I need help with a DRSSTC, in everyway possible? / Tesla Coils / Forums

Forums

4hv.org :: Forums :: Tesla Coils

« Previous topic | Next topic »

I need help with a DRSSTC, in everyway possible?

previous 1 2 3 next

Move Thread

LAN_403

Andri

Sun Jun 21 2009, 04:44PM

Registered Member #1533 Joined: Wed Jun 11 2008, 02:13PM
Location: ReykjavÃk, Iceland
Posts: 46

I'm sorry for keeping this thread afloat but I have a suggestion to make:
Perhaps there should be a noob section on the forums. This could prove beneficial to both parties. Novices could ask questions without fear of scrutiny and experts would be free from all the crud. I'm sure noobs can help noobs in a sort of a "the deaf leading the blind" manner.

Thanks for the hint on audio, Steve. :)

Update: I just made a zero crossing detector and now my DRSSTC is singing the mario theme. :D

Guyfrom7up

Sun Jun 21 2009, 06:28PM

Registered Member #817 Joined: Mon Jun 04 2007, 01:33AM
Location:
Posts: 15

quite honestly, I feel kind of bad asking these questions too, because they sound really dumb. I'm not asking for someone to hold my hand, I'm asking so that I don't get into a more than necessary dangerous situation. To Steve, I totally agree with you for the most part, for HV, if you need some basic stuff to explain to you, then you shouldn't try it. But everyone has to start somewhere, right? This seems like a great community, but I think some people's ego is getting ahead of themselves. In other forums, I don't mind holding people by the hand, walking them through stuff and what not (I'm mainly a digital hardware and program kind of guy), but whatever.

and yes, there should be a noob section ;P

Dr. Drone

Mon Jun 22 2009, 12:27AM

Registered Member #290 Joined: Mon Mar 06 2006, 08:24PM
Location:
Posts: 1673

Guyfrom7up

Mon Jun 22 2009, 01:42AM

Registered Member #817 Joined: Mon Jun 04 2007, 01:33AM
Location:
Posts: 15

ok, Dr. Ego. I realize you have a lot of experience, and I'm happy that you have had such great success. You suggest that I build some circuits from some schematics, and sure, I could do that. But what if I want to know the why behind a schematic? Sure, I can get the gist of a circuit by looking at it, but not completely. I know you are knowledgable, but please, stop talking down to me, it is not apprecieated and it's not why I posted this topic. Other members are being very kind and helpful, but you are being rash, and cynical. I did not come here to get critisized, I came here to get info.

Dr. Drone

Mon Jun 22 2009, 05:46AM

Registered Member #290 Joined: Mon Mar 06 2006, 08:24PM
Location:
Posts: 1673

Dalus

Mon Jun 22 2009, 06:38AM

Registered Member #639 Joined: Wed Apr 11 2007, 09:09PM
Location: The Netherlands, Herkenbosch
Posts: 512

Think Conner and Dr Spark are quite right.

Just start a new thread with info you found to verify it's ok. Then start building it once you get stuck start another thread explaining your problem. Sure people will give input then.

A DRSSTC is just a too complex thing to build when you need someone to hold your hand the whole way. That will just take too much time for us. Though we can pick you up when you fall and really need help. But only if you make clear to us what you've done and why.

Steve Conner

Mon Jun 22 2009, 10:54AM

Registered Member #30 Joined: Fri Feb 03 2006, 10:52AM
Location: Glasgow, Scotland
Posts: 6706

Well, I wouldn't go so far as "Dr. Ego".

My own experience of 4hv is that I've been a member for many years. When I was a student, and in my first job which to be honest was something of a dead end, I had plenty of time to chat with noobs and advise them on coil building. Except in those days our "noobs" were boy geniuses like Steve Ward and Jimmy Hynes, who were high school students at the time. Little did I know they would out-spark my ass later on.

Partly as a result of the fun I was having with high voltage, I decided to quit that job and follow a career in electronic design, inspired by the likes of Jim Williams and Bob Pease. That's been going really well, but now that electronics is my day job I don't really have the inclination to follow it as a hobby any more, I'd rather do completely different things and try to get some sort of a life outside of engineering.

I've met many other hardcore coilers online over the years that I respect, and we all keep in touch by e-mail, which could be Dr. Ego's "advanced section" if you like to put it that way. I just drop by here now and again to grump at noobs and edit some oversized images.

In a vain effort to stay on topic:
- Microcontrollers aren't used to control coils because of latency. If your coil is 100kHz, and your uC has a 5MHz clock, one clock cycle is 7 degrees of phase. If your algorithm takes 10 clock cycles to decide when it's going to switch, then it's already 70 degrees late. I'm sure a sufficiently l33t programmer could find his way round this using some sort of digital PLL, but so far it's not been done. If I had to do a digital SSTC controller, I'd use a FPGA running a digital PLL or a discrete-time version of Finn's Predikter.

- Finding "somewhat hard to find chips" is one of the basic skills you're expected to have before building a SSTC.

Dr Hankenstein

Tue Jun 23 2009, 11:54PM

Registered Member #1642 Joined: Sun Aug 17 2008, 11:36PM
Location: Black Canyon City
Posts: 96

Chris is absolutely correct! Just recently he called me on his voice activated phone and summoned me to his house; just to discover his head was stuck in the door between the lab and house. I immediately retrieved a plunger and some goose grease...just in a knick of time. His ego had his head swollen so much, another five minutes might have killed him! Yep, if you asked me, he has definitley earned it!

Hank

hvguy

Wed Jun 24 2009, 04:31AM

Registered Member #289 Joined: Mon Mar 06 2006, 10:45AM
Location: Conroe, TX
Posts: 154

I think itâ€™s important to learn how to build these devices via the â€œhands-onâ€ approach; if you're ready for it. There has been a major shift toward computer modeling and micro programming over the last decade that has many new coilers (or potential new coilers) wanting some sort of guarantee that itâ€™s going to work when itâ€™s turned on. This just does not happen that often with TCâ€™s (they donâ€™t have a â€œdebugâ€ command, yet

) and, combine with reliability, is really the wholly grail of HVPS or SMPS design. To spite what they are teaching in most high schools and colleges, not everything can be learned from a book, a simulation, or a forum. Get out there and build it. Then blow it up, find out what happened, and do it all over again. Then post waveforms and data here and everyone, even Dr. Spark (props for the honesty Chris), would be happy to comment. You know, this thread may turn out to be a very good â€œhow to use 4hvâ€ guide for noobsâ€¦

Advice regarding your questions:
-Turns donâ€™t matter, secondary frequency does. Keep it below 100KHz for a DRSSTC. Lower is better. D/H Aspect ratio of 1 to 3 to 1 to 5 workes well.
-The above also applies to toroids, bigger means lower F so bigger is better (thereâ€™s a limit here, of course).
-Voltage ratings, audio modulation, and IGBT driving are covered everywhere in the forum, so dig around, itâ€™ all here.

Good Luck!

Dr. Drone

Wed Jun 24 2009, 07:31AM

Registered Member #290 Joined: Mon Mar 06 2006, 08:24PM
Location:
Posts: 1673

previous 1 2 3 next

Moderator(s): Chris Russell, Noelle, Alex, Tesladownunder, Dave Marshall, Dave Billington, Bjørn, Steve Conner, Wolfram, Kizmo, Mads Barnkob