Bode Plot Measurements with a Scope...

[three_jeeps]

I came across this article from Rohde & Schwarz and am curious if people are using this approach (or something similar) to verify their design.
https://on24static.akamaized.net/event/27/13/34/2/rt/1/documents/resourceList1600888178587/practicaltipsforaccuratebodeplotmeasurementsmiscen3608046292v010011600888177168.pdf

Its been a long time since I was doing this sort of work and am impressed with this capability.
Couple of questions:
1. Are people using this approach to verify their designs? (possible alternatives?)
2. Is this capability particular to Rohde & Schwarz scope?

Thanks
John

 

[Michael Kellett]

On 25/09/2020 18:21, three_jeeps wrote:

I came across this article from Rohde & Schwarz and am curious if people are using this approach (or something similar) to verify their design.
https://on24static.akamaized.net/event/27/13/34/2/rt/1/documents/resourceList1600888178587/practicaltipsforaccuratebodeplotmeasurementsmiscen3608046292v010011600888177168.pdf

Its been a long time since I was doing this sort of work and am impressed with this capability.
Couple of questions:
1. Are people using this approach to verify their designs? (possible alternatives?)
2. Is this capability particular to Rohde & Schwarz scope?

Thanks
John

Scopes from Pico Technology and Keysight can do this (that I know for
sure.) I think some LeCroy and Tek scopes can as well.
With Keysight it was quite an expensive software option, comes as a free
third party software with Pico.
I have a and R&S scope but find the Pico is a great deal easier to use,
the small screen on the R&S and scope like controls make it hard to use.
The Pico Tech stuff is all PC based.

MK

 

[Jeroen Belleman]

On 2020-09-25 19:21, three_jeeps wrote:

I came across this article from Rohde & Schwarz and am curious if people are using this approach (or something similar) to verify their design.
https://on24static.akamaized.net/event/27/13/34/2/rt/1/documents/resourceList1600888178587/practicaltipsforaccuratebodeplotmeasurementsmiscen3608046292v010011600888177168.pdf

Its been a long time since I was doing this sort of work and am impressed with this capability.
Couple of questions:
1. Are people using this approach to verify their designs? (possible alternatives?)
2. Is this capability particular to Rohde & Schwarz scope?

Thanks
John

This was mostly the territory of frequency domain instruments,
vectornetwork analyzers and such. Those still get much superior
performance. Once you have a scope with an integrated AWG and a
fair bit of processing power, it\'s possible to get the same
information from time-domain data.

Jeroen Belleman

 

[John Larkin]

On Fri, 25 Sep 2020 10:21:22 -0700 (PDT), three_jeeps
<jjhudak@gmail.com> wrote:

I came across this article from Rohde & Schwarz and am curious if people are using this approach (or something similar) to verify their design.
https://on24static.akamaized.net/event/27/13/34/2/rt/1/documents/resourceList1600888178587/practicaltipsforaccuratebodeplotmeasurementsmiscen3608046292v010011600888177168.pdf

Its been a long time since I was doing this sort of work and am impressed with this capability.
Couple of questions:
1. Are people using this approach to verify their designs? (possible alternatives?)
2. Is this capability particular to Rohde & Schwarz scope?

Thanks
John

I generally just use a function generator and a scope. That\'s easy to
set up.

Has anyone used the R&S scopes? Comments?

 

[Phil Hobbs]

On 2020-09-25 13:21, three_jeeps wrote:

I came across this article from Rohde & Schwarz and am curious if people are using this approach (or something similar) to verify their design.
https://on24static.akamaized.net/event/27/13/34/2/rt/1/documents/resourceList1600888178587/practicaltipsforaccuratebodeplotmeasurementsmiscen3608046292v010011600888177168.pdf

Its been a long time since I was doing this sort of work and am impressed with this capability.
Couple of questions:
1. Are people using this approach to verify their designs? (possible alternatives?)
2. Is this capability particular to Rohde & Schwarz scope?

Thanks
John

You don\'t need a fancy scope to do that--just bang on the input and
output with a nice square squarewave and watch it ring. Usually you
don\'t want more than a few percent overshoot, and no more than two
visible peaks, one positive, one negative. You may also care about tilt
on the pulse tops, which indicates low-frequency problems.

If you really want the closed-loop transfer function, the tool of choice
at low frequency is a dynamic signal analyzer such as an HP 35665A, and
at high frequency a vector network analyzer.

But for most wideband things, what you care about is stability and
decent transient response, and that\'s all there in the step response curve.

Cheers

Phil Hobbs

--
Dr Philip C D Hobbs
Principal Consultant
ElectroOptical Innovations LLC / Hobbs ElectroOptics
Optics, Electro-optics, Photonics, Analog Electronics
Briarcliff Manor NY 10510

http://electrooptical.net
http://hobbs-eo.com

 

[George Herold]

On Friday, September 25, 2020 at 1:21:29 PM UTC-4, three_jeeps wrote:

I came across this article from Rohde & Schwarz and am curious if people are using this approach (or something similar) to verify their design.
https://on24static.akamaized.net/event/27/13/34/2/rt/1/documents/resourceList1600888178587/practicaltipsforaccuratebodeplotmeasurementsmiscen3608046292v010011600888177168.pdf

Its been a long time since I was doing this sort of work and am impressed with this capability.
Couple of questions:
1. Are people using this approach to verify their designs? (possible alternatives?)
2. Is this capability particular to Rohde & Schwarz scope?

Thanks
John

I\'ve done this with a keysight \'scope. But there was
no menu options to fine adjust the scan range...
~1,3,10 frequency steps
I find a sig gen and AC voltmeter is better.

George H.

 

[Michael Kellett]

On 25/09/2020 21:39, John Larkin wrote:

On Fri, 25 Sep 2020 10:21:22 -0700 (PDT), three_jeeps
jjhudak@gmail.com> wrote:

I came across this article from Rohde & Schwarz and am curious if people are using this approach (or something similar) to verify their design.
https://on24static.akamaized.net/event/27/13/34/2/rt/1/documents/resourceList1600888178587/practicaltipsforaccuratebodeplotmeasurementsmiscen3608046292v010011600888177168.pdf

Its been a long time since I was doing this sort of work and am impressed with this capability.
Couple of questions:
1. Are people using this approach to verify their designs? (possible alternatives?)
2. Is this capability particular to Rohde & Schwarz scope?

Thanks
John


I generally just use a function generator and a scope. That\'s easy to
set up.

Has anyone used the R&S scopes? Comments?

I have recently bought an R&S RTA4004 which was on offer with all known
options for about £9250. (About 50% of list price so I\'m expecting a
replacement to be launched soon !)
It\'s competitive with the Keysight 3000 and 4000 series.
1GHz bandwidth, 4 channels, 10 bit, 5G/s sampling rate (2 channels), 16
channel digital.
Like all scopes in this format the screen is too small to really support
the features it offers. It can be connected to a computer via Ethernet
and there is a good web app which gives you a virtual scope on the PC,
but no increase in screen resolution.
The Keysight 4k series have bigger screens which would be nice.
I bought it to backup a LeCroy 610zi that I bought new about 6.5 years
ago. It\'s gone intermittent on the power supply and they won\'t supply
parts or service info, only a semi fixed price repair for about £2500 or
maybe £3700 depending on what they say is wrong with it.
The ergonomics of the LeCroy are way ahead of the R & S or Keysight
(when it starts :-(

I slightly prefer using the R&S rather than the Keysight MSOX 3024T that
I have.

I\'m currently testing a Pico Technology 6424E but I\'ve only had it a
day, so too soon for formal comment - but I do like the 42\" 4k
resolution screen and the Windows GUI. (It\'s a USB scope !).

In the end your choice is going to need to take into account what you\'ll
use it for.

MK

 

[server]

On Sat, 26 Sep 2020 09:16:26 +0100, Michael Kellett <mk@mkesc.co.uk>
wrote:

On 25/09/2020 21:39, John Larkin wrote:
On Fri, 25 Sep 2020 10:21:22 -0700 (PDT), three_jeeps
jjhudak@gmail.com> wrote:

I came across this article from Rohde & Schwarz and am curious if people are using this approach (or something similar) to verify their design.
https://on24static.akamaized.net/event/27/13/34/2/rt/1/documents/resourceList1600888178587/practicaltipsforaccuratebodeplotmeasurementsmiscen3608046292v010011600888177168.pdf

Its been a long time since I was doing this sort of work and am impressed with this capability.
Couple of questions:
1. Are people using this approach to verify their designs? (possible alternatives?)
2. Is this capability particular to Rohde & Schwarz scope?

Thanks
John


I generally just use a function generator and a scope. That\'s easy to
set up.

Has anyone used the R&S scopes? Comments?

I have recently bought an R&S RTA4004 which was on offer with all known
options for about £9250. (About 50% of list price so I\'m expecting a
replacement to be launched soon !)
It\'s competitive with the Keysight 3000 and 4000 series.
1GHz bandwidth, 4 channels, 10 bit, 5G/s sampling rate (2 channels), 16
channel digital.
Like all scopes in this format the screen is too small to really support
the features it offers. It can be connected to a computer via Ethernet
and there is a good web app which gives you a virtual scope on the PC,
but no increase in screen resolution.
The Keysight 4k series have bigger screens which would be nice.
I bought it to backup a LeCroy 610zi that I bought new about 6.5 years
ago. It\'s gone intermittent on the power supply and they won\'t supply
parts or service info, only a semi fixed price repair for about £2500 or
maybe £3700 depending on what they say is wrong with it.
The ergonomics of the LeCroy are way ahead of the R & S or Keysight
(when it starts :-(

I slightly prefer using the R&S rather than the Keysight MSOX 3024T that
I have.

I\'m currently testing a Pico Technology 6424E but I\'ve only had it a
day, so too soon for formal comment - but I do like the 42\" 4k
resolution screen and the Windows GUI. (It\'s a USB scope !).

In the end your choice is going to need to take into account what you\'ll
use it for.

MK

Our default scope is the Rigol 350 MHz 4-channel, which we\'ve always
managed to get upgraded to 500 MHz for free. We use it in test racks
and have Python libraries to talk to it. My favorite button is
DEFAULT, which means \"get me the hell out of here and be an
oscilloscope again.\"

We have one 7 GHz 4-channel LeCroy. The performance is fabulous and
the menus and nomenclature are bizarre to the point of unusable. Their
support people don\'t seem to understand it either. Cost about $50K.

My favorite scope is my ancient Tek 11802 sampler. It will die one of
these days and I will mourn its passing.

https://www.dropbox.com/s/d4n8qwgimdql2n4/T577c_40v.JPG?raw=1

It just makes so much sense.



--

John Larkin Highland Technology, Inc

Science teaches us to doubt.

Claude Bernard