. The Bell System technical journal . ^ ^^^Y^ >r2r^ P^^ BEFORE AFTER .- «=^ CYCLOHEXANE ^ 1 ,^-;^:::::=^^ ^^=^ r^ ^ ^ ^ 45 50 0 5 10 15 20 25 30 35 40 TEMPERATURE IN DEGREES CENTIGRADE Fig. 10—Temperature variation of resonant frequency before and after add-ing weights to mounting wires. (or dilute polymer solution) is bothersomely small. An excellent oscillatorat 20 kc can hardly be expected to drift less than ±2 cycles, but at 20kc the A/ like that between the sets of curves on Fig. 10 might be only10 cycles, so 20 to 35 per cent error could come in. Hence, a differentscheme for measureme
. The Bell System technical journal . ^ ^^^Y^ >r2r^ P^^ BEFORE AFTER .- «=^ CYCLOHEXANE ^ 1 ,^-;^:::::=^^ ^^=^ r^ ^ ^ ^ 45 50 0 5 10 15 20 25 30 35 40 TEMPERATURE IN DEGREES CENTIGRADE Fig. 10—Temperature variation of resonant frequency before and after add-ing weights to mounting wires. (or dilute polymer solution) is bothersomely small. An excellent oscillatorat 20 kc can hardly be expected to drift less than ±2 cycles, but at 20kc the A/ like that between the sets of curves on Fig. 10 might be only10 cycles, so 20 to 35 per cent error could come in. Hence, a differentscheme for measurement of ju than that in earlier systems wasevolved. The tenth harmonic of the (say 80 kc) resonant frequency wasbeat against the 79th harmonic of a controlled standard 10-kc interpolation oscillator accurately readable to 1 cycle then suppliesthe many hundred (roughly 1000) difference between these two high 90,000 70,000 (^ 60,000m 2400 ^ h^^ — - BEFORE - AFTER A***- CRYSTAL IN^ CYCLOHEXANE (80 KC) A^ L w r ^^ ^^J kj. 10 15 20 25 30 35 40 TEMPERATURE IN DEGREES CENTIGRADE Fig. 11—Temperature variation of resistance at resonance before and afteradding weights to mounting wires. 336 THE BELL SYSTEM TECHNICAL JOURNAL. MARCH 1952
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Keywords: ., bookcentury1900, bookdecade1920, booksubjecttechnology, bookyear1
