On 20 July 1969, in a back garden in Okolona on the south side of Louisville, Kentucky, a radio technician pointed a homemade antenna at the Moon and recorded Neil Armstrong and Buzz Aldrin. He was not connected to NASA, not receiving a television feed, and not relaying anyone else’s audio. If that is true it has an unusual property: it does not require NASA’s cooperation, or NASA’s honesty, to work.
Larry Baysinger, W4EJA, a staff technician at WHAS, a Louisville broadcast station on 840 kilohertz, and a licensed amateur since the early 1950s. Before Apollo he had built equipment to detect radio emissions from Jupiter and had printed crude weather-satellite images using an impact printer and carbon paper. He would be in his eighties now.
Glenn Rutherford, a 23-year-old reporter at the Louisville Courier-Journal, was there and wrote the story. They already knew each other: WHAS and the Courier-Journal were both owned by the Bingham family.
Chris Graney, professor of physics and astronomy at Jefferson Community & Technical College, rediscovered it in 2009, interviewed both men, and published through the American Radio Relay League in 2010.
Almost every objection comes from not understanding how Apollo’s very high frequency (VHF) radio was arranged. Two terms recur: AM is amplitude modulation, where the strength of the wave carries the sound; FM is frequency modulation, where its pitch does.
| Frequency | From → to | Carrying |
|---|---|---|
| 296.8 MHz AM | Lunar Module → both astronauts | Houston’s voice, relayed |
| 259.7 MHz AM | Commander’s backpack → Lunar Module | Armstrong and Aldrin |
| 279.0 MHz FM | Aldrin’s backpack → Armstrong’s | Aldrin only |
| 2282.5 MHz S-band | Lunar Module → Earth | everything, plus television |
Aldrin’s backpack did not transmit to Earth. It sent his voice to a receiver in Armstrong’s backpack; Armstrong’s unit combined both and sent them up on 259.7. So 259.7 carried both astronauts and nothing else — not Houston, not Collins, not the public-affairs commentary.
The S-band downlink had two modes. In flight it used phase modulation, where voice rode its own narrow subcarrier — like a single station on a crowded dial, which a modest antenna can tune to while ignoring the rest. During the moonwalk the Lunar Module switched to wide-band FM because it was sending television, and in that mode the voice, picture and telemetry are folded into one broad signal with no separate slice to tune. To get the voice you must demodulate the whole thing, which needs enough signal to capture the entire bandwidth at once.
That is why the big dishes were needed for the pictures — Parkes, a 64-meter radio telescope in New South Wales, and Goldstone, a 64-meter Deep Space Network antenna in the Mojave. And it is why a small station had a real chance on VHF and none at all on S-band.
The antenna was built originally as a radio telescope, from Frank W. Hyde’s “Radio Astronomy for Amateurs” (Norton, 1962). The type was invented by John D. Kraus in 1938.
Preparation took more than a year. Local experts told him it could not be done.
The weather nearly ended it. 20 July was cloudy over Louisville. The steering was motorized but had to be guided by eye — the two of them got behind the antenna and sighted along it like a rifle, at a Moon they could not see.
And then they lost the first part. Rutherford describes the celebration when the signal came through, and that nobody was watching the tape recorder. It ran out while Aldrin was describing how his vision failed stepping from sunlight into shadow. They loaded a fresh reel and recorded about 35 minutes on it, including the Nixon call.
The recording ends when the Moon set over Louisville.
This was the central open question, and the figure in general circulation — about 12 watts — turns out to have no primary source behind it. Four independent lines give 0.5.
The propagation study. NASA TN D-4915, “Lunar Surface Transmission Loss for the Apollo Astronaut,” December 1968, computes how far an astronaut could walk from the Lunar Module before losing contact, using the newest astronaut transmitter of 0.5-watt output. That paper could not have been written without the real number.
The link analysis. A Bellcomm engineering figure for the 259.7 link labels the transmitter 0.5 watts, with −1.7 dB of measured cable and triplexer loss from Apollo 14 and about −2 dB of antenna pattern loss.
The specification. The handbook figure is 0.25 W minimum — an acceptance floor a unit must clear, against a nominal it is designed to deliver. Not a rival claim.
RCA drawing 8657860, “Transmitter, AM (259.7 MHz),” dated 26 March 1968, shows the final stage using a 2N3375 power transistor. That is a published part. Its datasheet gives 3.0 watts output at 400 MHz — measured at 28 volts.
The backpack battery is 16.8 volts. Output from a class-C stage scales roughly as the square of supply voltage:
Now the constraint that settles it. An AM final stage must survive modulation peaks, and at 100% modulation the peak is four times the carrier.
| Carrier | Peak needed | Against a 2-watt part |
|---|---|---|
| 0.5 W | 2 W | exactly what it can give |
| 5 W | 20 W | 10 times too much |
| 12 W | 48 W | 24 times too much |
A half-watt carrier sits exactly at the part’s ceiling, which is what a working design looks like. The other two are not demanding hardware run hard. They are demanding hardware that does not exist on that drawing.
A link budget is an accounting exercise, and the name is literal: add and subtract down a column the way you would with money, except the units are decibels and the quantity is signal strength. Decibels are a logarithmic ratio, so they add rather than multiply — every 3 dB is roughly double, every 10 dB is ten times.
An 8 × 12 foot aperture has a theoretical ceiling of 19.25 dBi at perfect efficiency. If it behaved as an aperture — the newspaper and the ARRL both call it a horn — then 60 to 70% efficiency gives 17 to 18. If it behaved as a corner reflector, which is a dipole with two flat screens rather than a filled aperture, the published range for the type is 10 to 15. That disagreement cannot be settled from the surviving evidence, so both are carried.
| Antenna | Noise figure | Bandwidth | Signal-to-noise | With ground reflection |
|---|---|---|---|---|
| 13 dBi | 8 dB | 6 kHz | −27.9 dB | −21.9 dB |
| 16.2 dBi | 5 dB | 3 kHz | −18.7 dB | −12.7 dB |
| 18 dBi | 2 dB | 6 kHz | −13.2 dB | −7.2 dB |
An AM signal is a carrier plus sidebands. Detecting the carrier is far easier than copying the speech, because a carrier is a single tone you can hunt with a very narrow filter: at a 100 Hz bandwidth it reaches −1.9 dB. The carrier was findable. The speech was at the edge. Any analysis that computes the noise floor in a 1 kHz filter and then concludes speech was recoverable has conflated the two — a 1 kHz filter passes ±500 Hz, which detects a tone and carries almost no voice.
Four surviving files were analyzed directly for this page: one of 6 minutes 21 seconds and three short clips, two of which are byte-identical duplicates.
The strongest tonal line sits at 171.93 Hz, 50 dB above its surroundings, with companions at 57.37 and 114.73. Those are 1×, 2× and 3× of 57.4 Hz. Mains hum is 60, and a separate weaker line does appear at 60.06.
Two hums: one at true mains, one 4.4% flat. That is the signature of a tape recorded on one machine and played back on another running slow. Every voice on these files is about 4.4% flat and every duration 4.4% long.
Speech-to-background measures 4.0 dB on the six-minute file and 4.1 on the 39-second clip, with energy concentrated 300–3000 Hz and falling away sharply above. Four separate files, the same numbers — which says they came off one source under one set of conditions.
Ground-reflection fading works by the direct and reflected rays going in and out of phase as the path difference changes. That difference is 2h × sin(elevation), and the Moon moves 15° per hour.
The longest surviving file is 6 minutes 21 seconds — at most half of one cycle. Measured across it, the background drifts 2.6 dB monotonically, and the strongest slow modulation sits at a 23-second period, which is conversational rhythm.
The signal disappeared when the antenna drifted off the Moon and had to be re-aimed. A signal that lives and dies with where a directional antenna points is arriving from that direction.
The recording ends when the Moon set at Louisville. Karn checked this against a United States Naval Observatory ephemeris. The newspaper story does not mention it, so it is not a detail constructed for effect.
The audio arrived five to ten seconds before the same audio on CBS. A receiver cannot precede its own source; a stray from a local broadcast would arrive afterward.
The tape carries Armstrong and Aldrin, and not Houston, Collins or the public-affairs commentator. That rules out a rebroadcast, rules out 296.8 and rules out 279.0, identifying 259.7 uniquely. But it identifies the frequency, not the transmitter. The Lunar Module also carried a 5-watt transmitter on 259.7; had that been relaying, the signature would be identical. Against it: 296.8 was the working channel to the command module with 259.7 as backup, keying it would jam the Lunar Module’s own receiver, and the flight plan assigns 259.7 to extravehicular voice. And it would not rescue the arithmetic — five watts improves the link by about 15 dB and still leaves it 13 dB short. A recording made at the Bochum Observatory in West Germany shows the same missing-voices property.
Baysinger addressed this himself in 2009. A television station’s audio is an FM subcarrier beside an AM video carrier with sync pulses; a receiver tuned for AM voice at 259.7 could not have separated them into speech. It would have arrived as a harsh buzz. He heard speech.
The clips match NASA’s transcript at specific points — Aldrin on angle of departure and velocity, Armstrong on visibility, the exchange about standing on a cable, Aldrin on color, Aldrin on the temperature difference between sunlight and shade — indexed against pages 395 and 396 of the 633-page transcript.
Established. On 20 July 1969 a voice-modulated AM signal on 259.7 MHz was arriving at Louisville from the direction of the Moon — tracking the Moon, ceasing at moonset, arriving ahead of CBS, carrying exactly the two voices that frequency could architecturally carry, and matching the published transcript.
Not established. That the reception was clean, continuous or comfortable. The arithmetic forbids that at every assumption.
Not established by this alone. The landing. It establishes a transmitter on or very near the Moon. Someone can still propose an unmanned transmitter placed in advance — but that requires agreeing objects can be sent to the Moon, which is a much harder position to hold.
What it does uniquely is remove NASA from the chain. Almost every other line of evidence for Apollo passes through an institution. This one passes through a man in a Louisville garden with chicken wire, a surplus receiver, and a magazine that printed the frequencies.
He built it to catch NASA hiding something. He wanted the unedited feed — whatever was being cut before it reached the public. He got thirty-five minutes of two men describing shadows and soil, exactly as broadcast. Asked in 2009 whether anything had been edited out, he said no, everything went out on television, and that this was disappointing.
He went looking for something NASA had cut, and reported that there was nothing. That is a harder thing to wave away than a man who set out to confirm what he already believed.
Second tier: RCA drawing 8657860 and the acceptance test under NASA contract NAS 9-7508, held either at the Sarnoff Collection at The College of New Jersey or in the NASA records at the National Archives at Fort Worth. The Apollo 11 comm configuration before egress, in the Surface Checklist. The Bochum recording, compared clip for clip. Electronics World for August 1969, which carried a contemporaneous write-up of the whole system.