Category: history

Radio Caroline, 49 years after

Radio Caroline went on the air forty-nine years ago this weekend, broadcasting from the MV Caroline off the coast of England.  Why is this important?  Before offshore broadcasting was attempted, in Europe the only radio stations (and TV) were government owned.  As such, they had a monopoly over the airwaves and were very restrictive on which groups or types of music they allowed to be broadcast.  Many of the so-called “British Invasion” groups like The Beatles, Rolling Stones, The Who, The Kinks, etc got their first airplay on offshore radio stations like Radio Caroline or Radio London.

This video “Radio Caroline – A Day in the Life,” shows what it was like to be an offshore broadcaster:

By the haircuts and music, that appears to be sometime in the eighties.

Check out the Radio Caroline website for more information.  From 1983 onward, Radio Caroline was broadcast from the MV Ross Revenge. This is an overview of the Ross Revenge transmitter hold.  The movie “Pirate Radio” is loosely (very loosely, by most accounts) based on Radio Caroline/Radio London composite.

Radio London was one of the other well-known offshore radio ships.

I am sure that there are other tribute sites with lots of technical information on how they broadcast. Much of offshore radio was outlawed in the late 1960s by several European countries. Radio London signed off on August 14, 1967. Radio Caroline continued on in various iterations until about 1991 or so.

WBCQ is airing a radio ships special on Sunday, March 31, 2013, at 5,110 KHz starting at 6 pm Eastern daylight time (2200 UTC).

Restoration work on an RCA transmitter

I read through this article about the ongoing restoration work of an RCA SSB T-3 transmitter and found it interesting.  The RCA T-3 transmitter is a 20 KW SSB/ISB HF (2-28 MHz) unit designed for point-to-point telephony service.  Because SSB requires class A or AB low distortion amplifiers, this is a large unit, even for its age and power levels.

From the looks of the before pictures, this transmitter was in sorry shape.

Here is a brief video of the transmitter start-up:

These units were designed to be switched on and run at 100% duty cycle for most of their operating lives. That is some heavy iron there.  This particular unit was made in 1959. More here and video part 2:

Anyway, before geosynchronous satellites, HF point-to-point transmitters were used to make long-distance phone call connections and send data and pictures back and forth over long distances. Out in Hicksville, Long Island, Press Wireless ran a data and fax system that used HF for long-haul data transmission.  Much of the WWII reporting from Europe and the Pacific Theaters was carried over this system.

Text would be printed out on a mechanical teletype machine at something like 60 words per minute, which was considered fast for the time:

Tuning across the band, one can often hear Radio Teletype (RTTY or RATT) which uses a 5-bit Baudot code, 170 Hz shift with 2125 HZ representing a Mark or 1 bit and 2295 Hz representing a Space or 0 bit, which is a bit different from the Bell 103 modem specifications. This is what it sounds like at 75 Baud:

So slow you can almost copy that by hand.

The RCA H (SSB T-3) unit above was independent sideband (ISB), which means that either sideband or both could be modulated independently of the other, thus two channels of information could be transmitted.  SSB bandwidth is about 2.7 KHz, which is good for telephone-grade audio or low-speed data.

I sort of wish I was living in California again, I’d lend a hand.

Call Sign Trivia

I found this youtube video about Pittsburgh, Pennsylvania radio stations:

That’s cool and all that, but it brings up the question about the K/W calls which were misplaced during the early days of broadcasting.  Originally, call letters were assigned to ships and coastal radio stations in the following way:

Three-letter call signs were for coastal (land) stations.  K letter calls were for shore stations in the west and W letter calls were for shore stations east.  Ships were assigned four-letter calls, W calls signs were issued to ships homeported on the west coast and K calls for ships homeported on the east coast.  There was a period of time when a few K call letters were issued to east coast broadcasting stations, no one is quite sure why.  Prior to 1923, the K/W boundary was not the Mississippi River, but the eastern border of the states of Montana, Wyoming, Colorado, and New Mexico.  Thus, there are many more misplaced W call signs than K call signs.

Of course, KDKA and KQV come to mind. Philadelphia has KYW. What other misplaced call signs are there, e.g. W’s west of the Mississippi and K’s to the east?  Of course, one can google it and get an answer, however, there is one that is pretty obscure.

WKNR 1310; gone but not forgotten

Reflecting the state of the economy in Detroit, WDTW went silent on January 1st. Less than two weeks later, the towers come down:

Thanks, Chris R for the video link.

The license has been donated by Clear Channel to MMTC (Minority Media and Telecommunications Council), but not the land or towers. It remains to be seen whether the station will return to the air, however, given the costs involved and the economic conditions in Detroit, that is unlikely.

The station signed on in 1946, moving to 1310 KHz with full-time operation in 1948.  Back in the day, it was a flame-throwing top 40 station and is purported to be the source of the “Paul is dead” rumors that surrounded the Beatles in the late 60’s.  Much more history at Keener13.com.

Take pictures of your favorite AM stations now because tomorrow, they and all their history may be gone.