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Potato-'Tenna?

Can a vegetable atop your antenna help pull in distant stations? It seems so! This week on Car Talk, Ben from Jackson, Mississippi told a folkloric tale involving his dad, a Ford LTD, a country service station… and an Idaho potato.

You can hear Ben's call with Tom and Ray right here.)

Does it really work? Ray thought that one of Idaho's best could indeed pull in radio signals, possibly because it's got water inside, and is conductive. But, how does it actually pick up the radio signal? Ray had no idea.

What do you think? Would it work... and if so, how? Share your thoughts right here. And thanks!

Oh, yes indeed! A potato can and has functioned as an antenna. In high school in the early 1970s I drove a 1963 Pontiac Grand Prix (white, with red interior). Someone broke off the antenna, leaving only a four or five inch stub. (Remember: I’m in high school, and this 1963 car has no tape player. Disaster!) A fellow student–I no longer recall who–insisted a potato stuck on the stub would pick up radio signal. It worked very, very well. Decorative, too. And as the potato got older it loosened on the stub and would twirl drunkenly around when the car cornered.

A potato would not work as an antenna if there were no portion of the mast left. But in each case above, there is a portion of the mast and that is the antenna. The potato forms a “hat antenna”. A hat antenna is an antenna with a disk in to to capacitively load the antenna making it appear to be much longer electrically.

I am surprised that the automobile manufacturers didn’t adopt this system as standard equipment. When the car would come in for servicing, part of the service would be to change the potato for the radio.

One example, if you have an “atomic clock” or “atomic watch”, the signal that keeps it in time comes from a hat antenna in Bolder, Co. The signal is a LF (low frequency 60 kHz) signal that usually requires a very tall antenna. For this frequency, the antenna would be about 4100 feet tall.

The antenna used is about 400 feet tall with spokes radiating outward from the top. The spokes act like a giant capacitor to the radio signal making it think it is feeding a 4100 foot tall antenna. Because the spokes resemble a hat, it got the name “hat antenna”. It is also common with HAM radio operators.

A friend of mine from years past used to solder a Brillo pad to the top of his antenna. This was back in the days of AM and a little FM. He swore it increased his range. My vehicles could never pull in WLS or WOWO but his brought them in as clear as the local channels. I just never could get over the look of the Brillo pad so I never tried it.

WOWO! That brings back memories!
Back when I was in high school–in the early-mid '60s, NY area rock & roll radio stations only had public affairs and religious programming on Sunday nights. What was a teenager to do?

Well, believe it or not, my little Zenith transistor radio had very little trouble pulling in WOWO, even though Ft Wayne Indiana was fairly far from the coast of NJ, where I lived. And, since WOWO did play rock & roll on Sunday nights, that became my go-to station on Sunday nights.

From WOWO, I learned that Ft Wayne was known as “The Summit City”, and I also learned that there was a hamburger chain called McDonald’s that allegedly had wonderful burgers and fries. If I recall correctly, the McDonald’s commercials noted that there were two McDonald’s locations in the Ft Wayne area, with one of them being located on “The California Road”. McDonald’s was unknown in the NY metro area in those days, and the commercials (naturally) made it sound like they sold the greatest food in the world.

I think that the WOWO DJ on Sunday nights was Dick Chevalette (sp?).

Does anyone else recall listening to WOWO back in the 1962-65 era?

@VDCdriver–I am a little before your time, so I listened to WOWO in the mid to late 1950s. The DJ’s back then were Bob Siever, Jack Underwood, Bob Chase and another one that I don’t remember. I lived about 60 miles from Fort Wayne and WOWO was a 50,000 watt station, so the signal was very clear.
The station many of us listened to in these old days was a station from Nashville, TN that featured Randy’s Record Shop at night. I adjusted radios for several of my friends to pick up this station.
In your time period (early to mid 1960s, I was working on my master’s degree at Southern Illinois University in Carbondale, IIl. The station of choice down there was KMOX in St. Louis, Mo. I haven’t tried to tune in any of the above AM stations for decades.

I have also heard that this could be done as a short-term solution. The same principles that the potato can be used as an antenna are the same principles used when a potato is functioning as a battery powering a low-voltage lode like a digital clock or watch (1.5 volt DC or less).

The problem with a potato being an antenna, though, would be keeping it on the antenna (or what’s left of it). Potatoes need moisture to conduct the chemical reaction and that in turn would be used to pass the electrons from the potato to the antenna. Just like the antenna, it will respond to radio waves and have those electrons vibrate to that frequency so that the radio receiver can get the signal. When potatoes dry out, they are not such good conductors.

The other problem here is that the starches in the potato are also in the middle of a chemical reaction. This in turn does create an acid that over time might be hard on the metal of the antenna and the paintjob of the car.

Then there are the other problems that having a potato for an antenna would bring, animals. Insects, birds and even squirrels and mice would be eating away at the potato and you might also find other animals out there lured by the scent of food, which means that if you take this rigging up to Yosemite, you might be encountering bears looking for food and eating the potato.

I would use this as a last resort.

My antenna was snapped off. I tried the potato trick. All I could pick up was Irish music

WLAC, the Life and Casualty station played the “original” Rock and Roll.

I am familiar with the “skin effect” in electromagnetic theory: high frequency currents tend to travel on the surface of a conductor.

OTOH I’ve never heard of the “potato skin effect”.

The antenna used is about 400 feet tall with spokes radiating outward from the top … Because the spokes resemble a hat, it got the name “hat antenna”.

Close, but no cigar.

nist.gov/pml/div688/grp40/wwvb.cfm

Close enough, reread your own link.

Where are the “spokes” radiating outward from the top?

Your details of the antennae construction are incorrect.
Reread my link.

There are 4 “spokes” that go from each tower to the radiating element located in the center. That is stated right there in your link. There are two of these antenna’s, aligned north and south and spaced about 3/4 mile apart forming a phased array. The phased array gives the signal a little more strength in theeast/west direction, less north and south.

Wouldn’t it be easier to use a wire coat hanger? That’s what I used on my 1960’s Ford Galaxy, and it worked fine, with considerably less wind drag than a potato. I mean, if all you have is a potato, then go for it. But is it more likely you’ll have a potato or a coat hanger? I’m just saying :wink:

Good luck finding a wire coat hanger today, all I see are plastic.

Interesting. From Minnesota, we’d tune in Little Rock at night but always had dances on Sunday night so no big deal. Can’t believe Ft. Wayne was the go to place. Things must have sure changed-seems like Bible bangers is all that’s around there now.

So what do you do with an internal radio AM antenna? The one in my shop can’t pull in hardly anything anymore for some reason. With the massive reorganizations of the radio stations, just not much around locally. WCCO in Minneapolis used to be interesting at night, but now is broadcast out of St. Louis to Boston and MPLS. Really stupid. Only other one is the Art Bell fruitcake.