View Full Version : Different LED mod for DX7

04-17-2009, 12:12 PM
I thought I'd revisit this topic since this info is kind of hard to find anywhere...

SB's mod works great, (http://www.helifreak.com/showthread.php?t=49174) I just thought I post how to wire a LED so that they will come on even if using the buddy port when using a sim.

Here's what my DX7 looks like. I chose to place them at the top so the lights were not facing my eyes, and so they could be seen easily from any angle. Plus you can access that area of the radio without having to take anything else apart, or out of the radio. :thumbup:


Blue LED. Rated from 3.8V to 15V
Here's an extremely useful tip. Frost the outside of the led by lightly sanding the whole outside with some very high grit sandpaper (like 1000). This will cause the light to diffuse around the whole LED. If you don't you will not be able to see it nearly as well. Also note the LED's do have a positive and negative lead and cannot be reversed. Make sure to pay attention to what side is what when wiring.

470 Ohm resistor. Use 1 per LED. You can just series them in line on the positive lead side of the LED.

First mark where you want the LED's to go on the case. Drill out the holes with a 3/16" drill bit. Assuming your LED's are the same size as mine (which I think they are basically standard) that size hole will fit them nice and tight. Be carefull when drilling and make sure the drill doesn't get pulled into the radio and start drilling into things in there ;)

Next wire your LED's together in series. Use a small bit of wire and solder the positive lead from one LED to the negative side of the other. Then solder about a foot's length of red wire to the positive side of the two LED's and black wire to the negative side.

Also take this time to solder two resistors together. Just use enough of the leads to get them together.

Push your LED's into the holes from inside making sure that the Positive side lead on on the right and the negative is on the left. Tack them in with some thick CA from the inside. Run the black wire down the left side and solder to the charging plug lead shown below in the picture.

Run the red wire down the right side. Before soldering, inline the resistors and cover with heatshrink. Solder the red wire to the buddy jack lead shown below.

Solder the negative lead to this post on the charging jack

Solder the positive lead to here on the buddy port jack

That's it. Simply put the cover back on and you should be good to go. Wired this way the lights will go on either when you turn on the radio, or if you plug into the buddy port.


04-17-2009, 03:45 PM
Kewl , I put a single LED at the top of my DX7 last weekend . I've never left the Tx on by accident,just thought it needed some type of power on indication other than the LCD screen . I may switch it out for a slightly brighter one in the future. The green one with a built in resistor was just in my tool box :)
Mine comes on with the main switch and the sim port as well, it is about half as bright when running from the sim port though. I soldered my positive lead directly to the 1st leg (Left side) of the regulator .