Oscillators - Insights

The direct digital oscillators enabled much smaller and smarter oscillators. Also improvement in the materials used for the manufacture enables more stable oscillators with much better thermal characteristics.

General telecommunication technologies and GPS Technologies are popular applications and they define future needs. Trend is to go smaller by keeping same or better performance.

Optic fibre delay line oscillators High Q printed resonators (see the many patents by Ulrich Rohde) Active cancellation of noise and thermal drift.

CTS corporation, International Crystal Manufacturing (ICM) Company USA, Q Tech Corporation, Valpey Fisher, Raltron Electronics

Vectron, Rakon, CTS on the high end. Epson, NDK doing well on low to mid.

FOX, Abracon, Citizen, Aker.....

Years ago, built a cb radio oscillator. just for experimental purposes. It worked for communication about .25 of a mile. (1/4 of a mile) . Also assembled a heathkit dip meter which included a oscillator. These 2 experiences are all the hands on oscillator experience I have had. Have also read a moderate amount about them.

I have designed and built high precision PLLs which have exacting requirements on oscillators. I have also built temperature controlled crystal oscillators used in cable television block converters. For example, a frequency converter that converts a television channel, say channel 5, into channel 6.

I used RF oscillators making experiences of transmission of RFs ignals, I used local oscillators in several receiving systems as mixers. I used oscillators when studying the PLL technics and so on. Also I used low frequency oscillators that I applied in mu practical studies.

A futuristic use of high power oscillators is that it can be used as "energy transmission" career instead of cables or wires in conjugation with highly directive non dispersive antennas.

Was aware years ago, of some one using a oscillator for some purposes of receiving signals; the oscillator was about 66.6667 mhz or something very close to that.

Producing "arithmetic" and "geometric" spectral distribution COMB generators. I wish to be hired by a US company to continue developing these COMB generators.

Yes, one product was designed with a cheap OCXO that met the spec for temperature drift when delivered but one year later was so far out of spec that hundreds of oscillators had to be changed in the field at huge expense to the company and its reputation. So a cheap device was not so cheap at all in the end!

Yes. The clock oscillators used in the digital portion of the system interfering with the sensitive front end of RF receivers leading to the de sensing of the system there by reducing considerably the aerial range, which may ultimately lead to altogether scrapping of the system.

When you have two or more devices and you require that they are activated at the same time, if you do not use an oscillator to synchronize them, then the devices will not be activated correctly.

Frequency Stability. Isolation from external loading (Buffer). Independent Analog, and Digital Outputs. Amplitude Stability. Insensitive to reasonable temperature variation. Insensitive to reasonable Supply Voltage variation. Variable and Fixed Frequency construction options. Low external component count. Separate Power Ground and Signal Low, or Ground. Dual In-Line Package. Low Cost. Ready Availability. Application Notes with typical circuits illustrated.

A SMD wideband low phase noise voltage controlled oscillator working from 700MHz to around 2500 MHz with low distortion sine wave output which can be tuned over the full band by a relatively low voltage.

An inexpensive programmable VCO in the 1Ghz. to 5Ghz. range with built in PLL, prescaler and programmable counter. Parallel programming would be good for experimenting.

Be very careful to filter tuning line noise adequately and eliminate 'ground bounce' on ground planes near the tuning port if you want to achieve full performance from an oscillator. The same goes for the supply rail which should always be very adequately decoupled and run from a very low noise regulator - not the usual regulator you use for your digital circuits. Read up about 'phase hits' and decide whether these will effect your application and whether your oscillator is using a design that has good resistance to these effects.

Many people just only care of the frequency they want but seldom pay any attention to the waveform or the amplitude of the oscillator, which can lead to undesirable side effects often leading to interference with other sensitive parts of the system.

Cheap is not always best for consumer apps. Inferior quality can be costly in terms of time, waste, and reputation. Avoid over specifying performance. All specs must be tested too and this drives up cost.

Oscillators can be a two way sword . An oscillator can do the designed primary job satisfactory but at the same time show some undesirable characteristics like unintended radiations which can compromise the integrity of the system. So we should be careful in selecting the oscillator.

It's important to see what final application really request and to make sure supplier really can supply such device. Test data are very important for key parameter and it's better to ask some more questions and to get written confirmation than to look only to lowest price.

Before you start design and development, check how long the product will be manufactured. Discontinuance of a product, without recourse to an alternative, will cause great frustration.