I'm testing the "5 Level Twister HHO Electrode" device.
It works fine!

For the moment,  I'm not able to measure the gaz volume produced. Before that, I have to build the 'container'  and to figure out how to fix the electrode. I have all the stuff notably one transparent acrylic tube.

What I have done is:

1) Testing the device with tap water (*not* distiled water).
I could see some amazing  'Alka-Selzer' effect (the bubbling are 'huge' and  not  'stuck' but free to move 'up'). My amp consumption was about 4 amps. I had already tested a stainless steel  parallel plates bl' gizmo and could not see this behavior. The bubbling were not so 'huge' an desperatly 'glued' on the plates.

2) Testing the device with tap water and "bakin soda" as electrolyte.
I guess I was too generous as I could not see anything but a  very fuzzy seething  mess :)). My amp consumption was about 16 amps (too much, IMHO).

3) Testing the device with tap water and less  "bakin soda" as electrolyte.
Here we are: a real "DallasGB's Alka-Selzer Effect"  (TM)! (With a mere 12 V bat)
Amps consumption: about 6/7  amps. I'm looking forward to being able to measure le volume of gaz produced.

4) Testing the device with the same  mixture but with the Dave Lawton circuit (V1):
 
 

I could also got very  interesting results. My amp consumption  was between 2 amps and 5 amps (depending on the freq). Actually this circuit is too complicated for figuring out anything. Too many potentiometers!!!
 
 

Actually, the amp comsumption (and the gaz volume, BTW - (as far as I only  can see it for the moment ))  - is not depending on the frequence but only  depending on the duty cycle. It sounds like this device were  preferering DC current! Of course, it  works with square pulses but only with a huge duty clycle (97% or more). Now, a 98% duty clycle is not far from a DC current. Is it? In fact, I was puzzled by all these 'Lawton circuits' which are, IMHO,  misleading. = when you think that you  are tuning the frequency you are also 'tuning'  (changing) the duty cycle and reciprocally! I have now tried a lot of frequencies and I could not  'see' (I'm not still measuring the gaz volume)  any obvious change/improvement.

Projected  experiments:
a) Trying to find out the optimum frequency with a more simple circuit. For example:

b) Using the Lawton's Circuits V2 and V3 that are claimed to be more efficient. .

Click on the images to get them full scaled.

c) ASAP:  building the container to be able to get an accurate gaz volume production measurement.
 
 

ASAP does not  imply any precise agenda to me.. :)) I ordered (in France), a 'couple' of weeks ago,  a 50mm diameter acrylic tube to build a 'bubbler'. I'm still waiting. Stuff from the USA are coming faster!!! Anyway, some pictures of the devices (also) waiting for assembly.....:))

d) Making some pictures and even a vid.
 

What I also have tested:

Pluging my Peter Davey Heater(s) on a 12V bat.
It also worked!  Amazing!
I got a lot of non 'gluing'  (= free)  bubbles (but far less than with the 'DGB' device).

Pluging my Peter Davey Heaters on this Version One (V1)  Dave Lawton circuit:
It did not work!
Why? My guess is because the cups are too dense/thick  to be able to vibrate at the Dave Lawton circuit  frequency.
Please notice that this device is intended to be plugged on the power grid (220 vols/60 Hz  in France or 110 volts/50 Hz  in the US).