Search found 340 matches

by terri
Thu Nov 25, 2004 7:22 pm
Forum: General Discussion
Topic: Cooling fan thermostat
Replies: 16
Views: 3875

Re: Cooling fan thermostat

As long as you're going to use a relay anyhow, stop at any plumbing or furnace shop and beg for an old used 24 volt thermostat transformer. Wear old clothes and look poor. Chances are they'll just give you one.<p>Incidentally, it's amazing how many 110 VAC relays work just fine on 12 VDC with no ill...
by terri
Thu Nov 25, 2004 6:53 pm
Forum: General Discussion
Topic: SO8
Replies: 16
Views: 3843

Re: SO8

It's called the PON effect. You can't find something and turn the place upside down looking for it and gnashing your teeth amd rubbing ashes on yourself and finally you break down and go out to buy a new one and you come back with a shiny new one and when you walk in the door you trip over the one y...
by terri
Wed Nov 17, 2004 10:18 pm
Forum: General Discussion
Topic: strobe tubes
Replies: 11
Views: 2002

Re: strobe tubes

Well said! I'm impressed, Stephen! You sound like an OT like me. I built a studio light for myself a very long time ago, whence my limited expertise. I forget the joules, but it was a lot. Used to make a pretty good pop! when triggered. I used it sometimes to take pix of buildings and houses for fil...
by terri
Wed Nov 17, 2004 9:52 pm
Forum: General Discussion
Topic: Website on batteries ???
Replies: 5
Views: 994

Re: Website on batteries ???

Cf. "lead acid battery theory' question topic by windmiller.
by terri
Wed Nov 17, 2004 9:47 pm
Forum: General Discussion
Topic: lead acid battery theory question
Replies: 5
Views: 1523

Re: lead acid battery theory question

I don't know. I read about 1/3 of the way through and it looked pretty good to me. Maybe it's my own inexpertise? Only things I objected to in this 1/3 sample were:<p>"It's like 'making a blivet' (a blivet is 10 pounds of poop in a 5 pound bag). You have to force more electricity into a battery than...
by terri
Sun Nov 14, 2004 8:06 am
Forum: General Discussion
Topic: strobe tubes
Replies: 11
Views: 2002

Re: strobe tubes

Good point about the arc discharge in glow lamps, Stephen --there is much I have forgotten about gaseous discharge.<p>Without making a major research project out of it I did a quick search on Helicopter Searchlights, and my quick impression is that these are arc lamps. I can't see getting 60 to 90 b...
by terri
Fri Nov 12, 2004 9:44 pm
Forum: General Discussion
Topic: strobe tubes
Replies: 11
Views: 2002

Re: strobe tubes

I wonder if they are using decaying rf to excite the gas and if the the final glow near the electrodes is really only like the glow which appears at the electrodes of a regular neon bulb when it's running normally, rather than the electrodes actually being white-hot.<p>Over-exciting a regular neon b...
by terri
Sun Nov 07, 2004 7:17 pm
Forum: General Discussion
Topic: Thermo electric coupler
Replies: 8
Views: 2109

Re: Thermo electric coupler

Gee whiz, sorry! I posted an answer to the wrong topic. Ignore. New.
by terri
Sun Nov 07, 2004 7:16 pm
Forum: General Discussion
Topic: Thermo electric coupler
Replies: 8
Views: 2109

Re: Thermo electric coupler

Do you mean "thermocouple?" As in:<p>(A) The device which is stuck in a gas appliance pilot light and generates enough current thermally to keep the main gas valve open unless the pilot light goes out?<p>(B) The device used to measure temperatures ("thermocouples") electronically?<p>Both of these de...
by terri
Tue Mar 02, 1976 6:59 pm
Forum: Robotics
Topic: motion sensor
Replies: 5
Views: 3583

Re: motion sensor

Try an IR yard light switching system. I bought one of these from Ace Hardware (Ace 3038320) for about $10. It's for 110 V, but you can dismount the sensor head from the light fixtures, and somewhere in the head there's probably a power supply to operate the solid-state circuitry from the 110 V line...