Peter Davey Heater

[devrimogun]

Sandy is there a way to make use of that 1.2?

[Sprocket]

Attempting to take this up a level, so I sampled my inner bell's sound, found the fundamental frequency was pretty close to 1000Hz (933Hz), so ground it down till I got closer.  As you can see, not an ideal bell by any means, and hitting the magic 1000 proved illusive!  But I did look for effects between 990 -> 1010Hz with no success.  There's also a little soundfile attached - the bells sounds first, then a 1000Hz tone I generated for comparison.  As you can hear, (and see in pic.) they are pretty close.

So, question, am I right in thinking that 1000Hz is a harmonic of the 50Hz mains frequency?

[forest]

The question is not if your bell resonate at 1000hz ,rather if a simple connection to AC is capable of force bell vibrations at all. I don't see it happens.

Is there a possible to build a spark gap for 220 - 400V ? How small should be  gap ? I'll try to build a circuit with 400V capacitor and spark gap as in patent mentioned by me.

[Sprocket]

Well, the idea that the bell resonates at a harmonic of the mains frequency is the prevaling notion as to how the Davey heater might work, so if true, of course it matters that the bell resonates at a harmonic of the fundamental - in this case 1000Hz - as maximium power transfer will occur at a harmonic frequency...

[nul-points]

Sandy is there a way to make use of that 1.2?

hi Dev

at the moment the experiment is a single pass: switch charge the output cap thro' a load & then discharge it thro same load - end of run - measure results

the next phase for me (and possibly for at least one other member) is to automate that process repetitively and confirm if it still delivers 1.2 under the new conditions - the output will then be a cap charge/discharge AC waveform, approx 2.7V pk-pk through a resistive load, for an 8V input, with a half-cycle of some tens of seconds

not a very useful output yet - still only an OU heater at this level!

however the new automation process will open the way to checking for OU & additional resonance at different operating frequencies, and possible transformer coupling etc

getting the output volts up by a factor of 3+ would mean we could go for self-sustaining attempts but that isn't practical at the moment

all the best
sandy