Video

Rognkjeksen fra tidligere ved 3:42 i videoen, jeg svømte rett over den.

Ok 👌🏼 kan du fridykke i eikern?

I didn't really think of water tightness being the major improvement until you mentioned it, but yes, it is improved water tightness. This version is built in the same manner as the OpenROV project, which claimed 100 meters of operating depth, so depth shouldn't be an issue. What I had previously considered the main improvement was usability. The first versions needed a laptop with USB cables, which was clumsy at best while in a small boat, coupled with unreliable software which made things a nightmare. This ROV is quick to start, everything always connects, and it is rather practical in use. The improvements I miss now are related maneuverability under water.

It should work with a beam tetrode, you're sure the tube is connected correctly as a tetrode instead of a pentode like I used? Altering component values should work as long as they are roughly the correct values. Some tuning is needed anyway, especially if changing tube. You didn't omit anything though? Are you able to measure anything with a frequency counter near the coil? It might be oscillating without achieving break out.

@@uzzors2k Thanks for the quick reply! What differences do I need to make when using a tetrode? The component values are close enough, although the coil isn't great. Yeah, I realised I would need to tune, but I expected something, even just oscillating, to happen. I didn't omit anything, no. I have my oscilloscope (granted, it's analog) with a single loop on the probe. It measured nothing, however I changes the jam jar lid capacitors for a feed back loop (loop connected to the 10nf 16kv feedback cap) and something did appear on the oscilloscope, however it did not look like the 10-20MHz sine wave I expected, and still no breakout was possible. It also continued to draw a lot of power.

@@albatross_v2 I'm no expert on tubes, but I imagine the screen biasing approach might need to be different, and probably need some tuning to get the correct voltage. I would also try different feedback methods. I think the spacing and geometry of the jar lid feedback capacitor was finicky to get right, and absolutely crucial.

@@uzzors2k Alright, I will try different methods of screen biasing and feedback then. Thanks for the help!

Quick update: It works! I've done some messing around with the feedback system (now using a loop) and got a nice flame of around 15cm. The two 4x150a tubes I have are both faulty in some way, one doesn't oscillate properly, and the other has a small amount of air in it (but still works well enough). Changing the FBR to a single diode changes the output flame shape. Frequency seems to be around 27MHz. I'll upload a couple videos to my channel later.

I'm not entirely sure. Either the feedback signal is too weak until breakout is acheived, or a nucleation point is needed for plasma to form. Once plasma has formed, it is self-sustaining due to it's high heat and conductivity.

Thanks! The ground symbols in the schematic are tied to mains ground, and also to 0V on the 16V supply. The "Power Ground" node is left floating, and serves as the return line for the "15 - 50V" node. The "15 - 50V" node also goes to the "Output Voltage Feedback" node. I see now that the schematic isn't exactly clear. I think an improvement would be to disconnect mains ground from the 16V and "15 - 50V" node returns, leaving these circuits floating. Instead mains ground should be tied to the "Power Ground" node, since this is the point which is exposed externally in the system.

Lengere sør. Vi begynte i Kollvika, og svømte ut til øyene som ligger noen hundre meter fra land. Det kan være mye strøm når man kommer litt ut fra stranda, så det lønner seg å komme ved flo eller fjære. Noen av filmklippene er fra Pålsholmen.

Yeah, you can run it at any frequency you want. But the coil dimensions, and class E stage parameters will need to be tuned to match the change in frequency.

@@uzzors2k Thank you for the information😊

My old host 4hv.org has been having issues for the last two months, and I'm not sure when/if it'll be fixed. I purchased a domain and new hosting last month however. My website is online at uzzors2k.com with all the original content.

@@uzzors2k awesome, thanks.

I wound it myself. It's a polypropelyne pipe with wooden end caps to keep it from deforming. 0.2mm wire is wound around the entire coil, which is then varnished to keep the windings from unravelling once the coil heats up.

@@uzzors2k ans how you detected IT to your synth?

@@tymelomokepon5807 I designed and built a MIDI interrupter which converts MIDI data to on/off signals at the same frequency as the note being played. Check the video description, all the source files are available!

@@uzzors2k can i buy this somewhere?

MOT shunts were left in, I used the transformer without any modifications.

1.5kV is what you should supply the tube with on a general basis, but somewhere above 2kV is what I had at hand. There's a risk of the tube arcing over when running the anode voltage well over spec, and also an increased rate of internal heating. For short demonstrations like in the video this works fine however.