Friday, January 28, 2011

Receivers.

This is coolbert:

"Warning. Do not use
aboard ship. Unsafe radiation limits"

"it is built like a Tank and looks like
it belongs in the military supply depot."


From the previous blog entry regarding the Crosley Corporation and their manufacture of what were referred to as "morale receivers"!

The "morale receiver". NOT absolutely what I thought it was.

A radio receiver, manufactured during wartime with a specific intent, to provide "entertainment" for the military forces. Issued to and allowed the soldier, sailors, marines, airmen to "tune" the radio waves from the home front, listen to English language broadcasts, "Tokyo Rose", "Axis Sally", etc.

News from home, the usual general entertainment type of programming as was of the era. The television being a great rarity [scheduled programming did not even exist?] at the time, radio the main mass media "outlet" of the period.

Companies geared to the wartime effort, Crosley, E.H. Scott, etc., manufacturing these receivers for the military.

"The REP is a transformer-powered World War II era Navy morale receiver that can be switched to either 110 or 220 volts AC. It has 7 active tubes and sockets for 7 spares, including a socket for a spare 6E5 tuning eye. The receiver covers the AM broadcast band from 540 to 1610 KHz and two short wave bands from 5.8 to 15.8 MHz"





But a radio receiver with a glaring drawback as manufactured. Were dangerous to use aboard a naval or merchant marine vessel. ONLY to be used while anchored at port [?], the radio posing a danger to ships at sea from what are called spurious emissions!!

"the Navy was concerned that RF from a receiver's local oscillator could be picked up by enemy direction finders [DF]. This radio was obviously intended for shore-use only since it did not meet the rather strict low radiation standards."






"The E.H. Scott Morale Receiver is interesting in that it was the only receiver made during WW2 where radiation from the local oscillators were heavily suppressed. Up to that point, the Germans learned to DF a convoy by tuning into the signals given off by local oscillators. Some German subs could detect these signals from as far as 100 miles at night."

Right - - exactly! Those radio receivers of the time, tube sets, if NOT ADEQUATELY SHIELDED - - GAVE OFF WHAT ARE CALLED SPURIOUS EMISSIONS!! Signals that could be detected by skilled enemy radio operators at a distance, compromising possibly the location of an entire convoy, with the consequences often quite terrible!

A sailor - - careless - - using a "morale receiver" while at sea, could get his ship sunk and himself killed!

That figure of 100 miles would be a great rarity, a maximum range only under the most ideal of conditions? Nonetheless, these receivers if used in an improper manner, did constitute a danger that was recognized, proactive measures having been taken to ward off peril.

coolbert.

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