Overdrive Radio

Hear AM/FM CB difference -- the story behind the FCC petition that launched dual-mode radios in U.S.

03.03.2023 - By OverdrivePlay

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For this edition of the podcast, Mark Karnes tells the story of the petition that the Cobra company put to the Federal Communications Commission some years back to allow the use of FM rather than just standard AM in CB Radios. With the petition granted in 2021, Cobra is now out with AM/FM dual-mode versions of all of its most-commonly-used models.

Karnes, a vice president with Cedar Electronics, Cobra's parent company, notes the transition from AM-only radios to dual modes won't happen overnight, yet notes when more FM-capable radios are in play, owner-operators will find better voice clarity over the radio when used in FM mode on both ends.

Hear a measure of that improved clarity here, as Overdrive Radio host Todd Dills recorded transmissions between two dual-mode versions of Cobra's Mini 19 radio, while running the same route in one vehicle as the other vehicle remained stationary. But for slight adjustments to squelch on both units, each radio remained at standard out-of-the-box settings other than dialing up Channel 15, otherwise quiet the night of the test. Drop into a little bit of the squawk between Ghostwriter and T-Bone in today's podcast, and get a feel for the principle difference in AM and FM modes –- sound quality and clarity when you're nearing the edges of range, or in situations with plenty interference that sometimes plague AM transmission.

More about what's currently available from a variety of makers of AM/FM radios: https://www.overdriveonline.com/equipment/article/15114521/fcc-approves-fm-mode-for-cb-radios

More about Cobra's line of dual-mode radios: https://www.overdriveonline.com/gear/product/15306989/cobra-electronics-cobra-unveils-first-dualmode-amfm-cb-radios

And as mentioned in the podcast, track back through our 2021 60th-anniversary special-edition episode exploring the CB's role in trucking culture as the "original social media," as many truckers have called it through the years: https://www.overdriveonline.com/overdrive-radio/podcast/15064061/the-cb-radios-historic-role-in-trucking-culture

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