412ec6c9c885.squir...@webmail.sonic.net>, "Rick
Karlquist" writes:
>The old photos of Len Cutler watching the airline porters carrying
>the clock up the stairs to the plane give the impression that
>the airline was honored to be asked to participate.
According to
In message <4a170da2.3080...@rubidium.dyndns.org>, Magnus Danielson writes:
>Hal Murray skrev:
>There are being books written about this. One that I have found being a
>fairly short but useful one is the AT&T Reliability Manual.
It is worth pointing out that a very large fraction of all electron
M. Warner Losh wrote:
> In message: <20090522185851.4137db...@ip-64-139-1-69.sjc.megapath.net>
> Hal Murray writes:
> :
> : rich...@karlquist.com said:
>> : Did you have any trouble convincing the airlines and/or FAA that it was
> safe
> : to take an atomic clock on a plane?
I never h
The power dissipated in a modern CPU chip (watts per sq cm) far exceeds that of
a cooking hotplate. There are some videos on YouTube showing CPU's literally
exploding when they loose cooling for just a short time. ECL is a rather
chilly iceberg in comparison...
--
Hal Murray wrote:
The reason for the fans is to prevent premature failures of the
silicon devices due to thermal degradation. The life of a silicon
chip is halved for every 10C temperature increase, more or less.
I was going to make a similar comment, but got sidetracked poking around
google.
Hal Murray skrev:
The reason for the fans is to prevent premature failures of the
silicon devices due to thermal degradation. The life of a silicon
chip is halved for every 10C temperature increase, more or less.
I was going to make a similar comment, but got sidetracked poking around
google.
In message: <20090522185851.4137db...@ip-64-139-1-69.sjc.megapath.net>
Hal Murray writes:
:
: rich...@karlquist.com said:
: > First of all, the 5071A has to be able to run on a battery, so you can
: > do the flying clock experiment.
:
: Did you have any trouble convincing the airline
> The reason for the fans is to prevent premature failures of the
> silicon devices due to thermal degradation. The life of a silicon
> chip is halved for every 10C temperature increase, more or less.
I was going to make a similar comment, but got sidetracked poking around
google. I didn't fin
Hi!
Regarding the comments below on the 5370: there are always two
questions with temperature: meeting spec and reliability. Instruments
vary as to which is a bigger issue. Some have temperature
proof measurement techniques that will work virtually until
something burns up, so you can get lu
rich...@karlquist.com said:
> First of all, the 5071A has to be able to run on a battery, so you can
> do the flying clock experiment.
Did you have any trouble convincing the airlines and/or FAA that it was safe
to take an atomic clock on a plane?
I'd be more worried about the big batteries tha
In message , Mark Sims writes:
>I was rather surprised to see that, if anything, the internal jitter went
> down a couple of picoseconds
That could easily be reduced microphonics in the OCXO because the new
fan does not rattle around as much.
--
Poul-Henning Kamp | UNIX since Zilog Zeu
When I swapped my 5370A AC fans for DC fans I was concerned that the inverter
in the fan motors might have some effect on the performance of the
instrument... after all, it is measuring stuff at the part per trillion level.
I was rather surprised to see that, if anything, the internal jitter
In message <4267588cdd7544d48a9a119584228...@pc52>, "Tom Van Baak" writes:
>I'm sure this requires no small effort in thermal engineering on
>their part.
The major part of this effort was to reduce the power usage to
maximize battery lifetime.
>The plot you get is then simply accuracy (or jitter
At 10:13 AM -0700 5/22/09, Tom Van Baak wrote:
One comment, and one idea on airflow...
I'm sure we could discuss for some time what airflow is too much
or too little or where to place the thermal probes or how to take IR
scans or how then interpret them. But it seems to me the bottom
line is no
Tom Van Baak wrote:
> One comment, and one idea on airflow...
>
> I've noticed that none of my high-end frequency standards use
> fans at all. That includes every Rb, Cs, and H-maser. This does
> not mean they are all cool to the touch, but my guess is it's better
> to allow temperature gradients t
One comment, and one idea on airflow...
I've noticed that none of my high-end frequency standards use
fans at all. That includes every Rb, Cs, and H-maser. This does
not mean they are all cool to the touch, but my guess is it's better
to allow temperature gradients to exist than use fans in an at
I came home one day to find *that* smell in my workshop. It turned out to be
my HP 3325B. It had been on for ages and it had also been a warm day. I
looked at the back and found the intake completely blocked up with dust.
It seems to still work, but I need to open it right up and check it out
prop
A8? Reference buffer? Gee, I thought was the electrostatic dust magnet ;-)
That puppy can grow more fuzz than a sheepdog. In all the machines I have
worked on, it was utterly disgusting.
BTW, the best way to locate where to drill the access hole for the oscillator
tuning pot is to look
The ECL and EECL chips are located on A22 (arming board), A19 + A20
(interpolator boards), A18, A17 (count chain assembly) A8 (reference
buffer), A21 (multiplier assembly).
The interpolator boards are more or less directly in line with the
ducted airflow from the fan as are the reference buffer a
When I worked in R&D at HP's Microwave Division (1972 ~ 1976) and HP LaserJet
Division (1976 ~ 2000) we designed all our products to meet specifications
across a temperature range of -20 to +55 degrees Centigrade. I would assume
this was a standard requirement across most if not all HP products
Hello Karl,
When I tested my quiet 12V fans in the 5370As, I placed 6 thermocouples around
the guts of the machine. I made a point of sticking a couple of them on
heatsinked chips. The new fan made no significant difference in the readings
on any of the thermocouples. All the readings wer
Hal Murray wrote:
> How much ECL is used in a 5070?
A bunch
How tightly are they packed?
You need a high cooling velocity even if just one chip.
> How much of
> the heat goes directly from the chip to the air rather than from chip to
> board to air?
A substantial amount of cooling is from DIP
> This is incorrect. ECL components require a minimum airflow velocity
> that is rather high. The purpose of the large fan is to maintain this
> velocity. If a smaller fan is used, the ECL components will get
> hotter, even though the air flowing past them is not much hotter.
> When you say the
pointed out by others.
Didier
-Original Message-
From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On
Behalf Of Poul-Henning Kamp
Sent: Thursday, May 21, 2009 12:12 PM
To: Discussion of precise time and frequency measurement
Subject: Re: [time-nuts] 5070B once more
> -Original Message-
> From: time-nuts-boun...@febo.com
> [mailto:time-nuts-boun...@febo.com] On Behalf Of Richard
> (Rick) Karlquist
> Sent: Thursday, May 21, 2009 9:26 AM
> To: Discussion of precise time and frequency measurement
> Subject: Re: [time-
In message <4a15808f.4090...@karlquist.com>, "Richard (Rick) Karlquist" writes:
>"Modern" fans obey the same laws of physics as the original equipment.
>They don't magically produce more airflow for less noise.
Agreed: there is no magic to it.
But a lot has happened in aerodynamics since Hermann
Mark Sims wrote:
I have done quite a bit of work replacing fans in old equipment with modern
fans.
I have never seen a case where replacing a hurricane level fan with a
whisper
quiet fan made any real difference in the cooling inside the unit...
typically
one sees less than +/- 5C dif
I have done quite a bit of work replacing fans in old equipment with modern
fans. I have never seen a case where replacing a hurricane level fan with a
whisper quiet fan made any real difference in the cooling inside the unit...
typically one sees less than +/- 5C difference anywhere inside t
When I have been concerned with 'stealing' power, I have used
a switching power supply wall wart. Small and are usually quite
efficient. One model a Sony (branded), the chip inside even had
a opto isolated control pin so it could be turned on/off via
logic.
-pete
>
>
> Yes, I have replaced the
t; I have an HP 5334A, and a HP5335A, the latter being more obtrusive. Perhaps
> the design considerations were based on the US, with its higher summer
> temperatures,not such a problem for us Europeans.
> Roy
>
>
>
> - Original Message -
> From: "Mark Sim
The fan in the 5370x & other counters is bolted directly to the
chassis. I've found that it can be isolated by rubber grommets
from the chassis yielding a significant reduction in noise. Some
adhesive backed foam (weather-stripping) is needed around the
chassis opening to seal up the bypass path
Subject: [time-nuts] 5070B once more (actually 5370A fans)
Yes, I have replaced the fans in four 5370A and 5370B counters with modern
12V brushless DC motor units connected to the 10V supply. VERY nice and
quiet. I did before and after thermocouple tests in the chassis. The
tempera
Yes, I have replaced the fans in four 5370A and 5370B counters with modern 12V
brushless DC motor units connected to the 10V supply. VERY nice and quiet. I
did before and after thermocouple tests in the chassis. The temperatures were
basically unchanged (+/- 3C). Variances could easily ha
> Has anybody tried to replace these
> fans with a
> more modern type (12/24 volt). I'm sure the designers were being very
> proper, but I cannot believe that a counter should require such a large
> volume of air moving through it ?
> I have an EIP 545 Counter and
> an HP 5335A
> which both have Pa
an
if running on that supply.
Just a thought..
Rob K
-Original Message-
From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On
Behalf Of Roy Phillips
Sent: 20 May 2009 10:16
To: Discussion of precise time and frequency measurement
Subject: Re: [time-nuts] 5070B once
Papst fans and are very noisy
> Any ideas on this.
> Roy
>
> - Original Message -
> From: "Pierre-François (f5bqp_pfm)"
> To:
> Sent: Wednesday, May 20, 2009 9:54 AM
> Subject: [time-nuts] 5070B once more
>
>
>> Hi The Gang,
>>
>&
5335A
which both have Papst fans and are very noisy
Any ideas on this.
Roy
- Original Message -
From: "Pierre-François (f5bqp_pfm)"
To:
Sent: Wednesday, May 20, 2009 9:54 AM
Subject: [time-nuts] 5070B once more
Hi The Gang,
I've revitalized my 5070B I got few y
ts-boun...@febo.com] Im Auftrag von
> Pierre-Francois (f5bqp_pfm)
> Gesendet: Mittwoch, 20. Mai 2009 10:55
> An: time-nuts@febo.com
> Betreff: [time-nuts] 5070B once more
>
>
> Hi The Gang,
>
> I've revitalized my 5070B I got few years ago and since a
> w
Hi The Gang,
I've revitalized my 5070B I got few years ago and since a week or two it has
seen again passing into it few electrons after so long... lol...
Now I'm wondering which software I could use to grab data from it to the PC and
then to analyze the buffers to see the stability of my rubidi
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