I replaced all the light bulbs in my old Estes controllers with LED's decades ago. I used resistors salvaged out of old VCR's and stuff, desolder them and then solder them onto one of the legs of the LED. If you want to make it easy on yourself, just get "LED indicators" which are designed to run on 12 volt automotive systems, and have a built-in resistor to protect the diode semiconductor bridge. Or you can calculate the resistance needed by using the old "Ohm's Law" which is V= I/R which is volts= amps/resistance (volts= amps/ohms) and of course using simple algebra to get the different values. Google can get you more explanatory results.

What I did was remove the bulbs, drill the Estes controller for two LED's... one is wired directly across the battery terminals and lights up whenever the battery is connected-- this shows a "good connection" at the battery (I ditched the stupid lousy AA batteries and the old "Polaroid flat battery" in my old "Pola-pulse" battery controller and installed lamp cord with a pair of battery charger clips to connect directly to a car battery or car battery jumper pack for launches-- no more dead/weak stupid AA or high priced impossible to get Polaroid batteries!) so if the charger clips have a good connection to the car battery, the "batt" LED is lit up at all times. Then another LED/resistor is soldered in with wire and connected up between the contacts where the old "continuity" bulb would have been. It only lights up when the key is inserted IF the microclips have good contact with the ignitor and the ignitor has a good circuit (not a broken element/connection).

Here's some pics and wiring diagrams to help you out. It's easy enough to convert regular Estes controllers (or make your own with momentary switches and hand-made contacts, and use a bit of Romex wire for a safety key-- I made my own out of copper house wiring straightened out and then one end bent around in a circle and soldered to itself to make a loop handle for the key, which will replace the old steel Estes keys which can get corroded or make poor contact, with much more conductive and less prone to corroding copper keys that will make better contact and pass more current than a steel key). Just get a few scraps of copper house wiring, remove the conductors from the sheath and strip off the insulator plastic and find the right diameter pieces that will fit in the holes in the Estes controllers, straight them with pliers and bend one end around with pliers into a loop and solder it to itself to close the loop to tie it off to a string or whatever.

It's also easy to convert Estes controllers to send WAY more power to the launch pad, for quicker ignitions and less resistance or failed launches. I remove all the dinky "bell wire" that Estes uses in their controllers with much heavier gauge/current carrying capacity "electric cord" which you can get in bulk or just get cheap twin-lead indoor extension cords and cut them up for cord. Strip the ends and solder or attach to the internal contacts of the Estes controllers where the dinky bell wire is connected up. Tie a knot in the cord for strain relief just inside the controller, and cut or drill a hole in the end of the controller for the leads to come out
and you have a good controller then. One set of leads can go to an external battery, and another set for the launch clips. What I started doing was getting some of those cheap extension cord end repair plugs and installing them on the controllers. With those, it's easy to use REGULAR OUTDOOR EXTENSION CORDS to run the leads anywhere you want-- for instance, you could run numbered extension cords from each pad to the RSO table at the launch, and he would physically plug his end into the main launch battery (car jumper battery pack works EXCELLENT for this) which would enable only one pad at a time-- just plug in the pad about to launch into the extension cord end with a pair of battery charger clamps or cigarette lighter plug (I'd use the battery charger clamps as they can pass more current with less resistance) to plug into the battery or jumper clamps on the pack, to send power to each pad in turn. The Estes controllers (or homemade equivalents) are equipped with external battery cords using a regular lamp cord plug-in (two prong- which can be salvaged off old extension cords, or old broken appliances-- just cut the cord off the old appliance at the appliance for a handy cord!) which will plug into the end of the extension power supply cord coming from the RSO table. The LED indicator will show when the system has power applied to that controller via the "PWR" LED which lights up whenever power is applied to the controller. Another lamp cord lead with a cheap female repair plug (which can be bought very cheap, or salvaged from old extension cords) is wired up inside the controller where the original microclip bell wire leads were attached, with a knot for strain relief inside the case and coming out a hold drilled or melted or carved into the case, can then be used to send the power to the pad and ignitor. With a female repair plug on the lamp cord lead-outs, a regular extension cord of whatever appropriate length can be strung out to the launch pad for that launch cell and used to send power from the controller to the rocket motor ignitors. The extension cord is plugged into the controller female end, and a "clip whip" or short piece of old appliance cord or extension cord with a male end is plugged into it, the wires separated, and a pair of microclips is soldered onto the ends of the stripped wires, which is connected up to the rocket. The key is inserted and the "ARM" (continuity) LED lights up, showing a good connection between the launch controller and the ignitor clips and that the ignitor itself is passing a light current for continuity and ready to launch. Press the button and off she goes. The RSO would then unplug that extension cord from his master battery and plug in the next pad's extension cord, enabling the next cell to launch. Each cord can easily be labeled at each end with tags or even painters tape or write on them with a Sharpie marker.

After the launch, each extension cord is unplugged from the system and rolled up and stored, all the extension cords from the controllers to the pads are rolled up and stored (separately in a box or bag so they don't get mixed up, or just label two for each launch cell and it's all good) and the clip whips are plugged directly into the lead out of each controller so they stay with it in storage. The power supply clip whip (plugged into the car battery jumper pack or connected to a vehicle at the launch) can be plugged into the power supply lead out on one of the controllers so it's handy for the next launch as well, and all the cords and controllers stored in a box for use at the next launch. Car battery jumper packs are also easily charged by plugging them directly into a car cigarette lighter plug in a vehicle so it's charged and handy for the next launch, and does double-duty boosting off cars if someone's dome lights kill their car battery during the launch (which I've done for a guy at a launch before!) or in the owner's vehicle during the winter or whatever when batteries tend to get weak and fail.

Here's some diagrams and pics to help you out. If you need more information, just post here or PM me... OL J R

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