I’d like to see a solar-powered computer composed primarily of nuvistors and other nuclear hardened parts. Maybe it could survive nuclear holocaust and be an oracle for some future tribe.
"Valves" had always been a mystery to me. When I began to really get into electronics, vacuum tubes were a kind of distant echo from my childhood that I barely remembered. As a kid I remember staring into the back of the small B&W television we had when I was young — the insides looking to me like some kind of Things to Come cityscape in miniature — all lit with orange neon. And there too was the ubiquitous "tube tester" in the Rexall Drug Store (looking somewhat like a prop from perhaps Lost in Space).
As an adult Thomas J. Lindsay’s books on building small regenerative vacuum tube receivers caught my attention — I also got caught up in building both tube-based guitar amplifiers and hi-fi audio amplifiers. These allowed me to dive into tubes and finally learn about them — you know, posthumously as it were.
After initially thinking that tubes were probably inferior in all ways to solid-state, I came to find them to still be very capable and even arguably better — at least with regard to sound amplification. Somehow too I had imagined in my mind they were outrageously dangerous to work with — thousands of volts — and assume,ed they were fragile and quick to "burn out".
The circuit I used however never went over 300 or so volts (to be sure, you still need to be careful with these circuits in a way you may not be familiar with if Arduino circuits are all you know).
The tubes have never seemed to burn out for me — even after one or two amps have been my "daily drivers" for well over a decade (two decades?) now. Perhaps other circuits used less capable tubes or pushed them to their limits? Perhaps other enclosures like TV's did not allow adequate ventilation? I don't know.
And as for fragility — I mean they are glass, but the tubes I used in my hi-fi amps were NOS from WWII bomber radios. They seem to hold up to a good deal of bouncing around.
The Lafayette HA460 6M AM transmitter used a 6CW4 Nuvistor as a preamp. Mine survived a lightning strike to my 6M beam, which melted the Gamma Match and destroyed the front end harmonics filter. All tube, expect for a set of DC inverter transistors that allowed for mobile operation. Relatively good RF sensitivity for an AM rig of the era.
Gingerly repaired it served me many years in the late 1960's and still sits in the shack. Sporatic-E was strong in those days, to the extent you could easily DX low channel TV channels cross country. I turn it on every few months for 10-15 minutes in an attempt to keep the electrolytic capacitors polarized.
I put my electronics lab in mothballs over 10 years ago but up until the end my main audio scope was an HP from the 1970's that was all solid-state, except for the Nuvistor on each channel's input.
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[ 5.2 ms ] story [ 22.3 ms ] threadthat is one of the few domains where valve technology still holds a superior position, in terms of product lines
As an adult Thomas J. Lindsay’s books on building small regenerative vacuum tube receivers caught my attention — I also got caught up in building both tube-based guitar amplifiers and hi-fi audio amplifiers. These allowed me to dive into tubes and finally learn about them — you know, posthumously as it were.
After initially thinking that tubes were probably inferior in all ways to solid-state, I came to find them to still be very capable and even arguably better — at least with regard to sound amplification. Somehow too I had imagined in my mind they were outrageously dangerous to work with — thousands of volts — and assume,ed they were fragile and quick to "burn out".
The circuit I used however never went over 300 or so volts (to be sure, you still need to be careful with these circuits in a way you may not be familiar with if Arduino circuits are all you know).
The tubes have never seemed to burn out for me — even after one or two amps have been my "daily drivers" for well over a decade (two decades?) now. Perhaps other circuits used less capable tubes or pushed them to their limits? Perhaps other enclosures like TV's did not allow adequate ventilation? I don't know.
And as for fragility — I mean they are glass, but the tubes I used in my hi-fi amps were NOS from WWII bomber radios. They seem to hold up to a good deal of bouncing around.
Gingerly repaired it served me many years in the late 1960's and still sits in the shack. Sporatic-E was strong in those days, to the extent you could easily DX low channel TV channels cross country. I turn it on every few months for 10-15 minutes in an attempt to keep the electrolytic capacitors polarized.