Midway Communications Facilities
A collection of photos from Charles E. Kinzer (Navy ETN2 on Midway 1966-1968), taken during his time working on Midway in the 1960s.
Microwave Link
ITT-Kellogg microwave equipment which was in its own room in a corner of the transmitter site building. The big silver knobs switched 101 channels between the microwave mux/demux equipment and the undersea cable hardwired connections.
Microwave Link
ITT-Kellogg microwave equipment which was in its own room in a corner of the transmitter site building. The big silver knobs switched 101 channels between the microwave mux/demux equipment and the undersea cable hardwired connections.
Microwave Link
ITT-Kellogg microwave equipment which was in its own room in a corner of the transmitter site building. The big silver knobs switched 101 channels between the microwave mux/demux equipment and the undersea cable hardwired connections.
Microwave Link
ITT-Kellogg microwave equipment which was in its own room in a corner of the transmitter site building. The big silver knobs switched 101 channels between the microwave mux/demux equipment and the undersea cable hardwired connections.
Microwave Link
ITT-Kellogg microwave equipment which was in its own room in a corner of the transmitter site building. The big silver knobs switched 101 channels between the microwave mux/demux equipment and the undersea cable hardwired connections.
Microwave Link Dishes
Closeup of the microwave link dishes aimed toward Eastern Island. Part of a backup system should the undersea 101 cable fail.
FRT-24 & FRT-39
AN/FRT-24’s near, AN’FRT-39’s further down the row.
FRT-24 & FRT-15
AN/FRT-15’s (3 kW) in the foreground, AN/FRT-24’s (1 kW) further down the row.
FRT-15
AN/FRT-15 transmitters which were 3 kW. An amusing thing is that these were not set up for CW keying and the signal from the Radio Control building actually turned high voltage on and off. Sometimes they would incorrectly request us to set one of these up on some frequency and then we would hear a big relay slamming on and off in the transmitter and we immediately took the transmitter down and suggested to them perhaps they might prefer an AN/FRT-39.
Drafting Board
Located in a room extending off to the side of the main building. The room was also used as a lounge with a TV and chairs and had some wall racks with spear guns owned by some of the guys. Sometimes drawings had to be made or modified. But mostly this was used with a Leroy lettering set to professionally letter spines for binders that held technical manuals. A Leroy set has templates of lettering types and sort of little tracer pantograph and a Rapidograph style ink pen. All manuals were put in identical style binders with identically lettered spines. This made it easy to see if a manual had been left laying around loose somewhere. It kept them easy to identify and prevented them getting lost.
Antenna Farm Nitrogen Filled Coax
Part of the antenna area surrounding the transmitter site.
Aircraft Beacon Transmitters
A view of just the two aircraft beacon transmitters. I have been unable to remember or find out the transmitter model and manufacturer. I do know that it had an old Navy military designator as “T” something. I think just three letters and no number. In between the transmitters is a narrow cabinet that contains a motorized rotating keyer for Morse code. It sent out “NQM”.
Aircraft Beacon Transmitters & FRT-39
The two large aircraft beacon transmitters (operating at 379 kHz at the time) on the left, and one of the rows of AN/FRT-39 transmitters on the right.
RLP Antenna
An overall shot of one of the three rotating log periodic antennas with a person in dark pants standing at the bottom for scale.
RLPA Closeup
Elements of one of the three large rotating log periodic antennas for HF transmitters. I was told at the time these antennas cost a quarter milliion dollars each to install.
Transmitter Site Office
Near the entrance to the building. Also near the entrance was a little kitchenette, bathroom, and parts stockroom. The clipboards above the desk have copies of requisitions for parts and supplies that are waiting to be ordered, received, or ordered and not yet received. On the bookshelf to the left you can see some of the equipment manuals all bound identically with neatly labeled spines. Everything from transmitters down to Tektronix oscilloscopes to HP 5245L frequency counters down to test meters.
Transmitter Site Nerve Center – Receivers
This is directly across from the area in the photo with the teletype and patch panels. It had some receivers and a couple of speakers. All of the time (if not being used for some sort of test) those speakers were blaring out KMTH AM radio. The volume was high to overcome the loud roar of all the transmitter cooling blower motors, especially form the AN/FRT-39’s.
TAB-7
An ancient transmitter even then. It was set up at all times for 500 kHz which was the international emergency frequency at the time. But we would occasionally also test it at 470 kHz which was an alternate frequency.
Screen Room with URR-50
This was a screen room in roughly the center of the large transmitter bay. The equipment at the right is an AN/URR-50 VLF receiver – comparator – frequency standard. It was never used during the time I was there. Which is too bad because it would have made a terrific external standard for the synthesized AN/FRT-39 transmitters. I did get it working and one repair was to replace a little step up transformer needed to provide high voltage for the Nixie tube display. This was nothing more than showing the switch positions of the frequency selector knobs which went round and round with no stops, no panel legend, and no knob pointer. One of the switch wafers did nothing more than connect to the various number cathodes on the Nixie. The step up supply was needed so the unit could operate from a 24 VDC battery backup. So if you lost that little power supply (and it’s custom made and potted little transformer was prone to failure) you could not tell what frequency you were at. Nixie tubes were quite the rage at the time and probably designed into this thing as an afterthought to make it look neat. The little power supply circuit isn’t part of the regular power supply area, but slapped onto the phase detector module board.
FRT-24 & FRT-39 Rows
AN/FRT-24 transmitters on the left (and three AN/FRT-15 at the far end of left row) and AN/FRT-39 transmitters on the right.
Old Transmitter Site & RLPA
This very large Quonset hut was the former transmitter site. Now just being just being used for storage with a lot of ancient equipment. It was fun to look around in there. It is long since gone, but in Google Earth and other images you can still see the concrete pad where this building was. One of the three rotating log periodic antennas happens to be next to it.
See more photos from Midway:
And read more about the history of KMTH, Midway’s broadcast station:
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