Re: [time-nuts] Tbolt temperature Control

[WarrenS]

Neville

My responses to your well stated and mostly accurate 2c worth, 
even though much of it does not apply to this situation.

> I cannot remember the term in a PID equation that accounts for time delay.
Yea, pretty hard to remember, It called "Delay" on Smith predictor type of PID. 

Sounds like you also missed where I wrote "with a MODIFIED PID TYPE of S/W 
controller".

> Thermal control must face some nasty delay functions
Turns out for this application, a pretty basic type of PID works very well 
because the sensor 
has very high resolution and low noise, perfect for a large derivative term 
and the main temp TC is very slow and very dominate. 
No true delay going on just some slower faster Time constants that don't effect 
much.

 >It is the wrong algorithm for controlling almost any heater!
Probable get some disagreement from any OXCO manufacture on that.

> It is excellent for driving pens in pen recorders where mass,  ...
In fact a basic PID is not excellent for controlling much of anything, there 
are much better ways, 
BUT It can be adjusted to drive just about anything, which is one reason it is 
used so much.

>I would suggest controlling the air temperature around the case.
I agree that is the standard way and would work fine. 
However there are many advantages to heating  the case and using the internal 
sensor instead.
Some of which are Lower power, faster warm-up, less parts, it gets rid of that 
BIG delay TC you were referring to, 
does not need a fan, does not need a box, etc, etc.  
One of the things that makes the internal sensor control work 
so well is its better than 0.001 deg resolution.
  
>by  controlling the air temperature you will control the entire case of the 
>TBOLT. 
Not necessary so unless until you add your 'local tornado of air" Don't need 
that with the case heater.

> (controlling air temp) will have much faster response
You may want to re-think the way you said that statement because it is VERY 
wrong.

> Air controls the case of the OCXO, voltage regulators and not just the 
> temperature sensors.
In some situations controlling the internal temp sensor instead of  air or case 
temp will work better.
In this case it does not matter much, either are plenty good enough.
EXCEPT if the low resolution sensor is in the Tbolt like in all the new ones, 
in which case its better to keep the sensor constant so that 'Bad stuff' does 
nopt happen when it takes it giant steps.

> your best control algorithm uses the inverse transfer function of the thermal 
> system to predict a somewhat tardy response.
If you want simple and 'good enough', a simple PD works fine here.

Bottom line
You should try it, It's easy top assemble and  works good. If you need any help 
or have any problems with it let me know.

>  There, I have had my 2c worth, cheers, Neville Michie
Thanks, and Now I have had my 2c also, and double cheers to you

Have fun,
ws



"Neville Michie" namic...@gmail.com

> Hi,
> your problem should be to adjust to physical reality, then you may
> be able to control you TBOLT temperature.
> I cannot remember the term in a PID equation that accounts for time delay.
> In fact there is not one! It is the wrong algorithm for controlling almost 
> any heater!
> It is excellent for driving pens in pen recorders where mass,  velocity and 
> position
> are the terms.
> Thermal control must face some nasty delay functions, like Gauss's error 
> function.
> When the temperature error signal is delayed, as in the TBOLT, your best 
> control algorithm
> uses the inverse transfer function of the thermal system to predict a 
> somewhat tardy response.
> An alternative method that works very well is to create an isothermal  wall 
> around the TBOLT
> which is held at constant temperature. I would suggest your light  bulb and a 
> small
> computer fan to create a local tornado of air around the TBOLT and by  
> controlling the
> air temperature you will control the entire case of the TBOLT. This will have 
> much
> faster response and may control the case of the OCXO, voltage regulators and 
> not
> just the temperature sensors.
>  There, I have had my 2c worth,
> cheers, Neville Michie
> 
> 
> 
> 
> On 27/08/2009, at 5:56 AM, WarrenS wrote:
> 
>>
>> This can also be made to work on the TBolt units that have the 1/2  
>> deg course Temp sensor.
>> The control loop gets a bit trickier, but it can hold the Temp very  
>> close at one its course transitions points.
>> This would come in handy for those not wanting to change their  
>> sensor to the high resolution type.
>>
>> Another useful feature to add to a completely independent micro  
>> controller so that it needs no other inputs is to have its program  
>> smart enough to automatically and slowly readjust its set point  
>> control Temperature to just above the highest day to day Peak temp  
>> it sees. Needs no extra inputs, It just needs to monitor its own  
>> PID loop to see if it even comes out of control due

Re: [time-nuts] Tbolt temperature Control

[Neville Michie]

Hi,
your problem should be to adjust to physical reality, then you may
be able to control you TBOLT temperature.
I cannot remember the term in a PID equation that accounts for time  
delay.
In fact there is not one! It is the wrong algorithm for controlling  
almost any heater!
It is excellent for driving pens in pen recorders where mass,  
velocity and position

are the terms.
Thermal control must face some nasty delay functions, like Gauss's  
error function.
When the temperature error signal is delayed, as in the TBOLT, your  
best control algorithm
uses the inverse transfer function of the thermal system to predict a  
somewhat tardy response.
An alternative method that works very well is to create an isothermal  
wall around the TBOLT
which is held at constant temperature. I would suggest your light  
bulb and a small
computer fan to create a local tornado of air around the TBOLT and by  
controlling the
air temperature you will control the entire case of the TBOLT. This  
will have much
faster response and may control the case of the OCXO, voltage  
regulators and not

just the temperature sensors.
There, I have had my 2c worth,
cheers, Neville Michie




On 27/08/2009, at 5:56 AM, WarrenS wrote:



This can also be made to work on the TBolt units that have the 1/2  
deg course Temp sensor.
The control loop gets a bit trickier, but it can hold the Temp very  
close at one its course transitions points.
This would come in handy for those not wanting to change their  
sensor to the high resolution type.


Another useful feature to add to a completely independent micro  
controller so that it needs no other inputs is to have its program  
smart enough to automatically and slowly readjust its set point  
control Temperature to just above the highest day to day Peak temp  
it sees. Needs no extra inputs, It just needs to monitor its own  
PID loop to see if it even comes out of control due to excess temp.


Note you do not have to pass anything thru or output any RS232,  
just the ONE bit  if the micro is going to control the temp out bit.
It just needs to pick up the Tbolt output data in parallel and  
capture the Temp info.
If the micro is not doing the Temp control then there is no need to  
have the extra micro.


ws


Don Latham djl at montana.com
Wed Aug 26 17:38:21 UTC 2009


Heck, Warren, I'll put it on the line :-). Use a very simple and  
cheap
processor such as a Picaxe, pass the rs232 through it to Lady  
Heather etc,
and capture  the temperature, using it appropriately. Should work  
nicely
and keeps the temp control local. Even put a little LED on it to  
indicate

state.
Don

**

TBolt Nuts

To keep My TBolt's temperature constant so that the environment has
minimal effect on it,
I use an aquarium temperature controller (modified to have low  
hysteresis)
connected to a low wattage light bulb, placed in a box with the  
TBolt.
It works OK and keeps the TBolt's temperature constant to well  
under 1

deg.
To do it better and make it  more hi tech,
I'd like to have the temperature control based on the TBolt's  
internal

sensor.

What I have found works well is to use the TBolt's own RS232  
temperature

sensor output data,
and with a modified PID type of S/W controller, turn an external  
heater

&/or cooler on off.

The heater can be an appropriate power resistor or transistor  
dissipating

up to about 4 Watt,
mounted to the TBolt case. What I use to cool the Tbolt up to 5  
deg C, is

a small fan blowing
at a heatsink mounted on the top of the TBolt's case.
Turning the fan on & off with a S/W driven switch, can be used to  
keep the

TBolt's
internal temperature very constant over a limited external  
temperature

range.
A standard PC chip fan & heatsink may be OK, if it does not add Phase
noise due to it's vibration.

Because of the long time constant and slow response of the internal
temperature sensor,
a single digital on-off bit, updated at a max rate of once per second
works great for control,
No analog needed. To keep the hardware and interface circuit simple,
I'd like to be able to use one of the unused standard RS232 outputs,
such as RTS, CTS, DSR, DTR  as the heater/cooler control bit(s).
This is no problem when doing this in a DOS program or from an added
microprocessor
that monitors the Tbolt's  communications,  But the question is,
can it be done in Windows in such a way that a modified existing  
program

such as
Lady Heather or Tbolt monitor could control an already existing  
readily

available digital bit?

Being a control person, Doing a software algorithm is the easy part.
Making Windows do any kind of non standard I/O control, is way  
above my

capability.
I'd like to get feedback from a Windows expert if there is a  
simple way to

control an existing Digital bit
that would be available on a PC being used in a typical setup that  
is used

to monitor the Tbolt.
One way I have heard suggested is to use the sound card output,
but I'd like to keep it

Re: [time-nuts] Couple of questions for Racal 1992 owners

[Ed Palmer]

My 1992 has a similarly ugly reference output - until I terminate it.  
Then it's a fairly nice square wave between 0 and 1 volt.  Rise & fall 
times are in the range of 5 ns.  The manual doesn't state what the wave 
shape is, only that it's > 600 mVp-p into 50 ohms. I have a brochure 
that says "TTL levels giving approx. 1Vp-p into 50 ohms".  My phase 
measurements also have a similar amount of 'noise' to yours.


Which timebase does yours have?  I've got option 4E (similar to 4B).  
Although the timebase appears to be stable, I've noticed that the 
counter drifts about 5e-9 during warmup, even when the oscillator has 
been on standby for many days.  It takes a couple of hours to settle 
down.  Does yours do anything similar?


Ed

John Green wrote:

Just acquired a used 1992 off eBay. Excellent, almost like new with manual
and even spare fuses. I noticed that the internal reference's waveform is
more like a nasty sawtooth than a nice sine wave. Is that normal? Also, when
I hook my GPSDO through a two way splitter and two different length cables
and measure phase, I get a +\- 3 LSD ambiguity. Is that about right?
___
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.
  


___
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.

Re: [time-nuts] Tbolt temperature Control

[Lux, Jim (337C)]

I use the  System.IO.Ports.SerialPort.RtsEnable property

If you're doing input (e.g. looking for a 1pps), I would imagine you'd use the 
PinChangedEvent.  I haven't tried it or looked at the timing.

These exist in all .NET frameworks from 2.0 onwards.


If you want to use the Windows API directly, EscapeCommFunction(hFile,SETRTS) 
would presumably work.

James Lux, P.E.
Task Manager, SOMD Software Defined Radios
Flight Communications Systems Section 
Jet Propulsion Laboratory
4800 Oak Grove Drive, Mail Stop 161-213
Pasadena, CA, 91109
+1(818)354-2075 phone
+1(818)393-6875 fax

> -Original Message-
> From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On
> Behalf Of Scott Newell
> Sent: Wednesday, August 26, 2009 1:48 PM
> To: Discussion of precise time and frequency measurement
> Subject: Re: [time-nuts] Tbolt temperature Control
> 
> At 03:34 PM 8/26/2009 , Mark Sims wrote:
> >
> >
> >The problem is with the Windows code.  I don't know how to reliably
> control the modem signals under Windows... perhaps John Miles would
> know.
> Most Windows users use USB-
> 
> EscapeCommFunction()?
> 
> 
> 
> ___
> 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.

___
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.

Re: [time-nuts] Tbolt temperature Control

[Scott Newell]

At 03:34 PM 8/26/2009 , Mark Sims wrote:
>
>
>The problem is with the Windows code.  I don't know how to reliably
control the modem signals under Windows... perhaps John Miles would know.
Most Windows users use USB-

EscapeCommFunction()?



___
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.

Re: [time-nuts] Tbolt temperature Control

[Lux, Jim (337C)]

> -Original Message-
> From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On
> Behalf Of Mark Sims
> Sent: Wednesday, August 26, 2009 1:35 PM
> To: time-nuts@febo.com
> Subject: [time-nuts] Tbolt temperature Control
> 
> 
> Putting the PID stuff into Lady Heather is no problem (if you write the
> algorithm).  It would be pretty trivial to drop it into the DOS
> version.  It would be best if a single control line would either heat
> or cool (no OFF state).  Even simpler,  keep the fan stirring the air
> all the time.  Apply heat when needed.
> 
> The problem is with the Windows code.  I don't know how to reliably
> control the modem signals under Windows... perhaps John Miles would
> know.   Most Windows users use USB-RS232 converters and these are
> infamous for their flakey control signals.

Which Windows? Or more properly, which flavor of .NET?  I've had fairly good 
luck with the later .NET incarnations (>=2) even with USB/Serial dongles.

___
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.

[time-nuts] Tbolt temperature Control

[Mark Sims]

Putting the PID stuff into Lady Heather is no problem (if you write the 
algorithm).  It would be pretty trivial to drop it into the DOS version.  It 
would be best if a single control line would either heat or cool (no OFF 
state).  Even simpler,  keep the fan stirring the air all the time.  Apply heat 
when needed.

The problem is with the Windows code.  I don't know how to reliably control the 
modem signals under Windows... perhaps John Miles would know.   Most Windows 
users use USB-RS232 converters and these are infamous for their flakey control 
signals.

I think the most reliable way would be a small micro that monitored the TSIP 
strings from the Tbolt and picked off the message that has the temperature 
field.  Ideally a Peltier device driven by an H bridge motor controller would 
control the heating and cooling.

By insulating the Tbolt in a foil covered cardboard box,  you should be able to 
keep the a/c and heating induced temperature swings under 0.1C.  It is these 
short term swings that the Tbolt seems most sensitive to.




_
Hotmail® is up to 70% faster. Now good news travels really fast. 
http://windowslive.com/online/hotmail?ocid=PID23391::T:WLMTAGL:ON:WL:en-US:WM_HYGN_faster:082009
___
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.

[time-nuts] Couple of questions for Racal 1992 owners

[John Green]

Just acquired a used 1992 off eBay. Excellent, almost like new with manual
and even spare fuses. I noticed that the internal reference's waveform is
more like a nasty sawtooth than a nice sine wave. Is that normal? Also, when
I hook my GPSDO through a two way splitter and two different length cables
and measure phase, I get a +\- 3 LSD ambiguity. Is that about right?
___
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.

Re: [time-nuts] Tbolt temperature Control

[WarrenS]

This can also be made to work on the TBolt units that have the 1/2 deg course 
Temp sensor. 
The control loop gets a bit trickier, but it can hold the Temp very close at 
one its course transitions points. 
This would come in handy for those not wanting to change their sensor to the 
high resolution type.

Another useful feature to add to a completely independent micro controller so 
that it needs no other inputs is to have its program smart enough to 
automatically and slowly readjust its set point control Temperature to just 
above the highest day to day Peak temp it sees. Needs no extra inputs, It just 
needs to monitor its own PID loop to see if it even comes out of control due to 
excess temp.  

Note you do not have to pass anything thru or output any RS232, just the ONE 
bit  if the micro is going to control the temp out bit.
It just needs to pick up the Tbolt output data in parallel and capture the Temp 
info.
If the micro is not doing the Temp control then there is no need to have the 
extra micro.

ws

>Don Latham djl at montana.com 
>Wed Aug 26 17:38:21 UTC 2009 

>Heck, Warren, I'll put it on the line :-). Use a very simple and cheap
>processor such as a Picaxe, pass the rs232 through it to Lady Heather etc,
>and capture  the temperature, using it appropriately. Should work nicely
>and keeps the temp control local. Even put a little LED on it to indicate
>state.
>Don
**
> TBolt Nuts
>
> To keep My TBolt's temperature constant so that the environment has
> minimal effect on it,
> I use an aquarium temperature controller (modified to have low hysteresis)
> connected to a low wattage light bulb, placed in a box with the TBolt.
> It works OK and keeps the TBolt's temperature constant to well under 1
> deg.
> To do it better and make it  more hi tech,
> I'd like to have the temperature control based on the TBolt's internal
> sensor.
>
> What I have found works well is to use the TBolt's own RS232 temperature
> sensor output data,
> and with a modified PID type of S/W controller, turn an external heater
> &/or cooler on off.
>
> The heater can be an appropriate power resistor or transistor dissipating
> up to about 4 Watt,
> mounted to the TBolt case. What I use to cool the Tbolt up to 5 deg C, is
> a small fan blowing
> at a heatsink mounted on the top of the TBolt's case.
> Turning the fan on & off with a S/W driven switch, can be used to keep the
> TBolt's
> internal temperature very constant over a limited external temperature
> range.
> A standard PC chip fan & heatsink may be OK, if it does not add Phase
> noise due to it's vibration.
>
> Because of the long time constant and slow response of the internal
> temperature sensor,
> a single digital on-off bit, updated at a max rate of once per second
> works great for control,
> No analog needed. To keep the hardware and interface circuit simple,
> I'd like to be able to use one of the unused standard RS232 outputs,
> such as RTS, CTS, DSR, DTR  as the heater/cooler control bit(s).
> This is no problem when doing this in a DOS program or from an added
> microprocessor
> that monitors the Tbolt's  communications,  But the question is,
> can it be done in Windows in such a way that a modified existing program
> such as
> Lady Heather or Tbolt monitor could control an already existing readily
> available digital bit?
>
> Being a control person, Doing a software algorithm is the easy part.
> Making Windows do any kind of non standard I/O control, is way above my
> capability.
> I'd like to get feedback from a Windows expert if there is a simple way to
> control an existing Digital bit
> that would be available on a PC being used in a typical setup that is used
> to monitor the Tbolt.
> One way I have heard suggested is to use the sound card output,
> but I'd like to keep it even simpler than that, Any suggestions?
>
> If anyone is interested in developing a program to make an existing stand
> alone micro
> or basic stamp to include this function they can contact me off line for
> some sugestions.
>
> Thanks,
> ws
> **


___
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.

Re: [time-nuts] Tbolt temperature Control

[WarrenS]

Another useful feature to add to a completely independent micro controller so 
that it needs no other inputs is to have its program smart enough to 
automatically and slowly readjust its set point control Temperature to just 
above the highest day to day Peak temp it sees. Needs no extra inputs, It just 
needs to monitor its own PID loop to see if it even comes out of control due to 
excess temp.  

warren Wrote:
Note you do not have to pass anything thru or output any RS232, just the ONE 
bit  if the micro is going to control the temp out bit.
It just needs to pick up the Tbolt output data in parallel and capture the Temp 
info.
If the micro is not doing the Temp control then there is no need to have the 
extra micro.

ws


Don Latham djl at montana.com 
Wed Aug 26 17:38:21 UTC 2009 

  a.. Previous message: [time-nuts] Tbolt temperature Control 
  b.. Next message: [time-nuts] Tbolt temperature Control 
  c.. Messages sorted by: [ date ] [ thread ] [ subject ] [ author ] 



Heck, Warren, I'll put it on the line :-). Use a very simple and cheap
processor such as a Picaxe, pass the rs232 through it to Lady Heather etc,
and capture  the temperature, using it appropriately. Should work nicely
and keeps the temp control local. Even put a little LED on it to indicate
state.
Don

WarrenS
> TBolt Nuts
>
> To keep My TBolt's temperature constant so that the environment has
> minimal effect on it,
> I use an aquarium temperature controller (modified to have low hysteresis)
> connected to a low wattage light bulb, placed in a box with the TBolt.
> It works OK and keeps the TBolt's temperature constant to well under 1
> deg.
> To do it better and make it  more hi tech,
> I'd like to have the temperature control based on the TBolt's internal
> sensor.
>
> What I have found works well is to use the TBolt's own RS232 temperature
> sensor output data,
> and with a modified PID type of S/W controller, turn an external heater
> &/or cooler on off.
>
> The heater can be an appropriate power resistor or transistor dissipating
> up to about 4 Watt,
> mounted to the TBolt case. What I use to cool the Tbolt up to 5 deg C, is
> a small fan blowing
> at a heatsink mounted on the top of the TBolt's case.
> Turning the fan on & off with a S/W driven switch, can be used to keep the
> TBolt's
> internal temperature very constant over a limited external temperature
> range.
> A standard PC chip fan & heatsink may be OK, if it does not add Phase
> noise due to it's vibration.
>
> Because of the long time constant and slow response of the internal
> temperature sensor,
> a single digital on-off bit, updated at a max rate of once per second
> works great for control,
> No analog needed. To keep the hardware and interface circuit simple,
> I'd like to be able to use one of the unused standard RS232 outputs,
> such as RTS, CTS, DSR, DTR  as the heater/cooler control bit(s).
> This is no problem when doing this in a DOS program or from an added
> microprocessor
> that monitors the Tbolt's  communications,  But the question is,
> can it be done in Windows in such a way that a modified existing program
> such as
> Lady Heather or Tbolt monitor could control an already existing readily
> available digital bit?
>
> Being a control person, Doing a software algorithm is the easy part.
> Making Windows do any kind of non standard I/O control, is way above my
> capability.
> I'd like to get feedback from a Windows expert if there is a simple way to
> control an existing Digital bit
> that would be available on a PC being used in a typical setup that is used
> to monitor the Tbolt.
> One way I have heard suggested is to use the sound card output,
> but I'd like to keep it even simpler than that, Any suggestions?
>
> If anyone is interested in developing a program to make an existing stand
> alone micro
> or basic stamp to include this function they can contact me off line for
> some sugestions.
>
> Thanks,
> ws
> **
>
>
>
> ___
> time-nuts mailing list -- time-nuts at febo.com
> To unsubscribe, go to
> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
> and follow the instructions there.
>


-- 
Dr. Don Latham AJ7LL
Six Mile Systems LLP
17850 Six Mile Road
POB 134
Huson, MT, 59846
VOX 406-626-4304
www.lightningforensics.com
www.sixmilesystems.com




___
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.

Re: [time-nuts] Tbolt temperature Control

[WarrenS]

Note you do not have to pass anything thru or output any RS232, just the ONE 
bit  if the micro is going to control the temp out bit.
It just needs to pick up the Tbolt output data in parallel and capture the Temp 
info.
If the micro is not doing the Temp control then there is no need to have the 
extra micro.

ws

Don Latham  said:
Heck, Warren, I'll put it on the line :-). Use a very simple and cheap
processor such as a Picaxe, pass the rs232 through it to Lady Heather etc,
and capture  the temperature, using it appropriately. Should work nicely
and keeps the temp control local. Even put a little LED on it to indicate
state.
Don

WarrenS
> TBolt Nuts
>
> To keep My TBolt's temperature constant so that the environment has
> minimal effect on it,
> I use an aquarium temperature controller (modified to have low hysteresis)
> connected to a low wattage light bulb, placed in a box with the TBolt.
> It works OK and keeps the TBolt's temperature constant to well under 1
> deg.
> To do it better and make it  more hi tech,
> I'd like to have the temperature control based on the TBolt's internal
> sensor.
>
> What I have found works well is to use the TBolt's own RS232 temperature
> sensor output data,
> and with a modified PID type of S/W controller, turn an external heater
> &/or cooler on off.
>
> The heater can be an appropriate power resistor or transistor dissipating
> up to about 4 Watt,
> mounted to the TBolt case. What I use to cool the Tbolt up to 5 deg C, is
> a small fan blowing
> at a heatsink mounted on the top of the TBolt's case.
> Turning the fan on & off with a S/W driven switch, can be used to keep the
> TBolt's
> internal temperature very constant over a limited external temperature
> range.
> A standard PC chip fan & heatsink may be OK, if it does not add Phase
> noise due to it's vibration.
>
> Because of the long time constant and slow response of the internal
> temperature sensor,
> a single digital on-off bit, updated at a max rate of once per second
> works great for control,
> No analog needed. To keep the hardware and interface circuit simple,
> I'd like to be able to use one of the unused standard RS232 outputs,
> such as RTS, CTS, DSR, DTR  as the heater/cooler control bit(s).
> This is no problem when doing this in a DOS program or from an added
> microprocessor
> that monitors the Tbolt's  communications,  But the question is,
> can it be done in Windows in such a way that a modified existing program
> such as
> Lady Heather or Tbolt monitor could control an already existing readily
> available digital bit?
>
> Being a control person, Doing a software algorithm is the easy part.
> Making Windows do any kind of non standard I/O control, is way above my
> capability.
> I'd like to get feedback from a Windows expert if there is a simple way to
> control an existing Digital bit
> that would be available on a PC being used in a typical setup that is used
> to monitor the Tbolt.
> One way I have heard suggested is to use the sound card output,
> but I'd like to keep it even simpler than that, Any suggestions?
>
> If anyone is interested in developing a program to make an existing stand
> alone micro
> or basic stamp to include this function they can contact me off line for
> some sugestions.
>
> Thanks,
> ws
> **
>

___
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.

Re: [time-nuts] Tbolt temperature Control

[Don Latham]

Heck, Warren, I'll put it on the line :-). Use a very simple and cheap
processor such as a Picaxe, pass the rs232 through it to Lady Heather etc,
and capture  the temperature, using it appropriately. Should work nicely
and keeps the temp control local. Even put a little LED on it to indicate
state.
Don

WarrenS
> TBolt Nuts
>
> To keep My TBolt's temperature constant so that the environment has
> minimal effect on it,
> I use an aquarium temperature controller (modified to have low hysteresis)
> connected to a low wattage light bulb, placed in a box with the TBolt.
> It works OK and keeps the TBolt's temperature constant to well under 1
> deg.
> To do it better and make it  more hi tech,
> I'd like to have the temperature control based on the TBolt's internal
> sensor.
>
> What I have found works well is to use the TBolt's own RS232 temperature
> sensor output data,
> and with a modified PID type of S/W controller, turn an external heater
> &/or cooler on off.
>
> The heater can be an appropriate power resistor or transistor dissipating
> up to about 4 Watt,
> mounted to the TBolt case. What I use to cool the Tbolt up to 5 deg C, is
> a small fan blowing
> at a heatsink mounted on the top of the TBolt's case.
> Turning the fan on & off with a S/W driven switch, can be used to keep the
> TBolt's
> internal temperature very constant over a limited external temperature
> range.
> A standard PC chip fan & heatsink may be OK, if it does not add Phase
> noise due to it's vibration.
>
> Because of the long time constant and slow response of the internal
> temperature sensor,
> a single digital on-off bit, updated at a max rate of once per second
> works great for control,
> No analog needed. To keep the hardware and interface circuit simple,
> I'd like to be able to use one of the unused standard RS232 outputs,
> such as RTS, CTS, DSR, DTR  as the heater/cooler control bit(s).
> This is no problem when doing this in a DOS program or from an added
> microprocessor
> that monitors the Tbolt's  communications,  But the question is,
> can it be done in Windows in such a way that a modified existing program
> such as
> Lady Heather or Tbolt monitor could control an already existing readily
> available digital bit?
>
> Being a control person, Doing a software algorithm is the easy part.
> Making Windows do any kind of non standard I/O control, is way above my
> capability.
> I'd like to get feedback from a Windows expert if there is a simple way to
> control an existing Digital bit
> that would be available on a PC being used in a typical setup that is used
> to monitor the Tbolt.
> One way I have heard suggested is to use the sound card output,
> but I'd like to keep it even simpler than that, Any suggestions?
>
> If anyone is interested in developing a program to make an existing stand
> alone micro
> or basic stamp to include this function they can contact me off line for
> some sugestions.
>
> Thanks,
> ws
> **
>
>
>
> ___
> 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.
>


-- 
Dr. Don Latham AJ7LL
Six Mile Systems LLP
17850 Six Mile Road
POB 134
Huson, MT, 59846
VOX 406-626-4304
www.lightningforensics.com
www.sixmilesystems.com


___
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.

[time-nuts] Tbolt temperature Control

[WarrenS]

TBolt Nuts

To keep My TBolt's temperature constant so that the environment has minimal 
effect on it, 
I use an aquarium temperature controller (modified to have low hysteresis) 
connected to a low wattage light bulb, placed in a box with the TBolt. 
It works OK and keeps the TBolt's temperature constant to well under 1 deg.
To do it better and make it  more hi tech,  
I'd like to have the temperature control based on the TBolt's internal sensor.

What I have found works well is to use the TBolt's own RS232 temperature sensor 
output data, 
and with a modified PID type of S/W controller, turn an external heater &/or 
cooler on off.

The heater can be an appropriate power resistor or transistor dissipating up to 
about 4 Watt, 
mounted to the TBolt case. What I use to cool the Tbolt up to 5 deg C, is a 
small fan blowing 
at a heatsink mounted on the top of the TBolt's case. 
Turning the fan on & off with a S/W driven switch, can be used to keep the 
TBolt's 
internal temperature very constant over a limited external temperature range. 
A standard PC chip fan & heatsink may be OK, if it does not add Phase noise due 
to it's vibration.

Because of the long time constant and slow response of the internal temperature 
sensor, 
a single digital on-off bit, updated at a max rate of once per second works 
great for control, 
No analog needed. To keep the hardware and interface circuit simple, 
I'd like to be able to use one of the unused standard RS232 outputs, 
such as RTS, CTS, DSR, DTR  as the heater/cooler control bit(s).
This is no problem when doing this in a DOS program or from an added 
microprocessor 
that monitors the Tbolt's  communications,  But the question is, 
can it be done in Windows in such a way that a modified existing program such 
as 
Lady Heather or Tbolt monitor could control an already existing readily 
available digital bit? 

Being a control person, Doing a software algorithm is the easy part. 
Making Windows do any kind of non standard I/O control, is way above my 
capability. 
I'd like to get feedback from a Windows expert if there is a simple way to 
control an existing Digital bit 
that would be available on a PC being used in a typical setup that is used to 
monitor the Tbolt. 
One way I have heard suggested is to use the sound card output, 
but I'd like to keep it even simpler than that, Any suggestions?

If anyone is interested in developing a program to make an existing stand alone 
micro 
or basic stamp to include this function they can contact me off line for some 
sugestions.
  
Thanks,
ws
**



___
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.

[time-nuts] Service manual / schematics HP 5334A`

[Borislav Diviziev]

Hello everyone,

 

Can you, please, help me with finding a service manual and schematics of the
HP counter 5334A. On the Agilent site I can find the 5334B but I know there
are quite some differences between both.

 

Any info would be appreciated.

 

Thanks,

bdivi-at-hotmail.com

 

 

___
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.

[time-nuts] 58540A, anyone ?

[Marco IK1ODO -2]

Hi all,

anyone here has an HP 54540A for sale?

Answers to ik1...@spin-it.com

73 - Marco IK1ODO


___
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.

Re: [time-nuts] Time security query

[Javier Serrano]

When something goes wrong in an accelerator, like an unsolicited beam dump,
the timing system broadcasts a Post Mortem event (message) and lots of
equipment push diagnostics data with time tags up to the Post Mortem system
for analysis. These PLCs control things like Cryogenics, and other
industrial-like systems, and are very removed from what we do in the timing
team. I suppose they run a simplified NTP client, because NTP is not
considered critical for their mission and they don't have much memory or
time to devote to this. Your proposal of using a dedicated NTP server to
monitor the PLCs looks interesting, I'll look into it. Tagging PPS could be
risky as you say, maybe tagging something like a 0.1 Hz pulse train would be
better. We could then trigger an alarm as soon as the time tags are off by
one second.

On Wed, Aug 26, 2009 at 12:43 AM, Hal Murray wrote:

>
> javier.serrano.par...@gmail.com said:
> > There are some exceptions to this, with PLCs and other pieces of
> > hardware getting sync from NTP. We've had problems in our Post Mortem
> > system in the past, with a PLC not receiving NTP traffic because of
> > router misconfiguration and this resulting in incoherent time tags.
>
> Are your PLCs running full NTP or some minimal implementation?
>
> The reference implementation has a lot of monitoring/debugging options.
> Probably the simplest approach is to setup a ntp server and use it to
> monitor
> the systems you are interested in.  (I'll say more if anybody wants.)
>
> Speaking of software bugs, many of the minimal implementations have
> "interesting" problems.  In case anybody isn't familiar with it, Dave
> Plonka
> has a wonderful writeup of the Netgear/Univ-Wisc mixup.  I'd call it
> required
> reading for any computer science program.
>  
> http://pages.cs.wisc.edu/~plonka/netgear-sntp/
> Wikipedia has a page that covers a few more incidents:
>  http://en.wikipedia.org/wiki/NTP_server_misuse_and_abuse
>
> Anyway, if you are using ntp, add denial-of-service to the list of
> considerations, either on your servers or the servers you are using.  For
> popular servers like the ones run by NIST, there are significant errors
> during the normal daily peak load times.
>
>
> > Our proposed solution for that is to feed a PPS from one of our timing
> > receivers to the critical PLCs and ask them to time-tag it with their
> > internal NTP-derived time base.
>
> Is tagging a PPS enough?  How do you know if you are off by several
> seconds?
>
>
>
> --
> These are my opinions, not necessarily my employer's.  I hate spam.
>
>
>
>
> ___
> 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.
>
___
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.