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  #21  
Old 10-04-2007, 12:33 PM
tfischer tfischer is offline
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Quote:
Originally Posted by CPMcGraw
You must have missed this one, Tim:

Name "Solar" dropped from packaging in 1988.

Upper left of catalog page.

BTW, the 88, 89, and 90 catalogs are posted on Ninfinger.

1988 Catalog

1989 Catalog

1990 Catalog


Ah, it was in a different directory structure than the other catalogs, so I missed them.

I'll edit my post above.

As yet another aside, I'm really depressed that the "new" packaging look dates back to 1988! That's almost 20 years for the look that I still consider "new"...

Thanks,
-Tim
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  #22  
Old 10-04-2007, 12:41 PM
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kurtschachner kurtschachner is offline
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Quote:
Originally Posted by tbzep
Oooh....resistance fuse wire!

Maybe I should have said, just a patented piece of nichrome.



Sorry, my point was subtle and only found if you read the document (or hear it from Vern which was my case). The Astron igniters have a thinned-down section under the pyrogen which localizes the heating area. Vern somewhere (NARCON??) discussed the machine that was made to create this thinned area.
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  #23  
Old 10-04-2007, 01:32 PM
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Quote:
Originally Posted by kurtschachner
Sorry, my point was subtle and only found if you read the document (or hear it from Vern which was my case). The Astron igniters have a thinned-down section under the pyrogen which localizes the heating area. Vern somewhere (NARCON??) discussed the machine that was made to create this thinned area.


They were 30 ga with a thinned area and then sometime in the mid 1970's they stopped making them that way and switched to straight 31 guage with the pyrogen on it. They worked about as well, but the thin section was neat-o since it formed a nice bend easier.

I used them with a wadding ball crammed in (Proto-plug) with nearly 100% success rate in thousands of launches.

I now use bare nichrome wire with the loop formed around a straightened paper clip and hold them in with a plug and a small square of wadding to prevent melting of the plug. Again: nearly 100% success rate and far more reliable than the breakable standard igniters. I use a car battery most of the time, but they work fine with a 6 volt alkaline lantern battery, so if anyone has a Quest controller with a "EBC" give it a try. For clustering, hook up 2 lantern batteries in parallel for the same voltage and more amps. The Quest controller will handle 12 volts, so batteries in series will work as well.
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  #24  
Old 10-04-2007, 03:10 PM
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Quote:
Originally Posted by Shreadvector
They were 30 ga with a thinned area and then sometime in the mid 1970's they stopped making them that way and switched to straight 31 guage with the pyrogen on it. They worked about as well, but the thin section was neat-o since it formed a nice bend easier.


That would explain why I'm not familiar with the thinned Astrons. I didn't get into rocketry until the mid 70's so I never saw the neato version.
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  #25  
Old 10-05-2007, 08:22 AM
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Quote:
Originally Posted by Shreadvector
For clustering, hook up 2 lantern batteries in parallel for the same voltage and more amps.
Hmm, this would seem to violate Ohms law...
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  #26  
Old 10-05-2007, 10:21 AM
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Hah? You always connect batteries in parallel when you want greater current capacity. You are thinking in terms of an ideal power supply, where the current always tracks exactly with the resistance and voltage. Just because you have a given resistance and a given voltage of battery doesn't mean that you will get the calculated current when you hook it all up... if that were true, you could hook up a single AA cell with a centimeter-thick copper conductor and get more than 200,000 amps of current. The battery just can't pump out electrons that fast.
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  #27  
Old 10-05-2007, 11:34 AM
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Default Paralleling batteries lowers resistance

Quote:
Originally Posted by Solomoriah
Hah? You always connect batteries in parallel when you want greater current capacity. (snip) The battery just can't pump out electrons that fast.
Yes, that's true. We model that as output resistance. In this, a thevenin model, each battery is modeled as an ideal voltage source in series with an output resistor, Ro.



In the top pic, the load current is the result of the voltage divided by the sum of the output resistance and load resistance.

In the bottom pic, with two batteries in parallel, the output resistances are also parallel. Thus, the net resistance seen is lower, resulting in higher current to the load.

HTH.

Doug
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  #28  
Old 10-05-2007, 11:17 PM
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Point taken, but these are lantern batteries we're talking about. What's the actual increase in current when used with 3 estes igniters? More importantly, how much power is being delivered to each igniter with 2 6v lantern batteries in parallel vs series?
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  #29  
Old 10-06-2007, 10:43 AM
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Quote:
Originally Posted by PaulK
Point taken, but these are lantern batteries we're talking about. What's the actual increase in current when used with 3 estes igniters? More importantly, how much power is being delivered to each igniter with 2 6v lantern batteries in parallel vs series?
Good question. And on that point, I would have gone the other way. While two batteries in parallel have lower output resistance, if it was low enough already, then paralleling wasn't necessary. In which case, putting them in series to get 12V is likely more effective, especially for clustering. And that's how I used my two 6V lantern batteries before upgrading to a 12V lead-acid battery.

Doug
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  #30  
Old 10-06-2007, 08:55 PM
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Quote:
Originally Posted by tfischer

As an aside, anyone remember the Power Pulse launcher? When it came out I was a little jealous that I had the now "second-rate" Solar controller. But looking back, that Power Pulse thing was just odd. Can one even get those weird Polaroid batteries anymore?

-Tim


I bought, and still have my Power-Pulse controller. The batteries really worked very well as compared to the 4 AA Solar controller I had. My local hobby shop had a large stock of the batteries back in the early 90's which I bought up. And I believe if you can still get polaroid film the battery in the pack is the same.

With regards to the solar ignitor issue...Wasnt the solar ignitor supposed to be used with 6 volt systems and the other ignitors used with 12 volts like a car battery? That was always what I heard....
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