I need a varible oscillator

[stargate3216]

I need a varible oscillator with the largest range possible. What is the easiest way to get one? Build it? Buy it?

Please help.

 

[RadioRon]

The easiest way to get one is:

- borrow one (school, company, buddy)
- buy one (ebay or local store)

and the very hardest way is to build one. (much harder and much longer time, and not necessarily cheaper)

 

[stargate3216]

The easiest way to get one is:

- borrow one (school, company, buddy)
- buy one (ebay or local store)

and the very hardest way is to build one. (much harder and much longer time, and not necessarily cheaper)

I've been looking on the internet, but I have been totally unsuccessful.

 

[RadioRon]

What frequency range do you need? What output amplitude do you want?

 

[stargate3216]

What frequency range do you need? What output amplitude do you want?

It is going into a EM detentor/recivor, so I don't care about the amplitude.

Lets say, 30 Hz to 300 GHz. The entire radio wave section of the EM spectrum. Would that even be possible?

 

[stargate3216]

Now that I think about it, 30 Hz isn't going to work. I'll need a 20-mile-long antenna. Let's make it 3 KHz to 300 GHz.

 

[RadioRon]

You should care about the amplitude. If you don't, then 0 volts is OK, right? But seriously, if it is going into an EM receiver (I take that to mean a threat receiver, something useful for sensing radar and other forms of electromagnetic warfare threats) through a wire connection, you will want the ability to fine tune the amplitude. That is of course, unless your intention is to simply jam it, in which case a lot of ampitude is needed.

In any case, your search will not turn up much of anything, since variable oscillators do not exist that cover the frequency range you want in only one box. It will be necessary to have several oscillators, one for 3KHz to about 1 MHz, another for 1 MHz to about 3 GHz, another for about 3 GHz to about 20 GHz and perhaps one more for the rest of the range. If you intend to generate one steady signal at a time, these different oscillators can be joined together via a control bus and put under the command of a PC that manages which one is turned on and when. In this way, you can create a single system that does what you want. But it will cost a few dollars thats for sure. Still interested?

Perhaps its time to ask our favorite question which is... what exactly do you want to do? Please explain in detail.

 

[Hero999]

300GHz, lol that's less than a milimeter!

I don't even know if that's possible with a twt amplifier or klystron, it migh only be possible using a purpose built IC.

Think about it as a general rule an oscillator needs to be much smaller than the wavelength it generates, good luck with your 300GHz oscillator.

3GHz is probably as high as you can go with SMT parts and it won't be vary stable either. Your best bet is to make a VCO then a PLL to multiply up a much lower frequency generated from a more stable source.

 

[stargate3216]

What I am trying to do is make a radio scanner that can scan huge sections of the radio spectrum.

 

[RadioRon]

What I am trying to do is make a radio scanner that can scan huge sections of the radio spectrum.

Well, I hate to be a spoilsport, but I am getting the feeling that this is well beyond your capabilities. Making any radio receiver is challenging, but making one with huge frequency range is only for seasoned experts indeed.

 

[ThermalRunaway]

Basically, what Radio Ron is saying is that going back to your first question... it would be better to buy it.

300Ghz though?!?!

It's unusual for someone to want to scan the entire RF spectrum. Normally you're only interested in a specific band where the transmissions you're interested in lie. It is unreasonable to expect one receiver to cover audio to microwave frequencies.

Brian