Micro-current electrical stimulation device

Discussion in 'The Completed Projects Collection' started by wayneh, Aug 15, 2016.

  1. wayneh

    Thread Starter Expert

    Sep 9, 2010
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    Are you sure you want ~40Hz? My device is more like 0.5Hz. If I recall correctly, a TENS machine can hit 40Hz. You can get a pretty nice one for ~$30. It does NOT supply a micro current though, and uses voltages over 100V. Definitely not for tongue use.

    My circuit should work fine at 40Hz, and limit the current to 600µA or less, but you'll need different timing components on the 555 (or 556). If you want to set the current limit higher, that shouldn't be hard either but it would be a good idea to work it out in simulation to be sure. A 9V battery across a human head my not be able to drive more than a few mA anyway.
     
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  2. jcdolce

    New Member

    Feb 28, 2017
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    thanks for publishing this wayneh--nice work! interesting idea of using the 4017 the generate a reversing waveform. this is similar in function to several of my microcurrent devices including the acuscope. I can vary the frequency between a range of 0.5 - 380 hz which seems to make them useful to concentrate to local areas with the higher freqs or spread through the body with the lower freqs. what was the mod that you mentioned to do this? -regards
     
  3. mtbhomer

    New Member

    Jul 17, 2017
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    Thanks for posting this wayneh, it looks very interesting!

    I'm trying to reproduce this build, but I run into some problems of getting the circuit to work. I'm confused by how to connect the dual gang pot which is connected to the 3K R10 and R11. The pot has 3 connections (1, 2 & 3). In your drawing 2 and 3 are bridged together, but there is no further connection from point 1. I suppose it should be connected to GND, is that correct? (I tried to connect to GND, but this still doesn't work unfortunately).
     
  4. wayneh

    Thread Starter Expert

    Sep 9, 2010
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    Right, the opposite pole is grounded. That’s show in one of the drawings but was omitted from the one that’s confusing you. The wiper is connected to the end opposite to ground to limit the impact of the wiper temporarily skipping off the resistive material as it moves. The pot goes th max ohms instead of infinite ohms.

    Sorry it’s not working. How are you testing it?
     
  5. mtbhomer

    New Member

    Jul 17, 2017
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    Thanks for the reply.

    It's probably due to my incompetence with analog electronics. As a first step, I double-checked all traces and connections in the circuit for shortcircuits and proper connections. Now I'm using a scope to see if there is a waveform visible in any part of the circuit. However, it seems all the outputs are stable, no waves generated. To be honest, I'm not very certain how to start with properly debugging it.
     
  6. wayneh

    Thread Starter Expert

    Sep 9, 2010
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    Divide and conquer. Check that you have power at each IC. Check the input and output voltages. You might want to break the connections between ICs to isolate the various stages. Make sure the timers are working and move forward from there.
     
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