vco's

[croyleje]

how about something on voltage controlled oscillators especially something about making your own i have tried a couple but  they never reach there upper end calculated valves never makes to the top end

also love the soldering re-ball idea

[Rerouter]

about VCO's just remember, jellybean op amps are far from ideal, your expected 0-5V output on an op amp might be 0.2-4.8 and same for the input, and you must compensate for that,

also some capacitor types shift in capacitance for a change in frequency,

[Zero999]

You need to provide more information: schematic, frequency range, desired waveform, topology etc.

[ThijssjihT]

Bumb, because I would like a vco video too

- How does it work?
- What calculations can you do?
- How to design your own vco?

[retrolefty]

Bumb, because I would like a vco video too

- How does it work?
- What calculations can you do?
- How to design your own vco?

 While the MC1648 chip is very dated, it's datasheet gives a lot of practical and theoretical background on VCO theory and design.

[AF6LJ]

This is a very broad subject.
You would want to break it down into varactor and non-varactor tuned VCOs.

[G0HZU]

I've designed a few VCOs for professional use but this was way back in the 1990s. Some narrowband and some wideband at frequencies up to a couple of GHz.

I've since designed a few up to about 7GHz for test fixtures but these days many people just buy ready made VCOs from Mini Circuits or Zcomm or they buy cheaper 'integrated' VCOs.

At work, we stopped designing our own VCOs because the NRE costs were so high. They require a lot of design effort and a lot of testing across temperature and vibration. For professional design it's generally much cheaper (overall) to just buy premade VCO units unless the product is very high volume.

To do a decent tutorial on VCO design up at UHF would require a lot of input from the person making the video and I think relatively few people would need to know/absorb this level of info anyway.

There are plenty of books on this subject and that's probably the safest way to learn this stuff (for those that want to learn VCO design in detail using modern simulation techniques etc).