[time-nuts] Lamp for FRK Rubidium Needed

2014-06-20 Thread Doug Millar
Hi, Does anyone have a good Rb lamp available for an Efratom FRK?  

   Doug K6JEY  (drzarko...@yahoo.com)
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Re: [time-nuts] Lamp for FRK Rubidium Needed

2014-06-20 Thread Chuck Harris

Just in case you weren't aware, bad lamps can often be
resurrected by the judicious application of heat.  The idea
is to heat the bulb enough to evaporate all of the Rb
that is deposited on the glass (making it black), and then
let the lamp cool.   The Rb will again condense out on the
glass, but this time it will condense out where the lamp
is coolest, and will spare the rest of the bulb, allowing
the light to get out.

-Chuck Harris



Doug Millar wrote:

Hi, Does anyone have a good Rb lamp available for an Efratom FRK?

Doug K6JEY  (drzarko...@yahoo.com)
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Re: [time-nuts] HP E3610A Power supply

2014-06-20 Thread paul swed
Exactly lets face it someone at Gmail screwed up or there was a serious
attack.
I also noticed my inbox was pretty thin. Now this morning its more normal.
The issue has run longer then a few days as this is the tread that I
started to notice something funny on.

Regards
Paul
WB8TSL


On Thu, Jun 19, 2014 at 10:54 PM, Didier Juges shali...@gmail.com wrote:

 Tom,

 I just started getting messages again today after almost a week of getting
 nothing.

 This account is on gmail

 No idea what happened...

 Didier KO4BB


 On June 18, 2014 10:42:25 PM CDT, Tom Van Baak t...@leapsecond.com wrote:
 Paul,
 
 The E3610A posting was a good one. This explains why some high-end
 oscillator sockets have a fuse, series diode, and zener shunt -
 protects the expensive oscillator from both reverse- and over-voltage.
 
 I'll look into the spam issue. If there's more than a couple contact me
 off-list and we'll debug it.
 We've been having issues with aol, yahoo, comcast postings recently.
 Might be related.
 
 When in doubt, you can always read messages at:
 http://www.febo.com/pipermail/time-nuts/
 
 Sometimes it's actually more convenient to read them there by author or
 thread than by inbox.
 
 /tvb
 
 - Original Message -
 From: paul swed paulsw...@gmail.com
 To: Discussion of precise time and frequency measurement
 time-nuts@febo.com
 Sent: Wednesday, June 18, 2014 7:41 PM
 Subject: Re: [time-nuts] HP E3610A Power supply
 
 
  Bert just finding out that google mail is treating your emails as
 spam!
  Not sure if the message appears but as you can see it questions who
 you are.
  I found numbers of missing emails a few minutes ago.
  Regards
  Paul
  WB8TSL
 
 
  On Thu, May 22, 2014 at 7:59 AM, ewkeh...@aol.com wrote:
 
  This may be off topic but I did check with Tom and many time nuts
 may have
  HP E3610A power supplies on their bench and mine smoked a ublox GPS
 so that
   makes it topic related..
  The reference section has some 1 uF 50V capacitors and in my unit
 one
  shorted. The reference section has fuses on the board but they did
 not
  open. The
   7912 overheated and shorted out,  traces are discolored the op amp
 shows
  signs of overheating and burned out. The result was the output went
 to
  30V+
   and next morning the ublox chip plastic showed where the chip
 smoked. As
  a minimum I recommend replacing the 1 uF capacitors with new quality
  caps,
  I also ordered 15 V 5 W zeners and 0.5 A 20 mm glass fuses.
  Bert Kehren
 
 
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 --
 Sent from my Motorola Droid Razr HD 4G LTE wireless tracker while I do
 other things.
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Re: [time-nuts] HP E3610A Power supply

2014-06-20 Thread Paul
On Fri, Jun 20, 2014 at 9:04 AM, paul swed paulsw...@gmail.com wrote:

 someone at Gmail screwed up or there was a serious
 attack.


https://help.yahoo.com/kb/email-service-providers-send-yahoo-addresses-sln24016.html
ditto AOL

This is what Yahoo and AOL want to happen.  If you don't like their tactics
move off AOL/Yahoo and/or encourage your correspondents to do so.  The
burden shouldn't be on the list owners.
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Re: [time-nuts] Lamp for FRK Rubidium Needed

2014-06-20 Thread paul swed
Chuck is correct I have done this trick on FRS units. The glass clears and
the lamp re-ignites and continues to work for a long time. Actually it
hasn't failed and this must be 2 years now.
Regards
Paul
WB8TSL


On Fri, Jun 20, 2014 at 8:34 AM, Chuck Harris cfhar...@erols.com wrote:

 Just in case you weren't aware, bad lamps can often be
 resurrected by the judicious application of heat.  The idea
 is to heat the bulb enough to evaporate all of the Rb
 that is deposited on the glass (making it black), and then
 let the lamp cool.   The Rb will again condense out on the
 glass, but this time it will condense out where the lamp
 is coolest, and will spare the rest of the bulb, allowing
 the light to get out.

 -Chuck Harris



 Doug Millar wrote:

 Hi, Does anyone have a good Rb lamp available for an Efratom FRK?

 Doug K6JEY  (drzarko...@yahoo.com)
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Re: [time-nuts] FASTRAX GPS

2014-06-20 Thread Tom Van Baak
Hi Ernie, Jason, (also Hal, Chris),

I'm able to get NMEA and 1PPS out of the Fastrax/iTrax130 board now.

Before I sink any more time into this project, have any of you made 1PPS 
measurements?

Compared to ublox, using the same antenna, these units take tens of minutes or 
even hours to lock. And they have a bad habit of being close to UTC for a few 
hours but then gradually wandering off by tens or hundreds of microseconds.

A power cycle puts them back on track (aligned with UTC), so it would seem to 
be a firmware issue rather than antenna or reception. A similar thing happens 
on three different boards I have evaluated over the past two weeks.

Now, when they are working right, the 1PPS has an RMS deviation of around 20 
ns, which I've come to expect as typical for cheap GPS/1PPS receivers these 
days. But the long lock times and unexplained 1PPS drift make them unreliable 
for GPSDO or serious timing work, even at $12 each.

It might be me, so I'm asking if you've seen anything similar. The binary 
command set looks tempting, but I usually don't play with that until the unit 
can be trusted to give reliable NMEA and 1PPS output.

Unfinished page: http://leapsecond.com/pages/itrax/

/tvb

- Original Message - 
From: Ernie Peres erniepe...@aol.com
To: time-nuts@febo.com
Sent: Wednesday, June 11, 2014 4:11 AM
Subject: Re: [time-nuts] FASTRAX GPS


 
 Hi Jason,
 
 
 I figured out a different pin assignments
 
 hold the PCB so that the SMA antenna connector is looking to right and under 
 the PCB.
 
 open-   1  2-  Ant powerpresently connected to pin nbr 4
TX-   3  4-  Main power  +3 volt
 RX-  5  6-  1PPS
 open-   7  8-  Grnd   power -3 Volt
 
 the unit takes about 60mA @ 3,0 volt and comes-up in NMEA mode.. 9600 Baud.
 I use the FASTRAX_WORKBENCH_522 software.
 I wonder if anybody has other pin arrangement/connection. The 2 open pins is 
 UNK and also not sure if pin nbr 4 is the main power or perhaps the pin nbr 
 2..??
 
 Rgds Ernie.
 


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Re: [time-nuts] FE5680 GPS Disciplined Controller

2014-06-20 Thread Tom Van Baak
 First getting 1 E-13 per second accuracy is not possible with a FE5680  
 because of tuning steps of 6.8 E-13. Even 1 E-12 may not be possible.

Bert,

I'm pretty sure the short-term noise of Rb standards like FE5680 is 
significantly greater than the DAC resolution in your case. See the ADEV plot 
at http://www.ke5fx.com/rb.htm for example. Therefore -- all you have to do is 
dither the DAC to achieve whatever fractional frequency or phase resolution you 
want.

You can change the DDS tuning words almost as many times per minute or per 
second as you wish to achieve the desired average accuracy. Don't let the LSB 
spec limit you. Remember all our discussions about frequency and phase tuning 
words on your AD9913 project (www.leapsecond.com/pages/ad9913/).

/tvb

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Re: [time-nuts] Lamp for FRK Rubidium Needed

2014-06-20 Thread Peter


paul swed paulswedb@... writes:

 
 Chuck is correct I have done this trick on FRS units. The glass clears and
 the lamp re-ignites and continues to work for a long time. Actually it
 hasn't failed and this must be 2 years now.
 Regards
 Paul
 WB8TSL
 
 On Fri, Jun 20, 2014 at 8:34 AM, Chuck Harris cfharris@... wrote:
 
  Just in case you weren't aware, bad lamps can often be
  resurrected by the judicious application of heat.  The idea
  is to heat the bulb enough to evaporate all of the Rb
  that is deposited on the glass (making it black), and then
  let the lamp cool.   The Rb will again condense out on the
  glass, but this time it will condense out where the lamp
  is coolest, and will spare the rest of the bulb, allowing
  the light to get out.
 
  -Chuck Harris
 
 

Chuck and Paul

Do you have any more specific information on how to do this?

I also have an FRK that has a lamp that is failing to run consistantly, and
would like to try this to resurrect it.

I am afraid of doing more harm than good without some good guidance.

regards

peter
G0RSQ

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Re: [time-nuts] Lamp for FRK Rubidium Needed

2014-06-20 Thread paul swed
OK so the scientific method. NOT.
The FRKs are nice in that you can get to the pellet pretty easily from the
posts I have seen on time-nuts. The FRS you have to break a glass cover.
Much like a very thin microscope cover slide. No way to fix that and I am
sure it matters only it doesn't seem to.
Heat the bulb with a heat gun it will get pretty hot so you need something
to hold the bulb.
Couple of things will happen. The black stuff will disapear very slowly Or
most likely a blob will form at the bottom or low spot. This blob needs to
be heated and gently rolled back just by tilting it in the direction you
want it to go in. You want it away from the emission end of the buld. As
you heat it will slowly vaporize so you want to gently do this until its
gone.
Do not go red hot on anything you will get a feel. Peter I actually suspect
you will come back with far better guidance then I have given here.
Regards
Paul
WB8TSL


On Fri, Jun 20, 2014 at 2:46 PM, Peter pe...@g0rsq.co.uk wrote:



 paul swed paulswedb@... writes:

 
  Chuck is correct I have done this trick on FRS units. The glass clears
 and
  the lamp re-ignites and continues to work for a long time. Actually it
  hasn't failed and this must be 2 years now.
  Regards
  Paul
  WB8TSL
 
  On Fri, Jun 20, 2014 at 8:34 AM, Chuck Harris cfharris@... wrote:
 
   Just in case you weren't aware, bad lamps can often be
   resurrected by the judicious application of heat.  The idea
   is to heat the bulb enough to evaporate all of the Rb
   that is deposited on the glass (making it black), and then
   let the lamp cool.   The Rb will again condense out on the
   glass, but this time it will condense out where the lamp
   is coolest, and will spare the rest of the bulb, allowing
   the light to get out.
  
   -Chuck Harris
  
  

 Chuck and Paul

 Do you have any more specific information on how to do this?

 I also have an FRK that has a lamp that is failing to run consistantly, and
 would like to try this to resurrect it.

 I am afraid of doing more harm than good without some good guidance.

 regards

 peter
 G0RSQ

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[time-nuts] dsPICs and GPSDOs

2014-06-20 Thread Bob Stewart
Once I got my TIC going, I suppose it was inevitable that I build a GPSDO with 
a dsPIC33.  I have a few dsPIC specific questions for anyone who designs with 
them.

1. VCAP.  The datasheet says that it should be a surface mount device.  I had 
hoped to avoid those.  Can I get away with a 10uf tantalum placed at  .1 from 
the pin?  I'm using a 28-pin DIP dsPIC, which will probably be socketed.


2. The datasheet suggests an inductor between AVDD and VDD.  Given that I'll 
only be reading the ADC twice a second (PPS and temps), can I just use the 
straight wire that I have already penned in?  I'm starting to run out of board 
space.

As to why I'm using a dsPIC: the one I chose has a number of features that suit 
me, such as 2 UARTs, SPI, buffered ADC, (audio) DAC, and especially relocatable 
pins.  To be honest, I don't know whether this will result in a general purpose 
GPSDO engine (with sawtooth correction) or a smoke machine, but I'm hoping for 
the best.  I'll try to resist the temptation to make more posts until I have a 
completed project.

Bob - AE6RV
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Re: [time-nuts] FE5680 GPS Disciplined Controller

2014-06-20 Thread Chris Albertson
Question:  Where is the source code for this project?  I hunted through
this thread but I was not able to find a link.

Also, that service linked to below is the best price I've seen.  99 cents
each.

On Wed, Jun 18, 2014 at 11:06 PM, David Hopkins dav...@bigpond.net.au
wrote:


 The service is excellent. It usually takes about 4 days to manufacture and
 they are then shipped by airmail.
 Have a look at :- http://imall.iteadstudio.com/
 open-pcb/pcb-prototyping.html

-- 

Chris Albertson
Redondo Beach, California
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[time-nuts] Sad news Ulrich Bangert

2014-06-20 Thread Hartmut Paesler

Dear group,

unfortunately I have to deliver the sad news that Ulrich Bangert, DF6JB
passed away on 11/06, aged 59.

Best regards,

Hartmut DL1YDD


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Re: [time-nuts] Sad news Ulrich Bangert

2014-06-20 Thread SAIDJACK
Wow,
 
that's a shock.
 
He was such a nice guy, always supporting requests for changes etc. Very  
sad. He was quite young as well!
 
Our condolences to his wife and family.
 
Said
 
 
In a message dated 6/20/2014 13:58:36 Pacific Daylight Time,  
timen...@paesler.de writes:


Dear  group,

unfortunately I have to deliver the sad news that Ulrich  Bangert, DF6JB
passed away on 11/06, aged 59.

Best  regards,

Hartmut  DL1YDD


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Re: [time-nuts] Sad news Ulrich Bangert

2014-06-20 Thread paul swed
Hartmut,
I did not know this and thank you for sharing.
I have read many of his articles and posts, he had a global reach.
Regards
Paul
WB8TSL



On Fri, Jun 20, 2014 at 4:52 PM, Hartmut Paesler timen...@paesler.de
wrote:


 Dear group,

 unfortunately I have to deliver the sad news that Ulrich Bangert, DF6JB
 passed away on 11/06, aged 59.

 Best regards,

 Hartmut DL1YDD


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Re: [time-nuts] Sad news Ulrich Bangert

2014-06-20 Thread Brooke Clarke

Hi:

That's unfortunate, he made a large contribution to Time Nuts and by extension 
to many.

Because I've been studying diet and nutrition for the past few months can 
someone tell me why he died?
I believe that the low fat diet that the U.S. has promoted and which has spread world wide is responsible for the 
premature deaths of millions of people.


Have Fun,

Brooke Clarke
http://www.PRC68.com
http://www.end2partygovernment.com/2012Issues.html
http://www.prc68.com/I/DietNutrition.html

Hartmut Paesler wrote:

Dear group,

unfortunately I have to deliver the sad news that Ulrich Bangert, DF6JB
passed away on 11/06, aged 59.

Best regards,

Hartmut DL1YDD


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Re: [time-nuts] Lamp for FRK Rubidium Needed

2014-06-20 Thread Chuck Harris

Paul's description is spot on.

A few of things to note:

1) The melting point of Rb is 39C (100F), so it
doesn't take a lot of heat to melt it... but it needs
to evaporate, which takes a little more.  Basically,
once it melts, the amount of Rb that can be made a gas
depends on the pressure in the bulb, and the temperature.
Once you reach the vapor pressure of Rb for the given
temperature you can't evaporate any more.

2) What you are trying to do is clear all of the excess
Rb that has plated out on the glass and move it as a metal
ball to somewhere it won't get in the way of the light
getting to the filter cell, and the detector.

3) I suspect the bulb is pyrex, but I am not sure of that,
I would suggest treating it like it wasn't.  Don't heat
it quickly, and don't let it cool quickly.  You don't
need to get anywhere near red heat.

To support the bulb, make yourself a loop of steel wire
that you can rest the bulb onto.  What you want is a
loop shaped like a lollipop.  Clamp the stem of the wire
loop in a vise, or something that will hold it.  Don't work
far above the ground, and it would be a good idea to have
a soft landing below the bulb just in case...  (If you had
50 bulbs I would bet that the little bugger would bounce
off of a cement floor without harm... But you have only
one, so count on it shattering...)

Once the bulb is clear, you are done.  The real truth is
once it is clearer than it was, it is going to work better
than it did... When it is all the way clear, it is a good
as it was when it was new, and  should last as long as a
new bulb would have.

-Chuck Harris

Peter wrote:



paul swed paulswedb@... writes:



Chuck is correct I have done this trick on FRS units. The glass clears and
the lamp re-ignites and continues to work for a long time. Actually it
hasn't failed and this must be 2 years now.
Regards
Paul
WB8TSL


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Re: [time-nuts] Sad news Ulrich Bangert

2014-06-20 Thread Tom Van Baak
Hi Hartmut,

Thanks for letting us know. Ulrich has been on this mailing list since the 
early days. He is one of several with his own web site (www.ulrich-bangert.de) 
and freely shared his designs, articles, and software tools with the world. He 
was a quality contributor to the list, and many of us also have lots of private 
emails from him over the years.

As Said already mentioned, please pass along condolences to his loved ones, on 
behalf of the group.

Thanks,
/tvb

- Original Message - 
From: Hartmut Paesler timen...@paesler.de
To: time-nuts@febo.com
Sent: Friday, June 20, 2014 1:52 PM
Subject: [time-nuts] Sad news Ulrich Bangert


 
 Dear group,
 
 unfortunately I have to deliver the sad news that Ulrich Bangert, DF6JB
 passed away on 11/06, aged 59.
 
 Best regards,
 
 Hartmut DL1YDD
 
 


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[time-nuts] FE5680 GPS Disciplined Controller

2014-06-20 Thread Mark Sims
Maybe...  maybe not.  Some of the Rb's store the tuning word in the processor 
EEPROM and those have a rather limited number of write cycles.   


You can change the DDS tuning words almost as many times per minute or per 
second as you wish to achieve the desired average accuracy. 
   
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Re: [time-nuts] Sad news Ulrich Bangert

2014-06-20 Thread John Miles
This is indeed terrible to hear.  Ulrich's free software contributions were
not only valuable in my work but useful to a lot of other people with test
gear.  He was also one of my first customers, putting a lot of faith in a
guy he'd never met who was selling PN analyzers out of his basement in
Seattle.  I'm sorry we never had the chance to get together in person.  He
was certainly one of the good guys!  

-- john, KE5FX
Miles Design LLC

 -Original Message-
 From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On
 Behalf Of Tom Van Baak
 Sent: Friday, June 20, 2014 3:13 PM
 To: Discussion of precise time and frequency measurement
 Cc: Hartmut Paesler
 Subject: Re: [time-nuts] Sad news Ulrich Bangert
 
 Hi Hartmut,
 
 Thanks for letting us know. Ulrich has been on this mailing list since the
early
 days...

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Re: [time-nuts] FE5680 GPS Disciplined Controller

2014-06-20 Thread Chris Albertson
I think the user FE5680  manual says you can change the tuning word as much
as you like.   But changing the EEPROM is different, that is used on power
up.  In a GPSDO you would likely want to send a command over the serial
interface when you need to make a change but you would only write to the
EEPROM as a special case, maybe if you wanted to place the Rb in a none GPS
mode so it could be portable.  I think you would store the power-on
defaults inside the GPSDO controller's uP.  Anyways changing the running
word and writing it to memory are different.

BTW I made a temperature controller for mine.   The unit is bolted to a
large heat sink and placed in a box with a fan.  The fan speed is
controlled by the heat sink temperature.  So it is an ovenized box that is
powered by waste heat.   My problem is finding a decent temperer sensor.
 I've tried several and they are noisy.

This version is simple.  The parts list is just three tab voltage
regulators, a power darlinton (for the fan motor) and an 8-pin AVR chip.
 The AVR uses one analog input to sense temperer and one analog output to
control the fan speed.The software is very simple.

Once I find a good temperature sensors I want to also measure the ambient
air temperature and control the fan based on the delta between the heat
sink and ambient.




On Fri, Jun 20, 2014 at 5:11 PM, Mark Sims hol...@hotmail.com wrote:

 Maybe...  maybe not.  Some of the Rb's store the tuning word in the
 processor EEPROM and those have a rather limited number of write cycles.

 
 You can change the DDS tuning words almost as many times per minute or per
 second as you wish to achieve the desired average accuracy.
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-- 

Chris Albertson
Redondo Beach, California
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Re: [time-nuts] FE5680 GPS Disciplined Controller

2014-06-20 Thread Peter Bell
I can't claim it's 100%, but all the ones I've seen that had the FEI logo
and the address silk-screened onto the metal case and a single adhesive
label with the serial number have been the old ones.  The new units have
two adhesive labels and no screen printing.  Note that this only seems to
work for the FE-5680A - I have also seen a FE-5680B that had the new type
electronics and was screen printed.

Has anyone on the list got one that doesn't follow this rule?

Regards,

Pete



On Thu, Jun 19, 2014 at 4:59 PM, Charles Steinmetz csteinm...@yandex.com
wrote:

 Bill wrote:

  There are two types of FE5680's.  The older style used an ANALOG approach
 to controlling the Rb.  The newer version changed the circuitry so that
 frequency control was done with a DDS device by means of sending a digital
 word to the DDS and thus changes frequency.  The digital version does not
 permit any ANALOG control.


 Instructions for determining which version one has would make it easier
 for potential users to decide if they want a controller.  Preferably,
 without opening it up or turning it on, if that is possible.  Can you tell
 by the label, for example?

 Best regards,

 Charles




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Re: [time-nuts] Sad news Ulrich Bangert

2014-06-20 Thread Poul-Henning Kamp
In message 53a49f22.5060...@paesler.de, Hartmut Paesler writes:

unfortunately I have to deliver the sad news that Ulrich Bangert, DF6JB
passed away on 11/06, aged 59.

He made the world a better place.

-- 
Poul-Henning Kamp   | UNIX since Zilog Zeus 3.20
p...@freebsd.org | TCP/IP since RFC 956
FreeBSD committer   | BSD since 4.3-tahoe
Never attribute to malice what can adequately be explained by incompetence.
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