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Author here. Sure, there are lots of ways to tell the history of computers, because lots of different lines of development fed into their creation. I hint at th

Author here. Sure, there are lots of ways to tell the history of computers, because lots of different lines of development fed into their creation. I hint at this in the prologue. But I chose to highlight one particular aspect (the origins of the basic components used to build digital computers - relays, tubes, and transistors). This naturally downplays the importance of IBM relative to other possible ways of telling the story. There's a mea culpa somewhere in the footnotes about the neglect of IBM.

deleted 5y ago
[deleted]
ghaff 5y ago
The switch theme is really interesting because I've been thinking about it in the context of quantum--qubits--recently. There's nothing really inherent that makes binary logic rather than ternary logic or analog inherently superior. It just turns out that making on-off switches has historically been relatively easy and cheap. I plan to read the book.
- Animats 5y ago
  Binary logic is usually composed of analog amplifiers designed to quickly hit some upper limit and saturate. In the off state, little power is dissipated, because current flow is tiny. In the on state, little power is dissipated, because resistance is low. In between, the "linear region", is where heat is generated. The goal is usually to spend as little time in the linear region as possible.
- klyrs 5y ago
  Most qubit designs use high- and low-energy states to encode binary values. In that regime, there is a reason to avoid 3-level systems: the energy gaps are hard to tune, and controlling the coupling between them is even harder.
Animats 5y ago
On the basic component end, the history of early electronics was a search for gain. Modern components have so much gain you can throw much of it away to make digital switches or negative feedback amplifiers. Early electronics struggled to get enough gain to drive headphones. Lack of good amplifiers limited the range of long distance telephones. There's a whole history of forgotten attempts to get some gain. Edison's electromotograph. (See if you can find out how that works. Edison discovered variable friction depending on electric current, but the physics wasn't understood until the 1960s or so.) A speaker driver pushing against a carbon microphone (early Bell System long distance). Higher power devices included magnetic amplifiers (the UNIVAC Solid State computer used those) and large Ward-Leonard drives, used for elevator control for many decades. There was a long struggle on the transmit side of radio to get gain at high power. The Alexanderson alternator, a high frequency AC generator, was the first real success. There's a long history of transmitting tubes, finally maxing out in radar systems for the DEW line that had tubes with their own vacuum pumps. Another kludge was the super-regenerative receiver, where positive feedback was used to run the same signal through the same stage more repeatedly. Noted for producing loud squealing sounds. There's also some history on the musical side. Look up the Teleharmonium, a musical instrument the size of a building. One was actually built. Lacking an amp, they had a sizable AC generator for each note. There's also the switchgear used in large pipe organs, with both electrical and pneumatic components. Those were workarounds for not having enough gain. We're spoiled today. You can hold the semiconductors used for controlling a locomotive's power in your hand. The first half of the 20th century, though, was a struggle to get enough gain to get anything done.
davidgould 5y ago
I particularly liked the way the series covered the way science and engineering progresses, through the almost blundering interaction of geniuses, cranks, fast buck artists, and bureaucrats over time.

deleted 5y ago

[deleted]

ghaff 5y ago

The switch theme is really interesting because I've been thinking about it in the context of quantum--qubits--recently. There's nothing really inherent that makes binary logic rather than ternary logic or analog inherently superior. It just turns out that making on-off switches has historically been relatively easy and cheap. I plan to read the book.

Animats 5y ago
Binary logic is usually composed of analog amplifiers designed to quickly hit some upper limit and saturate. In the off state, little power is dissipated, because current flow is tiny. In the on state, little power is dissipated, because resistance is low. In between, the "linear region", is where heat is generated. The goal is usually to spend as little time in the linear region as possible.
klyrs 5y ago
Most qubit designs use high- and low-energy states to encode binary values. In that regime, there is a reason to avoid 3-level systems: the energy gaps are hard to tune, and controlling the coupling between them is even harder.

Animats 5y ago

On the basic component end, the history of early electronics was a search for gain. Modern components have so much gain you can throw much of it away to make digital switches or negative feedback amplifiers. Early electronics struggled to get enough gain to drive headphones. Lack of good amplifiers limited the range of long distance telephones. There's a whole history of forgotten attempts to get some gain. Edison's electromotograph. (See if you can find out how that works. Edison discovered variable friction depending on electric current, but the physics wasn't understood until the 1960s or so.) A speaker driver pushing against a carbon microphone (early Bell System long distance). Higher power devices included magnetic amplifiers (the UNIVAC Solid State computer used those) and large Ward-Leonard drives, used for elevator control for many decades. There was a long struggle on the transmit side of radio to get gain at high power. The Alexanderson alternator, a high frequency AC generator, was the first real success. There's a long history of transmitting tubes, finally maxing out in radar systems for the DEW line that had tubes with their own vacuum pumps. Another kludge was the super-regenerative receiver, where positive feedback was used to run the same signal through the same stage more repeatedly. Noted for producing loud squealing sounds. There's also some history on the musical side. Look up the Teleharmonium, a musical instrument the size of a building. One was actually built. Lacking an amp, they had a sizable AC generator for each note. There's also the switchgear used in large pipe organs, with both electrical and pneumatic components. Those were workarounds for not having enough gain. We're spoiled today. You can hold the semiconductors used for controlling a locomotive's power in your hand. The first half of the 20th century, though, was a struggle to get enough gain to get anything done.

davidgould 5y ago

I particularly liked the way the series covered the way science and engineering progresses, through the almost blundering interaction of geniuses, cranks, fast buck artists, and bureaucrats over time.