Making a Blend Machine

I have made a fairly decent galvanic machine using professional stylus holders and needles. It incorporates a meter and a footswitch as well as a programmable timer.

Being a professional electronics engineer with experience in designing complex devices including microprocessor driven systems, I’d like to add thermolysis to my design. Can anybody point me in the direction of a book or website that will have some info on the RF signal to be injected into the follicle? Basically I need to know frequency, peak-to-peak voltage, treatment timings and the relative start/finish times of RF signal delivery compared to the start and finish of the galvanic current.

As I cannot find any books on the subject on the shelves of book sellers here, I need to know the book(s) with the right information to order on the web.

Here are some very rough ideas:

You probably have already done this, but for the DC, you’re going to want a constant current, not constant voltage or constant resistance supply.

For the RF, voltages run up to 100V. I suspect that’s RMS but don’t know. To avoid electrocution, you must not have the RF connected to the DC ground.

You’ll want a DC current meter and control and a RF voltage meter and control. Analog meters are better as they’re easier to read quickly - and the key factor is not precision (as with digital meters) but quickly assessing whether the currents are flowing and the voltage is present.

Ideally, the RF starts warming the follicle, and then the DC starts and ramps over about 1/10 the total treatment time.

I don’t know what frequency the RF is.

For face treatment, you’ll want to keep the RF on at a constant level. For body (fast blend) treatment, pulsed RF is advocated.

Two-handed practitioners test the hair while treating it. Hence they don’t need timers; they just hold the foot pedal down until the hair releases. They also advocate doing an after-treatment of two seconds of DC alone.

I don’t know of any resource that describes the design or characteristics of a pro system. The companies don’t talk about it, preferring the machine designs to remain mysterious.

Hope that helps. I have to say, though, I think you’d be better off buying a used pro machine than trying to build it yourself. Of course it’s fun to design and build it, but unless you’re really sure you’ve got the desired machine characterized, there’s a good chance you’ll miss some aspects you’re looking for. I would make a completely manual (rather, completely pedal!) machine, with no timers or other automated apparatus.

[ July 12, 2004, 12:08 PM: Message edited by: DIY’er ]

I have also been thinking about how to build such a machine. I was able to determine that the frequency used is 13.56 MHz (FCC assigned).

The RF voltage range spec for some machines on the market ranges between 30-120 or 90-140 VRMS.

Typical treatment for “fast” thermolysis is about 3 pulses of 150ms for a total treatment time between 400-600 ms. I also found a reference to “slow” thermolysis using 10-40 VRMS over a 5-20 second total treatment time.

These are all just anticdotal powers and times I found by looking up machine specs and individual treatment testimonials. I would certainly seek out a definative source for this information experimenting with this on my own face!

By the way, did your galvanic machine use a constant current circuit? If so, do you have any references to the circuit you used?

Please keep us posted on your progress.