4 ms·

Handbook of Analog Computation [pdf]

78 points by dave9000 8y ago

usgroup 8y ago
Thank you for finding this ; I’m really grateful . I’ve been looking for a decent book on the topic . For those still tinkering with analog computers, could you recommend a setup for a beginner? Something that’d let me build real things that isn’t crazy expensive (and isn’t just a simulator). Is there something like a RPi for analog computing?
- Junk_Collector 8y ago
  So one of the neat things about Analog computers is that you get a lot of kick out of "simple" circuit designs. All you need to reproduce everything in the handbook is a bread board, a power supply, and an oscilloscope for output. You can get the individual components from Ada Fruit, Digikey, Mauser, and more. Depending on where you live you can even pick them up locally. Fry's and Microcenter being the two biggest chains that still stock opamps and the like. If you don't even want to hassle with all of that, then you can look into something like the Elenco electronic playground for $50 which has most of what you need mounted and then you just jumper, ala the old analog computers. If you wanted to get really advanced, you would want to go to something like the guys at https://www.xmicrowave.com/ https://www.xmicrowave.com/ make, but that gets awfully spendy on a hobby budget.
amelius 8y ago
I'd like to see an FPGA, but for analog circuits.
- ethhics 8y ago
  Like an FPAA? https://en.wikipedia.org/wiki/Field-programmable_analog_array https://en.wikipedia.org/wiki/Field-programmable_analog_arra...
  - philpem 8y ago
    I remember reading about the Anadigm FPAAs, but I don't recall finding anyone who sold them. The Cypress pSOC series is fairly similar (programmable analog blocks mated to a Cortex-M microcontroller core) and easier to find on sale. I'd argue that it's also more useful in modern mixed-signal designs.
- rusticpenn 8y ago
  There are several, however they arent as flexible as an FPGA. You have to search for FPAA.
TopHand 8y ago
The first computer I ever owned was an analog computer from Edmund Scientific. It was fundamentally an electronic slide rule. It had a meter that swung from a negative value to a positive value. The operator adjusted some potentiometers so that the meter was nulled. The output was read from the numbers pointed to by the knobs on the pots. At least that is the way I remember it working. I don't recall how exactly the equation was entered, but I think there were some pots for that too. As far as building your own analog computer, look at op amps. They're called that because they perform mathematical operations, such as summing, multiplying, and integration. Of course they do the inverse operations as well.
- sansnomme 8y ago
  With two op amps you can build a neural network. (Or at least a single perceptron) https://www.nutsvolts.com/magazine/article/the_perceptron_circuit https://www.nutsvolts.com/magazine/article/the_perceptron_ci...

78 points by dave9000 8y ago

Thank you for finding this ; I’m really grateful . I’ve been looking for a decent book on the topic . For those still tinkering with analog computers, could you recommend a setup for a beginner? Something that’d let me build real things that isn’t crazy expensive (and isn’t just a simulator). Is there something like a RPi for analog computing?

Junk_Collector 8y ago
So one of the neat things about Analog computers is that you get a lot of kick out of "simple" circuit designs. All you need to reproduce everything in the handbook is a bread board, a power supply, and an oscilloscope for output. You can get the individual components from Ada Fruit, Digikey, Mauser, and more. Depending on where you live you can even pick them up locally. Fry's and Microcenter being the two biggest chains that still stock opamps and the like. If you don't even want to hassle with all of that, then you can look into something like the Elenco electronic playground for $50 which has most of what you need mounted and then you just jumper, ala the old analog computers. If you wanted to get really advanced, you would want to go to something like the guys at https://www.xmicrowave.com/ https://www.xmicrowave.com/ make, but that gets awfully spendy on a hobby budget.

amelius 8y ago

I'd like to see an FPGA, but for analog circuits.

ethhics 8y ago
Like an FPAA? https://en.wikipedia.org/wiki/Field-programmable_analog_array https://en.wikipedia.org/wiki/Field-programmable_analog_arra...
- philpem 8y ago
  I remember reading about the Anadigm FPAAs, but I don't recall finding anyone who sold them. The Cypress pSOC series is fairly similar (programmable analog blocks mated to a Cortex-M microcontroller core) and easier to find on sale. I'd argue that it's also more useful in modern mixed-signal designs.
rusticpenn 8y ago
There are several, however they arent as flexible as an FPGA. You have to search for FPAA.

TopHand 8y ago

The first computer I ever owned was an analog computer from Edmund Scientific. It was fundamentally an electronic slide rule. It had a meter that swung from a negative value to a positive value. The operator adjusted some potentiometers so that the meter was nulled. The output was read from the numbers pointed to by the knobs on the pots. At least that is the way I remember it working. I don't recall how exactly the equation was entered, but I think there were some pots for that too. As far as building your own analog computer, look at op amps. They're called that because they perform mathematical operations, such as summing, multiplying, and integration. Of course they do the inverse operations as well.

sansnomme 8y ago
With two op amps you can build a neural network. (Or at least a single perceptron) https://www.nutsvolts.com/magazine/article/the_perceptron_circuit https://www.nutsvolts.com/magazine/article/the_perceptron_ci...