Looking for a more reliable launch controller

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Glad to hear it, I actually just bought two more a few minutes ago.

I have been considering The LiPoly batteries, do they plug into the receptacle in the battery compartment directly or do you need a special connector? Do they fit in the compartment easily? Is it worth the money for four batteries and a charger? Duracell C batteries are reasonably cheap at Costco and are pretty well proven.

Unfortunately, 4 C cells won't quite do it. It requires 6. But 6 Energizers will last you 100's of launches I am told.
 
For what it is worth, I actually built my own launch controller for about $30 in total parts and about 30mins of soldering. It uses two 9v batteries in parallel, a key switch, an arming switch (complete with red missile switch cover, of course :cool: ) with ultrabright LED and a loud piezo buzzer, and a momentary switch. I used 6m of shielded speaker wire with some alligator clips, and we were off to the races.

The only thing I had to rummage for was a key lock switch where the key could NOT be removed in the on position.

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Overall I am pretty happy with it, and it came in at only a few dollars more than an entry level one from the hobby shop...

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Good job snrkl. I had intentions of making my own last year and had even purchased all the requisite pieces/parts (- speaker wire), but not being very electronically inclined, I decided to pass and bought my Lightsword II instead. The only thing I would have done different in yours is to add my 12V/7A battery instead of your 2 9V batteries.
 
I did a fair bit of reading on what current was needed to fire the igniters.. Seems that most of the igniters I read up on for LPR will fire with 1Amp... the 9V's were mostly chosen as they are cheap and available, would run the piezo, together kick out the needed 1A, and I had a pair of 9v battery clips left over from some other projects...

So far we've used it for a half dozen local oval launches in the last month (restricted to 400ft here) so we haven't had to change the batteries yet...

@Tangojuliet out of interest, what are the dimensions/weight on the 12V/7A battery?
 
I did a fair bit of reading on what current was needed to fire the igniters.. Seems that most of the igniters I read up on for LPR will fire with 1Amp... the 9V's were mostly chosen as they are cheap and available, would run the piezo, together kick out the needed 1A, and I had a pair of 9v battery clips left over from some other projects...

@Tangojuliet out of interest, what are the dimensions/weight on the 12V/7A battery?

I was just thinking that with my battery, it holds a charge much longer, and is easily re-charged when needed. Besides that, I guess there's really no need for the bigger battery. By chance, I have the dimensions with me because I'm looking for a small box to carry the battery in rather than just hand-toting it and the launcher separately all the time. It is approximately 2 5/8" x 6" x 4". Weight-wise, I'd guess it to be almost three pounds, +/-.
 
hehe.. your battery is larger than my whole controller!! I think it's a little overkill for what I need... ;)

As for wireless, i wanted simple and safe - once it goes wireless, then there are a WHOLE host of other things to take into account....
 
Incidentally, don't be afraid of the electronics.. it is actually SUPER easy.. adafruit has some excellent intro videos to soldering and much of the basics - the soldering one is here:

[YOUTUBE][video=youtube;QKbJxytERvg]https://www.youtube.com/watch?v=QKbJxytERvg[/video][/YOUTUBE]
 
I can solder fair enough, but my real problem is the understanding of it all. I never had a class in electronics so it gets over my head real quick when you start talking about Amps, Watts, Volts, Ohms, Resistors, etc. I don't know or understand the relationships of all that stuff. I could put together the pieces, but designing or modifying someone else's design would never happen.
 
Unfortunately, 4 C cells won't quite do it. It requires 6. But 6 Energizers will last you 100's of launches I am told.

I wasn't very clear... I have four controllers (well, two of them are shipping today) so I was wondering if it would be worthwhile to buy four of the fancy LiPo batteries to replace the 24 C batteries.
 
I wasn't very clear... I have four controllers (well, two of them are shipping today) so I was wondering if it would be worthwhile to buy four of the fancy LiPo batteries to replace the 24 C batteries.

Initially, I would say yes, but that is really dependent on how often you use the controllers and how often you'll need to replace the C cell batteries. Four LiPo batteries and the necessary charger and cables can be pricey up front. Another thing to consider are the hazards of charging LiPo's. If you're not careful about the settings on your charger and the capacity of the packs, they can easily catch fire. And they need to be maintained a certain storage capacity when not in use. I've heard that LiFe batteries are safer, but I have never used them. I don't currently have any LiPo's. I gave them away when I took a break from the R/C airplane hobby.
 
If you end up building keep in mined the biggest battery killer in a launch controller is the cable. The controller in the picture I built in 1982 and it still is my go to for most launches. Powered by 6 C batteries I can get at least a couple dozen launches before they start to fade. At 20 feet I use at least a 16 gauge cable. If I am firing multiple motors or going beyond 20 feet I grab my 12 gauge monster cable. With a 12 gauge cable at 50 feet it packs almost the same punch as 20 feet of 16 gauge. I can also patch in a 12 volt 8 amp lawn tractor battery if needed. Continuity is checked by a separate 3 volt circuit. Originally the check light was wheat grain bulb but the led makes it way easier to see.

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