"Robert A. Heinlein - Have Space Suit Will Travel" - читать интересную книгу автора (Heinlein Robert A)"Oscar, you're all right," I told it. "You and I are partners. We're going
places." I would have sneered at five thousand dollars for Oscar. While Oscar was taking his pressure tests I worked on his electrical and electronic gear. I didn't bother with a radar target or beacon; the first is childishly simple, the second is fiendishly expensive. But I did want radio for the space-operations band of the spectrum -- the antennas suited only those wavelengths. I could have built an ordinary walkie-talkie and hung it outside -- but I would have been kidding myself with a wrong frequency and gear that might not stand vacuum. Changes in pressure and temperature and humidity do funny things to electronic circuits; that is why the radio was housed inside the helmet. The manual gave circuit diagrams, so I got busy. The audio and modulating circuits were no problem, just battery-operated transistor circuitry which I could make plenty small enough. But the microwave part -- It was a two-headed calf, each with transmitter and receiver -- one centimeter wavelength for the horn and three octaves lower at eight centimeters for the spike in a harmonic relationship, one crystal controlling both. This gave more signal on broadcast and better aiming when squirting out the horn and also meant that only part of the rig had to be switched in changing antennas. The output of a variable-frequency oscillator was added to the crystal frequency in tuning the receiver. The circuitry was simple -- on paper. But microwave circuitry is never easy; it takes precision machining and a slip of a tool can foul up the impedance and ruin a mathematically calculated resonance. Well, I tried. Synthetic precision crystals are cheap from surplus gear. And I made it work, after the fussiest pray-and-try-again I have ever done. But the consarned thing simply would not fit into the helmet. Call it a moral victory -- I've never done better work. I finally bought one, precision made and embedded in plastic, from the same firm that sold me the crystal. Like the suit it was made for, it was obsolete and I paid a price so low that I merely screamed. By then I would have mortgaged my soul -- I wanted that suit to work. The only thing that complicated the rest of the electrical gear was that everything had to be either "fail-safe" or "no-fail"; a man in a space suit can't pull into the next garage if something goes wrong -- the stuff has to keep on working or he becomes a vital statistic. That was why the helmet had twin headlights; the second cut in if the first failed -- even the peanut lights for the dials over my head were twins. I didn't take short cuts; every duplicate circuit I kept duplicate and tested to make sure that automatic changeover always worked. Mr. Charton insisted on filling the manual's list on those items a drugstore stocks -- maltose and dextrose and amino tablets, vitamins, dexedrine, dramamine, aspirin, antibiotics, antihistamines, codeine, almost any pill a man can take to help him past a hump that might kill him. He got Doc Kennedy to write prescriptions so that I could stock Oscar without breaking laws. When I got through Oscar was in as good shape as he had ever been in Satellite Two. It had been more fun than the time I helped Jake Bixby turn his heap into a hotrod. |
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