And what country can preserve its liberties if their rulers are not warned from time to time that their people preserve the spirit of resistance? Let them take arms. The remedy is to set them right as to facts, pardon and pacify them. What signify a few lives lost in a century or two? The tree of liberty must be refreshed from time to time with the blood of patriots and tyrants.
Wednesday, July 1, 2020
I still have some old vacuum tubes somewhere from a TV my parents had.
I have an original AM radio out of a 55 Chevy BelAir that is full of vacuum tubes. Been sitting on the work bench for a month playing the local station non stop like it was made yesterday.
Me too, Rob. My dad use to pull 'em out of our Dumont TV and head to the local Hardware store. He'd come back put the new tubes (valves in the UK) in and spend another 15 minutes looking into the mirror on a chair in front of the set adjusting the vertical & Horizontal hold.
IBM module was called cordwood stacking. The components would remind people of a wood pile. Yes, I am an old fart. Vacuum tube theory was so much easier to learn than solid state.
There's an amateur radio subculture which uses tube-type equipment. Some have old broadcast transmitters which were cast off when stations converted to solid-state. Google "amateur radio boatanchors" sometime. There are plenty of tubes out there but some which are popular with the audio community have become more expensive.
I have a stereo preamplifier powered by a pair of RK-34 tubes that long ago were used in Spitfire fighter plane radios. It was built by a guy who repairs and sells audio equipment in his small shop. He once built an amp that you could broil steaks over the power tubes on. Try that with an integrated circuit........
Many still swear that the best sound fidelity comes out of the old vacuum tube pre-amp's and amp's. I would like to compare to modern electronics, using modern speaker setups, but I suspect it's true. Digital degradation and noise is a real thing.
The coolest vacuum tubes I ever saw were the power tubes for the Calutrons at Oak Ridge National Lab that were used to separate uranium isotopes to get pure U-235. These tubes output 30kV (IIRC) and were about 3 feet tall and about 6-8 inches in diameter. The machines themselves were preparative mass spectrometers that were about 2-1/2 - 3 stories tall and had huge electromagnets in them. The tubes powered the ion source which converted the uranium tetrachloride into ionic clouds. And because copper was in such short supply due to the war effort, the electromagnets were made from iron cores wrapped in silver wire, which was obtained by converting the entire US silver reserve at Ft. Knox into wire. It was returned to Ft.Knox after the war. But I digress ...
I have an original AM radio out of a 55 Chevy BelAir that is full of vacuum tubes. Been sitting on the work bench for a month playing the local station non stop like it was made yesterday.
ReplyDeleteI remember pulling tubes from the TV and going down to the tester machine at the grocery store to find out which went bad and get a new one.
ReplyDeleteMe too, Rob. My dad use to pull 'em out of our Dumont TV and head to the local Hardware store. He'd come back put the new tubes (valves in the UK) in and spend another 15 minutes looking into the mirror on a chair in front of the set adjusting the vertical & Horizontal hold.
DeleteI have several vacuum tube radios around the house, and a box of spare tubes.
ReplyDeleteThat IBM tube assembly is often called the first integrated circuits. Not monolithic, but a subcircuit in the footprint of a tube.
IBM module was called cordwood stacking. The components would remind people of a wood pile. Yes, I am an old fart. Vacuum tube theory was so much easier to learn than solid state.
ReplyDeleteThere's an amateur radio subculture which uses tube-type equipment. Some have old broadcast transmitters which were cast off when stations converted to solid-state. Google "amateur radio boatanchors" sometime. There are plenty of tubes out there but some which are popular with the audio community have become more expensive.
ReplyDeleteI am part of that culture, and yes my Ameritron AL-811H has 4 tubes. I input around 70 watts and get around 900 out.
DeleteI have a stereo preamplifier powered by a pair of RK-34 tubes that long ago were used in Spitfire fighter plane radios. It was built by a guy who repairs and sells audio equipment in his small shop. He once built an amp that you could broil steaks over the power tubes on. Try that with an integrated circuit........
ReplyDeleteMany still swear that the best sound fidelity comes out of the old vacuum tube pre-amp's and amp's. I would like to compare to modern electronics, using modern speaker setups, but I suspect it's true. Digital degradation and noise is a real thing.
ReplyDeleteThe coolest vacuum tubes I ever saw were the power tubes for the Calutrons at Oak Ridge National Lab that were used to separate uranium isotopes to get pure U-235. These tubes output 30kV (IIRC) and were about 3 feet tall and about 6-8 inches in diameter. The machines themselves were preparative mass spectrometers that were about 2-1/2 - 3 stories tall and had huge electromagnets in them. The tubes powered the ion source which converted the uranium tetrachloride into ionic clouds. And because copper was in such short supply due to the war effort, the electromagnets were made from iron cores wrapped in silver wire, which was obtained by converting the entire US silver reserve at Ft. Knox into wire. It was returned to Ft.Knox after the war. But I digress ...
ReplyDelete