Launch Controller LED

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MartyAMC

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I finally finished my home built launch controller using LEDs from Radio Shack. I got the chance to field test it last week and the LEDs were less than sufficient. Although it performed flawlessly it was almost impossible to see the LEDs in the bright sunlight. :(

Does anyone have a manufacturer and part number for red and green 12 volt, T1 3/4, 5mm high intensity LEDs.

Thanks
 
Hi Martyamc,

Here is a thread to ALL Electronics. They have plenty of LEDS to choose from and the price is right.
https://www.allelectronics.com/make-a-store/category/340/LEDs/1.html

You may want to shade or cup your LEDS on your controller. Experimenting with different mounting options may make it easier to see than others.
You may also want to try a blinking LED or tricolor which may be easier to see in
bright day light.

Good Luck
CornyL
 
Use a clear LED that is red (or green) when it's powered. They're a lot easier to see.
 
you might want to visit www.superbrightleds.com

checkout the specs on the various leds before you buy. click on the stock number to see the spec for each LED.

They have many that will fill your need. Service is super and deliveries are USPS fast.
 
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In direct sunlight it will be difficult to ascertain illumination of any but the most extremely bright lamps. The simplest solution would be to make a hood to shield your lamp from direct sunlight or, in addition to a lamp, add a buzzer.
 
In direct sunlight it will be difficult to ascertain illumination of any but the most extremely bright lamps. The simplest solution would be to make a hood to shield your lamp from direct sunlight or, in addition to a lamp, add a buzzer.


Nope. All the superbrights I've seen are VERY easy to see in bright sunlight. They are SUPERbright.

For plain old Estes controller lamp replacement, I've been using these:

Website is down during their move, but save this for later:
https://www.pinballlife.com/
https://www.pinballlife.com/index.php?p=product&id=1174&parent=192

Another source is:
https://www.centsibleamusements.com/pinball-led-44-47.aspx
 
The superbright ones are all 12V, correct?

Unlikely. LEDs are usually rated at a current draw and voltage drop. The general rule of thumb I've always used is 20 milliamps ( 0.020 Amps) and 2.2 Volts. This means that you need 2.2 VDC across the LED so it draws 0.020 amps and obtains it's rated brightness. Different types of LEDs will have different ratings. Some have higher or lower voltage and current ratings.

Yes, you can get LEDs that are designed for specific voltages, 12VDC, 24VDC 115VAC, etc. These all have some sort of circuit or resistor built in to allow the use of a specific voltage. The LED you want may not have a model available that is designed for the voltage you want to use. I that case, you must determine the size of the load resistor you need.

The basic equation is E = I * R (Voltage = Current times Resistance). Since we know the voltage drop and the current required, we change the equation around to find R = E/I. The standard LED would be 2.2VDC and 0.020 Amps of current or R = 2.2/0.020 We want to find what resistor we need to drop the remaining voltage. Since the current stays the same through the whole circuit, the voltage drop will be different. A fully charged car battery is actually 13.8 VDC, so we will use that. 13.8 - 2.2 = 11.6 VDC Using R = E/I or R = 11.6/0.020 = 580 Ohms. This is the size resister you need to put in series with the LED to use it at its maximum brightness in a circuit powered by a car battery.

Since most LEDs will work with voltages and currents outside the nominal range, you can determine the current levels, which affect brightness, by adjusting the resistance you put into series with the LED. If you wanted to limit the current in a continuity check to 10 mA. You could adjust the resistance to control current.
 
what colors you want?
I have a few, Green, blue and Red?
all have extreme brightness, 70Kmcd, don't look to long at them, then just use a 510 to 600 ohm resistor to limit your current
But they are all 10mm versions, not 5mm
 
Use a clear LED that is red (or green) when it's powered. They're a lot easier to see.

Bill is right, I got a blue LED, in a clear "case", at Radio Shack, and it is extremely bright. I retrofitted an Estes Launch Controller, and epoxied the LED into the bulb socket. A current limiting resistor was soldered to the LED, and wires to the brass contacts inside the controller. This particular LED required 3.8 VDC to light, and the desired current was 20 mA. I designed mine for 6V usage, since I wanted a controller to run with the standard, internal AA batteries. To figure out the current limiting resistor, you divide the voltage over the resistor (6-3.8=2.2 V, in my case) by 20mA, and you get 110 ohms. Nearest value is 120 ohms (meaning a little less current), or you could drop to 100 ohms, and go with a little higher current.

A neat little calculator for LED current limiting resistors can be found at https://www.ledcalc.com

A bayonet base LED lamp would be easier to install, but I liked the idea of a blue LED for something different, and I wanted to experiment a little. Also, I wanted to make sure the draw of the lamp was low, in order to be safe for Quest and other low-current igniters. If you buy some of the preassembled LED modules, make sure you know the total current draw. They may be really bright, but also drawing a large enough current that it may cause problems with continuity checks -- setting off your igniters in the process (that is, not any better than the incandescent lamp they replace).

I have not tried any of the bayonet-style LED lamps yet, but maybe someone can post their results -- how much current do they draw? Or are they safe with low-current igniters? I could not seem to find any specs.
 
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Thanks everyone. A great lesson and several potential suppliers.

Marty
 
... and you get 110 ohms. Nearest value is 120 ohms (meaning a little less current), or you could drop to 100 ohms, and go with a little higher current.

Or put a 100 ohm and 10 ohm in series. Of course you have to check the tolerance. You could get a 100 ohm 10% that is at or near 110 ohm.
 
Or put a 100 ohm and 10 ohm in series. Of course you have to check the tolerance. You could get a 100 ohm 10% that is at or near 110 ohm.

True, but if you're retrofitting an Electro Launch, getting one resistor soldered onto the LED, and mounted inside the case, was challenging enough. The manufacturer's recommended current is spec'd or rounded to a nice convenient value. And with tolerances on the resistors, going up or down a resistor size isn't going to make that much difference. It you overdrive it slightly, the LED might burn out in 15 years of use, rather than 50 ...
:)

If I can find it, I'll post the Radio Shack part number. They look pretty nice in the Electro Launch, although they are not a simple drop-in solution. I seem to recall these were available in red, green, and clear, as well as the blue I bought.
 
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I use the SuperbriteLEDs in the custom controllers I build for club use. They are fantastic and are visible in full sunlight. Price is about 50 cents in quantity, but like anything if you buy a small amount the shipping will raise your unit cost a lot.

https://www.superbrightleds.com

I use RL5-G8020 for green and RL5-R8030 for red. These are 8000 mcd I think which isn't the brightest you can get but they are bright enough.

Minimum current with good brightness as judged by eye is 8ma to 12ma. 18ma is very good. And 20ma is optimal. For 12v use you just need to chose the proper resistor for your application. My designs use 18ma current or as close as I can get to that.

I have a ton of these in the parts bin. If you want, PM me your address and I'll mail you a few green ones (or red if you prefer).
 
Thanks for the lead and info David. Following up on Micromeister's lead I've already ordered the exact LEDs you listed.

Thanks everyone.

Marty
 
Very good. I recommend once you have chosen your current limiting resistor, and if you have a multimeter, check the actual LED current in your circuit and the ignitor current under continuity check conditions to make current is what you want. Avoiding disappointments and surprises.
 
Thanks again to everyone for your suggestions and advise. I received the superbright 8020 and 8030s and put them in the launcher. Even driving them thru the 1k resister I already had installed in the launcher they are so bright in the garage it hurt my eyes. Outside in full sun light they're easy to see. :D
 
Just ordered 50 more of the red LEDs to replace the incandescent lamps in Estes controllers for folks who attend our club launches.

https://www.pinballlife.com/index.php?p=product&id=1174&parent=192

Completely Q2G2 safe and you simply rotate and remove the old lamp and insert and rotate the new LED lamp to install. And you can also safely increase the voltage by bypassing the battery compartment and using a different power source.

It is still easier to simply order one of these in the first place:
https://www.estesrockets.com/rocket...tems/002240-pro-series-iitm-launch-controller
 
Excellent source Fred, and really cheap. Do you know what the current draw is? They also make a single led version as well which would be about 20 ma max.

Bob
 
Here is my info that i have saved in a MS Word document since I am asked about this all the time:

Continuity lamp current and firing current tests.

I tested several controllers and lamps/LEDs/power sources. Let’s start with the Estes E controller and a fresh new Electron Beam controller from a new launch set, that way we could see side by side comparison of the effects of the 15 feet of thin launch leads vs. the 30 feet of thick launch leads even when they use the identical power source of 4 AA alkaline batteries.

I started by testing each battery and they produced 1.59 volts individually. I then installed them in the controllers and tested the voltage delivered to the micro clips when you arm and hit the Launch button.

Electron Beam: 5.9 volts
Estes E: 6.3 volts

Interesting – less resistance in the Estes E controller.

Now for the current tests. I connected the micro clips to the ammeter and measured the current when armed (continuity lamp only) and when the Launch button was pressed.

Electron Beam:
Continuity: 190 mA
Launch: 2.75 A

Estes E:
Continuity: 210 mA
Launch: 3.72 A initially, dropped to 3.65 A and then rose to 3.75 A as testing progressed (battery heating effects?)

So, obviously the Estes E controller can deliver more current to the igniter. The thicker wires have much less resistance, so they more than make up for the longer wires.

Next a Quest controller (the beeping electronic type) with the internal 9 volt alkaline battery. Battery tested at 9.2 volts. Voltage at the micro clips was 9.2 volts.
Continuity current: 12.5 mA
Launch current: 3.3 A dropping to 2.9 A after holding the button for 5 seconds. After a rest period it returned to 3.3 A.

Estes Electron Beam controller with LED replacement lamp (pinball machine triple LED in bayonet base rated 6.3VAC) https://www.pinballlife.com/index.php?p=product&id=1174&parent=192
Continuity tests:
4 x AA internal alkaline batteries: 37 mA
Battery compartment bypass to a 9 volt battery pack (6 x C): 75 mA
Battery compartment bypass to a 12 volt lead acid scooter battery: 115 mA

Estes Command Control controller continuity tests:
7.2 volt internal battery pack: 30 mA fluctuating (from electronic circuit/beeping)
2 x 7.2 volt = 14.4 volt internal battery packs: 70 mA fluctuating (from electronic circuit/beeping)

Estes Astron controller with 30 feet of 18 ga launch leads continuity test:
12 volt lead-acid scooter battery: 110 mA

Estes Pro Series II controller with 6 C alkaline batteries:
Safety key only: LED lights up with 7.5 volts at the clips and 29.8 mA
Safety key and arm switch: LED lights and buzzer sounds with 8.45 volts at the clips and 44.5 mA
Safety key and arm switch and launch switch: 9.09 volts at the clips with 3.17 A (with 2 inches of 31 ga nichrome wire I measured 2.35 A and it glowed red hot).



Excellent source Fred, and really cheap. Do you know what the current draw is? They also make a single led version as well which would be about 20 ma max.

Bob
 
My LEDs arrived yesterday (USPS Priority).

I also ordered 100 Mueller BU-34X clips. They are in stock at Mueller but not in stock at the distributor, so we'll see if the lead time is 8 weeks or much less. I ordered more since my last batch of stainless clips from NARTS is almost used up. I also have 9 copper and copper plated steel clips that I will use to fix other controllers that had their original Estes clips corrode away after years (or the internal wire broke inside the insulation just below the clip in the "wrist" area.).
 
From a color perspective IMHO we found the white LEDs work the best. We use Part Number: RL5-W18030 from Superbrightleds.com to indicate which pad relays are energized and they are easily seen at 300 feet.

Steve G
 
Use a clear LED that is red (or green) when it's powered. They're a lot easier to see.
X2

In direct sunlight it will be difficult to ascertain illumination of any but the most extremely bright lamps. The simplest solution would be to make a hood to shield your lamp from direct sunlight or, in addition to a lamp, add a buzzer.
This works too...

From a color perspective IMHO we found the white LEDs work the best. We use Part Number: RL5-W18030 from Superbrightleds.com to indicate which pad relays are energized and they are easily seen at 300 feet.

Steve G
A good example of this is look at an LED flashlight in the sun. Yeay, You can see 'em.
 
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