Plasmatweeter

[Marco audio]

For the moment à 3,9ohm or a coil at the entrance of the rf circuit doesn't change anything.However the tube seems colder.

 

[Moderation Team]

The Moderation Team would like to point out to those following this thread that the circuit shown in post #341 is potentially lethal as shown.

The commercial variant in post #343 does not suffer these issues, furthermore the addio input is isolated via a suitably rated input transformer.

 

[Marco audio]

Modération team: please delete the message or picture.

 

[Marco audio]

The Moderation Team would like to point out to those following this thread that the circuit shown in post #341 is potentially lethal as shown.

The commercial variant in post #343 does not suffer these issues, furthermore the addio input is isolated via a suitably rated input transformer.

Please delete him.

 

[Lampie519]

Maybe you coils need to be tuned better as well. You also can try a higher value grid resistor. 50k or so.

 

[Lampie519]

Please use an isolation transformer always! It is not an advise but is a must to keep you alive!

 

[Lampie519]

Hello Marco, maybe the screen voltage is just too low. Because your circuit oscillates already with help if a screw driver.

 

[Lampie519]

You need to build an audio driver anyway so make it adjustable.

 

[wintermute]

Hi Marco, the circuit has been the subject of much discussion and it would be disruptive to remove it now. The post in quetion has been edited to give a warning. Please heed Lampiee519's advice. Sometimes it is better for these things to remain so people can learn how NOT to do things.

 

[Marco audio]

Ok Lampie thanks for your reply.
Hello Hiver. I understand.
But today there is no more schems In this topic.

 

[Marco audio]

Hello ,
I dont' know how to tune my coils.
Do you know where can i have some explanations, please ?
I tried 5 différent starter coils.
15uh;13,5 uh;27uh,10uh and more than 27uh but no succes.
Oscillator coil is 10uh.
I tried without the 3,3nf capacitor In front of my RF coil;it works worse.This capacitor brings an amélioration.

 

[Marco audio]

Hello.

Finally the first self-sustaining flame.
I removed my variable capacitor and built a loop with copper wire.
Conclusion: a variable capacitor is not enough.
In my opinion, the loop and the tip constitute electrodes.

 

[Marco audio]

3 loops were tested at différent level from the spike
The best is a near 3/4 circle diamètre around 50mm at the middle height of the spike.At the top flame is strong but became noisy (50hz).
At the base ,flame became weaky.

 

[Lampie519]

That is good news!

 

[Marco audio]

Look at the voltage

 

[Lampie519]

650V almost. Just watch out for your tube. Check the current and if it within range it should be fine.

 

[Marco audio]

I will check it as soon as possible.
I'm now learning about transmitter to understand the ionovake schematic and improve my device.
I want to know how i should design my coils :
Resonance coil is OK for me, but RF choke coil is mystérious. I just builded à 90uh one(mesured,65 mm long with enameled 0,8mm copper wire on a toilet's papper roll) and tested it:
It works not so good:the flamme is weaker as with the 15uh one at first.
Most of schematic have a 100uh at the entrance of the circuit,why ?

 

[Lampie519]

A choke is to remove unwanted signals. So you do not really need to change these values as they need not to resonate.

 

[Marco audio]

Not only a choke ,look at the picture.
And @ 35mhz a 90uh coil gives 20k.
If the Anode current is 100ma,the voltage drop is 2000v.
How much is your 519 tube current ? I think it is 150ma.If your plasma speakers run at 27mhz with a 100mh RF choke, how much is the voltage drop ?
I think it's more than the voltage power supply.
But it works, and i wonder how...

 

[Marco audio]

Hello,
Strong and silent flamme with ceramic capacitor adding.
Modulation is OK ,i use for the moment a 10w 220-9 volt ferrite transformer.

Happy winter fest