Liberty ship was the name given to the EC2-S-C1 type ship designed for "Emergency" construction by the United States Maritime Commission in World War II. Liberty ships were nicknamed "ugly ducklings" by President Franklin Delano Roosevelt.
The first of the 2,751 Liberty ships was the SS Patrick Henry, launched on Sept. 27, 1941, and built to a standardized, mass produced design. The 250,000 parts were pre-fabricated throughout the United States in 250 ton sections and welded together in about 70 days. One Liberty ship, the SS Robert E. Peary was built in four and a half days. Each ship cost just under $2,000,000 to build.
The Liberty was 441 feet long with a beam of 57 feet. Her three cylinder, triple expansion marine steam engine was fed by two oil burning boilers. The engine produced 2,500 hp thus propelling the ship at 11 knots. Five holds could carry over 9,000 tons of cargo, plus airplanes, tanks, and locomotives could be lashed to the deck. These ships carried a merchant crew of about 44 and 12 to 25 Naval Armed Guard. The Brown is only one of two operational Liberty ships left.
Presented here is the radio room of the S.S. John Brown. The room is located on the port side behind the bridge. The free floor space in the room is about 6 feet by 8 feet.
|All equipment in the radio room was supplied
by Radio Marine Corporation of America, the marine division of RCA . This
photo shows the Model 3U Radio Unit standing against the forward bulkhead.
It was fitted with a work surface. (Photo by Jerry Proc)
1) Type 'C' Crystal Radio. Range: 350-515 kHz. It used a cat's whisker.
Each transmitter was equipped with RM28 keys.
|Standing against the starboard bulkhead of
the radio room and at right angles to the 3U console, was the other radio
unit. (Photo by Jerry Proc)
1) Motor generator transfer switch.
Saul B. Yochelson of the Lane Victory radio department explains the differences between the 3U and 4U radio units.
"Originally, Liberty ships only had medium frequency (MF) radio equipment. MF was considered as 500 KHz and down. The integrated modular unit was designated as an RMCA-3U or an equivalent made by Mackay Radio. The 3U had three frames: the left one contained the Auto Alarm, the center unit housed the MF AR-8510 receiver and the main ET-8024A MF transmitter. The right frame contained the AR-8025 emergency MF transmitter along with various switches for controlling the battery chargers.
Later, perhaps in 1944 or 1945 (I first saw such an installation in mid-1945), HF rigs were added to Liberty ships. These were implemented by a fourth frame that was installed at right angles to the 4U, between the Radio Room door on the starboard side of the Radio Room and the 3U. The added frame contained an HF receiver (the 8506), the 8023 HF transmitter, and a transfer switch that was used to switch the motor generator (in the base of the 3U) between the MF and HF main transmitters. Technically, this added HF frame was not part of the RMCA-3U.
In contrast to the Liberty ships, Victory ships were always outfitted with integrated MF and HF equipment. Essentially, a fourth frame was added between the Auto Alarm frame and the MF frame and the integrated modular system was designated as an RMCA-4U. Again, Mackay made a similar unit. If one looks closely, the left frames of the 3U and 4U are the same, the second frame of the 4U is the same as the "outboard" Liberty Ship HF frame and the two rightmost frames of the 4U are the same as the two rightmost 3U frames. Thus, the 4U had the same components as the augmented 3U but arranged in one, flat, row.
Interestingly, the HF transmitter on the John Brown uses a VCO while the similar HF transmitter on the Lane Victory is crystal controlled. I sort of remember hearing that most of the 4U HF transmitters were converted to crystal control after the war".
Liberty ships had two main antennas. Regardless of wartime or commercial operation,
when the booms were operating it was necessary to disconnect one end of each antenna, lower it and coil up the wire. Before getting underway, the antenna wires had to be restored back to normal. In many ports ships were not allowed to use their radio while in some ports, the radio room would literally be sealed.
The new result was the Radio Officer had nothing to do while a ship was in port so he was usually the first one down the gangplank and the last to return. Made a lot
of other shipmates jealous.
|In order preserve the historic appearance of the Brown's radio room, the ship's amateur radio station has been set up in this modest position in a small room adjacent and aft of the radio room. This is how it looked on August 6, 2000. (Photo by Jerry Proc)|