How do I generate microwaves?

[Isak Sebastian Lytting]

I need to build a small device to transmit microwaves into a
bulb of gas, but I don't want to use a microwave-oven. What kind
of device is used to transmit microwaves?

--
Isak Lytting
ilyt...@datashopper.dk
2:238/197.13

[Trash]

How much power and at what frequency ?

You could try rubbing two non-linear devices together like LED's
while they are producing light. You can then mix the light and the
heat togther to produce microwaves. ???

- trash

[Robert Macy]

ISL>From: ilyt...@datashopper.dk (Isak Sebastian Lytting)

ISL>I need to build a small device to transmit microwaves into a
ISL>bulb of gas, but I don't want to use a microwave-oven. What kind
ISL>of device is used to transmit microwaves?

You can buy a relatively inexpensive source of microwaves. The security
industry uses them (around 10GHz) for motion detectors. The name of the
main supplier escapes me right now.

But if you're trying to ionize the gas; you won't get enough power from
that kind of source.

There was a company in Santa Clara, CA called Diablo Systems that
developed microwave excitation of gases to make extremely efficient
light sources. The whole product fit into a standard lightbulb envelope
and could replace all your light bulbs.

Alas, never became a product to my knowledge.

- Robert -

* OLX 2.1 TD * In a Dog Eat Dog World you have to expect to eat some dog

[Sam Goldwasser]

In article <95112909...@engineers.com> rober...@engineers.com (Robert Macy) writes:

<snip>

> There was a company in Santa Clara, CA called Diablo Systems that
> developed microwave excitation of gases to make extremely efficient
> light sources. The whole product fit into a standard lightbulb envelope
> and could replace all your light bulbs.

> Alas, never became a product to my knowledge.

They may be called E-Systems or something like that. I believe it was
RF but not microwaves. You can understand the problems in getting such
technology approved in modern society.

--- sam

[Dan Mills]

In article <SAM.95No...@colossus.stdavids.picker.com>
s...@colossus.stdavids.picker.com "Sam Goldwasser" writes:

I think that Philips developed a system using a RF source and a globe of
low pressure gas. It had a very long life and was efficient. EMC was not a
problem. Cannot remember the name at the moment.

--
************************************************************
* And on the first day the lord said... * *
* LX1, GO! and there was light. * Dan Mills. *
************************************************************

[THOMAS STICHELBOUT]

god Dag,

You should precise at which frequency you want to generate your wave.
For a few GigaHertz you can still produce microwaves with As-Ga transistors,
otherwise after 15 GHzt, you would be obliged to use Klistron, Magnetron or
others special device.

Try also to get books about Microwave theory to better understand the problem
involved. (Microwave and Hyperfrequencies, implies a lot of knowledge to cope
with)

[Andy Borsa]

In article <49hai8$s...@srv5.esiee.fr>, stic...@esiee.fr says...

>
>You should precise at which frequency you want to generate your wave.
>For a few GigaHertz you can still produce microwaves with As-Ga transistors,

As-Ga? Is that an Arsenide-Gallium field effect transistor? Must be the
soul-mate of the GaAs (Gallium-Arsenide) FET.

--
Andy Borsa -- !!!The Universe is discretely analog!!!

[Kevin McMurtrie]

In article <95112909...@engineers.com>, rober...@engineers.com
(Robert Macy) wrote:

>ISL>From: ilyt...@datashopper.dk (Isak Sebastian Lytting)
>
>ISL>I need to build a small device to transmit microwaves into a
>ISL>bulb of gas, but I don't want to use a microwave-oven. What kind
>ISL>of device is used to transmit microwaves?
>
>You can buy a relatively inexpensive source of microwaves. The security
>industry uses them (around 10GHz) for motion detectors. The name of the
>main supplier escapes me right now.
>
>But if you're trying to ionize the gas; you won't get enough power from
>that kind of source.
>

>There was a company in Santa Clara, CA called Diablo Systems that
>developed microwave excitation of gases to make extremely efficient
>light sources. The whole product fit into a standard lightbulb envelope
>and could replace all your light bulbs.
>
>Alas, never became a product to my knowledge.
>

> - Robert -
>
> * OLX 2.1 TD * In a Dog Eat Dog World you have to expect to eat some dog

I don't think the bulbs were as high as microwave. The obvious reason
that they had no product is that 60W of RF energy is dangerous to home
electronics and can cause burns.

[Richard Ranson]

In article <95112909...@engineers.com>, rober...@engineers.com (Robert Macy) says:
>
>
>ISL>From: ilyt...@datashopper.dk (Isak Sebastian Lytting)
>
>ISL>I need to build a small device to transmit microwaves into a
>ISL>bulb of gas, but I don't want to use a microwave-oven. What kind
>ISL>of device is used to transmit microwaves?
>
>You can buy a relatively inexpensive source of microwaves. The security
>industry uses them (around 10GHz) for motion detectors. The name of the
>main supplier escapes me right now.
>

The simplest way to generate a small amount of microwave power is a Gunn
diode. You apply a few volts DC and get RF energy out. The frequency
depends on the length of the diode so you needed to get a particular
device for a particular frequency and the efficiencies are generally
quite poor. ( i.e. 5% ). The maximum power you can get from common
or garden Gunn diode is about +20 dBm ( 0.1 Watts ).

For the next level of power look for a Klystron, which is a vacuum tube
device, they are sometimes available on the surplus market. You can get
many Watts from a Klystron but you will need heater and HT supplies.
The heart of a microwave oven is a device called a magnatron, which is
another vacuum tube type of device which can generate up to killowatts
of power.

As for suppliers and circuit ideas try looking in some amateur radio
magazines and books. They have a 10 GHz band and are usually very
inventive and cost sensitive.

Richard