https://ieeexplore.ieee.org/document/8874589 Matt Undecided showed a photo of it.
Archive for the ‘Vacuum tubes’ Category:
2025-07-08 In 1929 The Superheterodyne Radios Made TRF Radios Obsolete
In the 1920s the TRF – tuned radio frequency – radios were hard to tune and their performance wasn’t very good. In 1929 the radio manufacturers started selling superheterodyne radios that had only one tuning knob, not several like the TRFs had. No more fiddling around with knobs to try to get good reception. Plus
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2023-11-27 RCA BFO Audio Oscillator Photos
Chuck commented about the audio oscillator being a BFO, and it reminded me that I’ve got an old RCA BFO audio oscillator stuck away in the garage. It was a cheap way of getting an audio sine wave that covered the full audio band without any switching. Nowadays it’s all done in sine and other
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2023-11-06 Reproduction Antique Radio Tubes and sets
I’ve been discussing the restoration of a hundred y.o. radio, and I thought about the retro light bulbs that look like incandescents but use LED filaments. Someone should make some old tubes that are actually using LEDs that look like the filaments, but just for decorative purposes. The glass envelope would look like the tube;
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2023-08-19 Electric Vehicle Batteries – What Happens To Them
Electric car batteries and all other lithium batteries are processed into ‘black mass’ at this Li-Cycle facility in Gilbert AZ. 95% of the batteries is recycled into inert, mostly plastic waste, copper and other heavy metals, and black mass where the lithium, cobalt and other valuable minerals are. The process starts with shredding the batteries
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2023-07-16 26H20 Radar Repair At Ft. Monmouth, NJ
In 1966 I completed basic training and went to Ft. Monmouth, NJ for 10 months of Radar repair training. The last half of the course we got to work on the actual Radars in *that* barn-like building in the photo. I was on the graveyard shift. There were birds flying around up in the rafters
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2017-12-04 Converting Tube Set to Transistors
From FB group Vintage Transistor Radios I’ve considered converting a tube set to transistors. The problem is getting tube bases that aren’t sharp and breakable glass. Some old electronics used tube base type plugs for relays and plug-in modules. Then there is the problem of dealing with the higher voltage. Transistors can handle 300V, but
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