Need help with muscle stimulator project

[Armita]

hello evryone
I want to build a muscle stimulator for a school project, ( I attached the source circuits )
but i decided to change it a little, instead of a signal generator part i want to be able to connect it to an audio source ( like an mp3 player or a computer ) ,
but the output signal become very weak for frequencies under 1000hz and very strong for freqs over 2k,3khz.
tens unit frequencies ranges between 20 to 500hz, i don't understand what the problem is, any idea what should i change/add to make it work for 100 to 1000hz maybe .
thanks

 

[duke37]

2300Hz is 2.3kHz or 2k3Hz.
It is Hz not hz, Herr Hertz prefers a capital for his name.

If it does not work well at lower frequencies then I would suspect that you do not have sufficient inductance.

Xl = 2*pi*f*L

 

[Armita]

sorry for the typo, gonna try with different inductor ,any suggestion on that ?
thanks.

 

[duke37]

You could try a 12V mains transformer used the 'wrong way round'.

 

[AnalogKid]

Patient-contact electronics are *v*e*r*y* dangerous.

What output voltage are you trying to produce, and why? What research have you done into TENS waveforms, pad resistance, skin resistance, and ***current limiting***?

Also, what is the value of the inductor in the first schematic, and what is its core material?

AND, what are the safety ratings of the power supply for this project?

ak

 

[CDRIVE]

hello evryone
I want to build a muscle stimulator for a school project,......

I don't think your instructor, school, test subject or the school's 'Risk Management' department is going to like your project.

Chris

 

[davenn]

Patient-contact electronics are *v*e*r*y* dangerous.

I don't think your instructor, school, test subject or the school's 'Risk Management' department is going to like your project.

agreed with both
and we don't allow these sorts of discussion here because of the dangers

@duke37, @AnalogKid, @CDRIVE
In future, don't respond to posts like this ... just report them so they can be dealt with quickly

cheers
Dave


thread closed