I looked at those in the Heathkit catalog when they were still being sold but never really wanted one. I'm a programmer so I need a computer that has enough memory to write a significant program. That's why the ET-3400 didn't work out for me, I think there was a memory expansion available for it but even that only brought it up to 1K as I recall.
I looked at those in the Heathkit catalog when they were still being sold but never really wanted one. I'm a programmer so I need a computer that has enough memory to write a significant program. That's why the ET-3400 didn't work out for me, I think there was a memory expansion available for it but even that only brought it up to 1K as I recall.
I did 32K of static RAM expansion on my ET-3400 with battery backup.
I looked at those in the Heathkit catalog when they were still being sold but never really wanted one. I'm a programmer so I need a computer that has enough memory to write a significant program. That's why the ET-3400 didn't work out for me, I think there was a memory expansion available for it but even that only brought it up to 1K as I recall.
I did 32K of static RAM expansion on my ET-3400 with battery backup.
Nice! Did you make a kit that I can buy from you to expand mine?
I looked at those in the Heathkit catalog when they were still being sold but never really wanted one. I'm a programmer so I need a computer that has enough memory to write a significant program. That's why the ET-3400 didn't work out for me, I think there was a memory expansion available for it but even that only brought it up to 1K as I recall.
I did 32K of static RAM expansion on my ET-3400 with battery backup.
Nice! Did you make a kit that I can buy from you to expand mine?
I used a 30- ns cache chip that was for a 486 mother board. I can't put my finger on it. just closed on my house and every thing is in boxes in storage.
I looked at those in the Heathkit catalog when they were still being sold but never really wanted one. I'm a programmer so I need a computer that has enough memory to write a significant program. That's why the ET-3400 didn't work out for me, I think there was a memory expansion available for it but even that only brought it up to 1K as I recall.
The EC-1 was an analog computer. It didn't have "memory" and you didn't write "programs" for it at all, you selected appropriate feedback components for the op-amp circuitry so that the output voltage would settle to the solution which was required to solve the equation encoded by the circuit wiring and feedback values for the given inputs.
I looked at those in the Heathkit catalog when they were still being sold but never really wanted one. I'm a programmer so I need a computer that has enough memory to write a significant program. That's why the ET-3400 didn't work out for me, I think there was a memory expansion available for it but even that only brought it up to 1K as I recall.
The EC-1 was an analog computer. It didn't have "memory" and you didn't write "programs" for it at all, you selected appropriate feedback components for the op-amp circuitry so that the output voltage would settle to the solution which was required to solve the equation encoded by the circuit wiring and feedback values for the given inputs.
That's my point exactly. No ability to program it at all. The ET-3400 was only slightly better with 256 bytes of memory.
Was in need of some repair: the two pots for balance and volume are duals, and each were terribly out-of-tolerance. So I hardware a couple fixed resistors in place for the balance pot, and then dangled a dual volume pot through the front panel.
After in use for a couple months, the output level dropped significantly. Found a "popped" electrolytic in the voltage doubling circuit that powers the preamp section. Then, after another few months, two electrolytics in the power amp supply filters popped.
Interestingly, the circa '72 AA-1214 that I built has had no components replaced. Not saying there's no need; I'm sure some of the electrolytics could stand to be retired!
Noisy potentiometers and bad electrolytic capacitors were two of the most common problems on a lot of the older analytical and imaging equipment I looked after. A small battery powered amplifier with a capacitor on the input and speaker was good for testing both.
Comments
I did 32K of static RAM expansion on my ET-3400 with battery backup.
I didn't build it, but it seems to work fine. I don't have a use for it.
These seem to be going for $40 or more on ebay. I'd rather it go to someone on these forums instead.
*Just pay shipping...
I used a 30- ns cache chip that was for a 486 mother board. I can't put my finger on it. just closed on my house and every thing is in boxes in storage.
The EC-1 was an analog computer. It didn't have "memory" and you didn't write "programs" for it at all, you selected appropriate feedback components for the op-amp circuitry so that the output voltage would settle to the solution which was required to solve the equation encoded by the circuit wiring and feedback values for the given inputs.
Was in need of some repair: the two pots for balance and volume are duals, and each were terribly out-of-tolerance. So I hardware a couple fixed resistors in place for the balance pot, and then dangled a dual volume pot through the front panel.
After in use for a couple months, the output level dropped significantly. Found a "popped" electrolytic in the voltage doubling circuit that powers the preamp section. Then, after another few months, two electrolytics in the power amp supply filters popped.
Interestingly, the circa '72 AA-1214 that I built has had no components replaced. Not saying there's no need; I'm sure some of the electrolytics could stand to be retired!