Is My Clock Radio Haunted? And If Not, Why Does It Play By Itself?

May 29, 2008 8:45 PM

Why does my radio play when it's turned off and there is no battery inserted?

In my room I have an old GE clock radio model number 7-4601A. Last night it just started playing on its own. Not how anyone would want to listen to it, it's softer and more crackly/static-y. Kind of reminds me of how a radio would play when there's a ghost present in a cheesy movie.

Naturally, I did some experimenting to see if I could figure out what's going on. I pressed the sleep button to let it play for a short period (>5 seconds) and pressed snooze to turn it back off. After about 10-15 seconds it would start playing for a bit, then stop. I also found out that it plays the station a little bit to the right of where I have it set on the radio station dial.

If it had stopped there I would have just thought it was being weird and not thought about it again. But earlier today I found out that it will seemingly randomly turn itself on in the same craptastic way described above multiple times after being turned off.

I tried taking the battery out, that didn't stop things. I didn't think it would either with it changing the radio station by itself like that, but it was something logical to check.

Honestly, the only thing I can think of is that the thing is haunted. The night before I noticed this I listened to Jethro Tull's Aqualung through my MP3 player and a set of portable speakers. But on the night the weirdness started I was listening to Dream Theater. So maybe there's a ghost that wants me to stay on classic rock?

I also have an FM transmitter that I tried to set on the same radio station that I had been listening to during the day. I don't think this should have any effect, but it is something different that I did between the two nights in question.

And for some reason, the episode of Are You Afraid of the Dark with Gilbert Gottfried called The Tale of Station 109.1 with a ghost radio station.

So, short of any paranormal stuff happening, why would my radio turn itself on and play like that?

posted by theichibun to technology (15 comments total)

It's actually possible to build a radio powered by nothing more than the radio waves it receives, but they aren't very powerful. I have no idea whether a normal (i.e. power amplified) radio can function in this way, absent a power source.
posted by Mr. President Dr. Steve Elvis America at 9:14 PM on May 29, 2008

I got a C in physics, but it's old, so could a faulty capacitor be to blame? Maybe it's stored up some energy and is releasing it in bouts or something.

And sentence or not, that is just about my favorite episode of Are You Afraid of the Dark. I had a crush on the guy who played the older brother in it.
posted by phunniemee at 9:18 PM on May 29, 2008

Check out this post.
posted by djb at 9:18 PM on May 29, 2008 [1 favorite has favorites]

Yeah, that's what happens when I'm tired and annoyed at the radio for interrupting me and I don't write the question straight through. It should say "And for some reason, the episode of Are You Afraid of the Dark with Gilbert Gottfried called The Tale of Station 109.1 with a ghost radio station is coming into my head."

Yes, the clock radio is plugged into a wall outlet. Would this maybe be an electrical issue that should be looked into?

Also, I hadn't heard of radios being powered by radio waves. And this would make perfect sense to me if it hadn't just started last night. Maybe I accidentally created one?

But even if this were the case, would that account for the sound coming from the speaker being from a different station than what the dial is set to play?
posted by theichibun at 9:19 PM on May 29, 2008

This would be a lot creepier if it wasn't plugged into the wall. Probably it's just a faulty power switch, although that doesn't really explain the slight rightward dial drift.

Nice taste in music, by the way.
posted by adamdschneider at 9:26 PM on May 29, 2008

Second djb's link. I had a similar experience with crappy unshielded computer speakers playing music from the radio without being plugged into my computer. Coiling up the cables seemed to reduce the problem.

It turned out that I was very near a college radio station, which was causing the issue, and I wasn't actually being haunted by ghosts.

_{Or was I?}
posted by burnmp3s at 9:28 PM on May 29, 2008

Could the needle pointing to the station have been slightly dislodged somehow? Dropped it recently? Smacked it in the early morning hours? Perhaps the needle is just displaced, and points just shy of where you intend to put it, while the internal mechanism is reading it in the right place? (Or the reverse of that.)
posted by phunniemee at 9:34 PM on May 29, 2008

A radio powered by radio waves is known as a crystal radio. Probably not what's going on. Sometimes a strong signal will cause some interference, but unless you're living under a radio tower I don't think that's it. Since it's plugged in, it's getting power from the wall. The battery is just for a backup in case of power failure, remove that and it still gets power from the wall. My guess is that the mode switch is set between "radio" and "alarm" which is causing random weirdness.
posted by Floydd at 9:34 PM on May 29, 2008

This is one of the ones with push-button controls on the top? I had one that would turn itself back on after you turned it off and do exactly what you're talking about with volume even when no one touched the dial. The buttons and dials get gummed up with dust and grime over time and contacts start sticking or just wear out.

If you leave the back-up battery out, unplug the thing and STILL have this problem, then all bets are off.
posted by weebil at 9:43 PM on May 29, 2008

If it's acting like a crystal set, it'll probably receive the same station no matter how you tune it (whatever AM station is strongest in your area, perhaps). But if it's still plugged into the wall, then I think weebil's flaky button theory is more likely.
posted by hattifattener at 11:54 PM on May 29, 2008

About the different stations, as a possible clue, I've had alarm clocks that allowed you to set the 'wake-up' station to something different than the 'play radio' station.
posted by hungrysquirrels at 3:17 AM on May 30, 2008

Broken electronics fail in myriad ways. Without looking at it, all is speculation.

What usually fails in most electronics is connectors and switches, stressed components (either marginally designed or suffering from an adjacent failure), components that age (like electrolytic capacitors and batteries), and static damaged components.

Not knowing anything about your radio, I am personally skeptical of the crystal radio explanation. FM uses something called a discriminator versus AM, which uses a detector (usually in the old days, a germanium crystal diode, hence the 'crystal' moniker). It uses magnetics (in most radios)... so it is slightly possible that your problems are due to high ambient radio signals, but you'd have symptoms in other electronics, too, and would probably pick up the station with your dental fillings!

I think you've got more going on there than adjacent RF intrusion, but it's not impossible. Relocating it to your girlfriend's house would eliminate that question quickly, if the problem is repeatable in your current location. My bet is that it is not location specific.

Actually, my bet is dirty mode switches first, followed by a problem with the controller that runs the radio, probably due to ESD (static) damage.

The trouble with questions/issues like this is that they pertain to devices that are so cheap as to not warrant ANY significant troubleshooting, unless it is for the pure joy of effecting a repair after understanding the problem.

When seeking help on this sort of thing... always provide the manufacturer and model numer, etc. "Radio" is a rather broad category.

Come to think of it, it could be a ghost.
posted by FauxScot at 3:35 AM on May 30, 2008

If playing with switches doesn't help, a ferrite choke might exorcise your ghost.
posted by gregoreo at 5:36 AM on May 30, 2008

A strong signal source nearby might be causing some bleedover, even when your radio is ostensibly "off". But yeah, most devices that run off of wall power continue to draw power while turned off, which will increase the likelihood of a radio pulling a signal. Residue buildup on the inside may cause a weak circuit connection, as mentioned above - leaving the radio constantly 'semi-on'.
posted by FatherDagon at 10:12 AM on May 30, 2008

Strong radio signals can provide sufficient current in a receiver circuit to be audible without (powered) amplification.

The strength is varying with radio propagation changes due to varying solar activity effects on the ionosphere and local weather (humidity). [This is an informed guess; I have a physics degree and an amateur radio license.]
posted by neuron at 3:03 PM on May 30, 2008