View Full Version : Light for DX7
slider46
10-21-2007, 08:30 PM
I have been thinking about adding an LED light to the DX7 radio so I will be able to see the TX is on at a glance like all of the other radios I have ever owned.... Has anyone done this or know how to do it???
i also need a bright *** LED for mine today is the third time i have got in my truck only to hear the faint beep of a dead DX7 :arggg:
PTFlyer
10-21-2007, 09:32 PM
I could use one myself........someone on here must know how to do this and is willing to explain to the rest of us...perferably with pictures...
i can do it. i will break out my digital camera and show everyone how?
Where do YOU want the LED at?
PM me, or post here. let me know.
Rodney
10-22-2007, 02:57 PM
Just use a Infina-Ion battery and you can leave it on even longer, 15 to 16 or more hours. LOL
PTFlyer
10-22-2007, 05:08 PM
i can do it. i will break out my digital camera and show everyone how?
Where do YOU want the LED at?
PM me, or post here. let me know.
I figure up top by the flight mode switch or on top in front of the antenna would be the easiest place to put one?
I figure up top by the flight mode switch or on top in front of the antenna would be the easiest place to put one?
I was thinking of that or modifying the whole radio and moving the neck strap point below the switch and put the led where it used to be.
just a thought. i'll start on it later tonight to find a good point to solder in to.
ChasHeliCop
10-22-2007, 08:10 PM
I was thinking of that or modifying the whole radio and moving the neck strap point below the switch and put the led where it used to be.
just a thought. i'll start on it later tonight to find a good point to solder in to.
Ticidytoc already did that mod......
See "Finless" post on this forum
http://www.helifreak.com/showthread.php?t=33828&page=2
http://www.helifreak.com/attachment.php?attachmentid=19052&d=1177449238
Tickitytoc already did that mod......
See "Finless" post on this forum
http://www.helifreak.com/showthread.php?t=33828&page=2
Perfect. thats the first part.
ChasHeliCop
10-22-2007, 08:42 PM
The LED is where the old strap ring used to be.
oh there is an led there. lol (i feel dumb)
i looked over the post. i don't see any of the wireing on there
ChasHeliCop
10-22-2007, 09:32 PM
I don't think he did a picture build.... or at least I haven't found it.
ok. i'll work on that then.
and it dosen't mater where everyone wants the led. you can put it anywhere your heart desires. i just want mine there.
but i'll show everyone where to hook to ;)
PTFlyer
10-22-2007, 09:54 PM
ok. i'll work on that then.
and it dosen't mater where everyone wants the led. you can put it anywhere your heart desires. i just want mine there.
but i'll show everyone where to hook to ;)
Yes..please do....some of us don't know where or how to go about hooking up the LED without burning it out, or which led ...
I looked at the Ratshack led's
I was thinking of using one of these because it's easy tro get:
http://www.radioshack.com/product/index.jsp?productId=2062556&cp=2032058&categoryId=2032058&kwCatId=2032058&parentPage=search
but it says:
Typical Voltage is 2.1, with a maximum voltage of 2.8V
so I have no clue how to go about hooking it up/ or even where to hook it up...or even if I can even use that one or if there is some other led I should be using for this....
So please post what you come up with.....thanks..
spork
10-22-2007, 10:25 PM
Typical Voltage is 2.1, with a maximum voltage of 2.8V
For an LED the voltage is sort of a non-issue. The ticket is to control the current. Typically you'll find LED's that run anywhere from 10 to 100 mA. Based on this you can just run the LED in series with a resistor and through the on-off switch. Use this equation to figure out which resistor:
V = I x R
Where:
V is the voltage. In this case you'll be plenty close if you use your battery voltage - 2.0 for the drop in the LED (or probably fine even if you just take the battery voltage)
I is the current. 100 mA would be 0.1 (always compute it in amps)
R is the value of the resistor in ohms
Generally speaking LED's accept a wider range of current than the spec lists. If you over-drive them it will shorten their life, but if it's within any sort of reason they'll still outlast your radio.
Also, you can take a file and remove the dome on the end of the LED. This will make the light pattern far less directional. So you can see it from almost any angle without being blinded by it when looking straight on. If it's too bright, just use a resistor with a higher ohm rating. You can't overdo it with too much resistance - only too little.
But I'm rambling. SB will probably post the exact LED and resistor values that are easy to find and are suitable.
Incidentally the LED you linked to would work fine. Just use it with a resistor anywhere in the 500 ohm range. If it's not bright enough for you, you'll want to pick an LED that accepts a higher current (and use a lower value resistor). For that LED:
http://www.radioshack.com/product/index.jsp?productId=2062342&cp=&searchSort=TRUE&retainProdsInSession=1&y=8&x=9&parentPage=search
5 for .99
PTFlyer
10-22-2007, 11:20 PM
thanks spork.......that's the info I need although I'm electroniclly challanged and would still be guessing if I worked out the math correctly even with the formula........
but let me get this part straight at least....
if I go with the led I linked and use one of those resistors, that you linked ,in line (On the + side of the LED I guess? or would it bridge the +/- leads?) and wire it to the switch I should be all set to go?...given the power at the switch is +/-11.~V
spork
10-22-2007, 11:33 PM
if I go with the led I linked and use one of those resistors, that you linked ,in line (On the + side of the LED I guess? or would it bridge the +/- leads?) and wire it to the switch I should be all set to go?...given the power at the switch is +/-11.~V
Yup. You just put the LED in line with the resistor.
(+11V)--------(resistor)-------(LED)----------(-)
If you can forgive my awful ASCII graphics. If you hook the LED up one way it will light. The other way it will do nothing (but it won't hurt anything).
I assume the on-off switch will give you battery voltage, but I haven't ever been inside a DX7.
P.S. Just to avoid confusion, this doesn't go across the on-off switch. one end goes to the on-off switch and the other end goes to the (-) side of the battery.
PTFlyer
10-23-2007, 01:22 AM
graphics I get!.......
I understand that the + goes to the "on" side of the switch and the - goes to the - side of battery...
I'll check the Voltage at the switch before I wire anything up just to be sure it's got battery voltage....
thanks again.....I'll give it a try tomorrow if I can find the time to get to RS for the parts.....
one more question.can the resistor be wrapped it shrink wrap or does it get hot and need to "vent"..and just shrink the leads to aviod a short?
thanks again for your help...
bullaculla
10-23-2007, 01:50 AM
Let me know when you guys decide to do a backlit LCD screen :D
Night flying is tough with the DX7 :P
spork
10-23-2007, 02:04 AM
one more question.can the resistor be wrapped it shrink wrap or does it get hot and need to "vent"..and just shrink the leads to aviod a short?
Heat shrink probably wouldn't do any harm, but I personally wouldn't cover the resistor. The part I mentioned is a 1/4 watt resistor, and you'll be running in the 1/4 watt range, so I'd let it keep cool personally.
PTFlyer
10-23-2007, 09:58 PM
well........got the LED wired up with the in line resistor....after opening up the radio I see there really isn't really alot of choices where to mount it....I think I've decided to mount it under the speaker opening...
so all that's left is to cut the hole and mount it.....and hook up the wires,......
Now all that's needed is where to hook up the + wire to a switched circut...
I've fished around alittle inside the radio but don't know enough about PCB's to locate the switched side of the on/off switch on the board to piggy back....didn't wnat to fry my board by probing too much.....figure maybe someone on here who is smarter than me will donate the info
spork
10-23-2007, 10:26 PM
It looks like you may have jumped the gun on wiring and heat-shrinking. From the looks of it that LED enclosure mounts from the front side. You may have to unsolder it to mount it and then redo it.
Have you hooked it up to see if it works and is bright enough?
I would think you could simply solder to the "normally open" side of the switch directly, and pick up the ground at the battery or nearly anywhere on the circuit board. Is the switch easy to get at? Can you post a pic of the inside of your radio?
PTFlyer
10-23-2007, 11:31 PM
The LED is "plugged in" to a mini jack so I can un-hook it and change it out if I need to.......also, as you said, the led is front mounted. So I can mount it and than just plug it into the jack.....
as far as the LED.......I used one resistor and it looks to be bright enough to see in bright sunlight but not so bright as to distract you.....I tried two resistors in line and I don't think it would be bright enough to see on a sunny day........(I went with the red LED instead of the green one, as the green one seemed to distracting....
About the switch......well.....the pictures should tell the story..I'll break open the radio and post a couple of pics in a little while.....
it's not that obvious where to make + connection........I did "test" a few soldered posts but no light........then I got nervous and figured I better close it up before I'm shopping for a new radio.....
maybe the pics will give a clue.......
K i did my part a whole how to guide from start to finish even with a coffee break in it
http://helifreak.com/showthread.php?t=49174
PTFlyer
10-23-2007, 11:47 PM
here's some picutres......