radio wave generation for medical instruments

[selva murugesan]

hello

i dont know , how to create the high frequency (40Mhz) RF wave with 10 wattage power . could any one please give some idea about this?
or some suggestion.

 

[audiomik]

can you provide more information for this please; the impedance which you want to generate your 10 Watts into is important for a start

Mik

 

[kripacharya]

hello

i dont know , how to create the high frequency (40Mhz) RF wave with 10 wattage power . could any one please give some idea about this?
or some suggestion.

First you design/ make an oscillator of low power and stable frequency of 40MHz.
Add a buffer stage.
Now design/ build a pre-driver to amplify the signal.
And finally add one or two power amplifier stages to result in 10watts.
Since usually this drives a 50ohm load, then for 10w you need a power rail of around 12volts at least.

 

[Bob60]

That is a problem, because body like a load is not stable and for solid state PAs should be protection with 10-100W power. In any case it`s not so trivial task like it looks from firs view. Typically and approved solution is generation up 100W with tube + antenna like part of oscillator, or with antenna tuner if you have PA stages and excitator separately. If you move to @ GHz and pow up to 30dBm, it looks much easier.
And you should define, what you want? Inside heating hi pow and low freq, or some therapeutic effects with some special points and low power.

 

[E Kafeman]

Medical - Power RF - DIY -> Do not know how? Sounds like a dangerous combination.
Doing something like this require basic RF knowledge both theoretical and that you is familiar with instruments to measure and verify if you have designed a 40 MHz/10 Watt amplifier and not a self-oscillating harmonic generator. Even a smaller design mistake and a such PA can easily disturb or even block airplane communication at 120 MHz for a wide range.
Theoretical skill is no enough, I would never build something like this without good measurement tools, and a lot of experience and understanding from RF things such as simple filters, small oscillators and RF layout requirements.
Medical is also a bit unspecified. Should the PA be designed according to personal RF safety regulations, extra electric shock isolation och is it something related to RF signal quality? Guess your local radio regulations must still be met even if you is using a license-free ISM band for a "medical equipment".