Search found 340 matches

by terri
Thu Dec 27, 2007 10:32 pm
Forum: General Discussion
Topic: 6v battery indicator
Replies: 13
Views: 3572

ADDENDUM

(Inadvertently omitted)

If one LED is lit, the camera will run, but for a time
depending on where the user wanted the setpoint set.
by terri
Thu Dec 27, 2007 10:26 pm
Forum: General Discussion
Topic: 6v battery indicator
Replies: 13
Views: 3572

Derek said: "I built a 4 D-cell battery pack to run my digital camera, but I am now using a 6v 7.2Ah lead-acid battery. I am trying to find a simple schematic using LEDs (maybe red-yellow-green?) to display the battery charge status when I press a momentary pushbutton. Any ideas? Thanks...." I apolo...
by terri
Thu Dec 27, 2007 1:33 pm
Forum: General Discussion
Topic: 6v battery indicator
Replies: 13
Views: 3572

Well, you still have to know your setpoints, even if it's going to measure open circuits. I don't know why people automatically go to integrated circuits to solve a simple problem like this. All you need is a voltage divider with three taps, with the LED limiter resistances figured into the taps. Oh...
by terri
Thu Dec 27, 2007 4:55 am
Forum: General Discussion
Topic: 6v battery indicator
Replies: 13
Views: 3572

Battery status with a load or without? (Open circuit or running the camera.) How big a load? What voltage cutoff points are you looking at for "status?" (At what point will the camera quit?) Is there any way to connect directly to the internal battery connections in order to use the camera's battery...
by terri
Tue Dec 11, 2007 9:48 pm
Forum: General Discussion
Topic: Thermal Anemometer Design for automotive HVAC - ?
Replies: 10
Views: 2491

Addendum re 1157 bulb

I just realized that you may have thought that an
"1157" may have been some kind of integrated bridge
circuit.

No. It was just a standard 1157 automotive lamp with the glass broken away.
by terri
Tue Dec 11, 2007 9:32 pm
Forum: General Discussion
Topic: Thermal Anemometer Design for automotive HVAC - ?
Replies: 10
Views: 2491

Robert Reed queried: "That sounds interesting. How had you planned to keep the other side of the bridge (1157) out of the moving air mass." Just by wires, with the remainder of the bridge out of the air flow. The additional resistance of the lead-out wires could be balanced out by adjusting one of t...
by terri
Tue Dec 11, 2007 1:29 pm
Forum: General Discussion
Topic: Thermal Anemometer Design for automotive HVAC - ?
Replies: 10
Views: 2491

I broke open an 1157 (12 volt) bulb and ran a constant 2 volts across it and measured its resistance by the current flow. More air, less temperature, lower resistance. I had to fiddle with externals a little to get it in the flow range I wanted. Had I wanted to get more sophisticated, I could have s...
by terri
Wed Sep 28, 2005 10:51 pm
Forum: Computer Programming
Topic: Waterlevel controller
Replies: 8
Views: 4089

Re: Waterlevel controller

Back in the late '60s I used a CK-722 germanium junction transistor in the common collector configuration to sense water level directly. The input impedance of the common collector configuration is very high, and the output impedance very low, so all one needed was a power supply, a moderately-sensi...
by terri
Tue Sep 27, 2005 8:02 pm
Forum: General Discussion
Topic: Go stand in the corner, Chris
Replies: 74
Views: 12822

Re: Go stand in the corner, Chris

Mike:<p>I disengaged from this a long time ago after the physics discussion emerged again.<p> I point out again that I did not at any point, anywhere on this board, get involved in the energy-mass equivalence debate. Not once. <p> My original intent in starting this topic was to advance the idea tha...
by terri
Sun Sep 25, 2005 9:39 pm
Forum: General Discussion
Topic: Go stand in the corner, Chris
Replies: 74
Views: 12822

Re: Go stand in the corner, Chris

More evidence above.
by terri
Sun Sep 25, 2005 9:21 pm
Forum: General Discussion
Topic: Go stand in the corner, Chris
Replies: 74
Views: 12822

Re: Go stand in the corner, Chris

I say again: I never discussed any physics book or the famous equation*. Once again, his monomania is getting in the way of rational thought processes and normal socialized behavior. <p>I told you his responses would be the best evidence of his abuse of free speech.<p>Notice the monomaniacal behavio...
by terri
Sun Sep 25, 2005 7:17 pm
Forum: General Discussion
Topic: Go stand in the corner, Chris
Replies: 74
Views: 12822

Re: Go stand in the corner, Chris

You're a sick man, Chris. Go see a doctor.
by terri
Sun Sep 25, 2005 1:56 pm
Forum: General Discussion
Topic: Go stand in the corner, Chris
Replies: 74
Views: 12822

Re: Go stand in the corner, Chris

What's really tragically funny about this is that I never once mentioned anything about mass/velocity relationships.<p>He's got me mixed up with someone else.<p>I mentioned that his response to this topic would be the best evidence of the abuse of his right of free speech.<p>Chris. See your doctor.<...
by terri
Sun Sep 25, 2005 7:01 am
Forum: General Discussion
Topic: Green Laser pen
Replies: 71
Views: 9231

Re: Green Laser pen

by terri
Sun Sep 25, 2005 6:18 am
Forum: General Discussion
Topic: Go stand in the corner, Chris
Replies: 74
Views: 12822

Re: Go stand in the corner, Chris

"We must look like squabbling schoolboys to newcomers."<p>Exactly. Whence my suggestion.