Use of electron tubes today

Your information is very old. The military now have semiconductor equipment that is very robust and can take any Electromagnetic Pulse. The new equipment is properly designed and as much higher performance than what they can get with tubes. Tube equipment requires a large power source to operate.

There is a big market in tube equipment for musicians and diehard type audio files who like the sound better from tubes. This is a rather large industry in the audio file world. Tube equipment tends to be a higher in THD consisting of more of the odd harmonics. The clipping is less harsh when over driven. The noise floor is a little higher. This all attributes to giving the effect of a smoother sound.

On the other side of things, if you want a more accurate sound with less distorion, then a well designed solid state system is the better way to go. There are also audio files that prefer this to tube equipment. Also tube equipment requires higher maintenance. Tubes will wear out, and capacitors will tend to wear down faster from the heat.

Personally, I don't think tube equipment for audio applications will die out very soon.

Back then, a lot of stuff simply hadn't been turned over. The tube stuff was there because it was still useable and the cost of replacement was too high. A lot of military equipment was top of the line, so there was less incentive to move to better equipment.

Solid state elsewhere brought a lot of fancier technology down in cost. Direct frequency readout, synthesizer and such were prohibitive (due to size and cost) in tube equipment, but the military was willing to pay for it so they had it. When solid state made it cost effective, it gave the consumer that level of equipment at a price they could pay, so there was incentive for the consumer or hobbyist to abandon the tube equipment and move to solid state.

Note also that the early wave of solid state equipment was pretty lousy. At least some of it was solid state so it could be solid state. The designers hadn't figured out how to make good solid state equipment. I'm thinking especially of receivers, some/much of the early transistorized receivers for more than local broadcast stations were awful at handling strong signals. It took time before that was figured out, which brought things to the seventies. Add a few years for changeover, and that accounts for why tube gear was still in use "that late".

Transmitting was another matter. You could easily generate power with tubes, but doing it with solid state devices cost money. So even after a lot of transmitters had become solid state, their final stage or stages would be tubes, because it was cost efficient and there was little reason to not use them there.

As for the issue of EMP, that's been said of the Russians. But, it can also be argued, it has been argued, that one reason they lagged is because they didn't have the resources. They'd have to retool to move over to solid state, and if they tried to buy they might face restrictions. The tubes still worked, so they stuck with it.

If you read about the USSR's early "home computers", you'd find that they ended up copying the west, and in at least one case had to use a multiple set of ICs to duplicate a CPU that was in the west on one IC. So even by the eighties they were lagging, which does reinforce the notion that they kept with tubes because that was the state of their technology.

Michael

Some of the holdout tube users are musicians who have something they know works, and don't want to bother with finding a replacement. Guitar amps often do things that would be intolerable in a system used to _reproduce_ music. Some of the Cult of the Tube is just plain snobbery. The former Western Electric plant is still making type 300B tubes. There are enough customers to keep the old production line running. I'm sure that solid- state designs are available that beat the 300B on every measurable parameter, including its legendary soft clipping, but that doesn't impress people who buy something just *because* it's expensive. I understand that the infamous $480 wooden volume control knob is no longer offered, but there's plenty of other audiophoolery out there, like speaker-cable elevators. Anyone who thinks the minute reduction in shunt capacitance produece by raising your speaker cables a few inches from the floor, even if it's a conductive foor, haa never seen the impedance plot of his favorite speaker system.

BTW, before you say that your $1000 silver litz wire speaker cables sound different from 12-guage copper, are you sure your head was in *exactly* the same position as before you switched cables? Unless you listen in an anechoic chamber, a few inches can make an audible difference. Even if you were to set up a neurosurgeon's head-fixator frame to exactly reproduce your listening position, bending down to change your cables will change your heart rate and blood pressure, which is enough to subtly change your perceptions.