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Eric
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2 hours ago, Eric said:

4DAB819D-AB3A-4024-B49B-7EC0DF58C38D.jpeg

Tubes sure made things big.

My receiver on my minesweeper was state of the art for the Navy in 1958.  The tubes were glass about 5/16 of an inch in diameter and maybe 2 inches long with wire leads out of the glass envelope.

This was about the most compact tube receiver available at the time.  It covered 500 KHz to 30 Mhz in one continuous microfilm dial projected onto a frosted glass face on the panel.  10 Khz markers were about 1/8 inch apart.

It was about the size factor of the Collins KWM series of later on.  It was in a case that was firmly bolted to a steel desk which was also bolted to the ship deck.

When at sea, if you zero beat a cw signal, it would slowly swing from zero beat to about 200 Hz and back again as the ship rolled in the waves or groundswells.  The stress on the ship actually twisted the receiver mounting very slightly, causing the variation in zero beat.

Just late night ramblings.

 

As long as I started, the Trransmitter was capable of 1 Kilo Watt output but set to 125 Watts for shipboard use.  I learned the design of the transmitter while it was being installed and when we went to sea, ours put out 1 KW from a 4-400 Tube final.  With a non-Navy antenna, I could communicate around the world from anywhere.

The transmitter was a monstrosity.  It was tubes.  It used harmonic addition and multiplication to achieve 1 MHz to 30 MHz in 10 Hz steps.  Yes, you read that right.  It had a digital dial and the variable frequency oscillator was a rack panel about 20 inches high and filled with small chassis harmonic generators and multipliers.  It all started with a 100 KHz crystal oscillator.  No variable frequency oscillators at all. It was a math nightmare.

It took me a while to understand the design.  It was a last effort for digital tuning using analog systems.

Edited by janice6
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2 hours ago, M&P15T said:

Wearing a suit in Florida heat & humidity.

Jeeeeeze, but people must have stunk back then.

I believe I read that they also thought that bathing too often was injurious to their health.

"...Today we place high value on personal hygiene but back in the day people could go from cradle to grave without ever immersing themselves in water. Many people believed that bathing was unhealthy and that soaking in water, especially hot water, would let disease enter the body. Even if you did decide to take a bath, you would not even have contemplated taking off your clothes – a habit that remained right through to the end of the 19th century!...",  https://listverse.com/2012/10/22/10-revolting-facts-about-the-18th-century/

 

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