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View Full Version : 700Mhz To 3.2GHz Crystal


MRClark32493
May22-10, 07:20 PM
I am attempting to construct a device that will vary frequency between MHz and 3200MHz. Does anyone know of a fairly inexpensive crystal that will allow me to use all frequencies in this range? Thanks
~Matt

vk6kro
May22-10, 07:52 PM
Crystals are usually used for single frequency applications, although they can be pulled over a small range of frequencies.

You may need a voltage controlled oscillator "VCO", although they are not likely to cover such a wide range of frequencies, so you may need more than one.
Have a look on Google or see the following:

http://www.spectrummicrowave.com/vcos.asp.

There are some signal generators that give this sort of output but they are usully pretty expensive

It also depends on the power level you need. VCOs are generally quite low powered devices.

You should also be aware that microwave circuits have very critical layouts and many normal components behave quite differently at these frequencies. An inch of wire can make a circuit stop working and capacitors behave like inductors.

waht
May22-10, 11:27 PM
Oscillators in microwave frequency range are difficult to design and construct, especially with a wide tuning range. Check out ready made mini-circuit VCOs www.minicircuits.com, or RF Bay www.rfbay.com