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SX-424 re-bulb with an LED twist! (Plenty of pictures)

Freezer7Pro

Luxman!
A while ago, I received a shipment of cheap 5mm LEDs for another project. Upon finishing it, I had about twenty left, which reminded me of my rather sad-looking baby Pioneer:



You can literally see the frown on its face, can't you?

While the cheap LEDs are a bit too blue in colour for most other lighting projects I've got going, I figured that they'd fare quite well in the already blue-filtered face of the 424, and thus, the work commenced!

I started by making a little 5-led row, which I placed in the bulb compartment, aimed away from the front as a preliminary test. I was pleasantly surprised when it seemed to work great without me having to make a new light spreader.



The temperature of the LED light is not by any means the same as that of the original light bulbs, as demonstrated by the below picture. However, I wouldn't at all be surprised if the LED light is closer to what the original designer had in mind. After all, it is a lot less green, and more purely blue.

anim.gif


After that successful proof of concept, I proceeded to make a 9-piece LED string:



...which even worked! You can see some of the LEDs I had to discard due to them being DOA, lying to the left of the string.



After successful testing, I mounted them inside the bulb compartment using hot glue. (We Finnish love hot glue, for some reason :yes: )



Let there be light!



It looks like there's some kind of reactor in there. Those cooling vents aren't going to do much good anymore. :D



Putting the face back, it is clear that the project has been a success:



...and the frown got wiped away!



I can finally put this guy in use somewhere without that dark faceplate annoying me.

And if you're wondering, the changes are of course 100% reversible. It's just to put the bulbs back in and remove the wiring for the LEDs if one wants to go all original in the future, for some reason.

EDIT: Made clickable thumbnails rather than humongous beasts of pictures right in the forum. So, go ahead and click the pictures for... Much larger versions.
 
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I have a 424 and 2 434's. Can you draw up a diagram of the hookup's. The whole LED thing has me confused(brain locked in pre-caveman mode) Did you have to use a diode, and or a resistor in the circuit? Were the LED Strung in Parallel or Series? what voltage on the LED's. Amperage for the LED's?

Thanks

Larry
 
:thmbsp:
Lookin Good. My lamps still kickin on my 424, so if it aint broke I don't fix it.
I will keep this in mind for future reference though.
 
I have a 424 and 2 434's. Can you draw up a diagram of the hookup's. The whole LED thing has me confused(brain locked in pre-caveman mode) Did you have to use a diode, and or a resistor in the circuit? Were the LED Strung in Parallel or Series? what voltage on the LED's. Amperage for the LED's?

Thanks

Larry

+43V---680R--->|-->|-->|-->|-->|-->|-->|-->|-->|---GND

The LEDs I used have about 3.4V of voltage drop each, so in total, the LED chain has a voltage drop of about 31V across it. Since I have a 680Ohm resistor in series with them, the current passed through the chain is about 18mA.
 
You did an excellent job with your 424. It looks as good as new!

I did a similar project several years ago with a SX-626. If the bulbs ever go in my current SX-650 I suppose I'll replace them with LEDs, also.
 
+43V---680R--->|-->|-->|-->|-->|-->|-->|-->|-->|---GND

The LEDs I used have about 3.4V of voltage drop each, so in total, the LED chain has a voltage drop of about 31V across it. Since I have a 680Ohm resistor in series with them, the current passed through the chain is about 18mA.


Thanks Freezer, please tell me where you soldered 1. the 680R and 2. the tail end of the string of LEDs?
Very nice work.
 
Thanks Freezer, please tell me where you soldered 1. the 680R and 2. the tail end of the string of LEDs?
Very nice work.

The resistor is soldered straight onto the positive terminal of the main filter cap, and the cathode end of the LED string is soldered right onto the negative one. Aside from some wiring, there's nothing in between. No voodoo in this one. :yes:
 
I know this is an old thread, but I just wanted to say nice work, that's a beautiful blue your tuner has now. Have you replaced the bulbs on the tuner needle and signal meter since then?
 
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