Antenna placement safety

comptiger5000

Adventurer
I'm looking to add a GMRS rig (Midland MXT115) to my Jeep and am wondering about antenna placement. I run my CB antenna on a hood channel mount and am thinking of doing the same (on the other side) with the GMRS antenna (looking at a Comet SBB-5).

However, I'm slightly concerned about whether 15W of UHF on the side of the hood is a good idea, considering there won't be much other than glass between the antenna and the people in the front seats. Are there any potential concerns with this or is 3 feet or so from person to antenna sufficient to be safe?

If it's a concern, I could take the slightly harder road and mount a shorter antenna on the roof instead.
 

DaveInDenver

Middle Income Semi-Redneck
Excellent question!

It is a concern but generally speaking stations under 50W and mobile or portable with a push-to-talk do not require an exposure analysis. That's not to say you shouldn't be in compliance, because even though you are not required to do an analysis doesn't mean you're exempt from the reality of physics.

The ARRL and FCC have guidelines for this, in particular FCC OET Bulletin 65.

https://transition.fcc.gov/Bureaus/Engineering_Technology/Documents/bulletins/oet65/oet65b.pdf

The question of safe is not black or white. Zero RF exposure is safe and anything more may be or not. If you have a choice putting it on the roof is unquestionably better. But that's not to say the fender isn't.

Speaking from a w.a.g. standpoint having a 15W UHF transmitter that is FM but relatively low duty cycle wouldn't concern me if it was a few feet away. You're doing far more damage having a 5W handheld next to your face or even a 500mW cell phone next to your ear. Now 50W VHF, that would be more worry. BTW, also realize that most automotive glass is passivated, which means it actually does provide some slight RF shielding.
 
Last edited:

prerunner1982

Adventurer
Other than developing a twitch, you should be fine. :D

I agree with Dave, no longer than you will likely be transmitting you and your passengers should be A-OK! Great question.
 

comptiger5000

Adventurer
Alright. Based on that, I think I'll call it a non-issue and just plan to put the mount reasonably far forward along the hood / fender.
 

Forum statistics

Threads
185,538
Messages
2,875,655
Members
224,922
Latest member
Randy Towles
Top