ARRL RF Exposure Presentation via the ADXA Meeting


Bill Mader
 

Good afternoon Folks,

 


Wednesday afternoon we held our monthly meeting on Zoom with nine participants.  We had a guest from OR and a NMVHFS member from FL in addition to our regular members.  I played a new video from the ARRL Learning Center on RF Exposure and the new FCC rules on that subject.


The following attended:

N2GG, Gil, Kent OR

K6IR, John, Kent OR

N5SJ, Mike, Gallup NM

KS5Z, Terry, Lubbock, TX

K5WY, Ty, Los Lunas NM

WB2FKO, Mike, High Springs FL

AG5S, Alden, Santa Fe NM

KG5IDN, Ken, Rio Rancho NM

K8TE, Bill, Rio Rancho NM


I think Tom, K5TEE, of Albuquerque also tried to check it.  I didn’t spot him on Zoom but I did notice a message in my inbox from Zoom.  I received an audio notification whenever someone new logged in.  I apologize if I missed you, Tom.  He and I go way back to our auto racing days.


I included the locations of the participants for fun and to show that distance is no longer a barrier.  Considering “DX” is in the middle of our Association’s acronym, this seems significant.  I played a YouTube video that had participants from CT and MA to viewers from four other States, thanks to the Internet and the technology that supports and uses it.


The rumors about Zoom’s security issues are 98% users’ problems.  They upgraded their security long ago and Zoom is safe application/service used world-wide with great success!  Unless you don’t have a computer or Internet access, there is no valid reason for not joining us the last Wednesday of each month other than your choosing not to do so.


In case you missed the presentation Wednesday, here are some points of interest regarding the current FCC rules on RF Exposure:


New or changed stations must be complying now!

For stations built prior to 3 May 2021, 3 May 2023 is deadline to complete your assessment.

Use http://hintlink.com/power_density.htm for an on-line RF Exposure Calculator.

https://hamradioschool.com/rf-exposure-evaluating-your-station/ is a page with pertinent references and a link to an Excel spreadsheet you can download for use without Internet access.

The link to the free ARRL RF Exposure "book" is: http://www.arrl.org/rf-exposure.  This “book” does NOT contain the updated FCC rules effective 3 May 2021 but is otherwise extremely helpful.

https://www.eznec.com/eznec.htm free version good for modeling antennas like loops, dipoles, small Yagis, etc.

Radios "Marketed prior to 3 May 2021 are 'pretty much' grandfathered."

Remember, evaluation is required, but not measurements.

End-fed antennas and feedlines that are grounded are not necessarily safe due to common mode current.  They require current chokes.  Grounded doesn't necessarily "sink" the RF on the feedline to ground, eliminating RF near persons.

Transmission lines to truly balanced antennas do not radiate RF.  However, our antennas may not be perfectly balanced.  Consider using an MFJ-852 for detecting RF on coax and other cables to determine if you have an RF Exposure issue.

Contact the ARRL Lab if you get in a jam with some weird antenna situation, i.e., not included in the “standard” calculators.  http://www.arrl.org/arrl-assistance

Instruct family members so they are aware to avoid hanging out close to antennas.

Yes, we need to evaluate portable or temporary antennas.

Regardless of false rumors you and others you know may have heard, 5G has more sites, but is safer, not more dangerous, because it uses lower power.

Conduct the evaluation based on the worst case (longest transmission time and/or nearest distance).


If you want to view the presentation, it’s available at:  https://youtu.be/7dSieKF3rm0

trs@... for help

--
73, Bill Mader, K8TE
NM QSO Party 10 Apr 2021
ARRL New Mexico Section Manager
ARRL - The national association for Amateur Radio
Duke City Hamfest Chairman www.dukecityhamfest.org 17-19 Sep 2021
Secretary and Past President, Albuquerque DX Association 
W6H NM Coordinator, Route 66 On-the-Air 11-19 Sep 2021

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