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Technical Topics => Part 15 AM and FM Station Operation => Topic started by: ThaDood on January 19, 2022, 1956 UTC

Title: An AM Carrier-Current station from your livingroom? This dude does. And, gear???
Post by: ThaDood on January 19, 2022, 1956 UTC
Huh... Most folks doing a station either do it from the den, basement, attic, garage, or even a bedroom closet. This dude set-up in his living room. Eh... Why not???   https://www.radioworld.com/columns-and-views/workbench/workbench-retirement-starts-in-your-living-room
Title: Re: An AM Carrier-Current station from your livingroom? Good luck finding gear!
Post by: ThaDood on May 23, 2022, 1752 UTC
A friend is looking at starting AM Carrier-Current Broadcasting for himself. Problem is, the AM transmitters are not too hard to find, but finding Carrier-Current Couplers is getting to be more of a challenge, since when Radio Systems and LPB, Inc., couplers come up for sale on ebay, they go immediately. So, someone wants them. However, I found this on Digi-Key's site.   https://www.digikey.com/catalog/en/partgroup/power-line-communication-ac-coupling-circuit/81566     Has anyone ever tried this unit? It's meant more for data transmissions, kind of like DSL for PLC, (Power Line Communications.), a.k.a. same thing as carrier-current coupling really. What I don't see is how much power that this unit can take. That, and it's all fixed tuned-coupling, a.k.a. not adjustable like a Radio Systems CP-15 Coupler. Anyway, it's what is out there as a possible Carrier-Current start-up.
Title: Re: An AM Carrier-Current station from your livingroom? This dude does.
Post by: RobRich on May 25, 2022, 0448 UTC
The cct.pdf and low_power_radio_broadcasting_me.pdf docs available at the following pages have schematics for low-power AM transmitters and AM carrier coupling devices.

https://sites.google.com/site/lowpowerradio2/carrier-current-broacasting
https://sites.google.com/site/lowpowerradio/home/low-power-broadcasting-by-james-r-cunningham

Looks like the typical coupler is mostly a transformer, variable caps, and a couple of fuses for safety; plus a basic pad attenuator on the input side if needed. The cct.pdf doc has formulas for the transformer windings.
Title: Re: An AM Carrier-Current station from your livingroom? This dude does.
Post by: ThaDood on May 25, 2022, 1906 UTC
It pretty much is that for the AM C-C Coupler, an adjustable, transformer isolating, Medium Wave RF Tuner, for matching very low impedance values. One of the best resources that I have is the 1979 book from Ernest Wilson, (The Panaxis Productions dude.), of Carrier-Current Broadcasting Techniques: The Wired-Wireless. I really need to get that scanned to .PDF. Thanks, for the links! Always good to have Part #15 broadcasting knowledge INFO out there.
Title: Re: An AM Carrier-Current station from your livingroom? Build this Coupler!
Post by: ThaDood on June 22, 2022, 1843 UTC
My Minds.com page let me post .JPG PIC's of TEXT, but not upload .PDF's. So, If ya want to Roll-Your-Own-Coupler for AM Carrier-Current, it's certainly doable and some have done it.  https://www.minds.com/groups/profile/876322093051867136/feed   Someday, I want to scan Ernest Wilson's book in its entirety, but for now, I'll footnote those two pages.