Thanks for the explanation, really cleared some things up for me. Out of curiosity what model/voltage rating of bypass caps did you use, are they also the soviet K15Y-1 series?
Nice setup! Just one remark regarding the grounding: The MOT has a parasitic capacitance between primary and secondary that conducts quite a lot of the RF into mains anyhow. I think it´s better if it´s connected to PE than if it´s going into L and N. In the best case you connect your setup to mains by a common mode choke. It´d even help to wind the mains cable 5-10 times through a big ferrite torus, this already blocks quite a lot of the RF.
Great video and explanation. There seems to be additional coil (4:17) between filament transformer and tube's filament that is not in the schematic. Is this essential?
Hey, The additional coil on the filament transformer is to drop the voltage a bit. My filament transformer puts out 2v too much under load. That inductor fixes that.
another really interesting video. The only question i have is why the bypass cap must be rated for 100pF? What is the reason that it must be that value? And why must there be 5 mot caps? can it be lower or higher and what changes should you make when you change the amount of mot caps?
The cap doesn't have to be 100pF. The cap still needs to be carefuly chosen becouse it will effect the grid drive. Most of the time 100pF is perfect. Only with big tubes like gu39b gu23b gu66a etc you probably need more. About the MOT caps I chose by instinct. But they are critical. More caps will help to maintain a higher voltage at an given current draw. I think in this case 3 caps would also do the job. But with for example one cap the voltage would sack to much.
Sehr ordentlicher aufbau!! In deinem alter habe ich recht schlampig gearbeitet. Mein 23,5kV verteiltransformator ist heute angekommen. Ein ordentliches gerät😂 370kg
Danke, naja der Aufbau ist anfangs auch echt scheiße gewesen aber es gibt bei solchen Sachen eine Regel. Wenn man noch nicht weiß ob es funktioniert soll man es noch nicht hübsch machen. Mann kann viel einfacher an einem Testsetup arbeiten. Wenn man weiß das es funktioniert kann man es schon machen.
@@motness muss einen stepdown trafo 400v auf 170V besorgen.habe einen mit 30kVA gefunden. Der trafo hat halt leider eine etwas doofe eingangs spannung von 167V. Ausgangsspannung ist 23525V. Vetreibe ihn aktuell mit 153V über meinen ringkerntrafo mit 2200vA
@@motness 1,5 meter dürften locker auf voller Leistung gehen. Will ihn aber nicht in resonanz versetzen, um ihn durch spannungsspitzen nicht kaputt zu machen
JavaTC or Coil Resonant Frequency Calculator (online) works well for that, but the plasma flame acts as a sort of top load, so mostly you adjust it by trial and error
Nice video. Also thanks for explaining the feedback circuit, I will probably try this with a 400W chinese triode I have:) Also how important are the dimensions and turns Ratios of the resonator, "primary" and feedback? And how did you come up with them?
Thanks, So the resonator size will set your frequency (you can adjust the frequency a bit with the turn ratio). I guessed what size of resonator I need to get 15mhz but I'm sure you can also calculate it. The ratio is very important I started with 1:1,5:2 but from there I tuned the circuit. You can just remember that the feedback should have less turns than the "primary" and "resonator" the primary should have more turns than the feedback but not more than the resonator. I tuned my feedback by just moving the connection further down that means i will have less losses in my grid resistor. If you want to tune your primary and resonator however than you can put an small metal object on your chicken stick. Than you ignite the flame and put the metal pice closer to the breakout or even touch it with the metal pice completely. If you can see that your flame gets bigger than your coil is out of tune and you bring it to tune by adding capasitance with the metal pice. If you know that you can move your Anode conetion in your coil down. That will add inductance and capasitance and your coil will be In tune.
Yes you can and I also did. But with small coils like this one it's not necessary. I plan to build an 10kva HFVTTC in that range a grounded rod would make sense.
Yes that circuit is the final version and everything is the same as in my coil. If the tube is similar you can exactly copy the schematic. Maybe you don't need the 15pF impedance matching cap but you can just test that
@@Jonodrew1286 I just looked into the datasheet of you tube. It can only do 4kv anode voltage so I would stick with one MOT like I did. Maybe two MOTs in parallel.
Nice Video and schematic! :)
Danke :)
Thanks for the explanation, really cleared some things up for me. Out of curiosity what model/voltage rating of bypass caps did you use, are they also the soviet K15Y-1 series?
Nice setup! Just one remark regarding the grounding: The MOT has a parasitic capacitance between primary and secondary that conducts quite a lot of the RF into mains anyhow. I think it´s better if it´s connected to PE than if it´s going into L and N.
In the best case you connect your setup to mains by a common mode choke. It´d even help to wind the mains cable 5-10 times through a big ferrite torus, this already blocks quite a lot of the RF.
I ended up buying rf caps and also what is the diameter of the resonators wire?
Great video and explanation. There seems to be additional coil (4:17) between filament transformer and tube's filament that is not in the schematic. Is this essential?
Hey,
The additional coil on the filament transformer is to drop the voltage a bit. My filament transformer puts out 2v too much under load. That inductor fixes that.
Very nice
Good job Bro, nice output! I'm wondering how your flame looks like when you use smooth DC instead of a doubler? Try it! :D
Thanks
I will try the smooth DC soon.
I also want to build an bigger hfvttc with my gu56 :)
Nice flame!
Thanks :)
another really interesting video. The only question i have is why the bypass cap must be rated for 100pF? What is the reason that it must be that value? And why must there be 5 mot caps? can it be lower or higher and what changes should you make when you change the amount of mot caps?
The cap doesn't have to be 100pF. The cap still needs to be carefuly chosen becouse it will effect the grid drive. Most of the time 100pF is perfect. Only with big tubes like gu39b gu23b gu66a etc you probably need more. About the MOT caps I chose by instinct. But they are critical. More caps will help to maintain a higher voltage at an given current draw. I think in this case 3 caps would also do the job. But with for example one cap the voltage would sack to much.
Sehr ordentlicher aufbau!! In deinem alter habe ich recht schlampig gearbeitet. Mein 23,5kV verteiltransformator ist heute angekommen. Ein ordentliches gerät😂 370kg
Danke, naja der Aufbau ist anfangs auch echt scheiße gewesen aber es gibt bei solchen Sachen eine Regel. Wenn man noch nicht weiß ob es funktioniert soll man es noch nicht hübsch machen. Mann kann viel einfacher an einem Testsetup arbeiten. Wenn man weiß das es funktioniert kann man es schon machen.
Deinen Trafo habe ich schon gesehen echt dick das Ding. Bin mal gespannt wie groß die lichtbögen bei voller Power werden.
@@motness muss einen stepdown trafo 400v auf 170V besorgen.habe einen mit 30kVA gefunden. Der trafo hat halt leider eine etwas doofe eingangs spannung von 167V. Ausgangsspannung ist 23525V. Vetreibe ihn aktuell mit 153V über meinen ringkerntrafo mit 2200vA
@@motness 1,5 meter dürften locker auf voller Leistung gehen. Will ihn aber nicht in resonanz versetzen, um ihn durch spannungsspitzen nicht kaputt zu machen
@G E T R E K T ich bin 15
Hello would it work as well with the same configuration but with a gu5B?
How do you calculated resonant coil? Great video!
JavaTC or Coil Resonant Frequency Calculator (online)
works well for that, but the plasma flame acts as a sort of top load, so mostly you adjust it by trial and error
Freaking beautifull 💪 I need to get me a nice tube
Nice video.
Also thanks for explaining the feedback circuit, I will probably try this with a 400W chinese triode I have:)
Also how important are the dimensions and turns Ratios of the resonator, "primary" and feedback? And how did you come up with them?
Thanks,
So the resonator size will set your frequency (you can adjust the frequency a bit with the turn ratio). I guessed what size of resonator I need to get 15mhz but I'm sure you can also calculate it. The ratio is very important I started with 1:1,5:2 but from there I tuned the circuit. You can just remember that the feedback should have less turns than the "primary" and "resonator" the primary should have more turns than the feedback but not more than the resonator. I tuned my feedback by just moving the connection further down that means i will have less losses in my grid resistor. If you want to tune your primary and resonator however than you can put an small metal object on your chicken stick. Than you ignite the flame and put the metal pice closer to the breakout or even touch it with the metal pice completely. If you can see that your flame gets bigger than your coil is out of tune and you bring it to tune by adding capasitance with the metal pice. If you know that you can move your Anode conetion in your coil down. That will add inductance and capasitance and your coil will be In tune.
@@motness Great, thank you:)
@@firefox1136 no problem.
If you have other questions feel free to ask.
🔥⚡⚡👍
Hey are you still alive?
You dont respond to any of my messages
Can you not put an independent earth rod outside?
Yes you can and I also did. But with small coils like this one it's not necessary. I plan to build an 10kva HFVTTC in that range a grounded rod would make sense.
@@motness Is that circuit diagram complete - You have used the same values - just ai have a similar tube and wanted to make another HFSSTC & VTTC? 👍
Yes that circuit is the final version and everything is the same as in my coil. If the tube is similar you can exactly copy the schematic. Maybe you don't need the 15pF impedance matching cap but you can just test that
@@motness actually it is different but similar construction 5868 - TB4 /1250 Triode
@@Jonodrew1286 I just looked into the datasheet of you tube. It can only do 4kv anode voltage so I would stick with one MOT like I did. Maybe two MOTs in parallel.
Yeah so big flamme