HF Circuit 100 v 50-100 megahertz.

[Trauts22]

That's me.

Quote: "Experience is directly proportional to the value of the equipment ruined". That's me too.

 

[schmitt trigger]

The only thing that I can add to this thread, is that one cannot have more power at the output than at the input. It would break several physical laws.

The corollary to that is, that anything -and I mean anything- you put in between your source and your load will have losses. Losses which will be subtracted from the input power to comprise the actual power available to the load.
With that in mind, the best way to improve your efficiency, is to use a plain wire, with the largest gauge you can muster, to feed your lamps directly from your AC mains.

 

[moty22]

Hi Trauts22.
First I'm disappointed with some of the comments from the experts, I respect their opinion and knowledge though.
Nobody corrected you about the frequency. Induction heaters for hobs use 50-100 KHz and not MHz, they should have picked that up when you described the coil.
All of them forgot that halogen lamps have light efficiency of 4% (the other 96% is heat) it means that if you make 100% efficient lamp then the light will be 25 times stronger for the same power and the bulb will be cold.
It is very possible that the lamps you have increase efficiency at RF frequencies.
I worked for 15 years developing the first solid state induction heaters using mosfets, we also produced plastic welding machines using up to 50KW of 27MHz RF.
If you put a florescent tube in RF field it illuminates with no voltage connected to it. It is possible that your halogen lamps are filled with xenon or another gas that increases the efficiency in high frequency.

You can use your hob as a generator. The best way to measure the voltage is using a fast switching diode and 10K resistor to a 0.1uF cap. Measure the DC across the cap with a voltmeter and you will get reasonable idea where you are.
The difference in currents between the hob running with or without the bulbs will give you an idea how much power goes to the bulbs.

 

[blueroomelectronics]

Hi Trauts22.
First I'm appalled at some of the comments from the experts, I respect their opinion and knowledge though.
Nobody corrected you about the frequency. Induction heaters for hobs use 50-100 KHz and not MHz, they should have picked that up when you described the coil.

How do you correct fairy tale devices, it's like debating unicorns. I've seen some overunity knobs claim GHz frequencies.

 

[schmitt trigger]

Having worked as an architectural consultant for lighting matters, the important parameter to measure is lumen output vs. watts input.

Measuring lumens is involved, require that one integrates the total luminous flux over a spherical surface.
But you can get away by measuring luxes, if you make an A/B comparison of your light source fixed in position with respect to an inexpensive luxometer, and compare the luxes fed directly from the AC mains and then, maintaining the IDENTICAL SETUP, perform the measurement with the circuitry you describe.

 

[moty22]

How do you correct fairy tale devices, it's like debating unicorns. I've seen some overunity knobs claim GHz frequencies.

My name and Trauts22's name end with 22 it's because we both belong to a secret religion that believe in unicorns.
I meant to say that it is ok to give an opinion about the idea but Trauts22 asked for advice where to get a generator and he didn't get the advice.
I'm inclined to agree with your opinion but I think that if Trauts22 will have the guide to do the experiment he will learn more about electronics and about unicorns.

 

[Tony Stewart]

Halogen gas & tungsten filament works because the high temp not whether it is AC or DC
Thick quartz glass is used that withstands higher gas pressure AND that prevents filament burn-off at the higher temps.

The Halogen regenerative cycle works above 250'C gas temp envelope for filament temps hotter than ordinary tungsten bulbs but the cycle deposit unevenly to the cooler spots, so that doesn't improve lifetime, but it might be possible to make a long MTBF bulb in a more expensive larger quartz tube.

As neither AC nor DC affects the thermal cycle, there is no benefit from using AC.
RF would not improve conduction losses and would probably be less efficient.
RF does not assist with the thermal cycle at elevated temperatures nor the conduction losses of tungsten.


Plasma bulbs from Philips on the other hand, make great EMI generators and the arc resonates with great havoc to cell-phones and other RF devices and require expensive PSU and Faraday Cages for commerical use. They run at even hotter flame temperatures but give closer to sunlight performance.

 

[Tony Stewart]

here are some DIY plasma lamp power supplies, but do use a microwave like light/ RF shield.
I should warn you, RF power in hundred watts with hundred MHz range is Caterogenic, meaning, causes bloodshot eyes then cataracts after prolong use.

Even a Tx into a dummy load without a lid to the lossy coils will cause bloodshot eyes after a day. ( just ask Jack Askew on web).... hehe Although I haven't seen him for 35 yrs he used to get this at work.

 

[moty22]

here are some DIY plasma lamp power supplies, but do use a microwave like light/ RF shield.
I should warn you, RF power in hundred watts with hundred MHz range is Caterogenic, meaning, causes bloodshot eyes then cataracts after prolong use.

Even a Tx into a dummy load without a lid to the lossy coils will cause bloodshot eyes after a day. ( just ask Jack Askew on web).... hehe Although I haven't seen him for 35 yrs he used to get this at work.

Hi Tony.
Interesting information.
If the induction hob is used do you know of similar danger? The frequency of the hob is likely to be 35KHz and not more than 100KHz.
The original idea try to prove that you can get better efficiency. It's based on comparing measurement of power only, they ignore the fact that light output and efficiency of halogen lamps isn't linear with power or temperature of the filament. If you power a bulb with higher voltage the efficiency rises but the life decreases.

 

[Tony Stewart]

Hi Tony.
Interesting information.
If the induction hob is used do you know of similar danger? The frequency of the hob is likely to be 35KHz and not more than 100KHz.
The original idea try to prove that you can get better efficiency. It's based on comparing measurement of power only, they ignore the fact that light output and efficiency of halogen lamps isn't linear with power or temperature of the filament. If you power a bulb with higher voltage the efficiency rises but the life decreases.

100kHz no problem but better for Eddy Current losses and heating of Aluminum Pots unlike 35kHz which renders them useless. Eyes damage respond to heat absorption which increases towards GHz microwave. not kHz. Basically sensitivity increases with freq. So 1 GW at 60Hz is harmless at a safe distance but 60W at 1 GHz is harmful near eyes. SAR computations factor f.