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Hi all. Gave a hint on this earlier, in a different thread. Starting a couple of weeks ago, I started to think about some things, while I was converting my "breadboard" interrupter to put in a case, I am always thinking, even when working on other things... I used to work as printer on newspaper printing presses for a lot years. Just left this industry for good a couple of years ago now. Dying trade. Besides running them, also worked on them. Lots of mechanical and electrical controls involved. In addition, used to work on all kinds of support equipment in mailroom department, which handles the papers after they come off the press. Again all kinds of mechanical and electrical controls. I started to think about rotary encoders on lots of different equipment we had. Then, I thought about SSR's (Solid State Relays), again on several different things. SSR's have been around for quite some time now. I started to remember, some types of SSR's have a zero cross trigger method. And it does this on the actual load, vs. the indirect method of the other 2 interrupters that I have modified and use on my VTTC's. Trigger on the actual load should be even better, since especially using a level shifted supply. This should work I thought. Then I thought about an encoder to use. The ones on machines there were used for feedback. I thought, about an encoder that was more convenient to use and thought about CNC machines that I have run before in the past. They have a rapid handwheel rotary encoder. The big plus is these have mechanical detent stops between the optical slots. So with just a little looking around, I found some very economical ones, just in case it does not work, so I would not be out much coin if I fail. When I got them in, I did a couple a very basic encoder output tests scoping it. Looked at the pulse width times and decided it is most likely going to work. Just another note, the detent stop is actually not "centered". Designed that way. At first I thought this was going to be a problem, then I realized it will not. Because of not being centered, when you initially turn the handwheel, because of the detent, one direction you get a "quick pulse snap". And the other you get a "longer pulse snap". Instantly, after looking at the pulse width duration on the scope, I thought "burst mode" in the long one. Cool! And a single shot in the short one. Can also achieve bursts by a quick flick of short ones, not quite as intense. Decided, since I was pretty confident, to put all of this in an enclosure from the get go, before even trying actually on the coil. Normally I would not do this, I would admit. I must say, it is working greater than expected. Trigger timing is great. Long straight swords. No shorter wandering problems, like the EVR one originally had and even the former breadboard one had when using a level shifted supply. Really neat to be in full manual control. The things you can do are so numerous. A very fun controller. Get lucky once in a while right out the gate... Since I was having so much fun, I have decided to give it a fun name, borrowing some from Greg Leyh's: Lighting On Demand big fellas coils :^) So I will call it: Swords On Demand Just a few more thoughts here. I suppose you could also use a regular encoder with a stepper motor and controller, or even fancier if you want, say a PLC or something else in conjunction with the SSR. Also, I suppose using this SSR with several other numerous devices to supply a "drive" signal to it. For me for now, I like the extreme simplicity of this setup. Just 3 economical parts and very easy to hook up :^) But I just today earlier, received a second SSR, to play with... Going to attach several pictures, some info, a quick crude drawing of the wiring, and a video of me running the coil with it. Links: https://photos.app.goo.gl/LDJkmHKtMqmHKg5f6 Video: https://photos.app.goo.gl/pxrJmxy9MttT1EHz6 Chris Reeland Ladd Illinois USA Sent from my LG V20 _______________________________________________ Tesla mailing list Tesla@xxxxxxxxxxxxxxxxxx https://www.pupman.com/mailman/listinfo/tesla