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Heathcote Radio Listening Station

A cache by Team MavEtJu Send Message to Owner Message this owner
Hidden : 11/6/2017
2.5 out of 5
2 out of 5

Size: Size: regular (regular)

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How Geocaching Works

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Geocache Description:

Requirements: An FM radio receiver tuned in to 88.9 MHz, and a charged USB battery.

Read the story below, then drive over to WP1. Set your FM radio to 88.9 MHz.

Find the small container under the rocks, open it, take out the plug, hook it up, listen to the radio. The recording is repeated over and over.

No need to open the small container!

Heathcote Radio Listening Station

The origins of Heathcote Radio Listening Station lies with the experiments of Lieutenant George A Taylor, an officer in the Intelligence Corps of the Militia, who transmitted the very first military wireless signal in Australia. Their signal was in the form of Morse Code and was successfully received two miles to the south in a cave on a landmark known as Spion Kop. The landscape there is uniquely shaped to naturally divert the radio signals bounced of the ionosphere towards the Spion Kop cave, making it an unique location for the Australian Defence Force radio listening network, founded at the beginning of World War I. Because of the long delays between the capturing of the signals and the delivery of them to France and the UK, the information was often outdated and useless on the battlefield. However, the pieces of apparatus created by the engineers monitoring the signals showed their technical skills.

At the end of World War I, the Australian government under William Hughes decided to keep the listening network capabilities in Heathcote, a move which would prove later unvaluable with the Japanese invasion of Manchuria in 1931. Despite of the sharing of the received information by the Australian government at the League of Nations, the apathy of the other members allowing a country such as Japan to commit blatant aggression without serious consequences. Adolf Hitler was also aware of this, and he would follow Japan's example in aggrandization against the eastern neighbors in Poland. In the afternoon of the 1st of September 1939 the personnel in Heathcote received signals about the attacks on Wieluń and Danzig in Poland, but due to the struggles of the Menzies government losing the direct coalition support of the Country Party they were not dealt with adequately and important time was lost. Unlike World War I, the signals collected at the Heathcote listening station during World War II did receive on time at the various war rooms. Even German Enigma coded messages were received and forwarded to the UK for deciphering, but there have never been documented feedback of the impact of these messages.

After World War II and the rise of interference of commercial radio stations the Heathcote listening station was demoted in favour of higher quality listening stations in Woomera/Nurrungar, Alice Springs/Pine Gap and Parkes. The Heathcote listening station was formally closed on in 1951 and the military areas in Heathcote National Park and the Royal National Park were returned to the National Parks and Wildlife Services.

Report of the site visit of the former Heathcote listening station: John, Paul and me.

On Thursday 4 October 2007 we parked our cars on the Mirang Road Fire Trail entrance on the Princes Highway and walked towards the location of “Cave B”. Not much has been left of the above-ground buildings, nature has won the battle and the shrubs are hard to pass. While “Cave B” itself is easy to find, the location of the metal lid to enter the underground structure was only known from hear-say and it was covered by leaves and dirt: The metal detector taken along proved useful here. The stairs down are rusted but were still solid, even after more than 70 years they could easily hold our weight. The steps down are in three sections, each with a standing area after about four meters so you end up around 12 meters underground.

The old signage on the walls is still easy to read: The absence of people breathing out humid air and the locked environment have saved it well. At the bottom there are three exits, one towards the diesel generator room (locked), one towards a kitchen / rest area (also unlocked) and one towards the radio control rooms. The radio control room doors had a sign with “Authorized C2 personnel only” on it. In the first room there was a table with chairs and maps of the world on the wall. The pinholes on the maps showed the “recent” events in the world: Korea and Iran. That is: The Korean war in the 1950s and the fall of the Shah of Iran in 1953. It’s strange how the hotspots never seem to move. In the second room we found what we had hoped for, an old radio receiver. The car battery John had dragged along the path got hooked up and the tubes inside the radio started to glow. Despite that the receivers above ground were removed we still heard static crackling, which could be caused by the special characteristics of the landscape which made this location so useful for radio signal capturing.

And here is where it started to get creepy: The tubes in the receiver started to pulsate at about four Hertz for thirty seconds, turned bright white and then we heard a beeping sound that everybody will recognize as the signal first broadcasted from outer space back to Earth by the Sputnik. It lasted about ten seconds after which the tubes faded out and the battery connected to the radio receiver was too hot to touch for about five minutes. Everybody was speechless and had no idea what just happened. It wasn’t a recording, this was a live signal received but that signal had not been broadcasted for 50 years. John suggested that it could have been a short-circuit in the radio receiver which caused the battery to overheat and the tubes to go all weird, but that doesn’t explain the signal received. We tried the battery again but it was flat.

We were not sure what we wanted to do next. This whole experience had freaked us out enough that I wanted to go but nobody else was brave enough to say so. We disconnected the radio receiver and went back to the kitchen / rest area for morning tea and coffee. The table was not big enough for all of us to sit on, so Paul just walked around and ended up forcing the door to the diesel generator room. The fuel tank sounded empty when he knocked on it, but he pressed the buttons “for fun” he said, and the generator started up. The lights in the roofs started to glow, except the one in the first radio room. John ran back to the second radio room and plugged in the radio to the wall and the same thing happened as before: Just static crackling, for about fifteen minutes and nothing else. After that we got bored and investigated the rest of the map room and found an old work-instructions folder with how to operate the radio, the safe combination handling and access control to the site. The part which I found most interesting was the “sister stations alerts”, I wasn’t aware that these existed. What confused me was that the coordinates of the sister stations were in the Manchester in the UK, Saint Petersburg in Russia, Cape Town in South Africa and Kyoto in Japan. The instructions for the alerts were simple: The station identifier is broadcasted and then a countdown from 20 to zero happens. If zero is reached the sister station is considered compromised and will be remotely exterminated. The expected response to the countdown is a “All is well.”. These alerts happened once per day at a random time.

After reading this the lights dimmed for a second and John shouted “It’s doing it again!”. We ran towards the radio receiver and I joked from “I hope it’s more interesting than the Sputnik this time”. Then the tubes started to brighten up again and with a clunk the diesel generator turn off: Dead silence, but the tubes stayed bright white. Then a woman’s voice came through on the radio: “Kyōto no kaiwa… ni-jū.. jū kyū… jū hachi…”. We all looked at each other and [jū nana] and started to stutter from [jū roku] “That’s Japanese. What [jū go] is this? Is this the sister [jū yon] station alert?” “I’m getting out” Paul shouted, and [jū san] he ran to the door. “We need [jū ni] to tell her that it [jū ichi] is okay, everything is okay. Which number is she [jū] on?” “I don’t know, I don’t [kyū] know any Japanese, how are we [hachi] going to tell her that she has [nana] to stop?” “Tell her that ‘All is well.’!!!” [roku] “But I don’t know what that is in [go] in Japanese!” “That doesn’t matter, give [shi] me the microphone!” [san] and I said in a clear strong voice “All is well”... The next second was the longest in my life and then we heard “ni”. “OH KUT! RUN!”. While we ran out of the door towards the map room we heard a “chi” and I’m pretty sure that I heard a faint “zero” halfway up the stairs.

I don’t know if anything happened afterwards inside the underground structure but none of us was willing to go back inside and get the backpacks or the battery. Did we really run away from a 50 year old signal bouncing around the ionosphere, did we really expect that we could interact with it? Heathcote listening station is no-go territory for me, if anybody else is brave enough to go in, feel free...

Postscript - October 2017

After the experience in Heathcote listening station we have not gone back there, no way. It’s now ten years ago and I’ve been avoiding this place like it is cursed, well the whole subject is. In November after the experience I tried to get in contact with Paul and John, but Paul just blackholed me while John told me he needed some time alone to deal with what happened there. I’ve tried to contact John over time, he says “hi” and “how are you”, but for the rest he just keeps me away from him.

I’ve spoken with others about this and we have come to some form of a conclusion that it could have been ghost-signals in the ionosphere. The ionosphere is an ionized layer in the atmosphere, from about 60 kilometers up. It reflects radio signals so it can be used to bounce these signals over the horizon, a little bit like light on a mirror. The mirroring isn’t perfect, since the ionisation happens because of solar radiation and the night side of the planet has a less strong ionosphere than the day side. So it is possible for radio signals to partly bounce through the bottom layer of the ionosphere and and be bounced back at a higher level and then be bounced back by up the bottom layer. It’s like how light can be trapped in water or how black ice is formed: The signal, waves like light or radio, can go in a higher density fluid but not out of it again. It’s basic physics with refraction, nothing difficult or magical about it.

Stories about these ghost signals are well known if you talk to radio amateurs: Every year the RAF in the UK gets calls from amateur radio operators who received signals about bombers going down or bombers being lost and can’t find their base any more. The call-signs used and names referred to are often traced back by World War II bombing crews who didn’t return from their missions.

I tried to find and record more of these ghost-signals, but without daring to go back to the location of “Cave B” I had to do it with recordings found by others. I’ve made a collection of them available for this cache. Go to WP1 and tune your radio to 88.9 MHz and have a listen to them.

Apologies to anybody with remote knowledge on radios, signals and physics on the bullshit in this story

Additional Hints (Decrypt)

Choyvfurq pbbeqvangrf: "Pnir O". Ragre ng lbhe bja evfx.
JC1: Haqre ebpxf.
TM: Cebcreyl fuvryqrq.

Decryption Key


(letter above equals below, and vice versa)



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Current Time:
Last Updated: on 1/14/2018 11:02:35 PM (UTC-08:00) Pacific Time (US & Canada) (7:02 AM GMT)
Rendered From:Unknown
Coordinates are in the WGS84 datum

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