Batteries

Jul 06, 2005 23 Replies

I have a 7 amp hr 12v gel-cell battery that I use for my 40M QRP CW rig. Much like the kind you'd use for emergency lighting. I was just curious if the same battery could be used for model rocketry.



Clearly a lighted rocker type switch could be used to not complete but 'energize' the circuit and then something as simple as a doorbell for a 'launch' button.



Know what I mean?


Should work fine, as long as you are not firing off clusters. For clusters you should use auto batteries; Ni cads work good too.

What kind of QRP rig do you have. While I don't have my Ham ticket yet, my friend had a Heathkit that he built from a kit. The last time I talked to a Ham he said that most of the rigs on the air now are Yazue's and Kenwoods.

John

For a starter go here:

formatting link
Yaesu, Kenwood and Icom are the 'Big Three' meaning the three most commonly bought radios. Everyone has their own opinion as to which is best. Very similar to: Do you like Estes, Fliskits or homebrew?

I have an Oak Hills Research 100A

formatting link
If you are interested in Ham Radio go here:
formatting link
From there you can find somewhere in your local area to take a test....from this site you can download the 'answers' for the technician test, memorize them and pass the test...it's as simple as that.

OK.....here it its.....

formatting link
If it isn't CW it's just CB.............

You're on the right track. I have used a similar cell to do Estes cluster up to and including 4 engines and it lights Aerotech Copperheads about as well as anything.

Nice....

tnx for the feedback. Nice to see an NRA # too, I'd give ya mine but it's stuck somewhere in my wallet!

:)

The gell cell should be fine.. But... The lighted rocker switch is probably not.. (if this is meant for the safety interlock). The interlock should be removable..So you can take it with you when you're at the pad. Plus, a lighted "arm" switch might not that visible standing in a field under a bright midday sun.

Here's what I did on my controller. (cheap and it works). Install a phono jack on the controller. This is your "switch". Take a phono plug and short the two connectors.

When the plug is in the jack, it's armed. When the plug is in your pocket, it's disarmed.

Roger Roger

You've given me even more ideas....Thanks!

The more I think of it, the more I like it.

That's an EXCELLENT idea.

Thanks Woody!

If you want "armed" feedback, use a pizo buzzer (couple bucks at ratshack), as it won't be washed out in bright sunlight.

*Wonderful* suggestion! Is it an original "Woody", or did you discover this somewhere else?

Not my idea, by any means.. Check out the controller designs on ROL (infocentral). I can't even recall where I saw this first used, but it's cheap, easy, and if you lose the key, another can be made quickly.

Strictly speaking, you should have a removable key interlock somewhere on the power side of the controller. Many people use a shorted phono plug in homebrew controllers. My controller, and the ones we build in class, use a lot of household electrical components; they are cheap and easily handle the current loads of my non-relay controller. The interlock is half of a dual wall socket with a shorted power plug and the launch cable is an extension cord which plugs into the other socket. The female end of the extension cord plugs into a lamp cord tail with clips. A light switch is the main power ON/OFF switch. The most expensive part is a 30A pushbutton fire switch. A current limited LED, piezo buzzer, and small pushbutton all in series make up the continuity circuit (about 12 - 15ma through the igniter with a

13.8V lead acid motorcycle battery during test). We use a power strip at the pad end for drag races.

The controller/battery is very reliable and lights 7 motor BP clusters (Estes igniters) without a problem. It also fires copper bridgewire igniters (James Yawn style) and has even launched a modroc on bare nichrome.

I really like the idea of a 'put in your pocket shorted out phono plug' and the piezo buzzer is also a great idea!

Thanks!

I use three gel cells in parallel actuated through a simple relay. Will cook off anything. Try

formatting link
Got mine for $9.99 each.

Kurt Savegnago

Perfect!

Bob Kaplow NAR # 18L TRA # "Impeach the TRA BoD" >>> To reply, remove the TRABoD!

It'l work fine for clusters, at least with Solar ignitors. Maybe not with a dozen Magnelight ignitors/ :-)

Bob Kaplow NAR # 18L TRA # "Impeach the TRA BoD" >>> To reply, remove the TRABoD!

OK if it's not in the direct firing circuit, as in my relay launcher. Phono plugs just don't handle the high current of a launch system.

Bob Kaplow NAR # 18L TRA # "Impeach the TRA BoD" >>> To reply, remove the TRABoD!

It's old. VERY old. It was around when I was first flying in the mid 60s.

And as I said, it's a BAD choice if it's in the main power loop. I use a mini phono plug as the safety key for my CHAD relay launcher:

formatting link
Bob Kaplow NAR # 18L TRA # "Impeach the TRA BoD" >>> To reply, remove the TRABoD!

A ham license can be quite handy if you have a "difficult" recovery area, or like high-altitude flights. Check out

formatting link
for some inexpensive transmitters that can be used for tracking rockets. The biggest expense is the 70cm handheld receiver; I bought a Yaesu VX-2R, and even with that included, I can have a complete rocket radio tracking setup for less than $250, which is less than what Rocket Hunter and Walston receivers will cost you, alone.

-Kevin

Join the Discussion

Have something to add? Share your thoughts — no account required.

Didn't find your answer?

Ask the community — no account required