I don’t know if this is the right place to put this. I’m just getting back into this after launching my last rocket over 20 years ago. Thought I would use these as something to get my 6 year old interested in science etc. I decided to build my own controller as I remember the old Estes one was a bit naff. I call it the Mk 1. I’m sure there are lots I can do to make it more suitable but I’m happy so far.
My new launch controller
- Thread starter Gareth
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Looks nice, gotta love that big mashable button.
Only one thing... are my eyes deceiving or does it run off a single 9V battery?
Only one thing... are my eyes deceiving or does it run off a single 9V battery?
Yes just one. I’ve done some reading using a multimeter and it gives me enough to light those single stage Estes motors. At least that’s what the literature says. As I haven’t used it yet I’m still to see. Fingers crossed. I bought two of those battery enclosures so if it’s not enough, then I’ll connect another one in parallel and hope that gives enough
It only shows that the firing circuit is armed. I haven’t got a continuity circuit yet. I’d like to add a buzzer and light but I need to do a bit more reading on the size of resistor I will need to prevent the igniter from going off!!
In general, 9V batteries are not good for starting the Estes Solar Starters (unsure about the newer "energetic" starters). You need a good-brand, very fresh battery, and even still it often may take several seconds to ignite. It would seem you should have room in that box for a better battery situation. Running two 9V batteries in parallel doesn't sound like a good idea to me.
Some folks in the past talked about using rechargeable Lithium 9V batteries in their 9V controllers... those should have a lot more juice, but you will need to have a compatible charger for it. Some of them come packaged with charger, e.g.: AmazonSmile: EBL 4-Pack 9V Batteries Li-ion 9 Volt Rechargeable Batteries with 840 9V Battery Charger. 600 mAh is not a lot, though, you'll want to recharge before each launch and always have spares.
Some folks in the past talked about using rechargeable Lithium 9V batteries in their 9V controllers... those should have a lot more juice, but you will need to have a compatible charger for it. Some of them come packaged with charger, e.g.: AmazonSmile: EBL 4-Pack 9V Batteries Li-ion 9 Volt Rechargeable Batteries with 840 9V Battery Charger. 600 mAh is not a lot, though, you'll want to recharge before each launch and always have spares.
Any modest LED running off <50 mA will be safe.
Cheers for the feedback. That’s why I’m here
Definitely do some more research before committing to a new battery setup. There are many good options.
I’ll have a look at the lithium 9v batteries. Are there any that are preferred? (I’m still new to this!! As can be seen by the name of the controller, I think there may be others after this with different power sources
I don't know if there are any that are preferred. In general, those aren't a common choice for launch controllers; folks were mainly considering them for existing Estes 9V controllers after having many unsuccessful launches. I *think* all the new Estes controllers are 6V (4xAA), which work better. The Estes Pro Series Controller is 9V (6xC) which is much more powerful than a 9V battery. It also can be connected to LiPo packs for even better performance.
But, if your controller is already set up for 9V batteries, could be worth a shot to try some of the Lithium rechargeables. Not too big an investment.
But, if your controller is already set up for 9V batteries, could be worth a shot to try some of the Lithium rechargeables. Not too big an investment.
I’ll give it a go with both types of 9v battery and see how I get on. The controller is set up for 9v batteries so I would have to pull it apart leaving holes that I don’t want ! Lol. Definitely something to consider for the Mk 2 though and many thanks for your input. It might look the part but I want it to be technically sound too!!
Let us know how it goes. I've seen few if any actual reports of using the rechargeables in a launch controller.
No problems
. Will do First launch in a few weeks and igniters coming next week to do some test lighting.
Gramparocket
Well-Known Member
A 3s lipo works good at 11.7v. fully charged usually runs 12.4v
Cheers for the advice
I’ve got one of these I was thinking of using. I wanted to try the 9v batteries mainly for ease of use and changing. I’ll probably change to a different power source for the Mk2
Gramparocket
Well-Known Member
I would think that would work ok for anything 18to24mm or maybe anything you can light with an e-match
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Beautiful design for a launch controller! Maybe a more professional electrician can verify this idea but if this circuit is already setup for 9v could you use 6x AA's in series? That should give you the same voltage but better mah I would think.
A standard 9V battery is generally made from 6 little 1.5V batteries in series. Check out https://en.wikipedia.org/wiki/Nine-volt_battery for some pictures of the guts disassembled.
So 6 AAs in series is very much like a bigger, beefier 9v battery. Also, putting a few 9V in parallel to get better max current should be a perfectly fine thing to do. If you use rechargables in parallel, charge them all instead of mixing and matching so they don't get too unbalanced.
I personally have been using a 6V lantern battery for power, they work great and I enjoy the brick-like heft.
I actually built a little frame for my PSII controller to hold AA batteries instead of alkalines, so I could try using NiMH AA batteries instead. I never got around to trying it out though.
Given that the 4xAA controller from Estes already work somewhat better than the 9V controllers, 6xAA should be better still.
If you do this, use brand new batteries of the same brand (from same package). Frankly, putting alkaline batteries in parallel makes me nervous. I would certainly not design a controller to operate this way if I had a choice, there are too many superior alternatives.
By all accounts the lithium 9V rechargeables can produce plenty of current, shouldn't need multiple in parallel. I look forward to hearing @Gareth 's report.
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