Testing the TK Tar Baby

[TinselKoala]

"Danger of the capacitor getting overcharged."

Ha ha ha...  Rosie Posie talks about capacitors erroneously.

TK:

Don't fret, I think it was about a year ago now that ZeroFossilFuel claimed that "within a week" he was sure that he would have his RomeroUK replication self running!

MileHigh

Well, to be fair, any cap can be damaged if its voltage rating is exceeded of course, but this is a "second order" effect: it's not simply charge, but the charge _pressure_ or voltage that does it.

But .99 specified a film capacitor (or stack, to get to 10 uF) and at 12 volts there should be absolutely no problem. And many film caps are "self-healing" and can tolerate a certain degree of surge damage without failing totally. And 10 uF will charge very quickly and shouldn't need to be charged slowly like, say, a 0.3 Farad bank would.

Hey, I am fretting.

Ainslie has repeatedly and very arrogantly told us that she would make fools of us all by proving that the scopetrace likes the one below are valid,  in a video AS SOON AS SHE GOT HER APPARATUS AND BATTERIES BACK.

And if she DOESN'T manage to reproduce it with a functioning, properly wired  mosfet.... that is YET ANOTHER fact that will totally invalidate the "papers" and require a complete re-run of the experimental trials.  Actually that is already the case, but this scopeshot issue is obvious and critical.

[TinselKoala]

Now... if she found a 10 uF electrolytic cap, say a 35 volt one.... and she decided to hook it across the whole battery pack... and managed to get it backwards to boot.... that would be fun to have on video.

Ever wonder why the cans of small electrolytics are generally scored on the top? It's so that they will rupture there, and eject their wrapped electrodes mostly upward, in a great spiral ribbon like a party favor.

[picowatt]

Well, to be fair, any cap can be damaged if its voltage rating is exceeded of course, but this is a "second order" effect: it's not simply charge, but the charge _pressure_ or voltage that does it.

But .99 specified a film capacitor (or stack, to get to 10 uF) and at 12 volts there should be absolutely no problem. And many film caps are "self-healing" and can tolerate a certain degree of surge damage without failing totally. And 10 uF will charge very quickly and shouldn't need to be charged slowly like, say, a 0.3 Farad bank would.

Hey, I am fretting.

Ainslie has repeatedly and very arrogantly told us that she would make fools of us all by proving that the scopetrace likes the one below are valid,  in a video AS SOON AS SHE GOT HER APPARATUS AND BATTERIES BACK.

And if she DOESN'T manage to reproduce it with a functioning, properly wired  mosfet.... that is YET ANOTHER fact that will totally invalidate the "papers" and require a complete re-run of the experimental trials.  Actually that is already the case, but this scopeshot issue is obvious and critical.

Her first response to the Q1 issue was that we don't know how to read a 'scope properly and that we must somehow factor in the "offset" numbers to get a proper reading.

Her second response was that the 'scope needed to be set to AC coupling to properly read the voltage applied to the gate of Q1 during the positive portion of the FG cycle.

Her third response was that the 'scope is only showing the output frequency of the FG and that it does not at all indicate voltage, particulary regarding the gate of Q1 (I believe that is what she was trying to say...).

None of these responses are accurate, or even make any sense.  Anyone familiar with the use of a 'scope would have to agree. 

Even LeCroy agrees that the'scope is indicating +12 volts on the FG output trace during the positive portion of the FG cycle.

The truth is that in FIG3, 6, and 7, the 'scope is indicating that a sufficient voltage is being applied to the gate of Q1 to turn Q1 on, yet no expected current flow from Q1 being turned on is indicated by the CSR trace.

Again, this can only mean that during the tests related to those captures Q1 was either disconnected, not connected as per the schematic, or was not functional. 

What is most startling is that no one on her "team" must understand 'scopes or schematics either, or they would surely agree and point this out to her as well.

[MileHigh]

There was a famous scandal, I think it was Nichicon electrolytic capacitors that were manufactured for a few years with an inferior electrolyte.  They failed prematurely and puffed up and oozed.  Something like "The great motherboard capacitor scandal."  I think it happened in the early 2000s.  I believe that it affected millions of motherboards.

[picowatt]

Now... if she found a 10 uF electrolytic cap, say a 35 volt one.... and she decided to hook it across the whole battery pack... and managed to get it backwards to boot.... that would be fun to have on video.

Ever wonder why the cans of small electrolytics are generally scored on the top? It's so that they will rupture there, and eject their wrapped electrodes mostly upward, in a great spiral ribbon like a party favor.

Now we don't want anyone poking an eye out..

In my younger years, electro's were not scored.  They could only vent by blowing the plug out the bottom or, if mounted on a PCB, (or in a vice) the can and inards off the top.  They were a lot more fun to shoot around the basement than the newer, "safer" ones.  Although you can stlill do some nice tricks with them as well...