For the upper end; conducted measurements end where radiated emissions
start. Back in the mists of time someone decided that a ten meter
wavelength was something that could radiated fairly efficiently from
cables, so radiated emissions sounded like more of a risk to
telecommunications.
The 150 kHz number is more directly related to licensed services. The
limit was 450 kHz in the US until harmonization with the European
measurements. The US limit was based on protection of the AM broadcast
band. The European Longwave AM band extends down to 148kHz, so I assume
they simply rounded up to 150 kHz.
From a practical standpoint, if you stick with a 50 uH LISN, it starts
to deviate from 50 ohms quite a bit as you go lower.
Hope that helps.
Respectfully,
Brent DeWitt, AB1LF
On 8/12/2019 4:36 PM, [email protected] wrote:
Hello group,
Does anyone know why the conducted emissions for ITE products starts
at 150KHz and end at 30MHz? Why not start at 120KHz or 190KHz. Why
finish at 30 and not 40MHz?
Thank you
Peter
-
----------------------------------------------------------------
This message is from the IEEE Product Safety Engineering Society
emc-pstc discussion list. To post a message to the list, send your
e-mail to <[email protected] <mailto:[email protected]>>
All emc-pstc postings are archived and searchable on the web at:
http://www.ieee-pses.org/emc-pstc.html
Attachments are not permitted but the IEEE PSES Online Communities
site at http://product-compliance.oc.ieee.org/ can be used for
graphics (in well-used formats), large files, etc.
Website: http://www.ieee-pses.org/
Instructions: http://www.ieee-pses.org/list.html (including how to
unsubscribe)
List rules: http://www.ieee-pses.org/listrules.html
For help, send mail to the list administrators:
Scott Douglas <[email protected] <mailto:[email protected]>>
Mike Cantwell <[email protected] <mailto:[email protected]>>
For policy questions, send mail to:
Jim Bacher <[email protected] <mailto:[email protected]>>
David Heald <[email protected] <mailto:[email protected]>>
---
This email has been checked for viruses by Avast antivirus software.
https://www.avast.com/antivirus
-
----------------------------------------------------------------
This message is from the IEEE Product Safety Engineering Society emc-pstc discussion
list. To post a message to the list, send your e-mail to <[email protected]>
All emc-pstc postings are archived and searchable on the web at:
http://www.ieee-pses.org/emc-pstc.html
Attachments are not permitted but the IEEE PSES Online Communities site at
http://product-compliance.oc.ieee.org/ can be used for graphics (in well-used
formats), large files, etc.
Website: http://www.ieee-pses.org/
Instructions: http://www.ieee-pses.org/list.html (including how to unsubscribe)
List rules: http://www.ieee-pses.org/listrules.html
For help, send mail to the list administrators:
Scott Douglas <[email protected]>
Mike Cantwell <[email protected]>
For policy questions, send mail to:
Jim Bacher: <[email protected]>
David Heald: <[email protected]>
