Search found 340 matches

by terri
Sat Sep 17, 2005 11:14 am
Forum: General Discussion
Topic: News Story Static Electricity
Replies: 4
Views: 1054

Re: News Story Static Electricity

In the spirit of hunting down and killing variables, and as a mental excercise:<p>One of the problems science faces is that so many scientists tend to dismiss that which they cannot explain. William James had some comments about this over a century ago, but I'll let that go for now.<p>So let's appro...
by terri
Sat Sep 17, 2005 9:41 am
Forum: General Discussion
Topic: A very newbish question about non-plarized caps
Replies: 16
Views: 3422

Re: A very newbish question about non-plarized caps

That was a direct copy and paste, with premeditated loss of a lot of formatting.<p> That's, incidentally, why I try to avoid a lot of the whells and bistles of this or that word processor. I rarely use things like quote boxes and the like, and if you'll notice, I use dF and dC for degrees Fahrenheit...
by terri
Sat Sep 17, 2005 3:17 am
Forum: General Discussion
Topic: A very newbish question about non-plarized caps
Replies: 16
Views: 3422

Re: A very newbish question about non-plarized caps

I DID NOT CAPTURE ANY ILLUSTRATIONS, BUT THIS IS FROM THE MASTER:<p>Dean Huster Charter Member Member # 12<p> posted February 22, 2005 04:38 PM Well, at the risk of overloading the forum, I'll post this answer. Granted, it's an overkill for the question, but this question arises so often that maybe ...
by terri
Thu Sep 15, 2005 4:56 pm
Forum: General Discussion
Topic: The SPUD has left the building
Replies: 10
Views: 1586

Re: The SPUD has left the building

Rope.
by terri
Wed Sep 14, 2005 3:01 pm
Forum: General Discussion
Topic: where does the power go?
Replies: 80
Views: 17302

Re: where does the power go?

I wish you'd said that before and saved me the embarrassment. :)<p>[ September 14, 2005: Message edited by: terri ]</p>
by terri
Wed Sep 14, 2005 8:57 am
Forum: General Discussion
Topic: truck battery to 12vdc regulated supply
Replies: 46
Views: 7969

Re: truck battery to 12vdc regulated supply

Yikes!<p>Who answers the cell phone?
by terri
Wed Sep 14, 2005 8:48 am
Forum: General Discussion
Topic: where does the power go?
Replies: 80
Views: 17302

Re: where does the power go?

OK, I'm going to admit error and say 5HP for the fan is too much. I took a quick look at the Machinist's Handbook on the way out the door to catch the bus and a single V-belt in this kind of situation can only transmit about 2.73 HP.<p>I missed the bus.
by terri
Wed Sep 14, 2005 6:01 am
Forum: General Discussion
Topic: where does the power go?
Replies: 80
Views: 17302

Re: where does the power go?

OK, that's one vote for the "misread decimal," with a comment that 5HP to run the fan through a single belt is too much --and is more like 1/4 to 1/2 HP.<p>I recall that the monstrous VW cooling fan was about 15-18 inches in diameter and ran about 3/4 of the engine RPM, judging from a poor visual re...
by terri
Tue Sep 13, 2005 9:57 pm
Forum: General Discussion
Topic: truck battery to 12vdc regulated supply
Replies: 46
Views: 7969

Re: truck battery to 12vdc regulated supply

Where are you driving this rig with all that entertainment stuff?<p>I want to know so I can avoid the roads in that part of the country.<p>[ September 13, 2005: Message edited by: terri ]</p>
by terri
Tue Sep 13, 2005 9:48 pm
Forum: General Discussion
Topic: where does the power go?
Replies: 80
Views: 17302

Re: where does the power go?

So what's the vote? Was the "5 HP" a mis-read decimal, or did it include the fan, which runs off the same belt?<p>Seems to me about 5HP would be about right for running one of those big VW cooling fans with the cooling flaps full open at 50-60 mph.<p>My vote is that the quoted specs included the fan...
by terri
Tue Sep 13, 2005 1:23 pm
Forum: General Discussion
Topic: How to size Transformer
Replies: 21
Views: 4054

Re: How to size Transformer

Do you mean the lens, the mirror, the bulb, the Q665, or the IGBT?
by terri
Tue Sep 13, 2005 12:29 pm
Forum: General Discussion
Topic: Generate 7w of electricity by walking
Replies: 33
Views: 4651

Re: Generate 7w of electricity by walking

I remember in college a friend of mine got himself a brand new Austin-Healey Mille Miglia, and when he was asked how much horsepower it had, he'd say (with suitable pseudo-snottiness and a heavy British accent), "Oh we don't rate these motor cars in horsepower [/b]. We use furlong-stones per fortnig...
by terri
Tue Sep 13, 2005 12:13 pm
Forum: General Discussion
Topic: How to size Transformer
Replies: 21
Views: 4054

Re: How to size Transformer

Don't they sometimes send the beam through a pool of water to cool it or something like that? Seems to me Theatre Projectors do or did something like this --but maybe that was just with the limelight illumination or maybe with carbon arc lamps. My recollection on this is vague.
by terri
Tue Sep 13, 2005 8:30 am
Forum: General Discussion
Topic: How to size Transformer
Replies: 21
Views: 4054

Re: How to size Transformer

The aforementioned ARRL handbok has a lot of info on transformers in the Power supply section, including a graph of watts versus transformer core cross-section.
by terri
Tue Sep 13, 2005 6:16 am
Forum: General Discussion
Topic: How to size Transformer
Replies: 21
Views: 4054

Re: How to size Transformer

Someone's sure to challenge you on the use of lamp dimmers on the supposedly "inductive" transformer primaries.<p>This actually works pretty good, within limits, and the actual load is the resistive load of the lamps "reflected" through the transformers.