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HF Circuit 100 v 50-100 megahertz.

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Trauts22

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I want to build a circuit with 240 volt 60 cycles input, 100 volt 50-100 megahertz output. The extent of my knowledge is best summed up by watts = volt x amps. Can anyone help?
 
We also need to know what the load is. What are you driving?
This could be a BIG fm-transmitter?
 
Sorry for the delay. I'm doing some experiments with halogen bulbs and wondering if they will be more efficient at much higher than mains frequency. I've just been to my local college to get some measurements because I don't have much more than a multimeter and ammeter.
If you are familiar with the gegene setup (**broken link removed**), I am using an induction hob to drive a flat coil, which in turn drives a bank of six 400 watt halogen bulbs. I have a consumption meter on the 240 volt mains side and thought I could use another one on the coil output to compare the loads, but the puff of smoke and blank screen told me otherwise. When the hob is consuming about 1.7 kilowatts, all the lamps are burning brightly. The coil barely gets warm, so I would estimate it is carrying 3 amps max. The halogen bulbs are mounted between two rails and I can touch both at once with just a slight tingle, so I would estimate the average voltage is not more than 100 - should be roughly 300 watts.
I got the college to do some measurements with an oscilloscope. They show a basic 60 hertz frequency, but with lots of harmonics and a peak voltage of about 400. The coil is a flat pancake single wound with 50 turns of speaker wire and there are six 400 watt bulbs.
It was the harmonics that interested me and I wondered if I could get similar performance from a high frequency circuit and get rid of the induction hob.
Hope this all makes sense.
 
megaHz = millions of Hz.


I doubt that a halogen lamp cares if the frequency is >50Hz because the thermal mass of the filament cannot respond beyond that. Note that at 50Hz, the power pulses to the filament are happening 100 times per second.
 
All can tell you is that you will get better lifetime running them on DC and better vibration performance using lower voltage bulbs and the intensity variations can been seen at 60 Hz with a suitable detector.

I used plenty of ELH lamps operating at 120 VDC 8 hours a day. and EYC 12 V lamps where vibration and better stability were a factor. The EYC's were used as a DC bias on laser scan of a photo-detector. We also operated some on 120 VAC with bulb backup for lifetime testing of our detectors. These may have operated 24/7 for say 6 months.
 
As I figured, don't belive anything you read on that free energy site.
Not a question of belief, I want to get an understanding of what is happening. I have a circuit with around 100 volts and 3 amps driving 6 x 400 watt halogens so bright, you can't look at them. In order to investigate, I want to build a 100 volt variable high frequency circuit. Can anybody help?
 
Not a question of belief, I want to get an understanding of what is happening. I have a circuit with around 100 volts and 3 amps driving 6 x 400 watt halogens so bright, you can't look at them. In order to investigate, I want to build a 100 volt variable high frequency circuit. Can anybody help?

The fellow in the videos has some nice gear but no knowledge of how to properly use it or what he's actually measuring. Go back to the college and sign up for a basic electronics course if you want to understand what's happening and get a grip on how electricity works.
 
My " Licence " post was made rather tongue in cheek ... How you going to screen a lamp ? sort of defeats the object ?
 
My " Licence " post was made rather tongue in cheek ... How you going to screen a lamp ? sort of defeats the object ?
I'm not looking at the lamp as a source of light, just interested in what is going on in the circuit. Trying to understand how 6 x 400 watt halogen bulbs can be so brightly lit by a circuit consisting of wires that would carry around 3 amps at a voltage that is safe for me to touch the terminals, which I would estimate as 100 volts max. My absolutely basic knowledge tells me that must be in the order of 300 watts and the bulbs are 2,400 watts. The only thing I could think of was that the HF harmonics that show up on the scope could be playing a part, so I want to feed a circuit with a controlled high frequency in an attempt to find out.
I wondered if this would do the job? **broken link removed**
 
Your entire premise is faulty, if the bulbs are lighting brightly it's because you're feeding high power to them - frequency is totally irrelevant, and DC would probably be best.
 
The extent of my knowledge is best summed up by watts = volt x amps.
With that statement in mind, I will say this:

Generating 100 volts at radio frequencies is quite easy especially if you use older thermionic valve (tube) technology.

Measuring that 100 volts at (say) 100MHz can be a bit problematic. Due to standing waves, you could have 100 volts at one point on a pair of wires and 0.75 metres away on the same pair of wires you could have 0 volts.

To do experiments with that 100 volts at 100 MHz, you will need a screened room unless you want to jam every FM broadcast radio station in town.

Generating 100 volts at 100 MHz with several hundred watts of power so that you can drive your halogen lamps, is not an easy task, especially for someone with very limited knowledge of RF electronics.
It will also get very expensive, very quickly.

All in all, I think that your idea is a bit of a non-starter.

As for the measurement which you have made with the coil on the induction heater, consider that your meter will probably (almost certainly) not respond correctly to the "harmonics" which were displayed on the oscilloscope. The meter display will be wrong, which is why you appear to be getting power from nowhere.

JimB
 
The meter display will be wrong, which is why you appear to be getting power from nowhere.
JimB

Forgetting the meters and measurements for the moment, from my very simple viewpoint I have 2400 watts of halogen bulbs burning very brightly on a circuit with speaker wire that can probably carry 3 amps and I can safely touch both terminals on the lamps, so I would estimate not more than 100 volts. I appear to have around 300 watts going in and 2400 coming out. I'm interested to know what is happening. Have you any ideas?
I'm trying to remove the induction hob from consideration and looking at what is happening in the circuit containing the coil and bulbs. trying to see if there is another way to produce the effect without the induction hob and possibly the coil.
 
All learning here ! Think the brightness is because the chemical properties involved ... ( save you searching )

A halogen lamp, also known as a tungsten halogen, quartz-halogen or quartz iodine lamp, is an incandescent lamp that has a small amount of a halogen such as iodine or bromine added. The combination of the halogen gas and the tungstenfilament produces a halogen cycle chemical reaction which redeposits evaporated tungsten back onto the filament, increasing its life and maintaining the clarity of the envelope. Because of this, a halogen lamp can be operated at a higher temperature than a standard gas-filled lamp of similar power and operating life, producing light of a higher luminous efficacy and color temperature. The small size of halogen lamps permits their use in compact optical systems for projectors and illumination.

You growing Cannabis ?
 
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