Listening to West Coast AM on 75 meters

Standing on  a crowded commuter train, going home at the end of the work day in Melbourne Australia, listening to a late night west coast AM QSO on 75 meters, 3870khz, using my Samsung smart phone, via W7RNA’s web SDR.  This is just one of the miracles of SDR and the Internet — the ability to use someone else’s station anywhere in the world, from almost anywhere in the world. My old elmer from my school days in the 1970s, Moss VK5TU, would turn his tuning knob in his grave if he could see this. KB6 and WB6es chewing the rag, on big AM transmitters.  You can almost smell the burning dust on the ultraviolet glass envelopes.  Pressing the tiny audio buds into my ear to shield some of the ambient train noise I hear the tone of the transmitter, rounded low-mids and bass.  It could be 1972. It’s a nostalgic and beautiful sound.


I’ve never listened to 75 meters before. In VK the 80m band finishes at 3700khz and the next 200khz are empty. With the exception of a 6khz DX window at 3794, a comparatively recent concession.   After about 30 minutes of familiar chatting, the AM boys sign off and the big carriers yield, the familiar prattle of low level sideband fills the space.  Over the next hour I switch my virtual receiver to LSB and tune a big 75 meter sideband signal. West coast and southern accents mix in a roundtable discussion of carburettors. Blokes are the same the world over. Then one of the OMs says something that shatters that illusion…

We turned our power down ‘ere, we’d be runnin’ around a thousand watts.

God bless America!


Update 16th June 2016: Stumbled on the AMI West Coast Net, a net of US West Coast AM enthusiasts, complete with a website, a kind of AM preservation society. It seems to run every Wednesday from 8pm PDT (Thursday 1300 EST for us) on 3870kHz AM. The net controller is Sharon K6IRD and Wayne W6IRD (Orange CA). These two featured in episode 12 of QSO Today. Net members were exchanging 4 digit AMI numbers and using TinyChat to exchange live video. Participants included K6FMD in San Diego, K6DU Jerry (Frasier Park), WA6HCX George (Santa Ynez), KF6FYD Steve (Longbeach), W6RFK Steve (San Andreas), WA6LDI (San Diego), AK6R Bob (Bonsall) and N6YH Billie (Tucson AZ). N6YH embodied the spirit of this group with his ex-commercial ‘big box broadcast’ transmitter, a Bauer 707. Here’s a video that starts with a line-up of four glowing 4-500s (1kW) so that you get the idea.  This thing apparently weighs in at 800lbs or 360kG, about the weight of a touring motorcycle!

Its nostalgic fun to listen to an AM round-table with a dozen or more big AM stations, mostly within a thousand kilometers of each other, people in no hurry and with the time to chat. And chat they do, the time just slips away like a glass of aged red wine as they reminisce about their old cars, defending the fortress of the 75 meter AM sub-band, their old rigs and all things AM. Recommended listening!

Tagged ,

3 thoughts on “Listening to West Coast AM on 75 meters

  1. Andrew VK1AD says:

    Cool SDR interface, listening now on 40m 7.272 MHz LSB. 🙂


  2. […] if listening to 75 meter AM from the US West Coast on the train going to work in Melbourne, Australia wasn’t entertaining enough, I googled to […]


Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s


My Projects

The Dragon and The Phoenix

Bard's Journey into the Collective Subconscious and How It Shapes Our World

Bryce Dombrowski's Projects

electronics engineering and more!

VK1 SOTA on 1.2 and 2.4 GHz

Andrew VK1AD | Amateur Radio | 23cm 1296 MHz | Summits on the Air


Design thinking, enterprise architecture, systems thinking, theory and practice.

Ripples in the Ether

Emanations from Amateur Radio Station NT7S


Fresh hacks every day


A fine site


Up the Hill

VK1VIC / VK2VIC Amateur Radio Blog

Summits of the Air , World Wide Flora & Fauna activations, CW (Fists #14192), (SKCC #14993)


Blog of Justin Giles-Clark VK7TW's SOTA and amateur radio adventures.

%d bloggers like this: