Hello group,
Today I am sharing a document which I think is of great importance. I found this while trying to do some research on how things were done in the past, I mean way in the past before transistors and silicon microchips were everywhere. How many of you know off the top of your head how wave rectification was done before we had our beloved diode?
This document will explain pretty much everything you could want to know. Now I know how Mr. Bedini knew to make the copper oxide semi-conductor for the crystal batteries. It turns out this was a very common part in radios prior to the 1960's. I am going to try and make a stack myself and I will post here at a later time (waiting on parts). This all goes along with my original idea to make the machine that this thread is about work without transistors or modern silicon parts. I have done some work on the machine and am running it on mechanical relays currently and want to try replacing the diodes with some copper oxide stacks.
Anyway here is a link to the document, it is a large file and I am hosting it externally from the forum.
Link:
https://1drv.ms/b/s!AmzmftzD-V0mhwTz-FNYfYZPiffa
Announcement
Collapse
No announcement yet.
New Medium Sized Machine
Collapse
X
-
Originally posted by min2oly View PostIs this it:
[ATTACH=CONFIG]5617[/ATTACH]
Of course there are more coils but I explained that and commented on how that is different. I will just say for convenience that they are all on the same single switch so you do not have the types of issues you could have with base resistors slightly off or mis-matched BJT's etc.. The coils are all the same length and measured of equal resistance but that is less relevant because they are all joined parallel to the same junction points.
RS there are a lot of differences but in many ways it is the same. There is no trigger coil for example so you do not have the same interplay between the power and trigger windings. Also as a result of not using a trigger winding and using a wheel and reed instead your trigger time is fully adjustable, meaning on a regular setup the trigger is fired via induction of the main wheel so there is a relation to the main rotor's rotation and degrees from the coil which is shared by the power and trigger, with this setup you can just back or advance the timing wheel however you like. I showed in that long video a bit about that.
Another potential difference going with something like this is the starving base issue with large setups or weak trigger coils. You know how if you have to many transistors and your trigger winding will just get to a point where is will not provide the current for all of the BJT's trying to fire their base from it, well FET's use hardly nothing so you would never be limited by your base current ( or lack of). I could go on and on pointing out how this is not exactly the same but I do not want to open new can of worms so I will leave it at that.
I will say again that this has never been an attempt to "do it better" it is only a way to do it different.
*EDIT*
Patrick just a side note that if accuracy is what we are after you forgot the diode on the common ground return,,, but I'm not nit-picking you, again thanks for doing that.Last edited by BobZilla; 11-27-2016, 08:44 PM.
Leave a comment:
-
not meant as a attack on you Bob, but once again, show me a Schematic, so i can see how it is different from a standard SSG...... A work around is always GREAT......
Leave a comment:
-
Hi RS,
I am at the point where I just don't think we will see this the same. If you care to understand I urge you to ponder on what I have said about where the inductance is living in this arrangement, I think you have focused so much on the flyback diode that you have not registered what I have been saying. I attempted to show you by putting an additional flyback diode on the circuit just in case there was or was not an internal one we could see that because of the inductance position in the circuit it does not push back to the SSR anyway.
We already commented on the pictures from the data sheet but I will point out to you again that it clearly says a flyback diode must be used and shows an external one diagrammed. I found this paper put out by crydom specifically about adding a suppresor, my only point is that if it already had one then why do they draw an external one and write papers to explain the need for adding one. As I said it does not matter to me if it has it or not anyway, I added one to prove that point.
Link:
http://www.crydom.com/en/tech/newsle...put%20ssrs.pdf
I just want to go back to how this all started and say that the point was never about if there is a flyback or not. I had just got done telling the group that I have used SSR's plenty. You came in and warned everyone not to use them and explained with big capitols about how they will kill the spike and explained the basic mechanics of the spike. Well justified or not I took a little offense at that because the way you spoke made it seems as if what I had just said could not possibly be true and one could deduct that I must not even understand how and where the spike comes from or where it goes. I don't think you meant it as an attack and still don't but it put me on defense because I know very well what I am doing and felt that I should set that notion straight.
In the end it is not about a flyback or not. It is about me showing you and everyone else how to work around that little problem you spoke of in the beginning, that is what is valuable here. I hope you and I will not have any animosity after all of this. As I said from the start I respect you and your knowledge.
Leave a comment:
-
Hi Bob,
Sorry I took so long to respond.....
Here is the Data sheet link for your SSR D1D40, and it does have a Free Wheeling Diode across the Source /Drain, along with a Snubber Cap, as most all SSR's have inside them...
http://www.crydom.com/en/products/catalog/1_dc.pdf
the diode inside, is in the same place as where JB puts the neon to protect a BD or MJL transistor......
If it is working for you, than great it works...... and I still think that the reason that it's working, is that the Output diode is much faster than the internal Free Wheeling Diode...... (OK, I was looking at the data sheet again, and noticed that the Free Wheeling Diode is a Zener Diode, and you may not be creating a high enough Back Spike to Trip it, as that is a 100V part and most neons glow at 60V or so)
The neon you show seams to be after the output diode, Put a neon in place of the diode you added, and I bet it glows, showing you that there is still energy there that the Free wheeling diode and Sunbber cap have the potential to dissipate the Back SPIKE as they are designed to do, and why they are not recommended .......Last edited by RS_; 11-27-2016, 12:37 PM.
Leave a comment:
-
Here is one more short video that I hope will clear this up. If not I don't think I can say anything any different.
It is a very short vid this time, not me droning on and on.
https://1drv.ms/v/s!AmzmftzD-V0mhnnM7ZrgnkpeeeHe
Leave a comment:
-
Originally posted by RS_ View PostBob, that you can make it go with a SSR is a good thing, the more ways to skin the cat the better, every one can learn from this... I want to understand what you have done different, that you are trying to explain, by sayng that the SSR is not under a Load....??????
Please look at the video ( the recent one) again, not the whole thing if you don't want but when I explain this bit of the switching.
Lets try a different understanding here. forget the SSR for a moment. Where would you install a flyback diode on just a coil or a motor??? You would put it in opposite direction of normal current and LOOP it back to the other side of the coil,, they go across the inductor backwards to LOOP the spike back through the inductor over and over until it is dissipated when a circuit shuts off. The key understanding here is that a flyback goes across the inductor.
What I have been saying all along is that the inductor IS NOT LOADING BETWEEN the SSR. If I wanted to actually put a flyback on my coils it would go from the bottom of the coils where they come into the SSR to the beginning of the coils over on the other side at the primary positive to form a reverse return path (a LOOP) around the coils for when they collapse.
*edit* additional comment
Also it might help if you really take notice of where the source is connected. I do not have the battery between the SSR either, look at that picture I posted after patricks, that is how most people would connect the source but that is NOT what I am doing. Look this is a trick that I have tried to share but I guess it is not understood. The information is there but you have to look.Last edited by BobZilla; 11-26-2016, 09:58 AM.
Leave a comment:
-
Ive moved over to a new thread called mechanical switching. hope to see you there.
Leave a comment:
-
Bob, that you can make it go with a SSR is a good thing, the more ways to skin the cat the better, every one can learn from this... I want to understand what you have done different, that you are trying to explain, by sayng that the SSR is not under a Load....??????Last edited by RS_; 11-26-2016, 12:48 AM.
Leave a comment:
-
Originally posted by RS_ View Postok Bob,
show me a Schematic of what this circuit is, so I can understand how it is different from a standard SSG, just using a SSR in place of a MJL.....
I will try to put together some drawings for you RS, I get that you would want to see it in that form and I dont mind trying to draw it out for you. It does have some differences but mostly it is the same my friend and that is the point really. You had made a comment that SSR's suppress the spike so don't use them (paraphrasing here) and I felt obligated to show how I run on SSR's and know how to not kill the spike.
You said how is it any different though,,, So it is a little different but yea it is a close replacement. The main thing to realize about this current setup is that all the coils are firing exactly the same time because it's a central switch. Basically as if you ran one transistor with multiple coils into the collector,, Heh actually I know John K does that alot. Anyway what else is different well its basically a FET inside so the trigger is very low consumption and with the SSR it's an optical switch.
Leave a comment:
-
ok Bob,
show me a Schematic of what this circuit is, so I can understand how it is different from a standard SSG, just using a SSR in place of a MJL.....
Leave a comment:
-
Originally posted by RS_ View Post...my only point, is that parts that have a fly back diode are not recommended for SG or SSG, that is all.......
A flyback diode would recirculate a reverse current on an inductor between the + and - of the SSR pins 3 and 4 (output) WE HAVE NO LOAD CONNECTED THERE.
Leave a comment:
-
Look, I see it does work..... i never said it did not, and it's always good to be able to hack different kinds of parts to do all this with..... I have used all kinds of parts to build Bedini stuff..... my only point, is that parts that have a fly back diode are not recommended for SG or SSG, that is all.......
Leave a comment:
-
Originally posted by BobZilla View PostI'm sorry guys that was not called for, I am just flustered because I know it works as I say and that seems to be called into question in front of the world here.
Leave a comment:
Leave a comment: