Saturday, November 17, 2018

Q & A on TIGHAR Forum Analysis of Microphone Connector

By Joe Cerniglia

Preface: TIGHAR's Amelia Earhart Research Forum recently weighed in regarding my artifact report on the microphone connector found in the colonial village on Nikumaroro in 2017. To read this evaluation, click here:
Artifact Evaluation - Microphone Connector

To read the original paper on this blog to which the Forum responded, click here:
Connections of a Wayward Microphone Connector

I appreciate the Forum's efforts to analyze this complex artifact. Here is a basic Q&A to respond to this latest research effort:

Q. Richard Gillespie asked on the Forum, "Is this artifact (the microphone connector) of any significance?" How would you respond?

A. The question lies at the root of why one investigates an artifact. I believe all artifacts are significant to the extent that they represent a human life or lives. To greater and lesser degrees, every object has a history and, therefore, a story. Is Amelia Earhart's story more worthwhile than that of an anonymous colonist or member of the Coast Guard? I think the answer to that question depends largely upon the skills of the storyteller.

To improve one's ability in recognizing an artifact as potentially belonging to Amelia Earhart, one must study many artifacts that are not part of Earhart's story, but rather are part of the known story of Nikumaroro. Each artifact represents a learning experience, whether related to Amelia Earhart or not.

Regardless of known or suspected provenance, all artifacts are difficult to analyze.

Q. Has the artifact been misidentified?

A. No. The artifact was identified as an Amphenol 80-Series microphone connector, based on the inscription on its surface, which reads:
The 80-Series was specifically marketed as a microphone connector in every Amphenol catalog, Amphenol advertisement and trade publication mention of Amphenol we have been able to obtain.

Photo #1: the Amphenol 80-Series microphone connector with inscription

Photo #2: the Amphenol 80-Series microphone connector listed in context with its counterpart series in the 1960 Allied Radio Catalog.[1]

Q. Did the blog article state the connector was from Amelia Earhart's Electra?

A. No. The article did not state any certainties beyond the basic identification of the artifact as a microphone connector. It did not state the artifact was Amelia Earhart's. In fact, it stated that there was a significant possibility it belonged to the Coast Guard Loran station two miles away, or to the radio hut in the colonial village .4 miles away.

Q. Because of the fact that it has a single prong, Richard Gillespie has stated the connector found on the island was a "contact connector," not a microphone connector. Do you have documentation that single-prong contact connectors were marketed as microphone connectors?

A. Yes. Based on the c.1948 Amphenol catalog, and on other Amphenol catalogs we have seen, the Amphenol single-prong contact connectors were marketed as microphone connectors.

Photo #3: Close view of the single prong of the Amphenol microphone connector

Photo #4: Amphenol c.1948 Catalog listing of "Single Contact Microphone Connectors"[2]

Q. Were these single contact microphone connectors ever marketed as having been used on radios?

A. Yes. A circa 1969 Amphenol catalog specifically states that single-contact microphone connectors were used on "transmitters."[3]  A circa 1956 catalog makes no distinction between the number of contacts used in a connector and the fact that these connectors were used in transmitters.[4]  Transmitters are the principal component required to use a microphone with a radio.

Photo #5: Amphenol c.1969 Catalog details single-contact microphone connectors used with transmitters

Q. Were these single-contact microphone connectors used on the type of transmitter and microphone that Amelia Earhart brought with her on the world flight?

A. Perhaps not. Based on equipment recorded in the Luke Field inventory (documenting Earhart's first world flight attempt), Earhart most likely had a push-to-talk microphone aboard. A Forum member states that a push-to-talk microphone requires three prongs on its connector.[5]  We have found supporting evidence that this may be true. A 1963 trade publication lists a Shure model 440SL "grip-to-talk" microphone and then lists one of its components as an "Amphenol MC3M plug."[6]  Amphenol catalogs list these MC3M plugs as part of the 91-Series.[7]  The "3" in the part number signifies that it has three prongs. The artifact has one prong.

Photo #6: Advertisement for Shure grip-to-talk microphone (highlighted in yellow).

Photo #7: Amphenol c.1948 Catalog listing for MC3M microphone connector.

Q. Richard Gillespie stated the microphone connector would have been used with a movie projector in the Coast Guard Loran station. What evidence exists for this statement?

A. This is an interesting anecdote. A source citation would be helpful.

Q. Beyond Earhart's push-to-talk microphone and her transmitter, are there any other possible uses aboard the Electra for an Amphenol single-contact microphone connector?

A. Yes. The paper stated: "Both headphones and microphones are items that use microphone connectors to bring the cord to the chassis of the transmitter or receiver."[8]  The Amphenol c.1969 Catalog stated that single contact microphone connectors were used with headphones.[9]

Photo #8: Amphenol c.1969 Catalog details single-contact microphone connectors used with headphones.

Earhart's receiver, which was a potential attachment point for microphone connectors used with headphones, was mounted beneath the right seat in the cockpit.[10]  It would seem that a simple headphone set, used for receiving voice with no push-to-talk mechanism, would not require a three-pronged connector. A single-prong connector would probably suffice, but documentation is needed to be certain.

A photo of the underside of the copilot seat in the cockpit would be useful to see what kind of connectors were used to bring Earhart's headphone cord to the chassis of her Western Electric 20B receiver. The artifact microphone connector could also function as part of a patch cord extender for the headphones. It need not have been necessary to use it directly on the receiver chassis.

Q. Were headphones in use on Nikumaroro?

A. Almost certainly. We have a photo (see original paper) that showed a Coast Guardsman using headphones in a Coast Guard Loran station. We know the colony had a radio hut. Headphones were practically a requirement in these situations.
Photo #9: Advertisement for radio equipment commonly in use on Pacific islands prior to                                                                             World War II[11]

Q. Were Amphenol microphone connectors used for applications that included microphones but not radios?

A. Yes. The connectors were used for amplifiers. An amplifier can be used for a radio but also may be used for a public address system, or for stereo equipment such as phonograph players. The 1969 catalog lists other non-radio uses of a microphone connector such as "home recorders."[12]

Q. Were Amphenol microphone connectors used for applications that included radios but not microphones?

A. Yes. See the section on headphones above.

Q. Were Amphenol microphone connectors used for applications that included neither radios nor microphones?

A. Yes. The 1969 Amphenol catalog lists "theft alarms" and "coin-operated devices" as potential uses.[13]  The circa 1956 catalog lists "model railroad equipment" and "pin ball games."[14]

Q. Why didn't you mention these other applications in your paper?

A. The paper detailed the uses of microphone connectors most likely to have been encountered on the island. There were radios used in both the colonial village radio hut and in the U.S. Coast Guard Loran station. These radios seem the likeliest application for the microphone connector that was found in the colonial village. Theft alarms, coin-operated devices, model railroad sets and pinball equipment all seem unlikely to have been found on Nikumaroro, but further research from the Amelia Earhart Search Forum, and other blogs and individuals may say otherwise.

Q. Someone on the Forum stated that the connector can be dated on the basis of what it is made of (nickel or chrome), that the nickel connectors are older than chrome connectors. Is that true?

A. The idea that materials analysis could prove helpful in dating the artifact would be true if our documentation about the kinds of materials used on these connectors were not as complete as it is, and if the inscription on the artifact were not so unambiguous. The Amphenol catalogs clearly show the opposite of what the Forum stated. Nickel-plated microphone connectors are not older than chrome-plated ones; rather, they are younger. Starting in 1960, only the 91-Series was offered in "satin nickel."[15]  The other series (75s and 80s) were consistently offered as chrome-plated from the 1930s to the 1970s. Since the artifact's inscription shows it to be a member of the 80-Series, and since the 80-Series was consistently offered in chrome, any materials analysis would have no power to discriminate as to date of manufacture.

Q. Richard Gillespie states the wire on the connector was "pulled off" by colonists as a means of procuring a tool. Are there any additional possibilities for how the connector got separated from its trailing wire?

A. While it is possible the colonists modified the artifact, there are other scenarios the paper mentioned that do not involve contact with colonists at all. The island has been uninhabited for 55 years, longer than the actual Nikumaroro colony existed (1939-1963). The small abrasions on the microphone connector surfaces are consistent with what would be produced by tumbling from ocean deposition. This tumbling action, and time spent in the water, is sufficient to degrade significantly, without human assistance, the external cord that was once attached to the connector.

Q. Has the Amelia Earhart Search Forum ruled out the possibility the connector may possibly have been from Amelia Earhart's Electra?

A. As of this writing, it would not seem so. I appreciate the Forum's efforts to preclude the possibility the microphone connector is an artifact from the Electra. This effort, if successful, would add greatly to our knowledge of this artifact. I recognize, however, that proving the provenance of any artifact beyond a reasonable doubt is difficult. Even the in-depth research provided on this blog was insufficient to do this. I have felt that the best approach in reporting on this artifact is to leave open all of the possibilities and to research each one as thoroughly as I can.



[1] Advertisement for Amphenol Microphone Connectors. Allied Radio Catalog, 1960, p. 189.

[2] Amphenol Catalog: Radio Parts and Accessories, Synthetics for Electronics, High Frequency Cables and Connectors, 'A-N' Connectors and 'A-N' Fittings, c.1948, p. M-6. 23 Sept 2018.

[3] Amphenol General Line Catalog GL-2, c.1969, p. 5.

[4] General Catalog of Amphenol Components, Catalog B2, c.1956, p. 38.

[5] The International Group for Historic Aircraft Recovery (TIGHAR). "Artifact Evaluation - microphone connector." Online posting. 16 Oct 2018. Amelia Earhart Search Forum.

[6] Advertisement for Shure microphones. Allied Radio Catalog, 1963, p. 244. htpps:// 1 Oct 2018.

[7] Amphenol Catalog: Radio Parts and Accessories, Synthetics for Electronics, High Frequency Cables and Connectors, 'A-N' Connectors and 'A-N' Fittings, c.1948, p. M-6. 23 Sept 2018.

[8] Joseph Cerniglia. "Connections of a Wayward Microphone Connector." Amelia Earhart Archaeology, 12 Oct 2018.

[9] Amphenol General Line Catalog GL-2, c.1969, p. 5.

[10] Michael Everette. "A Technical Analysis of the Western Electric Radio Communications Equipment Installed on Board Lockheed Electra NR16020"

[11] Advertisement for Amalgamated Wireless. Pacific Islands Monthly, September 1940, p. 68. 25 Sept 2018.

[12] Amphenol General Line Catalog GL-2, c.1969, p. 5.

[13] Ibid., p. 5.

[14] General Catalog of Amphenol Components, Catalog B2, c.1956, p. 39.

[15] Advertisement for Amphenol Microphone Connectors, Allied Radio Catalog, 1960, p. 189. 1 Oct 2018.

Saturday, October 27, 2018

The 1940 Sextant Box Identified?

Earhart researcher John Kada seems to have identified the sextant box found on Nikumaroro in 1940, through persistent research testing the hypothesis that it was lost during the survey work performed on the island by crews from the USS Bushnell in 1939. John has given me permission to cite the article he's published on his blog, so here it is:

John's exemplary research thoroughly undercuts my conclusion -- shared with others in and around TIGHAR -- that the box was likely the property of Fred Noonan (as portrayed in both my novels, Thirteen Bones and Amelia Earhart Unrescued). Oh well, they're fiction.

Good work, John!

Tuesday, October 16, 2018

Tom Maxwell's Orona Atoll Hypothesis

Orona Atoll (Source: Wikipedia)

Tom Maxwell and the Orona Imagery

I was unaware of Tom Maxwell’s Orona Hypothesis until he was interviewed on Chris Williamson’s “Chasing Earhart” podcast, Episode 36 ( Mr. Maxwell was on Kanton Island (aka Canton) in 1972-75, tracking missiles from Vandenberg Air Force Base that were splashing down in the vicinity; he developed an interest in the Earhart/Noonan mystery and discovered a satellite image that he believes shows the Electra at the bottom of the Orona (aka Hull Island) lagoon. See for background data on Manra.

Mr. Maxwell has developed his interpretation of the imagery considerably in posts on the “Pacific Wrecks” forum (; see also ). 

The Hypothesis
To account for his observation, Mr. Maxwell developed an hypothesis that’s similar to the Nikumaroro Hypothesis in that he has Earhart and Noonan flying southeast from the vicinity of Howland Island, but he posits that Noonan, knowing that Canton Island had quite recently been occupied by U.S. and British scientists observing the 1937 solar eclipse (, had Earhart steer farther to the east, landing not at Nikumaroro but at Orona. He proposes that they splashed down in the lagoon, and that the plane remains there to this day.

Satellite Image, Marked by Mr. Maxwell

(Source: Tom Maxwell)

This perfectly plausible (I think) hypothesis is complicated by the fact that Orona was occupied at the time, as the site of a coconut planting/harvesting operation supervised by Capt. J.W. Jones, who had arrived there with his Tokelauan Burns-Philp employees in May 1937. Lt. John Lambrecht of USS Colorado landed in the Orona lagoon during the search for Earhart, and interviewed Jones, who reported no aircraft landings (See

Mr. Maxwell posits that Jones and his employees didn’t see or hear the Electra splash down because they were operating on the opposite end of the atoll, some 5 miles away. This strikes me as reasonable, based on my experience on Nikumaroro – if, of course, the plane went straight into the lagoon without any circling around.  

But assuming Earhart and/or Noonan survived the landing, why didn’t they go walkabout and find Jones and his colleagues? Mr. Maxwell proposes that Japanese forces encamped on Nikumaroro came and abducted them. From here on his hypothesis merges with the well-known Japanese Capture Hypothesis (c.f., and specifically with the postulates offered by Joe Klaas in his 1970 book Amelia Earhart Lives – though Mr. Maxwell does not necessarily subscribe to the details of the Klaas hypothesis.

There’s been a fair amount of discussion of Mr. Maxwell’s observations – mixed up with the thinking of Joe Klaas and his advisor Joe Gervais – on TIGHAR’s discussion forum; see and for examples.

When I heard Mr. Maxwell’s “Chasing Amelia” podcast I was intrigued, and puzzled by the imagery, but pretty startled by his notion of a Japanese presence on Nikumaroro. We’ve found no historical, archaeological, or other evidence of such a presence, though presumably it wouldn’t have left much.  So I asked him about his research and learned that the Japanese capture parts of his hypothesis are thus far based on speculation.

My Impression
On balance, I don’t think Mr. Maxwell’s hypothesis holds up; it involves too much speculation and is encumbered by too many unlikely variables. But there’s that image – which I have to admit looks to me an awful lot like an Electra. But like a lot of satellite imagery, the one of the “plane in the Orona lagoon” is pretty pixelated, and subject to interpretation. In interpreting such things, the human mind is very prone to cognitive bias; we want to see patterns, and we may “see” them even when they’re not there.

We had an encounter with such bias in 2010, when someone looking at Google Earth imagery saw what looked like the letters “ELP” spelled out in coral in a pond at the southeast end of Nikumaroro. It sure did look like “ELP,” and we imagined Earhart and Noonan spelling out a distress signal whose "H" had been lost to the elements. We even wrote a song about it (To the tune of the Beatles’ “Help”). But when we went to the pond and gave it a close look, there was simply nothing there but natural shelving coral; we’d been bamboozled by bias. And in the 1938 airphotos of Nikumaroro taken by the New Zealand Pacific Aviation Survey (, many of us could quite confidently see the outline of an Electra in the scaevola on Nikumaroro’s Nutiran shore –albeit in one photo pointing northwest and in another southeast. Only when the imagery was accurately scaled did we discover that the “Electra” was way too big to be what we thought we saw. Which was comforting since the area had been surveyed by our own field teams, revealing nothing.

Mr. Maxwell points out that when you look at imagery of the bottom of the Orona lagoon away from the “plane’s” location – and innumerable other places on the seafloor – you do not see Electra-shaped patterns of pixels; it’s only at that one spot. In a 5 October 2018 email to me, he argues for the likelihood that –

the pixels in the image are created by the L10E aircraft and not light and shadow upon coral formations. In the thousands of miles of shallow oceans-maybe light and shadow could create the exact likeness of a complex object. But such a rare phenomenon of light and shadow, in the likely spot a skilled pilot and navigator could find not far from their final destination, is extremely unlikely.

I don’t have an answer to this assertion, but I’m dubious; we don’t see “ELPs” scattered all over Nikumaroro, either, but that doesn’t make our 2010 “ELP” meaningful. But the patterns in the Orona lagoon are odd, and their location is intriguing.

The Solution
There’s one obvious way to test the Orona Hypothesis. Mr. Maxwell has plotted his ostensible Electra pretty precisely, and it’s not in deep water. It looks to be a pretty simple piece of underwater archaeological reconnaissance to check it out.  Someone ought to do it, but note: the inspection should be a piece of controlled, planned, fully reported archaeological reconnaissance, not just some divers with metal detectors poking around. And it needs to be done with full respect for the Phoenix Islands environment and the regulations of the Phoenix Islands Protected Area.

I’m grateful to Tom Maxwell, Joe Cerniglia, and Tukabu Teraroro for their reviews of this paper in draft.

Friday, October 12, 2018

Connections of a Wayward Microphone Connector

By Joe Cerniglia

Preface: With the permission of the government of Kiribati, we brought back a number of artifacts from the 2017 visit to Nikumaroro, to analyze and in time return either to the island or to the government's custody elsewhere. Joe Cerniglia has taken the lead in their analysis. This report is the first of several that Joe has in preparation. They'll illustrate the range of historically interesting subjects -- including but by no means limited to the fates of Amelia Earhart and Fred Noonan -- that can be investigated on Nikumaroro. TFK

On June 30, 2017, during the second day of the Betchart “In Search of Amelia Earhart” expedition to Nikumaroro (a.k.a. Gardner Island), Dr. Kimberly Zimmerman found a small cylindrical coaxial connector, just underneath a small mound of deadfall in the colonial village, about 100 feet northwest of the fallen ruins of the village co-operative store.

The connector was found in what we colloquially call the “new village,” that portion of the settlement that was developed after the death of its beloved first British administrator, Gerald Gallagher. This section of the village appears to have been developed primarily in the 1950s.[1]

 Photo #1: The connector as discovered

Photo #2: Close-up of the connector.

The connector was resting among a cluster of other interesting artifacts. About sixteen meters to its northeast, a small amber vial, colloquially known as the “Toluca vial” was re-located, after having first been discovered in 2015. (For more on the vial, see Roughly an equal distance due north of the connector was found, also in 2015, fragments from 2 small flat oval jars, with matching caps. Only one intact jar survived. This intact jar’s base was labeled “Bourjois,” a Parisian cosmetics company. Roughly an equal distance south southeast of the connector was found a circular metal object with triangular attachment points, with an inscribed part number (9-S-4378-L).  According to modern aviation parts websites, such as, this part number represents a navigation light.[2]

Photo #3: Map of objects found. With the exception of the Bourjois jars, locations were plotted with a Polar V800 GPS watch.

Artifact Description
This connector measures 1.5 inches in length. The mounting hole is 7/16 inches in diameter, and the microphone cable hole at its opposite end is also 7/16 inches in diameter. These connectors were built with a spring cord protector protruding from the cable hole.

Photo #4: Artifact connector alongside a pristine sibling 
with a spring cord protector

The spring cord protector on this connector has either broken off or rusted away. The spring, if present, would have reduced the clearance of the cable by 1/8 inches.[3]  When held vertically with its mounting end facing up, a three-line inscription on the artifact is visible. Above and below this inscription, two oxidized circular spots where small screws were once placed may be seen. The piece is pitted with tiny scratches and reddish oxidation marks. A knurled coupling ring is present near the mounting hole, but it has been shifted off its track so that it is stuck in place. A nub of wire, 3/16 inches in width, which has been bent in upon itself since it was collected, trails from the cable end. The artifact weighs 22.17 grams.

The Artifact Inscription
Inscribed in the center of the artifact are 3 printed lines. The first line is in sans serif block lettering, each letter of equal height. The line reads:

The second line is also in sans serif block lettering, slightly smaller in font size than the top line. The line reads:
The third and last line is also in sans serif, equal in font size to the second line. It reads:

The Amphenol Corporation: A Brief History
The company whose name is inscribed on the connector, Amphenol, was formed as the American Phenolic Corporation in 1932 by Arthur John Schmitt, an aviator, inventor and businessman who had predicted the then-emerging radio industry’s need for innovative radio parts. Amphenol survives today and is best known for its lightweight, durable, and high-performance circular connectors. During World War II, according to one biography, Schmitt’s company “made about 62 percent of all the electrical connectors used in U.S. planes.”[4] The company also made connectors for civilian uses as a wholesale supplier to radio manufacturers and retail supplier to hobbyists. Today the company provides connectors around the globe in many industrial applications such as aerospace, auto manufacturing, military needs, and mobile devices.

Catalogs and Advertisements: Artifact Identification
The 80-Series connector was listed in Amphenol catalogs, parts distributor catalogs, and advertisements as a microphone connector. Microphone connectors are useful in bringing cable from a microphone to an amplifier chassis, mounting a microphone on a stand, or providing a means of extending the cord of the microphone itself. Amphenol offered three series of microphone connectors, the 75-Series, the 80-Series and the 91-Series. They were made of a molded central dielectric element of black bakelite surrounded by a brass shell with a polished chrome finish.

The 91-Series was a deluxe model. It came with 3-or 4-prongs. The 80-Series was an intermediate model, with 1- or 2-prongs. The artifact is an example of the 1-prong variant of the 80-Series. The 75-Series was the entry level model, with 1-prong only. For most of its production run from 1935 into the 1970s, these three microphone connector series remained consistent in terms of general design, materials and construction, although the dimensions varied slightly over the years.

Amphenol introduced its first microphone connectors in December 1935.[5] The earliest advertisement offering them for sale appeared in early 1936.[6] The exact year in which the 80-Series model was introduced is not known, but it would seem logical that it would follow on not much later than the year in which Amphenol microphone connectors were first introduced.

Photo #5: Spring 1936 catalog offering of Amphenol microphone connectors

How Did It Get There?
There are three main hypotheses for how this connector reached the particular spot where it was found:
1.      Outwash from the Co-op Store and multiple house sites: This hypothesis presumes that the artifact resided semi-permanently within the village itself but was originally brought there, most likely by colonists.
2.      Material picked up elsewhere on the island and dropped by people en route to boats. This hypothesis presumes an accidental reason for its presence and does not necessarily presume colonial agency but may include Coast Guardsmen, British and American surveyors and explorers.
3.      Inwash south of the channel or eastward from the beach, washed in by force of wind or water, or both, from a storm surge. There are many examples of flotsam resting on the beach of the windward side of the island. If this hypothesis is correct, it would beg the question of just what was the original source. Was it a passing ship or some stationary object offshore?

Wear Patterns as Possible Deposition Clue
The extremities of the connector appear to be very much impacted, worn and beveled, with tiny uniform abrasions and one-millimeter linear scratches. These wear patterns are exactly what one would expect to see if the artifact had been thrown by the force of water and dragged, as in a storm, upon the abrasive, coral-strewn shore of the island. Under magnification, the wear seems slightly more noticeable on the projecting edges, but the connector is still relatively evenly worn. There are no areas completely free of wear. Dr. Richard Pettigrew, an archaeologist who was on the 2017 trip, contributed his expertise with wear patterns on artifacts, stating: “Tumbling in rocks produces even wear on all projecting surfaces, which is what I see on the artifact from photographs. It's a light object, so impacts would not be heavy, but many of them accumulate to generate wear that is visible at the right magnification and illumination. It won't be faceted (relatively flat) and focused wear, as you often get from tool use by people, but rather rounded and everywhere, as you get on pebbles in a stream bed.”[7]  

Photo #s 6 and 7:
Well-distributed wear patterns on the connector show light, uniform and small abrasions, as would be produced by tumbling from ocean deposition.

If Brought to the Village, By Whom?
The connector’s wear patterns, however, may not explain all of its provenance. Even if the connector spent time in the ocean, that would not preclude it from first having spent time on the island, for what may have been very mundane and expectable reasons. On the other hand, before assuming who or what brought the connector, a detailed assessment of each island population’s use of microphones and microphone connectors seems warranted, to the extent this is possible.

Loran Unit 92: The Coast Guard (1944-1946)
A radio microphone from a radio installation would seem to be a most likely source for a microphone connector, and it so happens Nikumaroro had a radio installation. Construction of the U.S. Coast Guard radio navigation station on the southern tip of the island (about 2 miles distant from the site where the artifact was found in the village) began about 1 September, 1944, with surveying, clearing and preparation work having been completed in the five weeks prior to that date. Loran Unit 92 first went on the air on 16 December, 1944.[8] The last servicemen departed the station in May 1946 and the station was dismantled shortly thereafter.[9]

On 24 July 1944 and on 18 August, 1944, an LCM (landing craft, mechanized) from the USS Spicewood was landed on Nikumaroro with equipment for clearing and building the station. On the first date, the landing was said to have occurred “three and one half miles from the site on the south side of the island at a point where the surf seemed the least hazardous.”[10] On the second date, the landing was said to have occurred “at the extreme northwestern tip of the island, about two miles from the landing.”[11] Both of these locations could have taken the LCMs within a short distance of the village site.

The LCMs could have communicated with the USS Spicewood by radio, and those radios could be a source of microphone connectors, so it would seem worthwhile to know whether the U.S. military purchased Amphenol products for use on boats. Also, the Loran station was restocked with supplies from PBYs that periodically landed in the lagoon, and these PBYs, too, could have been a source of microphone connectors.

If the microphone connector found in the new village was used by the military, it would be expected that it would meet military specifications. World War II witnessed a proliferation of military specifications for all types of equipment, including for the circular coaxial microphone connector found on the island. Some of these specifications predated the war itself. As of 1 November, 1939, all circular connectors on “aircraft, marine and other motorized units” were required to meet Army-Navy Aeronautical Standard AN-9534, which was superseded in 1941 by AN-WC-591.[12] [13]

Amphenol catalogs sampled from the 1930s through the 1970s all clearly distinguish between Amphenol products that were designated for use by the military, and therefore met the required military specifications, and those not designed for military use. Those meeting military specifications have an A-N number or, in the case of catalogs later than the 1950s, a MIL-specification number. The Amphenol 80-Series microphone connector was neither given an A-N number nor a MIL-spec. number in all the years it was offered. The Amphenol catalogs do not even class the 80-Series as unofficially approved for use by the military, as some of their other connectors were.[14]

Therefore, because 1) the Amphenol catalogs clearly distinguish the 80-Series microphone connectors from connectors designed for the military, and because 2) military specifications during World War II stipulated that in certain situations (i.e. transport), connectors with military part numbers had to be used, it is reasonable to suppose that military transport vehicles to and from the island, such as PBYs landing in the lagoon to replenish station supplies, LCM transports hauling equipment ashore to build or dismantle the station, or even bulldozers used in construction, are very unlikely sources for an Amphenol Series 80 microphone connector.

Wartime Amphenol Production of Microphone Connectors
Still, the possibility that the artifact was used by the U.S. military cannot be ruled out entirely. During World War II, Amphenol stated in an advertisement in a radio industry periodical that there was an ever-increasing “war production” of microphone connectors.[15]

Photo #8: Radio News wartime Amphenol advertisement 
announcing increased production.

Whether these wartime microphone connectors had A-N part numbers assigned to them is unknown. It is known that the artifact has no such number. What types of military situations (battlefield, administration, traveling shows for troops) in which these military microphone connectors were used is also unknown.

Inside the Loran Station
The regulations against use of non A-N parts, such as the artifact connector, appear to have been more strict while using them in moving vehicles than while using them in stationary buildings. Consequently, use of an Amphenol microphone connector inside the Loran station itself seems more plausible. A period photograph of the communications hut inside a Loran station shows a number of radio transmitters and receivers with cords and headphones, connected with specialized hardware of some sort.

Photo #9: Communications equipment at a Loran station[16]

Radio Equipment Commonly Used by the Military
It would be useful to know what kinds of microphone connectors were common in standard military applications during World War II. Although no survey could encompass every possible use, a survey of radio hardware does show certain trends.

One of the ways in which the military use of microphone connectors may be revealed is in the types of surplus military radio connectors dropped into civilian markets near the close of the war. Amalgamated Radio and Television Corporation advertised “Plugs and Jacks for every known application” in a 1945 publication.[17] It is interesting that the radio industry term “connector” is never even used in the advertisement; rather, a more pedestrian terminology (plugs and jacks) is used.

Photo #10: Advertisement for civilians to buy military plugs and jacks 
after the war ended.

These plugs and jacks are still sought after by collectors of old radio equipment and thus can be viewed in online sales and auctions. They appear to lack the sophisticated chrome exterior seen on the artifact. Instead, they have an encasing shell of black phenolic material, and are decidedly more primitive in appearance.

 Photo #s 11, 12 and 13: Typical World War II radio plugs and jacks.

While it is unknown exactly what the Loran stations in World War II were using for microphone connectors, or even if their use of such connectors was uniformly consistent, it would appear that the prevailing military trend for many situations was to use a reasonably durable but less expensive connector than the 80-Series Amphenol.

The Bushnell Survey Expedition (1939)
The U.S. Coast Guard was the largest of the U.S. military operations that ever visited and worked on the island, but there were other military personnel who visited more briefly. The submarine tender USS Bushnell left for survey work on Nikumaroro from American Samoa on 16 November, 1939[18]. By this time, military specification AN-9534, which required A-N part numbers for all circular connectors used by motorized military units, had been in effect for only two weeks (since Nov. 1, 1939). It is possible that the specifications were not yet observed by the Bushnell, and consequently, the ship may have carried circular connectors designed for civilian, not military, use. 

The Norwich City
The founding date of Amphenol in 1932 would definitely rule out the Norwich City, which went aground on Nikumaroro in 1929.

The Colonial Village Radio Hut (1939-1963)
The colonial village had a small wireless hut next to the rest house. This site is about .4 miles from where the microphone connector was found. So far as is known, this radio hut lacked ability to transmit voice, so presumably it did not require a microphone.[19] Still, an American microphone connector in the British radio hut cannot be ruled out.

Gerald Gallagher’s Personal Wireless Sets (1939-1941)
When Gerald Gallagher died on the island in 1941, his personal belongings were inventoried before and after packing them for shipment. These inventories show two wireless radio sets, a Radiola and an Ultimate.[20] Radiola was made by RCA. This line of radios was marked by frilly wooden cabinetry design. Since it was a receiver only, it had no need to have been accessorized with a microphone, or a microphone connector.[21] The Ultimate radio was a small mantelpiece receiver with Art Deco cabinetry, also without microphone inputs.[22]

Other Possible Sources
Other sources, consistent with the hypothesis that the artifact is flotsam tossed from a passing ship, include:
1.      The Nimanoa, Viti, other colonial vessels;
2.      Civilian ships, etc. used during the evaculation of Nikumaroro in 1963, or before;
3.      Passing yachtsmen, if any.[23]

What About Amelia Earhart (1937)?
There are some very logical associations that can be made between the microphone connector and known island populations. However, since Amelia Earhart and Fred Noonan have been hypothesized to have reached Nikumaroro while attempting to fly from Lae, New Guinea to Howland Island, it would also seem worthwhile to try to track down all of the possible associations between this Amphenol microphone connector and the 1937 world flight.

It turns out that there are several quite intriguing such associations.

Lockheed Model 10 (Electra) Associations (1960)
Well into the 1960s, the Lockheed Corporation maintained parts catalogs to assist owners in maintaining their vintage Lockheeds. The 1960 edition of the Lockheed Spare Parts Price Catalog for the Model 10 (Electra) lists a part number for a connector, 10606.[24] Both a modern electronics distributor, Mouser Electronics, Inc. and a parts supplier for commercial and military aircraft, WB Parts, Inc., have variants in their databases of this part number, an Amphenol crimp bucket connector.[25] In addition, Amphenol’s 2004 catalog made especially for aircraft manufacturer Bombardier Inc., lists 25 variants of this same connector.

Photo #14: The listing for an Amphenol connector from Mouser, Inc., a modern electronics supplier, is on the left; the listing of the same part in the Electra Spare Parts Price Catalog is on the right.

Photo #15: The modern Amphenol crimp connector is on the left; 
the artifact is on the right.

Photo #16: Cover of 2004 Amphenol catalog made especially for 
aircraft manufacturer Bombardier Inc.

Photo #17: From the Amphenol Bombardier catalog. 
This is a list of most of the variants of part number 10606, which may 
be found in the Lockheed Electra Spare Parts Price Catalog for 1960.[26]

What is lacking from this potential association between Amphenol and Lockheed is an Amphenol catalog that is contemporaneous (1960 or prior) to the Lockheed Parts Catalog, and which also shows this connector. None of the Amphenol catalogs thus far examined that predate 2004 contain this part number. Such a catalog may exist but has not yet been located.

There is also the possibility the Lockheed Parts Catalog refers to a connector from a manufacturer other than Amphenol. Glenair, Inc. today also manufactures the same connector with a variant part number. Glenair was also active prior to 1960.

Oddly, the 1960 Lockheed Spare Parts Price Catalog contains only prices, quantities, part numbers and descriptions. It contains no manufacturer names, so it is not known for sure whether Lockheed was buying connectors from Amphenol as stock parts for Electras, but it seems possible. This is interesting for a number of reasons, but it may also be no more than confirmation of the fact that for many decades Amphenol has been involved in the aerospace industry.

Western Electric Company Associations (1941, 1958)
Amelia Earhart’s Lockheed Electra carried a receiver and transmitter that were both made by the Western Electric Company. The receiver was the Western Electric Model 20B. The transmitter was the Western Electric Model 13C.[27]

When Earhart ground looped her Electra at Luke Field on Ford Island, Hawaii during the first world flight attempt in March 1937, the U.S. Army Air Corp inventoried the airplane’s contents prior to shipping it back to the mainland for repairs. This inventory stated that additional Western Electric Company radio components were aboard as well, including[28]:

Three (3) Western Electric Radio Head Phones, type No. 588A (2 equipped with ear cushions)

Two (2) Microphones with Cord, Western Electric type No. 631B

Both headphones and microphones are items that use microphone connectors to bring the cord to the chassis of the transmitter or receiver. All of this Western Electric Company equipment may be presumed to have been carried forward to the second world flight attempt.

No microphone connectors are listed in the Luke Field inventory, but these may have been left connected to the transmitter, or perhaps their presence is implied in the Luke Field inventory with the words “with Cord.”

It is not known what type of microphone connectors Western Electric specified in its manufacturer’s bulletins for the 588A earphones, the 631B microphones, the 13C transmitter, or the 20B receiver. Existing product information that survives does not reach this level of detail.[29]

However, five product bulletins from pre-World War II Western Electric amplifiers specifically call for two Amphenol microphone connectors “to use on cords.” Two additional Amphenol connectors are specified “to mount on chassis.” The amplifiers that call for these Amphenol microphone connectors and chassis connectors are Western Electric models 124-A, 124-B, 124-C, 124-D and 124-E. All of the models’ respective bulletins are dated “4-15-41.”[30]

Photo #18: Western Electric 124-C amplifier specifications for two 
Amphenol microphone connectors and two Amphenol chassis connectors.

The connectors specified in these product bulletins are all well-documented in an Amphenol catalog from circa 1948. In fact, these connectors appear on the same page on which the artifact microphone connector model is listed.[31] The microphone connectors called for in the Western Electric Company product bulletins are from the 91-Series, a close relative to the 80-Series, of which the artifact is an example.

Photo #19: These are the Amphenol connectors called for in the Western Electric 124-A, 124-B, 124-C, 124-D, and 124-E product bulletins. Those specified by Western Electric are highlighted in yellow. The artifact microphone connector is highlighted in pink.

It is not known whether the Western Electric Company began calling for Amphenol connectors in its products prior to 1941; however, after 1941, Western Electric’s customer relationship with Amphenol flourished. Western Electric would ultimately sign with Amphenol one of the largest connector purchase deals in electronics industry history.[32] By 1967, Amphenol was making the Type 57 micro-ribbon miniature connector[33] in large volume for the Western Electric Company, in partnership with another connector manufacturer, Cinch Manufacturing.[34]

Photo #20: 1958 catalog entry for micro-ribbon miniature connectors.[35] 
Western Electric purchased these connectors from Amphenol in one of the largest connector deals in the history of the electronics industry.

Because the radio equipment chosen by Amelia Earhart for the Lockheed 10E was designed and built by the Western Electric Company, it would be reasonable that the microphone connectors aboard the Electra might have been similar to the ones chosen in 1941 by the Western Electric Company for use in its amplifiers. They chose Amphenol.

Overall, the potential associations between the Amphenol 80-Series microphone connector found on Nikumaroro in 2017 and the world flight of Amelia Earhart and Fred Noonan in 1937 are much more intriguing than the associations usually encountered with a Nikumaroro village artifact, even as compared with those artifacts in the village that also have part numbers.

Partly this is due to the fact that the artifact’s inscription includes both a manufacturer name and a model number. As a result, the artifact’s basic identity is not in question. Additionally, the manufacturing history and purpose of the Amphenol 80-Series microphone connector has been much more extensively documented than is common for other objects collected and brought back from the island.

Still, the microphone connector is admittedly not an Earhart mystery ‘smoking gun,’ and the fact that it is not demonstrates how very difficult it is to find that 'definitive artifact,' the one that solves the Amelia Earhart mystery once and for all. Nikumaroro would be settled by Americans (1944-1946) and British-supplied colonists (1939-1963) only a few short years after Earhart disappeared en route to Howland Island in July of 1937. These settlers undoubtedly brought and even perhaps left behind radio parts of various shapes and sizes.

Whether or not these Nikumaroro settlers left behind this particular Amphenol 80-Series microphone connector is unresolved, but the probability of this having happened seems to diminish, not to increase, the more closely one studies the details.

Research continues on the following:

Amphenol manufactured microphone connectors between 1935 and the 1970s. Are there any attributes of the artifact microphone connector that would date it to perhaps a single year or decade? Can additional Amphenol catalogs be located that would assist in answering this question?

Do any product bulletins for the Western Electric radio equipment used aboard the Earhart Electra describe which, if any, microphone connectors were specified to use with these Western Electric products?

[1] Paul B. Laxton, "Nikumaroro," Journal Of the Polynesian Society 602, no. 2 and 3 (1951): p. 142.
[2] “Part listing for navigation light.” WB Parts. 10 Oct 2018.

[3] The amount of reduction in clearance from the spring cord connector is based on comparisons with the contemporaneous sibling connector of nearly identical dimensions.

[4] Thaddeus J. Burch, “Arthur J. Schmitt.” American National Biography. July 2002. Web. 1 Oct 2018.

[5] “Amphenol Microphone Connector.” Communication and Broadcast Engineering. 2.12, December 1935, p. 28, Column 1. 1 Oct 2018.

[6] Advertisement for Amphenol. Hall Radio Catalog, Spring/Summer 1936, p. 40, Column 2. 1 Oct 2018.

[7] Richard Pettigrew. “Re: Preliminary Observations on Coaxial Connector.” Message to Joe Cerniglia, Thomas King, Kenton Spading, and Kimberly Zimmerman. 27 Sept  2018. E-mail.

[8] Historical Section, Public Information Division, U.S. Coast Guard Headquarters. The Coast Guard at War IV, Volume 2. Washington, DC: 1946, pp. 91-95.

[9] See for a list of Coast Guardsmen on Gardner and the duration of each enlisted man’s service. The operational duration of Unit 92 itself was derived from these dates.

[10] The Coast Guard at War IV, Volume 2., p. 91.

[11] The Coast Guard at War IV, Volume 2., p. 93.

[12] Amphenol Catalog: Radio Parts and Accessories, Synthetics for Electronics, High Frequency Cables and Connectors, ‘A-N’ Connectors and ‘A-N’ Fittings, c.1948, p. M-26, Column 1. 23 Sept 2018.

[13] Connector Microtooling Systems, Inc. “Electrical Connectors and Tooling,” Arlington, TX: 2004, p. 8. 8 Oct 2018.

[14] Amphenol Catalog: Radio Parts and Accessories, Synthetics for Electronics, High Frequency Cables and Connectors, ‘A-N’ Connectors and ‘A-N’ Fittings, c.1948, p. M-12, Column 1. 23 Sept 2018.

[15] Advertisement for Amphenol. Radio News, June 1943, p. 40, full-page. 1 Oct 2018.

[16] The Coast Guard at War IV, Volume 2., p. 110.

[17] Advertisement for Amalgamated Radio and Television Corporation. Electronics, June 1945, p. 172, first column. 1 Oct 2018.

[18] Progress Report (of USS Bushnell) – 16 November to 17 December, 1939, inclusive. National Archives, 19 December, 1939, 9 Oct 2018.

[19] Thomas F. King. “Re: Preliminary Observations on Coaxial Connector.” Message to Joe Cerniglia, Richard Pettigrew, Kenton Spading, and Kimberly Zimmerman. 23 Sept 2018. E-mail.

[20] Gallagher Packing Inventory, date unknown, 9 Oct 2018.

[21] Advertisement for Radiola. Allied Radio Catalog, 1933, p. 6, full-page. 1 Oct 2018.

25 Sept 2018.

[23] Thomas F. King. “Re: Preliminary Observations on Coaxial Connector.” Message to Joe Cerniglia, Richard Pettigrew, Kenton Spading, and Kimberly Zimmerman. 23 Sept 2018. E-mail.

[24] Lockheed Spare Parts Price Catalog: Model 10 (Electra), Model 12, Model 18 (Lodestar), 1960, p. 3, Line 3.

[25] Part listing for Amphenol Bendix Connector.” WB Parts. 11 Oct 2018.
“Part listing for Amphenol Circular Crimp Connector.” Mouser, Inc. 11 Oct 2018.
[26] Bombardier Transportation Design Guide for Amphenol GT Series Reverse Bayonet Coupling Connectors, 2004, p. 20. 11 Oct 2018.

[27] Michael Everette. “A Technical Analysis of the Western Electric Radio Communications Equipment Installed on Board Lockheed Electra NR16020” , 11 Oct 2018.

10 Oct 2018.

[29] Earhart Western Electric 13C Transmitter Technical Information.;topic=1502.0;attach=7914
10 Oct 2018.

[30] Western Electric Product Bulletins for 124-A, 124-B, 124-C, 124-D, 124-E.
22 Sept 2018.

[31] Amphenol Catalog: Radio Parts and Accessories, Synthetics for Electronics, High Frequency Cables and Connectors, ‘A-N’ Connectors and ‘A-N’ Fittings, c.1948, p. M-6. 23 Sept 2018.

[32] Arthur J. Schaefer. Quest for Leadership: The Arthur J. Schmitt Story. Chicago: Cathedral Publishing Company, 1985, p. 75.

[33] I am using the completion date of the Hollywood, Florida Amphenol factory, discussed in Schaefer’s book as having been built to fulfill the deal with Western Electric, as the period in which production of the micro-ribbon miniature connectors rose to a high level.
Jessica Cattelino. High Stakes: Florida Seminole Gaming and Sovereignty. Durham, NC: Duke University Press, 2008, p. 49.

[34] Schaefer, p. 75.

[35] Allied Radio Catalog, 1958, p. 171.
10 Oct 2018.



Advertisement for Amalgamated Radio and Television Corporation. Electronics, June 1945, p. 172, first

Advertisement for Amphenol. Hall Radio Catalog, Spring/Summer 1936, p. 40, Column 2.
      1 Oct 2018.

Advertisement for Amphenol. Radio News, June 1943, p. 40, full-page.

Advertisement for Radiola. Allied Radio Catalog, 1933, p. 6, full-page.

Advertisement for Ultimate Radios.
25 Sept 2018.

Amphenol Catalog: Radio Parts and Accessories, Synthetics for Electronics, High Frequency Cables and
Connectors, ‘A-N’ Connectors and ‘A-N’ Fittings, c.1948. 23 Sept 2018.

Amphenol General Line Catalog of Amphenol Components, Catalog GL-1, c.1967.

Amphenol Microphone Connectors. Allied Radio Catalog,  1955a, p. 177.

Amphenol Microphone Connectors. Allied Radio Catalog,  1958, p. 171.

Amphenol Microphone Connectors. Allied Radio Catalog,  1960, p. 189.

Amphenol Microphone Connectors. Allied Radio Catalog,  1963, p.232 and  369.

“Amphenol Microphone Connectors.” Communication and Broadcast Engineering. 2.12, December 1935,
p. 28, Column 1. 1 Oct 2018.

Amphenol Microphone Connectors. Lafayette Catalog #710,  1971, p. 268.

Bombardier Transportation Design Guide for Amphenol GT Series Reverse Bayonet Coupling
Connectors, 2004, p. 20. 11 Oct 2018.

Burch, Thaddeus J. "Arthur J. Schmitt." American National Biography. July 2002. Web. 1 Oct 2018. 

Cattelino, Jessica. High Stakes: Florida Seminole Gaming and Sovereignty. Durham, NC: Duke University
Press, 2008.

Connector Microtooling Systems, Inc. “Electrical Connectors and Tooling,” Arlington, TX: 2004.

Earhart Western Electric 13C Transmitter Technical Information.
10 Oct 2018.

Everette, Michael. “A Technical Analysis of the Western Electric Radio Communications Equipment
 11 Oct 2018.

Gallagher Packing Inventory, date unknown,

General Catalog of Amphenol Components, Catalog B2, c.1956.

General Catalog of Amphenol Components, Catalog B3, c.1956.

Historical Section, Public Information Division, U.S. Coast Guard Headquarters. (1946).  The Coast
Guard at War IV, Volume 2. Washington, DC.

Laxton, Paul B. "Nikumaroro." Journal Of the Polynesian Society 602, no. 2 and 3 (1951): p. 142

Lockheed Spare Parts Price Catalog: Model 10 (Electra), Model 12, Model 18 (Lodestar). Lockheed
Aircraft Corporation. California Division, Burbank, California, USA. 1960.

Loran personnel roster. (n.d.). In Loran Historical Information.

10 Oct 2018.

“Part listing for Amphenol Bendix Connector.” WB Parts. 11 Oct 2018.

“Part listing for Amphenol Circular Crimp Connector.” Mouser, Inc. 11 Oct 2018.

 “Part listing for navigation light.” WB Parts. 10 Oct 2018.

Progress Report (of USS Bushnell) – 16 November to 17 December, 1939, inclusive. National Archives, 19
December, 1939,  9 Oct 2018.

Schaefer, Arthur J. Quest for Leadership: The Arthur J. Schmitt Story. Chicago: Cathedral Publishing
Company, 1985.

Western Electric Product Bulletins for 124-A, 124-B, 124-C, 124-D, 124-E.