How to select the right timing device—Part II
May 22, 2012 | Although quartz has a very low coefficient of thermal expansion, variation due to temperature change is still a large component in the frequency stability of quartz oscillators. Overall frequency stability of fixed-frequency quartz oscillators is ±20 to ±50 ppm without temperature compensation (See Figure 1). Resonators expand and contract due to changes in temperature, affecting their resonating frequency and making temperature compensation critical to oscillator performance for demanding applications. Table 1 compares the performance of silicon MEMS and quartz oscillators, considering many of the parameters discussed in Part 1. Comparison of silicon MEMS and quartz oscillators. In Part II, we go into more detail on several important concerns for high performance oscillators: temperature response, frequency
control and addressing EMI reduction. Part 1 of this article described basic requirements for timing devices and listed classes of oscillators for different applications. TEMPERATURE COMPENSATION.
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Quartz Heater?
May 13, 2008 by
Some types of electric heaters like "Quartz Heaters" are more efficient than old-fashioned electric heaters.
a) True
b) False
The answer is: b. Due to advertising, a lot of people think quartz heaters are more efficient, but it is not so. If you pay the electric power company for a kilowatt-hour of energy (and your meter is working right) you get a kilowatt-hour of energy, and if you feed the energy to a heater it turns it all to heat. If some of the energy were somehow wasted, ask yourself where it could go. A motor wastes energy as heat, but a heater can't make anything but heat.
Now a fan might spread the heat over a room more evenly or a reflector might focus the heat, but they have been on electric heaters for decades. So why are quartz heaters such a fad? The power of advertising.
I agree with BB's answer (B); efficiency, measured by total heat output, would be the same for both heaters. However, it's possible for a quartz heater to be less effective if any of its radiant power is directed toward a window where it could escape. My own experience is that radiant heat from a 1 or 2 kw heater isn't worth much unless you're pretty near it; a blown standard heater seems more useful in warming up a room. Heating the walls with radiant energy increases the heat loss rate compared to warmer air and colder walls.
How much power does a quartz heater use?
Dec 02, 2008 by Glyn
We've just got ourselves a little 2 x bar quartz heater but we're not sure how much power it will use for, say, 1 hour. Are they cheap to run? The back of the heater says '240v ~ 50Hz 800w'
Anybody be able to give us an idea?
Thanks =D