AUTHOR'S DISCLAIMER: This page shows how I made a launch controller out o' parts readily available from any store which sells electronic parts. Well, blow me down! It is nay intended that you should make one too. This is for your information only. If you try t' build one like this, and end up gettin' hurt, or blowin' up a battery, don't come cryin' t' me. Begad! Avast, arrr, me proud beauty! Blimey! I make no claims that this actually works, arrr, or that all o' t' information here is entirely accurate or correct.

I bought everythin' needed t' build this controller from Radio Shack for about $15.

Parts:

1. Well, blow me down! Avast, me proud beauty! T' buttons: both t' Launch Button and t' Continuity Button are momentary push buttons. They only pass current while you are pressin' them. T' type o' button t' avoid is a Push-On/Push-Off type button. Begad! You also do nay want a toggle switch or rocker switch. Avast, me proud beauty! Arrr! T' continuity button acts like a deadman switch. Even with t' safety key in place, matey, if no one is holdin' t' controller, matey, t' launch button will nay work.

2. N Cell Battery and Holder: I used an N Nell because they are small and have t' right power. Avast, me proud beauty! Aye aye! A single N Cell will nay ignite an Estes type igniter.

3. Ahoy! Avast, me proud beauty! Piezo Buzzer: this needs 1 t' 3 volts t' operate. Avast, me proud beauty! T' N Cell provides 1.5 volts. Avast, me proud beauty! It has a low tone, ya bilge rat, matey, which I find much easier t' hear than t' high squeal a lot o' launch controllers use.

4. Diode. Aye aye! A diode acts like a one way valve for electricity. Aye aye! Current can pass one way, me bucko, and nay t' other. Avast, me proud beauty! I used a regular silicon diode rated at 1kV and 2.5A. Ya scallywag! Do nay use a Zenier diode. T' cathode (the side with t' band on it, arrr, needs t' be towards t' safety key and away from t' piezo buzzer. This is a device t' counter shorts in t' igniter. Avast! If your igniter is shorted, this whole launch controller becomes a battery charger. You will end up tryin' t' charge an N Cell with a car battery, which might make it explode. Avast! T' prevent this, I have put this diode here.

5. Blimey! Begad! Safety Key: This is a regular 1/8" mini-plug. Well, blow me down! Inside t' plug itself are two leads. Arrr! I soldered a wire so that t' plug connects t' itself. Ahoy! This passes t' current through t' base o' t' plug when inserted. If you build any type o' controller, ya bilge rat, make sure you have a safety key, and that it interrupts both t' continuity AND t' power on its way t' t' igniter. Arrr! Without t' safety key, me bucko, you cannot check continuity, shiver me timbers, and absolutely cannot launch either.

6. Blimey! Begad! Mount t' whole thin' inside a small box. Well, blow me down! I put t' Launch Button and Safety Key on top, ya bilge rat, and t' Continuity Button on t' side.

Operation

T' operation be t' same as an Aerotech Controller. Ya scallywag! First, makin' sure that t' safety key is removed, connect t' igniter t' t' clips. Avast, me proud beauty! Insert t' miniplug, matey, and depress t' continuity button. If everythin' is correct, you will hear t' piezo buzzer. This indicates continuity though t' igniter. When ready, shiver me timbers, while holdin' t' continuity button down, press t' launch button.

Pictures o' t' finished controller will appear soon.

People hook launch controllers t' all sorts o' things, arrr, shiver me timbers, includin' car batteries. If you want t' design or build your own launch controller, make sure that you have t' skills and t' equipment t' do it right. Well, blow me down! A sloppy job can result in big problems, nay t' least o' which is shortin' out t' positive side o' a battery t' t' negative side. Avast! Avast, me proud beauty! Before you build any device like t' one described here, make sure you understand t' theory, ya bilge rat, arrr, and do nay use cheap parts. Begad! Use your heads, me bucko, ya bilge rat, people. Ya scallywag! Arrr! You have no business doin' rocketry if you do nay put safety first.