Re: 150Khz Antenna question

Jacques St-Pierre wrote:
> "Jacques St-Pierre" <multelec@[EMAIL PROTECTED]
> wrote in message 
> news:7hMak.1311$1o6.1143@[EMAIL PROTECTED]
> 
>>Anyone can help me with the design of a compact 150Khz antenna?
>>
>>Let me explain the goal, I need a way to induce a 150Khz signal to a 
>>compound for an experiment.
>>
>>I will build a supply using a LM555 at 13.8Vdc and a transformer to 
>>produce a 150Khz square wave of 140Vp-p approx.
>>
>>I need to couple that 150Khz signal to a sort of compact antenna to 
>>emit/induce the wave to the compound. The coil should be compact enough
to 
>>be insert in a plastic case of 2" x 4" inches.
>>
>>What is the best length of wire to use? What is the best way to wound
it?
>>
>>Any suggestions?
>>
>>Jacques
> 
> 
> I am sorry I can not give much detail, but my customer did not wish to 
> disclose much information and he also did not give me much to work on.
> 
> Since you all offer help, here what I have and can give you as
information:
> 
> The unit should work on a 13.8Vdc power source.
> It must be package in a small non corrosive box around 4" x 2" x 1".
> It should emit an electric field from a 100 to 150 Vp.p. signal.
> Frequency must range from 150Khz to 200Khz.
> Antenna or anything similar should be enclose in the box.
> It mush have a low power drain.
> It must be low cost.
> It will be attach to a circular fluid pipe of 1/4" to 1/2" going strait
in 
> parallel with the box.
> The fluid has a low electric conductivity and density lower than water.
> 
> Now from what you said, I can add this:
> 
> It will probably use a capacitive coupling.
> It may have to be enclose in a metal box to prevent parasitic emission.
> It may require a flat  fluid pipe for maximum coupling.
> It will require a sine wave to drive the output transformer or use the 
> antenna as part of the oscillator.
> 
> Hope this help.
> 
> Bye
> Jacques
> 
> 
   Be careful concerning small fluid pipes, especially flat ones.
   Fluids tend to "stick" on the walls and thus create turburlent flow 
meaning a higher than expected resistance and lower than exected flow
rate.