Date   
Re: OT: I/V curve tracing made easy with Python and PyVISA

Albert Otten
 

Hi Tony,

Your 2465 doesn't have RS232, so you need a GPIB connection. Do you have such already (NI GPIB-USB-HS, Prologix,...)? I have the NI adapter. Or are you considering to use an Arduino (mentioned in your 2465 topic) for this? I know nothing of Arduinos (except that my son is married with these tiny things).
Tektronix had it's own version of NI-VISA, TekVISA, and a program Wavestar. These could be downloaded for free I think for Windows. I tried this once without much success and deleted it right away: together with NI drivers a HUGE amount of software! I used Linux ever since with the linux-gpib driver package. I don't know if the GPIB programs by Hakan (http://www.hakanh.com/dl/index.htm) together with drivers can serve you.
In my opinion PiVISA is not of much interest for you. VISA is intended for equipment that understands VISA commands. So you have to lookup in the Opt.10 manual which commands are recognized by the 2465 and send these commands exactly as shown in the manual. I have the same situation with my 7854 and CSAs.
At this moment I don't remember for sure whether drivers are still needed if the Pivisa-py package is used, but I think the are. If not then PiVISA is attractive. (Magnus knows?)
An alternative to PiVISA is to use the python package gpib_ctypes in combination with the Linux linux-gpib package or the (Linux, Windows) NI drivers.
The python script could look like this (note, I didn't test this since some time, I hope I removed errors):

#!/usr/bin/python3

# test gpib connection with the CSA803
from gpib_ctypes import gpib
# in my case, the CSA was set address to 1
csa=gpib.dev(0,1) # get device handle
print("device handle",csa) # was 17
print("status serial poll",gpib.serial_poll(csa))
# serial poll seems needed as first command as response to SRQ request issued by CSA at startup

gpib.write(csa,b'ID?') # no \r\n needed, EOI takes care of this
# in interactive mode the command also receives and prints the status byte, 8448.
result=gpib.read(csa,1000) # read ID and store in result
print(result)

# another example
gpib.write(csa,b'uptime?')
print(gpib.read(csa,1000)) # result immediately shown now
gpib.close(csa)

The DMM Opt.1 recognizes some additional GPIB commands.

Pffff,
Albert

On Fri, May 17, 2019 at 06:24 PM, Tony Fleming wrote:


Magnus, and most or all of you are in a "stratosphere" compared to me, who
is trying to learn my Tektronix 2465 DMS! But I also have P6407 and I would
like to learn how to use it.
Can anyone out there help me with something simple I can try to connect it?
I never have anything like this before, so use very simple terms what all I
need please.
You all were very helpful with my scope, when it was sick and now it works,
thanks to you all. I found this group to be the most helpful group out
there!
Thank you very much.
Tony

Re: IMPORTANT: Photos are eating up our storage

Siggi
 

On Fri, May 17, 2019 at 3:40 PM Carsten Bormann <cabocabo@...> wrote:

On May 17, 2019, at 21:01, Dale H. Cook <bridgewaterma@...>
wrote:

What went wrong is that images are using up too much storage.
They aren’t. They might be, at some point in the future, if the amount
used grows faster than the amount permitted by groups.io does. We don’t
know that yet.

Is anyone here willing to pony up $6,000.00 per year to pay for the next
level of storage?

Of course not. I don’t think the $2200/yr ($1100/yr for non-profits)
groups.io tier was meant for us. It will be interesting to see whether
groups.io will be able to expand the value received for our current
$110/yr to include more than 20 cents in storage.
I submitted a query to the groups.io support to ask about incremental
storage pricing. I don't think doubling the annual fee would be
prohibitive. Generally cloud storage costs are trending sharply downwards,
and so in a year or two I'd bet doubling the fee would pay for quadruple
the storage or so...

Re: OT: I/V curve tracing made easy with Python and PyVISA

Tony Fleming
 

Thank you Albert for your nice reply!
Yes, I have options 1,9,10+GPIB on my 2465 DMS scope. I also have DMM
option on top of the scope!
I purchased couple weeks ago the P6407 stuff, but it has no manual or any
instructions - I must find that information and print it....
I'm not planing to use it for anything serious, just to demo the Tektronix
scope and the "old technology", when I do shows or visit clubs/libraries....
Many people find older stuff interesting and the kids in the schools do not
learn almost any history in electronics!
I also have couple older scopes, like Simpson Model 466 - Handiscope, not
oscilloscope.... but it is interesting to see peoples reaction when they
see it in person.
One of my dream was to have Tektronix and some kind of "old scope" that is
as old as I'm now! ha ha ha
About Arduino - it is lots of fun and now we are using Python also and or
ESP8266 or ESP32 - for few bucks you have input-output + sensors or Wi-Fi
.... You should have your son demo stuff for you!
I wish I had a dad like you, who is in electronics and "plugged in".... but
I had Mr. Helebrand who was like the perfect dad but teach me electronics!
(Back in early 70's)
Anyway, if you, or anyone else, find the software and instructions+manuals
.... I appreciate your input and help guys/gals!
Thank you all!

On Fri, May 17, 2019 at 3:02 PM Albert Otten <aodiversen@...> wrote:

Hi Tony,

Your 2465 doesn't have RS232, so you need a GPIB connection. Do you have
such already (NI GPIB-USB-HS, Prologix,...)? I have the NI adapter. Or are
you considering to use an Arduino (mentioned in your 2465 topic) for this?
I know nothing of Arduinos (except that my son is married with these tiny
things).
Tektronix had it's own version of NI-VISA, TekVISA, and a program
Wavestar. These could be downloaded for free I think for Windows. I tried
this once without much success and deleted it right away: together with NI
drivers a HUGE amount of software! I used Linux ever since with the
linux-gpib driver package. I don't know if the GPIB programs by Hakan (
http://www.hakanh.com/dl/index.htm) together with drivers can serve you.
In my opinion PiVISA is not of much interest for you. VISA is intended for
equipment that understands VISA commands. So you have to lookup in the
Opt.10 manual which commands are recognized by the 2465 and send these
commands exactly as shown in the manual. I have the same situation with my
7854 and CSAs.
At this moment I don't remember for sure whether drivers are still needed
if the Pivisa-py package is used, but I think the are. If not then PiVISA
is attractive. (Magnus knows?)
An alternative to PiVISA is to use the python package gpib_ctypes in
combination with the Linux linux-gpib package or the (Linux, Windows) NI
drivers.
The python script could look like this (note, I didn't test this since
some time, I hope I removed errors):

#!/usr/bin/python3

# test gpib connection with the CSA803
from gpib_ctypes import gpib
# in my case, the CSA was set address to 1
csa=gpib.dev(0,1) # get device handle
print("device handle",csa) # was 17
print("status serial poll",gpib.serial_poll(csa))
# serial poll seems needed as first command as response to SRQ request
issued by CSA at startup

gpib.write(csa,b'ID?') # no \r\n needed, EOI takes care of this
# in interactive mode the command also receives and prints the
status byte, 8448.
result=gpib.read(csa,1000) # read ID and store in result
print(result)

# another example
gpib.write(csa,b'uptime?')
print(gpib.read(csa,1000)) # result immediately shown now
gpib.close(csa)

The DMM Opt.1 recognizes some additional GPIB commands.

Pffff,
Albert

On Fri, May 17, 2019 at 06:24 PM, Tony Fleming wrote:


Magnus, and most or all of you are in a "stratosphere" compared to me,
who
is trying to learn my Tektronix 2465 DMS! But I also have P6407 and I
would
like to learn how to use it.
Can anyone out there help me with something simple I can try to connect
it?
I never have anything like this before, so use very simple terms what
all I
need please.
You all were very helpful with my scope, when it was sick and now it
works,
thanks to you all. I found this group to be the most helpful group out
there!
Thank you very much.
Tony


Re: IMPORTANT: Photos are eating up our storage

Dave Voorhis
 

On 17 May 2019, at 21:09, Siggi <siggi@...> wrote:

I submitted a query to the groups.io support to ask about incremental
storage pricing. I don't think doubling the annual fee would be
prohibitive. Generally cloud storage costs are trending sharply downwards,
and so in a year or two I'd bet doubling the fee would pay for quadruple
the storage or so…
That is eminently reasonable, though I think another reasonable approach would be to switch to a Web-based forum, which would offer a number of advantages — multiple sub-forums, multiple parallel threads, easy archives, pictures embedded in messages, formatted text, possibility of advertising-based funding, eliminate the problem of context-free messages due to elided quotes — along with likely costing less for much more storage.

The downsides are less convenience or more difficult access for some users and a bit more IT effort and knowledge needed to maintain it.

Re: IMPORTANT: Photos are eating up our storage

EJP
 

Put them in the message.
Absolutely not.
I'm delighted to find that I'm wrong about that, and that the Web interface for groups.io preserves pictures in messages, but in that case putting them in the message is no better than putting them in the photos section. They still occupy space.

Can I also point out that when talking about the current growth rate we should not assume it is linear. One would or ally expect it to be exponential.

EJP

Re: OT: I/V curve tracing made easy with Python and PyVISA

Harvey White
 

On 5/17/2019 11:48 AM, magnustoelle via Groups.Io wrote:
Good Day,

thank you for your kind comments, Gentlemen. And thank you for that weblink and the German figure of speech, Albert! :-)

The trouble is that I am looking at my Keithley 230 programmable voltage source and the Keithley type 195 DMM (with its 100pA resolution)  at the shelves right behind my back right now. Both are equipped with GPIB, but I have never done much with either device yet - and they keep staring at me.
Looking at this from a programming standpoint, you have (generally) measuring equipment and stimulus equipment.  Changing the any of the above that you don't have support for is a matter of looking at what you've told device A (which you have) what to do.  You don't want to know how you told it to do that, that's possibly specific to the instrument (depending on age).  Then you need to look at what you want device B to do.  You compare ranges and functions, and assuming you can live with what device "B" does....

You replace the specific instructions of device A with the specific instructions of device B.

For maximum utility, you devise a switch of some sort (programming switch, very much depends on the language how you do it), so that given choice 1, you produce instructions for device A, and for choice 2, you produce instructions for device B.

In C, C++, this can be done with #define, and #ifdef statements. In basic (haven't used it for years.... likely an "on...... value" statement.  For pascal, you use the case statement unless your version of pascal has the equivalent of #define.

The difference between #define related stuff and case/switch/on stuff is that the former contains only the code you want, and cannot do anything else unless you recompile it.  It is, however, smaller in size.

The latter has all the options, and makes the choice on the fly. You have unused code (for the nonce) , but you're ultimately more versatile at the cost of a bigger program.

Harvey



In combination with the FLUKE 8840A DMM, they might turn into a much better curve tracer setup than the mentioned Grundig Digimess PN300 alone. More to come!

Tot ziens,

Magnus

[..]
A basic introduction corresponding to what Magnus does in his script is
here for example:

https://www.edn.com/design/test-and-measurement/4441692/How-to-automate-measurements-with-Python
I tried Python successfully for command communication (both serial and
GPIB) with my CSA803 but only to verify that it is possible.
(Magnus, I guess "a lot of water has flown through the river Rhein" while
you composed that Python script ;-)

Albert





Odd screw heads in a Tek 497P

radioconnection@...
 

None of my Phillips head drivers seem to properly fit the screws holding the boards in my 497P. It there a special tool that I need?

Peter

Re: Odd screw heads in a Tek 497P

ROLYNN PRECHTL K7DFW
 

None of my Phillips head drivers seem to properly fit the screws holding the boards in my 497P. It there a special tool that I need?
=============================================================

Pozidriv.

A Phillips will cam them out.


Rolynn
Tek Bvtn and Sunset 1966-1971

Re: Odd screw heads in a Tek 497P

Dave Casey
 

Tek hardware, before it was Torx, was largely Pozidriv. It looks a lot like
Phillips, but using Phillips screwdrivers on Pozidriv screws is a losing
proposition over time. Pozidriv screwdrivers and bits are readily available
in multiple sizes. I keep PZ0, 1, and 2 handy on the bench.

Dave Casey

On Fri, May 17, 2019 at 7:34 PM <radioconnection@...> wrote:

None of my Phillips head drivers seem to properly fit the screws holding
the boards in my 497P. It there a special tool that I need?

Peter



Re: Odd screw heads in a Tek 497P

radioconnection@...
 

Thank you. I will invest in a set of drives. Figured the Phillips drivers were a lost cause; so I will get what is needed.

Peter

Re: IMPORTANT: Photos are eating up our storage

Reginald Beardsley
 

I'd like to suggest that photo attachments be deleted after N days. If the source writes up an article in PDF format we keep that. And preferably transfer it to the wiki.

It's an "if you don't care enough about your work to organize it, why should we archive it forever" policy.

I separates the noise level stuff from the tutorials.

Reg

Re: IMPORTANT: Photos are eating up our storage

 

Hi Carsten,
I asked our members for suggestions when I posted initially about the storage problem. I appreciate the wide range of suggestions I am receiving.
Whatever solution our members choose it must take into consideration the needs of our worldwide membership.
The most important suggestions come from members that live in "unusual" places or that have to deal with "unusual" circumstances. They often deal with slow, limited, or unreliable connectivity on a daily basis and/or they pay for the data that they receive.

If you consider the enormous variation in connectivity of our worldwide membership and the modest scaling back of the size of the photos I mentioned in my reply to MarkGoldberg earlier today I hope you reconsider your conclusion that this mailing list has a tendency to ignore (read: damage) usability and usefulness, while setting up weird rules for solving “problems” that aren’t. There is a solution that doesn't require the 1024x768 JPGs that you mentioned as an example of damaging the usability of our forum.

Here is what I replied to Mark Goldberg today:

Dennis Tillman W7PF

-----Original Message-----
Sent: Thursday, May 16, 2019 10:36 PM

<snip>
I did additional research today to get a more accurate picture of the problem and the news is not good if we do nothing. We took 2.5GB of archives, files, and photos with us when we left Yahoo. Since we moved to Group.io 18 months ago we have used an additional 2.7GB of storage. That comes out to 2.7GB in 1.5years = 1.8GB per year. At that rate we will use up our remaining 4.8GB of storage in 2.6 years, or at the end of 2021.

Currently we allow photos to be as large as 4096x4096. If we reduce the maximum size /resolution to 2048x2048 it reduces the storage needed for a photograph by 1/4 which will postpone the inevitable by 4.8GB / 0.45GB per year= 10.6 years or the end of 2029, all things being the same. I can live with that.

In the meantime I will be monitoring our storage usage on a regular basis.

-----Original Message-----
From: TekScopes@groups.io [mailto:TekScopes@groups.io] On Behalf Of Carsten Bormann
Sent: Friday, May 17, 2019 11:26 AM
To: TekScopes@groups.io
Subject: Re: [TekScopes] IMPORTANT: Photos are eating up our storage

On May 17, 2019, at 19:59, Dale H. Cook <bridgewaterma@...> wrote:

800x600 pixel JPEG
Here is a nice example where 1024x768 was not quite enough:

https://www.eevblog.com/forum/testgear/keithley-196-system-dmm-teardown/

Forcing people to scale down their images until you no longer can read the markings on the chips is not bright.

For some reason, this mailing list has a tendency to ignore (read: damage) usability and usefulness, while setting up weird rules for solving “problems” that aren’t. I’ll shut up now (I only have a single Tek scope anyway), but I wonder what went wrong here.

Grüße, Carsten




--
Dennis Tillman W7PF
TekScopes Moderator

Re: IMPORTANT: Photos are eating up our storage

 

Hi Esmond,
I assumed it was linear because I have no basis to assume otherwise until I get some data over time that indicates otherwise.
I realize that, as taking and posting photos becomes easier all the time, it is likely to be an exponentially INCREASING growth rate as you mentioned. On the other hand, by spotting the trend when I did we are able to modify our behavior to increase the efficiency with which we use photographs. It is possible that could result in a reduction of the growth rate or, at least, a leveling off.

I would be satisfied with that.

Dennis Tillman W7PF

-----Original Message-----
From: EJP
Sent: Friday, May 17, 2019 3:05 PM
Subject: Re: [TekScopes] IMPORTANT: Photos are eating up our storage

<SNIP>
Can I also point out that when talking about the current growth rate we should not assume it is linear. One would expect it to be exponential.
EJP




--
Dennis Tillman W7PF
TekScopes Moderator

Re: IMPORTANT: Photos are eating up our storage

Chuck Harris
 

If you are going to delete the photos, then you might as well
delete the messages too.

The photos and the messages should exist for equal terms.

-Chuck Harris

Reginald Beardsley via Groups.Io wrote:

I'd like to suggest that photo attachments be deleted after N days. If the source writes up an article in PDF format we keep that. And preferably transfer it to the wiki.

It's an "if you don't care enough about your work to organize it, why should we archive it forever" policy.

I separates the noise level stuff from the tutorials.

Reg



Re: Odd screw heads in a Tek 497P

Sergey Kubushyn
 

On Fri, 17 May 2019, radioconnection@... wrote:

Yep. It is called Pozidriv.

None of my Phillips head drivers seem to properly fit the screws holding
the boards in my 497P. It there a special tool that I need?

Peter


---
******************************************************************
* KSI@home KOI8 Net < > The impossible we do immediately. *
* Las Vegas NV, USA < > Miracles require 24-hour notice. *
******************************************************************

Re: IMPORTANT: Photos are eating up our storage

Carsten Bormann
 

On May 18, 2019, at 04:00, Chuck Harris <cfharris@...> wrote:

If you are going to delete the photos, then you might as well
delete the messages too.

The photos and the messages should exist for equal terms.
Makes sense to me, but remember that all messages and their attachments have been sent to hundreds of people who can dig them up if needed.

https://groups.io/static/pricing says:

What Happens If I Go Over My Storage Limits?

We send you a warning when you've reached 80% of your storage limit. You can configure your group to either bounce messages when you've reached your storage limit, or to automatically delete old attachments to keep you under the storage limit. Photos and files are never automatically deleted.
So the group can be configured to automatically solve the problem we don’t have yet.

My recommendation:

(1) switch on attachments
(2) discourage using “photos and files” for information that really should be attachments
(3) configure to delete old attachments to keep us under the storage limit
(4) lean back and smile.

Eventually, groups.io will adapt the storage limits to falling storage prices, so the whole thing will bite less.

Grüße, Carsten

Re: IMPORTANT: Photos are eating up our storage

Tom Gardner
 

On 18/05/19 04:46, Carsten Bormann wrote:
On May 18, 2019, at 04:00, Chuck Harris <cfharris@...> wrote:
If you are going to delete the photos, then you might as well
delete the messages too.

The photos and the messages should exist for equal terms.
Makes sense to me, but remember that all messages and their attachments have been sent to hundreds of people who can dig them up if needed.
If they aren't stored on the server, how would

* new members access them?
* people search for information? Neither email program's searches nor most
forums searches are anywhere near as good as google.

Besides, there's no way I want to store 4GB of email messages on my machine!

Re: IMPORTANT: Photos are eating up our storage

EJP
 

(1) switch on attachments
Now this doesn't work for people who use the Web interface to post. There is no attachment facility.

EJP

Re: Odd screw heads in a Tek 497P

A Rhodes
 

Maybe they are Pozidrive? They look like Phillips but are NOT. The Pozi screw heads usually have a fine line impressed between each of the arms of the cross shaped receptacle in the screw head.

-Tony

Sent from my 1837 Babbage Analytical Engine

On May 17, 2019, at 8:33 PM, radioconnection@... wrote:

None of my Phillips head drivers seem to properly fit the screws holding the boards in my 497P. It there a special tool that I need?

Peter


Re: OT: I/V curve tracing made easy with Python and PyVISA

Albert Otten
 

Hi Tony,

It looks like you didn't find the necessary documentation?
Always have a look at the Tekwiki website. All you need is there, both for 2465 (+ options) and WR P6407.
As said by Harvey White a.o. in another thread there is no special software needed for the P6407.
If you like, the settings for WR can also be done via GPIB. Appendix A of the WR operators manual lists the additional GPIB commands for the WR.
Chuck Harris gave his opinion about using GPIB for this scope -- it's rather useless. It's nice to see that GPIB works and that you can download single measurement values, but the real advantage would be that you can transfer waveforms or screen images to a PC which isn't possible with this analog scope.

Albert

On Fri, May 17, 2019 at 10:23 PM, Tony Fleming wrote:


I purchased couple weeks ago the P6407 stuff, but it has no manual or any
instructions - I must find that information and print it....