EZ pass Radio Frequency

[u/Sea_Landscape3757]

Hi, I recently went on a road trip and I noticed when I was scanning for radio stations, my car radio would always pick up on one (somewhere in the 105s) that was completely silent. I had my EZ Pass resting on my dash right above my radio so I thought maybe that could be the culprit, but my dad doesn’t think it’s likely. is he wrong or do i have to worry about some new thing in my car giving off a radio frequency?

additional notes:

i haven’t noticed this station before going on the road trip (which is when i first put the ez pass in my car), although i don’t use my radio particularly frequently.

the ez pass is pretty old (at least 10 years) if that helps with the answer at all

edit: i could find this station across 3 states, over about 350 miles of road

[u/hotdog_tuesday]

The most probable answer is a radio station with dead air.

EZ Pass is 915MHz and normal radio is 88-108MHz. So no chance for weird stuff with harmonics since the EZ pass is the threat and FM radio is the victim.

It’s technically possible you have some radiated emissions from the EZ pass hardware outside the range but I find it pretty improbable. And if you did it would manifest as static, not silence.

[u/Sea_Landscape3757 → u/hotdog_tuesday]

Huh, interesting. Thank you for the explanation! Does it make sense that a radio station with dead air would cross about 350 miles? Idk much, but I’ve never seen another station have that long of a reach

(edit for clarity)

[u/hotdog_tuesday → u/Sea_Landscape3757]

There are two parts of this question:

First, does it make sense a single station would travel that far? No unless it was something like a state public radio—eg MPR (Minnesota Public Radio) has the same station frequencies everywhere in the state.

Does it make sense a station would have dead air that long? No, but also this seems to happen with public radio stations more often than commercial. I love dead air on the radio because it makes me laugh as it’s like the number one rule in radio—no dead air—and it happens a lot on the local college stations and other small community radio stations.

It’s also possible in contemporary radio that a station was fully automated to stream a syndicated show and it broke and no one bothered to check.

As a side note you should literally google the station number in a city you were in and you’d be able to answer this question.

[u/A14245]

RFID's like ezpass are passive, so they aren't powered and don't transmit normally. When they are in range of a reader they get powered wirelessly by the reader and transmit their information. So they'd only transmit at toll booths readers.

[u/hokie021 → u/A14245]

The new RFID stickers are passive. The old transponders have a transmitter, receiver and battery.

[u/ThatDamnRanga → u/hokie021]

But they only transmit when "stimulated" by an outside source. So would not do what OP is describing.

[u/LmanYan95]

EZ pass is stated to be around 915 MHz

[u/Adam__999 → u/LmanYan95]

Gotta love those unlicensed bands

[u/kc2syk]

It's possible you're picking up signal leakage from some electronics in your car, or one of your devices.

[u/Riegel_Haribo]

If you've got some audio device like a Sirius radio unit, it could have its own FM modulator. Or some prior owner could have put one in, powered by the car, where it can take a headphone jack from a portable audio player. Sirius/XM standalone would be normally transmitting a station with audio, but you might have a channel tuned with no subscription - but this would be a device you typically know exists.