# Recent content by TurtleMeister

1. ### Stargazing Macroscopic Dark Matter Revealed By Lightning

@phinds Apology accepted. I too was skeptical when I first read about this because like you I was thinking that dark matter cannot clump. But as others have mentioned, this is not about traditional dark matter. For those who are viewing the video, the disputed phenomena accurs at about 0:37...
2. ### Stargazing Macroscopic Dark Matter Revealed By Lightning

Well, I'm no expert on this but from what little I've read macroscopic dark matter is just what the name infers, dark matter that is not just single particles but has macroscopic form. Such an object interacting with the earth would be, for lack of a better term, a dark matter meteor or...
3. ### Stargazing Macroscopic Dark Matter Revealed By Lightning

Hi Dave. Yes, I remember that you disagreed. I too was skeptical when I first saw the video. However, after close analysis I could see that the light was coming through the foliage. The light turns green right at the bottom of the streak. That could be caused by the strike being very close to...
4. ### Stargazing Macroscopic Dark Matter Revealed By Lightning

This paper suggests that macroscopic dark matter could leave a trail of ionized plasma as it passes through the earths atmosphere. If this happens during a thunderstorm it could trigger a lightning strike that follows that trail. https://journals.aps.org/prd/abstract/10.1103/PhysRevD.103.063024...
5. ### Why does a capacitor charge to 63% of the applied voltage?

Thanks. That helps a lot. I'm not a math person and only use it as a means to an end for whatever I'm dealing with. I had heard of Euler's number before, and even unknowingly used the concept in calculating compound interest, but never studied it. So my guess about it being an irrational number...
6. ### Why does a capacitor charge to 63% of the applied voltage?

I understand your question, but I don't know the answer. I'm only responding because I find it interesting. It could be that this is just one of those "why" questions that physics is not very good at answering. Keep in mind that the 63% is an approximation. I don't know, but I suspect, that it...
7. ### Voltage across a Capacitor More than the Source Voltage?

DC power supplies can have a certain amount of ripple, spikes, and noise in their outputs. If you have only a capacitor without any load on the output, then the capacitor will eventually charge up the the maximum, or peak value, of the ripple, spikes, and noise. Two volts is a lot but not out of...
8. ### Television Engineering History

Back in the early 1970's I took a correspondence course in color tv servicing from NRI. If you looked at Jim's link to the Radio Electronics magazine issue you may have noticed one of their advertisements, which was usually included in every issue. One of the things I remember learning about in...
9. ### SpaceX SpaceX Falcon Heavy Launch

The return and safe landing of the side boosters was fascinating. This video shows how fast they're coming down before the rockets fire. Best if you use full screen with headphones.
10. ### SpaceX SpaceX Falcon Heavy Launch

This is great news. It's good to see this type of thing back in the mainstream news. Talk about the launch being at the same pad as Apollo 11 brings back memories. I was there in person back in 69 to watch it. I still have vivid memories of the sights and sounds.
11. ### Trouble with getting AM reciever to work

That's an interesting circuit. Is it your design, or where did you get it? This takes me back to my younger days when I would spend many hours experimenting with simple am receiver designs. However, I didn't have IC chips or SPICE. Just a junk box.
12. ### Trouble with getting AM reciever to work

Here's a close match to your circuit (if you move the diode to the front): http://www2.ensc.sfu.ca/~ljilja/ENSC220/Labs/lab_5.html
13. ### Trouble with getting AM reciever to work

I would move the diode to the front end for detection, as berkeman suggested, and use the op amp for audio amplification. Also use a germanium diode (such as the 1N34A) instead of silicon.
14. ### What was your first computer?

TRS80 model 1. I later added the expansion interface which gave me 16k of ram. I then added the 360k floppy drive for $500 and then the line printer for$1000 (the line printer was used).
15. ### B F=ma -- True or an Illusion...

The op may be confusing force with kinetic energy.