I absolutely doubt this chip could be used reliably.
For one it has far too much noise so you can expect that clean output to be non-existent and for two if it is controlled by a resistor anything outside of a high quality <%1 tolerance will give you a drift that will cover kHz with temperature change.
I would take a close look at the datasheet. These look quite useful for there intended purpose but as a HF VCO they appear useless from what I have read.
Not to damper your inquiry but I would look into other alternatives.
Nothing beats a real VFO using the proper selection of temperature compensated capacitors with an FET front end and buffer. Problem is that requires some serious engineering to deal with drift compensation which most people don't want to mess with. Alternatives often are the easier choice like a DDS, or PLL, but those also share their own set of problems with spectrum output.
Sadly there is no easy alternative to vibrating a rock, and when you do it requires its own special circuitry outside of a transmitter if you want to do it properly.
Here is a VFO I have been working on with some good success...
http://darkliferadio.proboards.com/thread/833/shortwave-vfo-projectI need to update the post but so far I have added proper low pass filtering and a final PA stage to get it up to 100mw output with harmonics down to the floor and no spurs. Harder to achieve that sometimes with a DDS.
Just sharing to give you an idea of the work involved in literally reinventing the wheel. If you have the money and source it is stupidly easy to just go with a quarts crystal.
Topic: LTC1799 (Read 5361 times)
