# Telephone Wire?

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##### Well-Known Member
McKaila and I video almost all of our launches. Its alittle hard to track and film the rockets from the end of our 15 foot launch control. (the basic Estes)

Could I use telephone wire for an extension? If its too thin gauge wire, could I 'double' them up; 4 wires, paired to 2?

I thought with a little fabrication to a controller, I could 'plug in' whatever length extension I wanted. 12, 25 or 50 foot...

I searched here and found no such reference.:confused2:

This would be for LPR only, 18mm C's are the largest motors we launch.

Thanks!

#### n5wd

##### Well-Known Member
Could I use telephone wire for an extension? If its too thin gauge wire, could I 'double' them up; 4 wires, paired to 2?
Sure, you can! At some point (probably more length than you're going to want) you'll see that the voltage delivered at the end of the wire will begin to have trouble lighting the igniters after you've used the battery for a while... that will happen quicker with the extension simply because of the added resistance of the wire.

But, for a quick and dirty solution to your problem... give it a try!

#### powderburner

##### Well-Known Member
pros:

-quick
-easy to find wire materials
-cheap
-with a good battery, hey, IT WORKS! (always something to be said for that!)

cons:

-solid conductor is prone to breakage after too much bending/flexure (phone wire is designed to be installed once and left in place)
-small conductor gauge not designed to carry much power efficiently

I might point out that if you are re-working your launch controller, you are already talking about investing some time and effort. You might want to just bite the bullet, invest $20, buy a 50 foot extension cord at the hardware store (or 50 ft of speaker wire, probably in the same price class, thus the recommendation for the extnsn cord with a brightly colored cover), and do it right. You'll be able to safely launch mid-power rockets (35 ft set-back) and use your launch controller all the way up to high-power rockets. #### Handeman ##### Well-Known Member TRF Supporter The other alternative is to use the controller the way it is, and instead of firing the rocket, it fires a 12VDC relay. The relay then passes battery voltage to the pad. In a very basic way, that is the way the HPR launchers work. The battery stays at the pad so it deliveres maximum current without loss from the long wire runs. The launch controller only activates the relays at the pads. #### TheAviator ##### Well-Known Member The other alternative is to use the controller the way it is, and instead of firing the rocket, it fires a 12VDC relay. The relay then passes battery voltage to the pad. In a very basic way, that is the way the HPR launchers work. The battery stays at the pad so it deliveres maximum current without loss from the long wire runs. The launch controller only activates the relays at the pads. The problem is an Estes controller doesn't have the voltage to close the contacts on a car relay. You need at least 9V to do it, and 12V is recommended. #### Handeman ##### Well-Known Member TRF Supporter The problem is an Estes controller doesn't have the voltage to close the contacts on a car relay. You need at least 9V to do it, and 12V is recommended. You could use a solid state relay. They usually work on 3 - 12VDC and they can pass the 12VDC for the car relay, or pass the 12VDC directly to the igniter. It's probably not the best solution, but it would definately work. #### Handeman ##### Well-Known Member TRF Supporter I bought a 50 foot spool of 16AWG lamp cord for mine. #### luke strawwalker ##### Well-Known Member McKaila and I video almost all of our launches. Its alittle hard to track and film the rockets from the end of our 15 foot launch control. (the basic Estes) Could I use telephone wire for an extension? If its too thin gauge wire, could I 'double' them up; 4 wires, paired to 2? I thought with a little fabrication to a controller, I could 'plug in' whatever length extension I wanted. 12, 25 or 50 foot... I searched here and found no such reference.:confused2: This would be for LPR only, 18mm C's are the largest motors we launch. Thanks! Your best bet for lengthening your launch leads is regular old lamp cord. You can often get rolls of the stuff cheap at the dollar store. It's better than bell wire for two reasons: 1) it's bigger, and the bigger the wire, the more current it can carry (lower resistance). This means that you'll get more power to your ignitor, which is a good thing, especially when you consider that the Estes controllers powered by AA batteries are barely up to the job when using the standard wire guage/length that Estes puts on their controllers. 2) it's multistrand. Multistrand wire carries more current than an equivalent size of solid wire. Multistrand is also more flexible and less likely to break, and MUCH easier to roll up and store. Do a search here in the forum using the 'search' button and look for articles on launch controllers. There are several threads that I know of; I've posted to most of them. There are some good tips (and photos) in there of how to mod your Estes controller for more power and longer length wires, if you need them. Remember as well, the longer the wire, the more voltage you really need to push a given amperage of current through it, so don't make the wires TOO long. Of course switching to 12 volt batteries obviates that concern, until your leads get to about 50 feet or so. Later! OL JR #### 1974_Trident ##### Well-Known Member I built my launch controller with 100 feet of 14 AWG wire from Big Orange. It's the wire they sell for wiring 12v garden lights. I paid about$30 for the coil of wire.

Sitting 100 feet back from the launch pad allows a great view of my rockets taking off and is a safe distance for even the mid power loads. The 14 gauge wire passes enough current to fire Copperheads.

#### RoyAtl

##### Well-Known Member
The problem is an Estes controller doesn't have the voltage to close the contacts on a car relay. You need at least 9V to do it, and 12V is recommended.
30 years ago I built a launcher using an Estes BigFoot ( sort of an updated ElectroLaunch where the D-cell batteries were in the base) and a power transistor as a solid state relay, using instructions in an article of the Model Rocketeer (predecessor of Sport Rocketry). I used 100ft of speaker wire.